chore: vendor

vendor/github.com/go-git/gcfg/.gitignore

@@ -0,0 +1 @@
+coverage.out

vendor/github.com/go-git/gcfg/LICENSE

@@ -0,0 +1,28 @@
+Copyright (c) 2012 Péter Surányi. Portions Copyright (c) 2009 The Go
+Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/go-git/gcfg/Makefile

@@ -0,0 +1,17 @@
+# General
+WORKDIR = $(PWD)
+
+# Go parameters
+GOCMD = go
+GOTEST = $(GOCMD) test
+
+# Coverage
+COVERAGE_REPORT = coverage.out
+COVERAGE_MODE = count
+
+test:
+	$(GOTEST) ./...
+
+test-coverage:
+	echo "" > $(COVERAGE_REPORT); \
+	$(GOTEST) -coverprofile=$(COVERAGE_REPORT) -coverpkg=./... -covermode=$(COVERAGE_MODE) ./...

vendor/github.com/go-git/gcfg/README

@@ -0,0 +1,4 @@
+Gcfg reads INI-style configuration files into Go structs;
+supports user-defined types and subsections.
+
+Package docs: https://godoc.org/gopkg.in/gcfg.v1

vendor/github.com/go-git/gcfg/doc.go

@@ -0,0 +1,144 @@
+// Package gcfg reads "INI-style" text-based configuration files with
+// "name=value" pairs grouped into sections (gcfg files).
+//
+// This package is still a work in progress; see the sections below for planned
+// changes.
+//
+// # Syntax
+//
+// The syntax is based on that used by git config:
+// http://git-scm.com/docs/git-config#_syntax .
+// There are some (planned) differences compared to the git config format:
+//   - improve data portability:
+//   - must be encoded in UTF-8 (for now) and must not contain the 0 byte
+//   - include and "path" type is not supported
+//     (path type may be implementable as a user-defined type)
+//   - internationalization
+//   - section and variable names can contain unicode letters, unicode digits
+//     (as defined in http://golang.org/ref/spec#Characters ) and hyphens
+//     (U+002D), starting with a unicode letter
+//   - disallow potentially ambiguous or misleading definitions:
+//   - `[sec.sub]` format is not allowed (deprecated in gitconfig)
+//   - `[sec ""]` is not allowed
+//   - use `[sec]` for section name "sec" and empty subsection name
+//   - (planned) within a single file, definitions must be contiguous for each:
+//   - section: '[secA]' -> '[secB]' -> '[secA]' is an error
+//   - subsection: '[sec "A"]' -> '[sec "B"]' -> '[sec "A"]' is an error
+//   - multivalued variable: 'multi=a' -> 'other=x' -> 'multi=b' is an error
+//
+// # Data structure
+//
+// The functions in this package read values into a user-defined struct.
+// Each section corresponds to a struct field in the config struct, and each
+// variable in a section corresponds to a data field in the section struct.
+// The mapping of each section or variable name to fields is done either based
+// on the "gcfg" struct tag or by matching the name of the section or variable,
+// ignoring case. In the latter case, hyphens '-' in section and variable names
+// correspond to underscores '_' in field names.
+// Fields must be exported; to use a section or variable name starting with a
+// letter that is neither upper- or lower-case, prefix the field name with 'X'.
+// (See https://code.google.com/p/go/issues/detail?id=5763#c4 .)
+//
+// For sections with subsections, the corresponding field in config must be a
+// map, rather than a struct, with string keys and pointer-to-struct values.
+// Values for subsection variables are stored in the map with the subsection
+// name used as the map key.
+// (Note that unlike section and variable names, subsection names are case
+// sensitive.)
+// When using a map, and there is a section with the same section name but
+// without a subsection name, its values are stored with the empty string used
+// as the key.
+// It is possible to provide default values for subsections in the section
+// "default-<sectionname>" (or by setting values in the corresponding struct
+// field "Default_<sectionname>").
+//
+// The functions in this package panic if config is not a pointer to a struct,
+// or when a field is not of a suitable type (either a struct or a map with
+// string keys and pointer-to-struct values).
+//
+// # Parsing of values
+//
+// The section structs in the config struct may contain single-valued or
+// multi-valued variables. Variables of unnamed slice type (that is, a type
+// starting with `[]`) are treated as multi-value; all others (including named
+// slice types) are treated as single-valued variables.
+//
+// Single-valued variables are handled based on the type as follows.
+// Unnamed pointer types (that is, types starting with `*`) are dereferenced,
+// and if necessary, a new instance is allocated.
+//
+// For types implementing the encoding.TextUnmarshaler interface, the
+// UnmarshalText method is used to set the value. Implementing this method is
+// the recommended way for parsing user-defined types.
+//
+// For fields of string kind, the value string is assigned to the field, after
+// unquoting and unescaping as needed.
+// For fields of bool kind, the field is set to true if the value is "true",
+// "yes", "on" or "1", and set to false if the value is "false", "no", "off" or
+// "0", ignoring case. In addition, single-valued bool fields can be specified
+// with a "blank" value (variable name without equals sign and value); in such
+// case the value is set to true.
+//
+// Predefined integer types [u]int(|8|16|32|64) and big.Int are parsed as
+// decimal or hexadecimal (if having '0x' prefix). (This is to prevent
+// unintuitively handling zero-padded numbers as octal.) Other types having
+// [u]int* as the underlying type, such as os.FileMode and uintptr allow
+// decimal, hexadecimal, or octal values.
+// Parsing mode for integer types can be overridden using the struct tag option
+// ",int=mode" where mode is a combination of the 'd', 'h', and 'o' characters
+// (each standing for decimal, hexadecimal, and octal, respectively.)
+//
+// All other types are parsed using fmt.Sscanf with the "%v" verb.
+//
+// For multi-valued variables, each individual value is parsed as above and
+// appended to the slice. If the first value is specified as a "blank" value
+// (variable name without equals sign and value), a new slice is allocated;
+// that is any values previously set in the slice will be ignored.
+//
+// The types subpackage for provides helpers for parsing "enum-like" and integer
+// types.
+//
+// # Error handling
+//
+// There are 3 types of errors:
+//
+//   - programmer errors / panics:
+//   - invalid configuration structure
+//   - data errors:
+//   - fatal errors:
+//   - invalid configuration syntax
+//   - warnings:
+//   - data that doesn't belong to any part of the config structure
+//
+// Programmer errors trigger panics. These are should be fixed by the programmer
+// before releasing code that uses gcfg.
+//
+// Data errors cause gcfg to return a non-nil error value. This includes the
+// case when there are extra unknown key-value definitions in the configuration
+// data (extra data).
+// However, in some occasions it is desirable to be able to proceed in
+// situations when the only data error is that of extra data.
+// These errors are handled at a different (warning) priority and can be
+// filtered out programmatically. To ignore extra data warnings, wrap the
+// gcfg.Read*Into invocation into a call to gcfg.FatalOnly.
+//
+// # TODO
+//
+// The following is a list of changes under consideration:
+//   - documentation
+//   - self-contained syntax documentation
+//   - more practical examples
+//   - move TODOs to issue tracker (eventually)
+//   - syntax
+//   - reconsider valid escape sequences
+//     (gitconfig doesn't support \r in value, \t in subsection name, etc.)
+//   - reading / parsing gcfg files
+//   - define internal representation structure
+//   - support multiple inputs (readers, strings, files)
+//   - support declaring encoding (?)
+//   - support varying fields sets for subsections (?)
+//   - writing gcfg files
+//   - error handling
+//   - make error context accessible programmatically?
+//   - limit input size?
+package gcfg // import "github.com/go-git/gcfg"

vendor/github.com/go-git/gcfg/errors.go

@@ -0,0 +1,40 @@
+package gcfg
+
+import (
+	"gopkg.in/warnings.v0"
+)
+
+// FatalOnly filters the results of a Read*Into invocation and returns only
+// fatal errors. That is, errors (warnings) indicating data for unknown
+// sections / variables is ignored. Example invocation:
+//
+//	err := gcfg.FatalOnly(gcfg.ReadFileInto(&cfg, configFile))
+//	if err != nil {
+//	    ...
+func FatalOnly(err error) error {
+	return warnings.FatalOnly(err)
+}
+
+func isFatal(err error) bool {
+	_, ok := err.(extraData)
+	return !ok
+}
+
+type extraData struct {
+	section    string
+	subsection *string
+	variable   *string
+}
+
+func (e extraData) Error() string {
+	s := "can't store data at section \"" + e.section + "\""
+	if e.subsection != nil {
+		s += ", subsection \"" + *e.subsection + "\""
+	}
+	if e.variable != nil {
+		s += ", variable \"" + *e.variable + "\""
+	}
+	return s
+}
+
+var _ error = extraData{}

vendor/github.com/go-git/gcfg/read.go

@@ -0,0 +1,273 @@
+package gcfg
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"gopkg.in/warnings.v0"
+
+	"github.com/go-git/gcfg/scanner"
+	"github.com/go-git/gcfg/token"
+)
+
+var unescape = map[rune]rune{'\\': '\\', '"': '"', 'n': '\n', 't': '\t', 'b': '\b', '\n': '\n'}
+
+// no error: invalid literals should be caught by scanner
+func unquote(s string) string {
+	u, q, esc := make([]rune, 0, len(s)), false, false
+	for _, c := range s {
+		if esc {
+			uc, ok := unescape[c]
+			switch {
+			case ok:
+				u = append(u, uc)
+				fallthrough
+			case !q && c == '\n':
+				esc = false
+				continue
+			}
+			panic("invalid escape sequence")
+		}
+		switch c {
+		case '"':
+			q = !q
+		case '\\':
+			esc = true
+		default:
+			u = append(u, c)
+		}
+	}
+	if q {
+		panic("missing end quote")
+	}
+	if esc {
+		panic("invalid escape sequence")
+	}
+	return string(u)
+}
+
+func read(c *warnings.Collector, callback func(string, string, string, string, bool) error,
+	fset *token.FileSet, file *token.File, src []byte) error {
+	//
+	var s scanner.Scanner
+	var errs scanner.ErrorList
+	s.Init(file, src, func(p token.Position, m string) { errs.Add(p, m) }, 0)
+	sect, sectsub := "", ""
+	pos, tok, lit := s.Scan()
+	errfn := func(msg string) error {
+		return fmt.Errorf("%s: %s", fset.Position(pos), msg)
+	}
+	for {
+		if errs.Len() > 0 {
+			if err := c.Collect(errs.Err()); err != nil {
+				return err
+			}
+		}
+		switch tok {
+		case token.EOF:
+			return nil
+		case token.EOL, token.COMMENT:
+			pos, tok, lit = s.Scan()
+		case token.LBRACK:
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				if err := c.Collect(errs.Err()); err != nil {
+					return err
+				}
+			}
+			if tok != token.IDENT {
+				if err := c.Collect(errfn("expected section name")); err != nil {
+					return err
+				}
+			}
+			sect, sectsub = lit, ""
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				if err := c.Collect(errs.Err()); err != nil {
+					return err
+				}
+			}
+			if tok == token.STRING {
+				sectsub = unquote(lit)
+				if sectsub == "" {
+					if err := c.Collect(errfn("empty subsection name")); err != nil {
+						return err
+					}
+				}
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					if err := c.Collect(errs.Err()); err != nil {
+						return err
+					}
+				}
+			}
+			if tok != token.RBRACK {
+				if sectsub == "" {
+					if err := c.Collect(errfn("expected subsection name or right bracket")); err != nil {
+						return err
+					}
+				}
+				if err := c.Collect(errfn("expected right bracket")); err != nil {
+					return err
+				}
+			}
+			pos, tok, lit = s.Scan()
+			if tok != token.EOL && tok != token.EOF && tok != token.COMMENT {
+				if err := c.Collect(errfn("expected EOL, EOF, or comment")); err != nil {
+					return err
+				}
+			}
+			// If a section/subsection header was found, ensure a
+			// container object is created, even if there are no
+			// variables further down.
+			err := c.Collect(callback(sect, sectsub, "", "", true))
+			if err != nil {
+				return err
+			}
+		case token.IDENT:
+			if sect == "" {
+				if err := c.Collect(errfn("expected section header")); err != nil {
+					return err
+				}
+			}
+			n := lit
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				return errs.Err()
+			}
+			blank, v := tok == token.EOF || tok == token.EOL || tok == token.COMMENT, ""
+			if !blank {
+				if tok != token.ASSIGN {
+					if err := c.Collect(errfn("expected '='")); err != nil {
+						return err
+					}
+				}
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					if err := c.Collect(errs.Err()); err != nil {
+						return err
+					}
+				}
+				if tok != token.STRING {
+					if err := c.Collect(errfn("expected value")); err != nil {
+						return err
+					}
+				}
+				v = unquote(lit)
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					if err := c.Collect(errs.Err()); err != nil {
+						return err
+					}
+				}
+				if tok != token.EOL && tok != token.EOF && tok != token.COMMENT {
+					if err := c.Collect(errfn("expected EOL, EOF, or comment")); err != nil {
+						return err
+					}
+				}
+			}
+			err := c.Collect(callback(sect, sectsub, n, v, blank))
+			if err != nil {
+				return err
+			}
+		default:
+			if sect == "" {
+				if err := c.Collect(errfn("expected section header")); err != nil {
+					return err
+				}
+			}
+			if err := c.Collect(errfn("expected section header or variable declaration")); err != nil {
+				return err
+			}
+		}
+	}
+	panic("never reached")
+}
+
+func readInto(config interface{}, fset *token.FileSet, file *token.File,
+	src []byte) error {
+	//
+	c := warnings.NewCollector(isFatal)
+	firstPassCallback := func(s string, ss string, k string, v string, bv bool) error {
+		return set(c, config, s, ss, k, v, bv, false)
+	}
+	err := read(c, firstPassCallback, fset, file, src)
+	if err != nil {
+		return err
+	}
+	secondPassCallback := func(s string, ss string, k string, v string, bv bool) error {
+		return set(c, config, s, ss, k, v, bv, true)
+	}
+	err = read(c, secondPassCallback, fset, file, src)
+	if err != nil {
+		return err
+	}
+	return c.Done()
+}
+
+// ReadWithCallback reads gcfg formatted data from reader and calls
+// callback with each section and option found.
+//
+// Callback is called with section, subsection, option key, option value
+// and blank value flag as arguments.
+//
+// When a section is found, callback is called with nil subsection, option key
+// and option value.
+//
+// When a subsection is found, callback is called with nil option key and
+// option value.
+//
+// If blank value flag is true, it means that the value was not set for an option
+// (as opposed to set to empty string).
+//
+// If callback returns an error, ReadWithCallback terminates with an error too.
+func ReadWithCallback(reader io.Reader, callback func(string, string, string, string, bool) error) error {
+	src, err := io.ReadAll(reader)
+	if err != nil {
+		return err
+	}
+
+	fset := token.NewFileSet()
+	file := fset.AddFile("", fset.Base(), len(src))
+	c := warnings.NewCollector(isFatal)
+
+	return read(c, callback, fset, file, src)
+}
+
+// ReadInto reads gcfg formatted data from reader and sets the values into the
+// corresponding fields in config.
+func ReadInto(config interface{}, reader io.Reader) error {
+	src, err := io.ReadAll(reader)
+	if err != nil {
+		return err
+	}
+	fset := token.NewFileSet()
+	file := fset.AddFile("", fset.Base(), len(src))
+	return readInto(config, fset, file, src)
+}
+
+// ReadStringInto reads gcfg formatted data from str and sets the values into
+// the corresponding fields in config.
+func ReadStringInto(config interface{}, str string) error {
+	r := strings.NewReader(str)
+	return ReadInto(config, r)
+}
+
+// ReadFileInto reads gcfg formatted data from the file filename and sets the
+// values into the corresponding fields in config.
+func ReadFileInto(config interface{}, filename string) error {
+	f, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	src, err := io.ReadAll(f)
+	if err != nil {
+		return err
+	}
+	fset := token.NewFileSet()
+	file := fset.AddFile(filename, fset.Base(), len(src))
+	return readInto(config, fset, file, src)
+}

vendor/github.com/go-git/gcfg/scanner/errors.go

@@ -0,0 +1,117 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package scanner
+
+import (
+	"fmt"
+	"io"
+	"sort"
+)
+
+import (
+	"github.com/go-git/gcfg/token"
+)
+
+// In an ErrorList, an error is represented by an *Error.
+// The position Pos, if valid, points to the beginning of
+// the offending token, and the error condition is described
+// by Msg.
+type Error struct {
+	Pos token.Position
+	Msg string
+}
+
+// Error implements the error interface.
+func (e Error) Error() string {
+	if e.Pos.Filename != "" || e.Pos.IsValid() {
+		// don't print "<unknown position>"
+		// TODO(gri) reconsider the semantics of Position.IsValid
+		return e.Pos.String() + ": " + e.Msg
+	}
+	return e.Msg
+}
+
+// ErrorList is a list of *Errors.
+// The zero value for an ErrorList is an empty ErrorList ready to use.
+type ErrorList []*Error
+
+// Add adds an Error with given position and error message to an ErrorList.
+func (p *ErrorList) Add(pos token.Position, msg string) {
+	*p = append(*p, &Error{pos, msg})
+}
+
+// Reset resets an ErrorList to no errors.
+func (p *ErrorList) Reset() { *p = (*p)[0:0] }
+
+// ErrorList implements the sort Interface.
+func (p ErrorList) Len() int      { return len(p) }
+func (p ErrorList) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
+
+func (p ErrorList) Less(i, j int) bool {
+	e := &p[i].Pos
+	f := &p[j].Pos
+	if e.Filename < f.Filename {
+		return true
+	}
+	if e.Filename == f.Filename {
+		return e.Offset < f.Offset
+	}
+	return false
+}
+
+// Sort sorts an ErrorList. *Error entries are sorted by position,
+// other errors are sorted by error message, and before any *Error
+// entry.
+func (p ErrorList) Sort() {
+	sort.Sort(p)
+}
+
+// RemoveMultiples sorts an ErrorList and removes all but the first error per line.
+func (p *ErrorList) RemoveMultiples() {
+	sort.Sort(p)
+	var last token.Position // initial last.Line is != any legal error line
+	i := 0
+	for _, e := range *p {
+		if e.Pos.Filename != last.Filename || e.Pos.Line != last.Line {
+			last = e.Pos
+			(*p)[i] = e
+			i++
+		}
+	}
+	(*p) = (*p)[0:i]
+}
+
+// An ErrorList implements the error interface.
+func (p ErrorList) Error() string {
+	switch len(p) {
+	case 0:
+		return "no errors"
+	case 1:
+		return p[0].Error()
+	}
+	return fmt.Sprintf("%s (and %d more errors)", p[0], len(p)-1)
+}
+
+// Err returns an error equivalent to this error list.
+// If the list is empty, Err returns nil.
+func (p ErrorList) Err() error {
+	if len(p) == 0 {
+		return nil
+	}
+	return p
+}
+
+// PrintError is a utility function that prints a list of errors to w,
+// one error per line, if the err parameter is an ErrorList. Otherwise
+// it prints the err string.
+func PrintError(w io.Writer, err error) {
+	if list, ok := err.(ErrorList); ok {
+		for _, e := range list {
+			fmt.Fprintf(w, "%s\n", e)
+		}
+	} else if err != nil {
+		fmt.Fprintf(w, "%s\n", err)
+	}
+}

vendor/github.com/go-git/gcfg/scanner/scanner.go

@@ -0,0 +1,334 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package scanner implements a scanner for gcfg configuration text.
+// It takes a []byte as source which can then be tokenized
+// through repeated calls to the Scan method.
+//
+// Note that the API for the scanner package may change to accommodate new
+// features or implementation changes in gcfg.
+package scanner
+
+import (
+	"fmt"
+	"path/filepath"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/go-git/gcfg/token"
+)
+
+// An ErrorHandler may be provided to Scanner.Init. If a syntax error is
+// encountered and a handler was installed, the handler is called with a
+// position and an error message. The position points to the beginning of
+// the offending token.
+type ErrorHandler func(pos token.Position, msg string)
+
+// A Scanner holds the scanner's internal state while processing
+// a given text.  It can be allocated as part of another data
+// structure but must be initialized via Init before use.
+type Scanner struct {
+	// immutable state
+	file *token.File  // source file handle
+	dir  string       // directory portion of file.Name()
+	src  []byte       // source
+	err  ErrorHandler // error reporting; or nil
+	mode Mode         // scanning mode
+
+	// scanning state
+	ch         rune // current character
+	offset     int  // character offset
+	rdOffset   int  // reading offset (position after current character)
+	lineOffset int  // current line offset
+	nextVal    bool // next token is expected to be a value
+
+	// public state - ok to modify
+	ErrorCount int // number of errors encountered
+}
+
+// Read the next Unicode char into s.ch.
+// s.ch < 0 means end-of-file.
+func (s *Scanner) next() {
+	if s.rdOffset < len(s.src) {
+		s.offset = s.rdOffset
+		if s.ch == '\n' {
+			s.lineOffset = s.offset
+			s.file.AddLine(s.offset)
+		}
+		r, w := rune(s.src[s.rdOffset]), 1
+		switch {
+		case r == 0:
+			s.error(s.offset, "illegal character NUL")
+		case r >= 0x80:
+			// not ASCII
+			r, w = utf8.DecodeRune(s.src[s.rdOffset:])
+			if r == utf8.RuneError && w == 1 {
+				s.error(s.offset, "illegal UTF-8 encoding")
+			}
+		}
+		s.rdOffset += w
+		s.ch = r
+	} else {
+		s.offset = len(s.src)
+		if s.ch == '\n' {
+			s.lineOffset = s.offset
+			s.file.AddLine(s.offset)
+		}
+		s.ch = -1 // eof
+	}
+}
+
+// A mode value is a set of flags (or 0).
+// They control scanner behavior.
+type Mode uint
+
+const (
+	ScanComments Mode = 1 << iota // return comments as COMMENT tokens
+)
+
+// Init prepares the scanner s to tokenize the text src by setting the
+// scanner at the beginning of src. The scanner uses the file set file
+// for position information and it adds line information for each line.
+// It is ok to re-use the same file when re-scanning the same file as
+// line information which is already present is ignored. Init causes a
+// panic if the file size does not match the src size.
+//
+// Calls to Scan will invoke the error handler err if they encounter a
+// syntax error and err is not nil. Also, for each error encountered,
+// the Scanner field ErrorCount is incremented by one. The mode parameter
+// determines how comments are handled.
+//
+// Note that Init may call err if there is an error in the first character
+// of the file.
+func (s *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode Mode) {
+	// Explicitly initialize all fields since a scanner may be reused.
+	if file.Size() != len(src) {
+		panic(fmt.Sprintf("file size (%d) does not match src len (%d)", file.Size(), len(src)))
+	}
+	s.file = file
+	s.dir, _ = filepath.Split(file.Name())
+	s.src = src
+	s.err = err
+	s.mode = mode
+
+	s.ch = ' '
+	s.offset = 0
+	s.rdOffset = 0
+	s.lineOffset = 0
+	s.ErrorCount = 0
+	s.nextVal = false
+
+	s.next()
+}
+
+func (s *Scanner) error(offs int, msg string) {
+	if s.err != nil {
+		s.err(s.file.Position(s.file.Pos(offs)), msg)
+	}
+	s.ErrorCount++
+}
+
+func (s *Scanner) scanComment() string {
+	// initial [;#] already consumed
+	offs := s.offset - 1 // position of initial [;#]
+
+	for s.ch != '\n' && s.ch >= 0 {
+		s.next()
+	}
+	return string(s.src[offs:s.offset])
+}
+
+func isLetter(ch rune) bool {
+	return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch >= 0x80 && unicode.IsLetter(ch)
+}
+
+func isDigit(ch rune) bool {
+	return '0' <= ch && ch <= '9' || ch >= 0x80 && unicode.IsDigit(ch)
+}
+
+func (s *Scanner) scanIdentifier() string {
+	offs := s.offset
+	for isLetter(s.ch) || isDigit(s.ch) || s.ch == '-' {
+		s.next()
+	}
+	return string(s.src[offs:s.offset])
+}
+
+// val indicate if we are scanning a value (vs a header)
+func (s *Scanner) scanEscape(val bool) {
+	offs := s.offset
+	ch := s.ch
+	s.next() // always make progress
+	switch ch {
+	case '\\', '"', '\n':
+		// ok
+	case 'n', 't', 'b':
+		if val {
+			break // ok
+		}
+		fallthrough
+	default:
+		s.error(offs, "unknown escape sequence")
+	}
+}
+
+func (s *Scanner) scanString() string {
+	// '"' opening already consumed
+	offs := s.offset - 1
+
+	for s.ch != '"' {
+		ch := s.ch
+		s.next()
+		if ch == '\n' || ch < 0 {
+			s.error(offs, "string not terminated")
+			break
+		}
+		if ch == '\\' {
+			s.scanEscape(false)
+		}
+	}
+
+	s.next()
+
+	return string(s.src[offs:s.offset])
+}
+
+func stripCR(b []byte) []byte {
+	c := make([]byte, len(b))
+	i := 0
+	for _, ch := range b {
+		if ch != '\r' {
+			c[i] = ch
+			i++
+		}
+	}
+	return c[:i]
+}
+
+func (s *Scanner) scanValString() string {
+	offs := s.offset
+
+	hasCR := false
+	end := offs
+	inQuote := false
+loop:
+	for inQuote || s.ch >= 0 && s.ch != '\n' && s.ch != ';' && s.ch != '#' {
+		ch := s.ch
+		s.next()
+		switch {
+		case inQuote && ch == '\\':
+			s.scanEscape(true)
+		case !inQuote && ch == '\\':
+			if s.ch == '\r' {
+				hasCR = true
+				s.next()
+			}
+			if s.ch != '\n' {
+				s.scanEscape(true)
+			} else {
+				s.next()
+			}
+		case ch == '"':
+			inQuote = !inQuote
+		case ch == '\r':
+			hasCR = true
+		case ch < 0 || inQuote && ch == '\n':
+			s.error(offs, "string not terminated")
+			break loop
+		}
+		if inQuote || !isWhiteSpace(ch) {
+			end = s.offset
+		}
+	}
+
+	lit := s.src[offs:end]
+	if hasCR {
+		lit = stripCR(lit)
+	}
+
+	return string(lit)
+}
+
+func isWhiteSpace(ch rune) bool {
+	return ch == ' ' || ch == '\t' || ch == '\r'
+}
+
+func (s *Scanner) skipWhitespace() {
+	for isWhiteSpace(s.ch) {
+		s.next()
+	}
+}
+
+// Scan scans the next token and returns the token position, the token,
+// and its literal string if applicable. The source end is indicated by
+// token.EOF.
+//
+// If the returned token is a literal (token.IDENT, token.STRING) or
+// token.COMMENT, the literal string has the corresponding value.
+//
+// If the returned token is token.ILLEGAL, the literal string is the
+// offending character.
+//
+// In all other cases, Scan returns an empty literal string.
+//
+// For more tolerant parsing, Scan will return a valid token if
+// possible even if a syntax error was encountered. Thus, even
+// if the resulting token sequence contains no illegal tokens,
+// a client may not assume that no error occurred. Instead it
+// must check the scanner's ErrorCount or the number of calls
+// of the error handler, if there was one installed.
+//
+// Scan adds line information to the file added to the file
+// set with Init. Token positions are relative to that file
+// and thus relative to the file set.
+func (s *Scanner) Scan() (pos token.Pos, tok token.Token, lit string) {
+scanAgain:
+	s.skipWhitespace()
+
+	// current token start
+	pos = s.file.Pos(s.offset)
+
+	// determine token value
+	switch ch := s.ch; {
+	case s.nextVal:
+		lit = s.scanValString()
+		tok = token.STRING
+		s.nextVal = false
+	case isLetter(ch):
+		lit = s.scanIdentifier()
+		tok = token.IDENT
+	default:
+		s.next() // always make progress
+		switch ch {
+		case -1:
+			tok = token.EOF
+		case '\n':
+			tok = token.EOL
+		case '"':
+			tok = token.STRING
+			lit = s.scanString()
+		case '[':
+			tok = token.LBRACK
+		case ']':
+			tok = token.RBRACK
+		case ';', '#':
+			// comment
+			lit = s.scanComment()
+			if s.mode&ScanComments == 0 {
+				// skip comment
+				goto scanAgain
+			}
+			tok = token.COMMENT
+		case '=':
+			tok = token.ASSIGN
+			s.nextVal = true
+		default:
+			s.error(s.file.Offset(pos), fmt.Sprintf("illegal character %#U", ch))
+			tok = token.ILLEGAL
+			lit = string(ch)
+		}
+	}
+
+	return
+}

vendor/github.com/go-git/gcfg/set.go

@@ -0,0 +1,334 @@
+package gcfg
+
+import (
+	"bytes"
+	"encoding"
+	"encoding/gob"
+	"fmt"
+	"math/big"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"gopkg.in/warnings.v0"
+
+	"github.com/go-git/gcfg/types"
+)
+
+type tag struct {
+	ident   string
+	intMode string
+}
+
+func newTag(ts string) tag {
+	t := tag{}
+	s := strings.Split(ts, ",")
+	t.ident = s[0]
+	for _, tse := range s[1:] {
+		if strings.HasPrefix(tse, "int=") {
+			t.intMode = tse[len("int="):]
+		}
+	}
+	return t
+}
+
+func fieldFold(v reflect.Value, name string) (reflect.Value, tag) {
+	var n string
+	r0, _ := utf8.DecodeRuneInString(name)
+	if unicode.IsLetter(r0) && !unicode.IsLower(r0) && !unicode.IsUpper(r0) {
+		n = "X"
+	}
+	n += strings.Replace(name, "-", "_", -1)
+	f, ok := v.Type().FieldByNameFunc(func(fieldName string) bool {
+		if !v.FieldByName(fieldName).CanSet() {
+			return false
+		}
+		f, _ := v.Type().FieldByName(fieldName)
+		t := newTag(f.Tag.Get("gcfg"))
+		if t.ident != "" {
+			return strings.EqualFold(t.ident, name)
+		}
+		return strings.EqualFold(n, fieldName)
+	})
+	if !ok {
+		return reflect.Value{}, tag{}
+	}
+	return v.FieldByName(f.Name), newTag(f.Tag.Get("gcfg"))
+}
+
+type setter func(destp interface{}, blank bool, val string, t tag) error
+
+var errUnsupportedType = fmt.Errorf("unsupported type")
+var errBlankUnsupported = fmt.Errorf("blank value not supported for type")
+
+var setters = []setter{
+	typeSetter, textUnmarshalerSetter, kindSetter, scanSetter,
+}
+
+func textUnmarshalerSetter(d interface{}, blank bool, val string, t tag) error {
+	dtu, ok := d.(encoding.TextUnmarshaler)
+	if !ok {
+		return errUnsupportedType
+	}
+	if blank {
+		return errBlankUnsupported
+	}
+	return dtu.UnmarshalText([]byte(val))
+}
+
+func boolSetter(d interface{}, blank bool, val string, t tag) error {
+	if blank {
+		reflect.ValueOf(d).Elem().Set(reflect.ValueOf(true))
+		return nil
+	}
+	b, err := types.ParseBool(val)
+	if err == nil {
+		reflect.ValueOf(d).Elem().Set(reflect.ValueOf(b))
+	}
+	return err
+}
+
+func intMode(mode string) types.IntMode {
+	var m types.IntMode
+	if strings.ContainsAny(mode, "dD") {
+		m |= types.Dec
+	}
+	if strings.ContainsAny(mode, "hH") {
+		m |= types.Hex
+	}
+	if strings.ContainsAny(mode, "oO") {
+		m |= types.Oct
+	}
+	return m
+}
+
+var typeModes = map[reflect.Type]types.IntMode{
+	reflect.TypeOf(int(0)):    types.Dec | types.Hex,
+	reflect.TypeOf(int8(0)):   types.Dec | types.Hex,
+	reflect.TypeOf(int16(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(int32(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(int64(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(uint(0)):   types.Dec | types.Hex,
+	reflect.TypeOf(uint8(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(uint16(0)): types.Dec | types.Hex,
+	reflect.TypeOf(uint32(0)): types.Dec | types.Hex,
+	reflect.TypeOf(uint64(0)): types.Dec | types.Hex,
+	// use default mode (allow dec/hex/oct) for uintptr type
+	reflect.TypeOf(big.Int{}): types.Dec | types.Hex,
+}
+
+func intModeDefault(t reflect.Type) types.IntMode {
+	m, ok := typeModes[t]
+	if !ok {
+		m = types.Dec | types.Hex | types.Oct
+	}
+	return m
+}
+
+func intSetter(d interface{}, blank bool, val string, t tag) error {
+	if blank {
+		return errBlankUnsupported
+	}
+	mode := intMode(t.intMode)
+	if mode == 0 {
+		mode = intModeDefault(reflect.TypeOf(d).Elem())
+	}
+	return types.ParseInt(d, val, mode)
+}
+
+func stringSetter(d interface{}, blank bool, val string, t tag) error {
+	if blank {
+		return errBlankUnsupported
+	}
+	dsp, ok := d.(*string)
+	if !ok {
+		return errUnsupportedType
+	}
+	*dsp = val
+	return nil
+}
+
+var kindSetters = map[reflect.Kind]setter{
+	reflect.String:  stringSetter,
+	reflect.Bool:    boolSetter,
+	reflect.Int:     intSetter,
+	reflect.Int8:    intSetter,
+	reflect.Int16:   intSetter,
+	reflect.Int32:   intSetter,
+	reflect.Int64:   intSetter,
+	reflect.Uint:    intSetter,
+	reflect.Uint8:   intSetter,
+	reflect.Uint16:  intSetter,
+	reflect.Uint32:  intSetter,
+	reflect.Uint64:  intSetter,
+	reflect.Uintptr: intSetter,
+}
+
+var typeSetters = map[reflect.Type]setter{
+	reflect.TypeOf(big.Int{}): intSetter,
+}
+
+func typeSetter(d interface{}, blank bool, val string, tt tag) error {
+	t := reflect.ValueOf(d).Type().Elem()
+	setter, ok := typeSetters[t]
+	if !ok {
+		return errUnsupportedType
+	}
+	return setter(d, blank, val, tt)
+}
+
+func kindSetter(d interface{}, blank bool, val string, tt tag) error {
+	k := reflect.ValueOf(d).Type().Elem().Kind()
+	setter, ok := kindSetters[k]
+	if !ok {
+		return errUnsupportedType
+	}
+	return setter(d, blank, val, tt)
+}
+
+func scanSetter(d interface{}, blank bool, val string, tt tag) error {
+	if blank {
+		return errBlankUnsupported
+	}
+	return types.ScanFully(d, val, 'v')
+}
+
+func newValue(c *warnings.Collector, sect string, vCfg reflect.Value,
+	vType reflect.Type) (reflect.Value, error) {
+	//
+	pv := reflect.New(vType)
+	dfltName := "default-" + sect
+	dfltField, _ := fieldFold(vCfg, dfltName)
+	var err error
+	if dfltField.IsValid() {
+		b := bytes.NewBuffer(nil)
+		ge := gob.NewEncoder(b)
+		if err = c.Collect(ge.EncodeValue(dfltField)); err != nil {
+			return pv, err
+		}
+		gd := gob.NewDecoder(bytes.NewReader(b.Bytes()))
+		if err = c.Collect(gd.DecodeValue(pv.Elem())); err != nil {
+			return pv, err
+		}
+	}
+	return pv, nil
+}
+
+func set(c *warnings.Collector, cfg interface{}, sect, sub, name string,
+	value string, blankValue bool, subsectPass bool) error {
+	//
+	vPCfg := reflect.ValueOf(cfg)
+	if vPCfg.Kind() != reflect.Ptr || vPCfg.Elem().Kind() != reflect.Struct {
+		panic(fmt.Errorf("config must be a pointer to a struct"))
+	}
+	vCfg := vPCfg.Elem()
+	vSect, _ := fieldFold(vCfg, sect)
+	if !vSect.IsValid() {
+		err := extraData{section: sect}
+		return c.Collect(err)
+	}
+	isSubsect := vSect.Kind() == reflect.Map
+	if subsectPass != isSubsect {
+		return nil
+	}
+	if isSubsect {
+		vst := vSect.Type()
+		if vst.Key().Kind() != reflect.String ||
+			vst.Elem().Kind() != reflect.Ptr ||
+			vst.Elem().Elem().Kind() != reflect.Struct {
+			panic(fmt.Errorf("map field for section must have string keys and "+
+				" pointer-to-struct values: section %q", sect))
+		}
+		if vSect.IsNil() {
+			vSect.Set(reflect.MakeMap(vst))
+		}
+		k := reflect.ValueOf(sub)
+		pv := vSect.MapIndex(k)
+		if !pv.IsValid() {
+			vType := vSect.Type().Elem().Elem()
+			var err error
+			if pv, err = newValue(c, sect, vCfg, vType); err != nil {
+				return err
+			}
+			vSect.SetMapIndex(k, pv)
+		}
+		vSect = pv.Elem()
+	} else if vSect.Kind() != reflect.Struct {
+		panic(fmt.Errorf("field for section must be a map or a struct: "+
+			"section %q", sect))
+	} else if sub != "" {
+		err := extraData{section: sect, subsection: &sub}
+		return c.Collect(err)
+	}
+	// Empty name is a special value, meaning that only the
+	// section/subsection object is to be created, with no values set.
+	if name == "" {
+		return nil
+	}
+	vVar, t := fieldFold(vSect, name)
+	if !vVar.IsValid() {
+		var err error
+		if isSubsect {
+			err = extraData{section: sect, subsection: &sub, variable: &name}
+		} else {
+			err = extraData{section: sect, variable: &name}
+		}
+		return c.Collect(err)
+	}
+	// vVal is either single-valued var, or newly allocated value within multi-valued var
+	var vVal reflect.Value
+	// multi-value if unnamed slice type
+	isMulti := vVar.Type().Name() == "" && vVar.Kind() == reflect.Slice ||
+		vVar.Type().Name() == "" && vVar.Kind() == reflect.Ptr && vVar.Type().Elem().Name() == "" && vVar.Type().Elem().Kind() == reflect.Slice
+	if isMulti && vVar.Kind() == reflect.Ptr {
+		if vVar.IsNil() {
+			vVar.Set(reflect.New(vVar.Type().Elem()))
+		}
+		vVar = vVar.Elem()
+	}
+	if isMulti && blankValue {
+		vVar.Set(reflect.Zero(vVar.Type()))
+		return nil
+	}
+	if isMulti {
+		vVal = reflect.New(vVar.Type().Elem()).Elem()
+	} else {
+		vVal = vVar
+	}
+	isDeref := vVal.Type().Name() == "" && vVal.Type().Kind() == reflect.Ptr
+	isNew := isDeref && vVal.IsNil()
+	// vAddr is address of value to set (dereferenced & allocated as needed)
+	var vAddr reflect.Value
+	switch {
+	case isNew:
+		vAddr = reflect.New(vVal.Type().Elem())
+	case isDeref && !isNew:
+		vAddr = vVal
+	default:
+		vAddr = vVal.Addr()
+	}
+	vAddrI := vAddr.Interface()
+	err, ok := error(nil), false
+	for _, s := range setters {
+		err = s(vAddrI, blankValue, value, t)
+		if err == nil {
+			ok = true
+			break
+		}
+		if err != errUnsupportedType {
+			return err
+		}
+	}
+	if !ok {
+		// in case all setters returned errUnsupportedType
+		return err
+	}
+	if isNew { // set reference if it was dereferenced and newly allocated
+		vVal.Set(vAddr)
+	}
+	if isMulti { // append if multi-valued
+		vVar.Set(reflect.Append(vVar, vVal))
+	}
+	return nil
+}

vendor/github.com/go-git/gcfg/token/position.go

@@ -0,0 +1,418 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// TODO(gri) consider making this a separate package outside the go directory.
+
+package token
+
+import (
+	"fmt"
+	"sort"
+	"sync"
+)
+
+// -----------------------------------------------------------------------------
+// Positions
+
+// Position describes an arbitrary source position
+// including the file, line, and column location.
+// A Position is valid if the line number is > 0.
+type Position struct {
+	Filename string // filename, if any
+	Offset   int    // offset, starting at 0
+	Line     int    // line number, starting at 1
+	Column   int    // column number, starting at 1 (character count)
+}
+
+// IsValid returns true if the position is valid.
+func (pos *Position) IsValid() bool { return pos.Line > 0 }
+
+// String returns a string in one of several forms:
+//
+//	file:line:column    valid position with file name
+//	line:column         valid position without file name
+//	file                invalid position with file name
+//	-                   invalid position without file name
+func (pos Position) String() string {
+	s := pos.Filename
+	if pos.IsValid() {
+		if s != "" {
+			s += ":"
+		}
+		s += fmt.Sprintf("%d:%d", pos.Line, pos.Column)
+	}
+	if s == "" {
+		s = "-"
+	}
+	return s
+}
+
+// Pos is a compact encoding of a source position within a file set.
+// It can be converted into a Position for a more convenient, but much
+// larger, representation.
+//
+// The Pos value for a given file is a number in the range [base, base+size],
+// where base and size are specified when adding the file to the file set via
+// AddFile.
+//
+// To create the Pos value for a specific source offset, first add
+// the respective file to the current file set (via FileSet.AddFile)
+// and then call File.Pos(offset) for that file. Given a Pos value p
+// for a specific file set fset, the corresponding Position value is
+// obtained by calling fset.Position(p).
+//
+// Pos values can be compared directly with the usual comparison operators:
+// If two Pos values p and q are in the same file, comparing p and q is
+// equivalent to comparing the respective source file offsets. If p and q
+// are in different files, p < q is true if the file implied by p was added
+// to the respective file set before the file implied by q.
+type Pos int
+
+// The zero value for Pos is NoPos; there is no file and line information
+// associated with it, and NoPos().IsValid() is false. NoPos is always
+// smaller than any other Pos value. The corresponding Position value
+// for NoPos is the zero value for Position.
+const NoPos Pos = 0
+
+// IsValid returns true if the position is valid.
+func (p Pos) IsValid() bool {
+	return p != NoPos
+}
+
+// -----------------------------------------------------------------------------
+// File
+
+// A File is a handle for a file belonging to a FileSet.
+// A File has a name, size, and line offset table.
+type File struct {
+	set  *FileSet
+	name string // file name as provided to AddFile
+	base int    // Pos value range for this file is [base...base+size]
+	size int    // file size as provided to AddFile
+
+	// lines and infos are protected by set.mutex
+	lines []int
+	infos []lineInfo
+}
+
+// Name returns the file name of file f as registered with AddFile.
+func (f *File) Name() string {
+	return f.name
+}
+
+// Base returns the base offset of file f as registered with AddFile.
+func (f *File) Base() int {
+	return f.base
+}
+
+// Size returns the size of file f as registered with AddFile.
+func (f *File) Size() int {
+	return f.size
+}
+
+// LineCount returns the number of lines in file f.
+func (f *File) LineCount() int {
+	f.set.mutex.RLock()
+	n := len(f.lines)
+	f.set.mutex.RUnlock()
+	return n
+}
+
+// AddLine adds the line offset for a new line.
+// The line offset must be larger than the offset for the previous line
+// and smaller than the file size; otherwise the line offset is ignored.
+func (f *File) AddLine(offset int) {
+	f.set.mutex.Lock()
+	if i := len(f.lines); (i == 0 || f.lines[i-1] < offset) && offset < f.size {
+		f.lines = append(f.lines, offset)
+	}
+	f.set.mutex.Unlock()
+}
+
+// SetLines sets the line offsets for a file and returns true if successful.
+// The line offsets are the offsets of the first character of each line;
+// for instance for the content "ab\nc\n" the line offsets are {0, 3}.
+// An empty file has an empty line offset table.
+// Each line offset must be larger than the offset for the previous line
+// and smaller than the file size; otherwise SetLines fails and returns
+// false.
+func (f *File) SetLines(lines []int) bool {
+	// verify validity of lines table
+	size := f.size
+	for i, offset := range lines {
+		if i > 0 && offset <= lines[i-1] || size <= offset {
+			return false
+		}
+	}
+
+	// set lines table
+	f.set.mutex.Lock()
+	f.lines = lines
+	f.set.mutex.Unlock()
+	return true
+}
+
+// SetLinesForContent sets the line offsets for the given file content.
+func (f *File) SetLinesForContent(content []byte) {
+	var lines []int
+	line := 0
+	for offset, b := range content {
+		if line >= 0 {
+			lines = append(lines, line)
+		}
+		line = -1
+		if b == '\n' {
+			line = offset + 1
+		}
+	}
+
+	// set lines table
+	f.set.mutex.Lock()
+	f.lines = lines
+	f.set.mutex.Unlock()
+}
+
+// A lineInfo object describes alternative file and line number
+// information (such as provided via a //line comment in a .go
+// file) for a given file offset.
+type lineInfo struct {
+	// fields are exported to make them accessible to gob
+	Offset   int
+	Filename string
+	Line     int
+}
+
+// AddLineInfo adds alternative file and line number information for
+// a given file offset. The offset must be larger than the offset for
+// the previously added alternative line info and smaller than the
+// file size; otherwise the information is ignored.
+//
+// AddLineInfo is typically used to register alternative position
+// information for //line filename:line comments in source files.
+func (f *File) AddLineInfo(offset int, filename string, line int) {
+	f.set.mutex.Lock()
+	if i := len(f.infos); i == 0 || f.infos[i-1].Offset < offset && offset < f.size {
+		f.infos = append(f.infos, lineInfo{offset, filename, line})
+	}
+	f.set.mutex.Unlock()
+}
+
+// Pos returns the Pos value for the given file offset;
+// the offset must be <= f.Size().
+// f.Pos(f.Offset(p)) == p.
+func (f *File) Pos(offset int) Pos {
+	if offset > f.size {
+		panic("illegal file offset")
+	}
+	return Pos(f.base + offset)
+}
+
+// Offset returns the offset for the given file position p;
+// p must be a valid Pos value in that file.
+// f.Offset(f.Pos(offset)) == offset.
+func (f *File) Offset(p Pos) int {
+	if int(p) < f.base || int(p) > f.base+f.size {
+		panic("illegal Pos value")
+	}
+	return int(p) - f.base
+}
+
+// Line returns the line number for the given file position p;
+// p must be a Pos value in that file or NoPos.
+func (f *File) Line(p Pos) int {
+	// TODO(gri) this can be implemented much more efficiently
+	return f.Position(p).Line
+}
+
+func searchLineInfos(a []lineInfo, x int) int {
+	return sort.Search(len(a), func(i int) bool { return a[i].Offset > x }) - 1
+}
+
+// info returns the file name, line, and column number for a file offset.
+func (f *File) info(offset int) (filename string, line, column int) {
+	filename = f.name
+	if i := searchInts(f.lines, offset); i >= 0 {
+		line, column = i+1, offset-f.lines[i]+1
+	}
+	if len(f.infos) > 0 {
+		// almost no files have extra line infos
+		if i := searchLineInfos(f.infos, offset); i >= 0 {
+			alt := &f.infos[i]
+			filename = alt.Filename
+			if i := searchInts(f.lines, alt.Offset); i >= 0 {
+				line += alt.Line - i - 1
+			}
+		}
+	}
+	return
+}
+
+func (f *File) position(p Pos) (pos Position) {
+	offset := int(p) - f.base
+	pos.Offset = offset
+	pos.Filename, pos.Line, pos.Column = f.info(offset)
+	return
+}
+
+// Position returns the Position value for the given file position p;
+// p must be a Pos value in that file or NoPos.
+func (f *File) Position(p Pos) (pos Position) {
+	if p != NoPos {
+		if int(p) < f.base || int(p) > f.base+f.size {
+			panic("illegal Pos value")
+		}
+		pos = f.position(p)
+	}
+	return
+}
+
+// -----------------------------------------------------------------------------
+// FileSet
+
+// A FileSet represents a set of source files.
+// Methods of file sets are synchronized; multiple goroutines
+// may invoke them concurrently.
+type FileSet struct {
+	mutex sync.RWMutex // protects the file set
+	base  int          // base offset for the next file
+	files []*File      // list of files in the order added to the set
+	last  *File        // cache of last file looked up
+}
+
+// NewFileSet creates a new file set.
+func NewFileSet() *FileSet {
+	s := new(FileSet)
+	s.base = 1 // 0 == NoPos
+	return s
+}
+
+// Base returns the minimum base offset that must be provided to
+// AddFile when adding the next file.
+func (s *FileSet) Base() int {
+	s.mutex.RLock()
+	b := s.base
+	s.mutex.RUnlock()
+	return b
+
+}
+
+// AddFile adds a new file with a given filename, base offset, and file size
+// to the file set s and returns the file. Multiple files may have the same
+// name. The base offset must not be smaller than the FileSet's Base(), and
+// size must not be negative.
+//
+// Adding the file will set the file set's Base() value to base + size + 1
+// as the minimum base value for the next file. The following relationship
+// exists between a Pos value p for a given file offset offs:
+//
+//	int(p) = base + offs
+//
+// with offs in the range [0, size] and thus p in the range [base, base+size].
+// For convenience, File.Pos may be used to create file-specific position
+// values from a file offset.
+func (s *FileSet) AddFile(filename string, base, size int) *File {
+	s.mutex.Lock()
+	defer s.mutex.Unlock()
+	if base < s.base || size < 0 {
+		panic("illegal base or size")
+	}
+	// base >= s.base && size >= 0
+	f := &File{s, filename, base, size, []int{0}, nil}
+	base += size + 1 // +1 because EOF also has a position
+	if base < 0 {
+		panic("token.Pos offset overflow (> 2G of source code in file set)")
+	}
+	// add the file to the file set
+	s.base = base
+	s.files = append(s.files, f)
+	s.last = f
+	return f
+}
+
+// Iterate calls f for the files in the file set in the order they were added
+// until f returns false.
+func (s *FileSet) Iterate(f func(*File) bool) {
+	for i := 0; ; i++ {
+		var file *File
+		s.mutex.RLock()
+		if i < len(s.files) {
+			file = s.files[i]
+		}
+		s.mutex.RUnlock()
+		if file == nil || !f(file) {
+			break
+		}
+	}
+}
+
+func searchFiles(a []*File, x int) int {
+	return sort.Search(len(a), func(i int) bool { return a[i].base > x }) - 1
+}
+
+func (s *FileSet) file(p Pos) *File {
+	// common case: p is in last file
+	if f := s.last; f != nil && f.base <= int(p) && int(p) <= f.base+f.size {
+		return f
+	}
+	// p is not in last file - search all files
+	if i := searchFiles(s.files, int(p)); i >= 0 {
+		f := s.files[i]
+		// f.base <= int(p) by definition of searchFiles
+		if int(p) <= f.base+f.size {
+			s.last = f
+			return f
+		}
+	}
+	return nil
+}
+
+// File returns the file that contains the position p.
+// If no such file is found (for instance for p == NoPos),
+// the result is nil.
+func (s *FileSet) File(p Pos) (f *File) {
+	if p != NoPos {
+		s.mutex.RLock()
+		f = s.file(p)
+		s.mutex.RUnlock()
+	}
+	return
+}
+
+// Position converts a Pos in the fileset into a general Position.
+func (s *FileSet) Position(p Pos) (pos Position) {
+	if p != NoPos {
+		s.mutex.RLock()
+		if f := s.file(p); f != nil {
+			pos = f.position(p)
+		}
+		s.mutex.RUnlock()
+	}
+	return
+}
+
+// -----------------------------------------------------------------------------
+// Helper functions
+
+func searchInts(a []int, x int) int {
+	// This function body is a manually inlined version of:
+	//
+	//   return sort.Search(len(a), func(i int) bool { return a[i] > x }) - 1
+	//
+	// With better compiler optimizations, this may not be needed in the
+	// future, but at the moment this change improves the go/printer
+	// benchmark performance by ~30%. This has a direct impact on the
+	// speed of gofmt and thus seems worthwhile (2011-04-29).
+	// TODO(gri): Remove this when compilers have caught up.
+	i, j := 0, len(a)
+	for i < j {
+		h := i + (j-i)/2 // avoid overflow when computing h
+		// i ≤ h < j
+		if a[h] <= x {
+			i = h + 1
+		} else {
+			j = h
+		}
+	}
+	return i - 1
+}

vendor/github.com/go-git/gcfg/token/serialize.go

@@ -0,0 +1,56 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package token
+
+type serializedFile struct {
+	// fields correspond 1:1 to fields with same (lower-case) name in File
+	Name  string
+	Base  int
+	Size  int
+	Lines []int
+	Infos []lineInfo
+}
+
+type serializedFileSet struct {
+	Base  int
+	Files []serializedFile
+}
+
+// Read calls decode to deserialize a file set into s; s must not be nil.
+func (s *FileSet) Read(decode func(interface{}) error) error {
+	var ss serializedFileSet
+	if err := decode(&ss); err != nil {
+		return err
+	}
+
+	s.mutex.Lock()
+	s.base = ss.Base
+	files := make([]*File, len(ss.Files))
+	for i := 0; i < len(ss.Files); i++ {
+		f := &ss.Files[i]
+		files[i] = &File{s, f.Name, f.Base, f.Size, f.Lines, f.Infos}
+	}
+	s.files = files
+	s.last = nil
+	s.mutex.Unlock()
+
+	return nil
+}
+
+// Write calls encode to serialize the file set s.
+func (s *FileSet) Write(encode func(interface{}) error) error {
+	var ss serializedFileSet
+
+	s.mutex.Lock()
+	ss.Base = s.base
+	files := make([]serializedFile, len(s.files))
+	for i, f := range s.files {
+		files[i] = serializedFile{f.name, f.base, f.size, f.lines, f.infos}
+	}
+	ss.Files = files
+	s.mutex.Unlock()
+
+	return encode(ss)
+}

vendor/github.com/go-git/gcfg/token/token.go

@@ -0,0 +1,79 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package token defines constants representing the lexical tokens of the gcfg
+// configuration syntax and basic operations on tokens (printing, predicates).
+//
+// Note that the API for the token package may change to accommodate new
+// features or implementation changes in gcfg.
+package token
+
+import "strconv"
+
+// Token is the set of lexical tokens of the gcfg configuration syntax.
+type Token int
+
+// The list of tokens.
+const (
+	// Special tokens
+	ILLEGAL Token = iota
+	EOF
+	COMMENT
+
+	literal_beg
+	// Identifiers and basic type literals
+	// (these tokens stand for classes of literals)
+	IDENT  // section-name, variable-name
+	STRING // "subsection-name", variable value
+	literal_end
+
+	operator_beg
+	// Operators and delimiters
+	ASSIGN // =
+	LBRACK // [
+	RBRACK // ]
+	EOL    // \n
+	operator_end
+)
+
+var tokens = [...]string{
+	ILLEGAL: "ILLEGAL",
+
+	EOF:     "EOF",
+	COMMENT: "COMMENT",
+
+	IDENT:  "IDENT",
+	STRING: "STRING",
+
+	ASSIGN: "=",
+	LBRACK: "[",
+	RBRACK: "]",
+	EOL:    "\n",
+}
+
+// String returns the string corresponding to the token tok.
+// For operators and delimiters, the string is the actual token character
+// sequence (e.g., for the token ASSIGN, the string is "="). For all other
+// tokens the string corresponds to the token constant name (e.g. for the
+// token IDENT, the string is "IDENT").
+func (tok Token) String() string {
+	s := ""
+	if 0 <= tok && tok < Token(len(tokens)) {
+		s = tokens[tok]
+	}
+	if s == "" {
+		s = "token(" + strconv.Itoa(int(tok)) + ")"
+	}
+	return s
+}
+
+// Predicates
+
+// IsLiteral returns true for tokens corresponding to identifiers
+// and basic type literals; it returns false otherwise.
+func (tok Token) IsLiteral() bool { return literal_beg < tok && tok < literal_end }
+
+// IsOperator returns true for tokens corresponding to operators and
+// delimiters; it returns false otherwise.
+func (tok Token) IsOperator() bool { return operator_beg < tok && tok < operator_end }

vendor/github.com/go-git/gcfg/types/bool.go

@@ -0,0 +1,23 @@
+package types
+
+// BoolValues defines the name and value mappings for ParseBool.
+var BoolValues = map[string]interface{}{
+	"true": true, "yes": true, "on": true, "1": true,
+	"false": false, "no": false, "off": false, "0": false,
+}
+
+var boolParser = func() *EnumParser {
+	ep := &EnumParser{}
+	ep.AddVals(BoolValues)
+	return ep
+}()
+
+// ParseBool parses bool values according to the definitions in BoolValues.
+// Parsing is case-insensitive.
+func ParseBool(s string) (bool, error) {
+	v, err := boolParser.Parse(s)
+	if err != nil {
+		return false, err
+	}
+	return v.(bool), nil
+}

vendor/github.com/go-git/gcfg/types/doc.go

@@ -0,0 +1,4 @@
+// Package types defines helpers for type conversions.
+//
+// The API for this package is not finalized yet.
+package types

vendor/github.com/go-git/gcfg/types/enum.go

@@ -0,0 +1,44 @@
+package types
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// EnumParser parses "enum" values; i.e. a predefined set of strings to
+// predefined values.
+type EnumParser struct {
+	Type      string // type name; if not set, use type of first value added
+	CaseMatch bool   // if true, matching of strings is case-sensitive
+	// PrefixMatch bool
+	vals map[string]interface{}
+}
+
+// AddVals adds strings and values to an EnumParser.
+func (ep *EnumParser) AddVals(vals map[string]interface{}) {
+	if ep.vals == nil {
+		ep.vals = make(map[string]interface{})
+	}
+	for k, v := range vals {
+		if ep.Type == "" {
+			ep.Type = reflect.TypeOf(v).Name()
+		}
+		if !ep.CaseMatch {
+			k = strings.ToLower(k)
+		}
+		ep.vals[k] = v
+	}
+}
+
+// Parse parses the string and returns the value or an error.
+func (ep EnumParser) Parse(s string) (interface{}, error) {
+	if !ep.CaseMatch {
+		s = strings.ToLower(s)
+	}
+	v, ok := ep.vals[s]
+	if !ok {
+		return false, fmt.Errorf("failed to parse %s %#q", ep.Type, s)
+	}
+	return v, nil
+}

vendor/github.com/go-git/gcfg/types/int.go

@@ -0,0 +1,86 @@
+package types
+
+import (
+	"fmt"
+	"strings"
+)
+
+// An IntMode is a mode for parsing integer values, representing a set of
+// accepted bases.
+type IntMode uint8
+
+// IntMode values for ParseInt; can be combined using binary or.
+const (
+	Dec IntMode = 1 << iota
+	Hex
+	Oct
+)
+
+// String returns a string representation of IntMode; e.g. `IntMode(Dec|Hex)`.
+func (m IntMode) String() string {
+	var modes []string
+	if m&Dec != 0 {
+		modes = append(modes, "Dec")
+	}
+	if m&Hex != 0 {
+		modes = append(modes, "Hex")
+	}
+	if m&Oct != 0 {
+		modes = append(modes, "Oct")
+	}
+	return "IntMode(" + strings.Join(modes, "|") + ")"
+}
+
+var errIntAmbig = fmt.Errorf("ambiguous integer value; must include '0' prefix")
+
+func prefix0(val string) bool {
+	return strings.HasPrefix(val, "0") || strings.HasPrefix(val, "-0")
+}
+
+func prefix0x(val string) bool {
+	return strings.HasPrefix(val, "0x") || strings.HasPrefix(val, "-0x")
+}
+
+// ParseInt parses val using mode into intptr, which must be a pointer to an
+// integer kind type. Non-decimal value require prefix `0` or `0x` in the cases
+// when mode permits ambiguity of base; otherwise the prefix can be omitted.
+func ParseInt(intptr interface{}, val string, mode IntMode) error {
+	val = strings.TrimSpace(val)
+	verb := byte(0)
+	switch mode {
+	case Dec:
+		verb = 'd'
+	case Dec + Hex:
+		if prefix0x(val) {
+			verb = 'v'
+		} else {
+			verb = 'd'
+		}
+	case Dec + Oct:
+		if prefix0(val) && !prefix0x(val) {
+			verb = 'v'
+		} else {
+			verb = 'd'
+		}
+	case Dec + Hex + Oct:
+		verb = 'v'
+	case Hex:
+		if prefix0x(val) {
+			verb = 'v'
+		} else {
+			verb = 'x'
+		}
+	case Oct:
+		verb = 'o'
+	case Hex + Oct:
+		if prefix0(val) {
+			verb = 'v'
+		} else {
+			return errIntAmbig
+		}
+	}
+	if verb == 0 {
+		panic("unsupported mode")
+	}
+	return ScanFully(intptr, val, verb)
+}

vendor/github.com/go-git/gcfg/types/scan.go

@@ -0,0 +1,23 @@
+package types
+
+import (
+	"fmt"
+	"io"
+	"reflect"
+)
+
+// ScanFully uses fmt.Sscanf with verb to fully scan val into ptr.
+func ScanFully(ptr interface{}, val string, verb byte) error {
+	t := reflect.ValueOf(ptr).Elem().Type()
+	// attempt to read extra bytes to make sure the value is consumed
+	var b []byte
+	n, err := fmt.Sscanf(val, "%"+string(verb)+"%s", ptr, &b)
+	switch {
+	case n < 1 || n == 1 && err != io.EOF:
+		return fmt.Errorf("failed to parse %q as %v: %v", val, t, err)
+	case n > 1:
+		return fmt.Errorf("failed to parse %q as %v: extra characters %q", val, t, string(b))
+	}
+	// n == 1 && err == io.EOF
+	return nil
+}

vendor/github.com/go-git/go-billy/v5/.gitignore

@@ -0,0 +1,4 @@
+/coverage.txt
+/vendor
+Gopkg.lock
+Gopkg.toml

vendor/github.com/go-git/go-billy/v5/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+
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+          that such additional attribution notices cannot be construed
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+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
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+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
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+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
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+      has been advised of the possibility of such damages.
+
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+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "{}"
+      replaced with your own identifying information. (Don't include
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+      file or class name and description of purpose be included on the
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+
+   Copyright 2017 Sourced Technologies S.L.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/go-git/go-billy/v5/Makefile

@@ -0,0 +1,11 @@
+# Go parameters
+GOCMD = go
+GOTEST = $(GOCMD) test 
+
+.PHONY: test
+test:
+	$(GOTEST) -race ./...
+
+test-coverage:
+	echo "" > $(COVERAGE_REPORT); \
+	$(GOTEST) -coverprofile=$(COVERAGE_REPORT) -coverpkg=./... -covermode=$(COVERAGE_MODE) ./...

vendor/github.com/go-git/go-billy/v5/README.md

@@ -0,0 +1,73 @@
+# go-billy [![GoDoc](https://godoc.org/gopkg.in/go-git/go-billy.v5?status.svg)](https://pkg.go.dev/github.com/go-git/go-billy/v5) [![Test](https://github.com/go-git/go-billy/workflows/Test/badge.svg)](https://github.com/go-git/go-billy/actions?query=workflow%3ATest)
+
+The missing interface filesystem abstraction for Go.
+Billy implements an interface based on the `os` standard library, allowing to develop applications without dependency on the underlying storage. Makes it virtually free to implement mocks and testing over filesystem operations.
+
+Billy was born as part of [go-git/go-git](https://github.com/go-git/go-git) project.
+
+## Installation
+
+```go
+import "github.com/go-git/go-billy/v5" // with go modules enabled (GO111MODULE=on or outside GOPATH)
+import "github.com/go-git/go-billy" // with go modules disabled
+```
+
+## Usage
+
+Billy exposes filesystems using the
+[`Filesystem` interface](https://pkg.go.dev/github.com/go-git/go-billy/v5?tab=doc#Filesystem).
+Each filesystem implementation gives you a `New` method, whose arguments depend on
+the implementation itself, that returns a new `Filesystem`.
+
+The following example caches in memory all readable files in a directory from any
+billy's filesystem implementation.
+
+```go
+func LoadToMemory(origin billy.Filesystem, path string) (*memory.Memory, error) {
+	memory := memory.New()
+
+	files, err := origin.ReadDir("/")
+	if err != nil {
+		return nil, err
+	}
+
+	for _, file := range files {
+		if file.IsDir() {
+			continue
+		}
+
+		src, err := origin.Open(file.Name())
+		if err != nil {
+			return nil, err
+		}
+
+		dst, err := memory.Create(file.Name())
+		if err != nil {
+			return nil, err
+		}
+
+		if _, err = io.Copy(dst, src); err != nil {
+			return nil, err
+		}
+
+		if err := dst.Close(); err != nil {
+			return nil, err
+		}
+
+		if err := src.Close(); err != nil {
+			return nil, err
+		}
+	}
+
+	return memory, nil
+}
+```
+
+## Why billy?
+
+The library billy deals with storage systems and Billy is the name of a well-known, IKEA
+bookcase. That's it.
+
+## License
+
+Apache License Version 2.0, see [LICENSE](LICENSE)

vendor/github.com/go-git/go-billy/v5/fs.go

@@ -0,0 +1,202 @@
+package billy
+
+import (
+	"errors"
+	"io"
+	"os"
+	"time"
+)
+
+var (
+	ErrReadOnly        = errors.New("read-only filesystem")
+	ErrNotSupported    = errors.New("feature not supported")
+	ErrCrossedBoundary = errors.New("chroot boundary crossed")
+)
+
+// Capability holds the supported features of a billy filesystem. This does
+// not mean that the capability has to be supported by the underlying storage.
+// For example, a billy filesystem may support WriteCapability but the
+// storage be mounted in read only mode.
+type Capability uint64
+
+const (
+	// WriteCapability means that the fs is writable.
+	WriteCapability Capability = 1 << iota
+	// ReadCapability means that the fs is readable.
+	ReadCapability
+	// ReadAndWriteCapability is the ability to open a file in read and write mode.
+	ReadAndWriteCapability
+	// SeekCapability means it is able to move position inside the file.
+	SeekCapability
+	// TruncateCapability means that a file can be truncated.
+	TruncateCapability
+	// LockCapability is the ability to lock a file.
+	LockCapability
+
+	// DefaultCapabilities lists all capable features supported by filesystems
+	// without Capability interface. This list should not be changed until a
+	// major version is released.
+	DefaultCapabilities Capability = WriteCapability | ReadCapability |
+		ReadAndWriteCapability | SeekCapability | TruncateCapability |
+		LockCapability
+
+	// AllCapabilities lists all capable features.
+	AllCapabilities Capability = WriteCapability | ReadCapability |
+		ReadAndWriteCapability | SeekCapability | TruncateCapability |
+		LockCapability
+)
+
+// Filesystem abstract the operations in a storage-agnostic interface.
+// Each method implementation mimics the behavior of the equivalent functions
+// at the os package from the standard library.
+type Filesystem interface {
+	Basic
+	TempFile
+	Dir
+	Symlink
+	Chroot
+}
+
+// Basic abstract the basic operations in a storage-agnostic interface as
+// an extension to the Basic interface.
+type Basic interface {
+	// Create creates the named file with mode 0666 (before umask), truncating
+	// it if it already exists. If successful, methods on the returned File can
+	// be used for I/O; the associated file descriptor has mode O_RDWR.
+	Create(filename string) (File, error)
+	// Open opens the named file for reading. If successful, methods on the
+	// returned file can be used for reading; the associated file descriptor has
+	// mode O_RDONLY.
+	Open(filename string) (File, error)
+	// OpenFile is the generalized open call; most users will use Open or Create
+	// instead. It opens the named file with specified flag (O_RDONLY etc.) and
+	// perm, (0666 etc.) if applicable. If successful, methods on the returned
+	// File can be used for I/O.
+	OpenFile(filename string, flag int, perm os.FileMode) (File, error)
+	// Stat returns a FileInfo describing the named file.
+	Stat(filename string) (os.FileInfo, error)
+	// Rename renames (moves) oldpath to newpath. If newpath already exists and
+	// is not a directory, Rename replaces it. OS-specific restrictions may
+	// apply when oldpath and newpath are in different directories.
+	Rename(oldpath, newpath string) error
+	// Remove removes the named file or directory.
+	Remove(filename string) error
+	// Join joins any number of path elements into a single path, adding a
+	// Separator if necessary. Join calls filepath.Clean on the result; in
+	// particular, all empty strings are ignored. On Windows, the result is a
+	// UNC path if and only if the first path element is a UNC path.
+	Join(elem ...string) string
+}
+
+type TempFile interface {
+	// TempFile creates a new temporary file in the directory dir with a name
+	// beginning with prefix, opens the file for reading and writing, and
+	// returns the resulting *os.File. If dir is the empty string, TempFile
+	// uses the default directory for temporary files (see os.TempDir).
+	// Multiple programs calling TempFile simultaneously will not choose the
+	// same file. The caller can use f.Name() to find the pathname of the file.
+	// It is the caller's responsibility to remove the file when no longer
+	// needed.
+	TempFile(dir, prefix string) (File, error)
+}
+
+// Dir abstract the dir related operations in a storage-agnostic interface as
+// an extension to the Basic interface.
+type Dir interface {
+	// ReadDir reads the directory named by dirname and returns a list of
+	// directory entries sorted by filename.
+	ReadDir(path string) ([]os.FileInfo, error)
+	// MkdirAll creates a directory named path, along with any necessary
+	// parents, and returns nil, or else returns an error. The permission bits
+	// perm are used for all directories that MkdirAll creates. If path is/
+	// already a directory, MkdirAll does nothing and returns nil.
+	MkdirAll(filename string, perm os.FileMode) error
+}
+
+// Symlink abstract the symlink related operations in a storage-agnostic
+// interface as an extension to the Basic interface.
+type Symlink interface {
+	// Lstat returns a FileInfo describing the named file. If the file is a
+	// symbolic link, the returned FileInfo describes the symbolic link. Lstat
+	// makes no attempt to follow the link.
+	Lstat(filename string) (os.FileInfo, error)
+	// Symlink creates a symbolic-link from link to target. target may be an
+	// absolute or relative path, and need not refer to an existing node.
+	// Parent directories of link are created as necessary.
+	Symlink(target, link string) error
+	// Readlink returns the target path of link.
+	Readlink(link string) (string, error)
+}
+
+// Change abstract the FileInfo change related operations in a storage-agnostic
+// interface as an extension to the Basic interface
+type Change interface {
+	// Chmod changes the mode of the named file to mode. If the file is a
+	// symbolic link, it changes the mode of the link's target.
+	Chmod(name string, mode os.FileMode) error
+	// Lchown changes the numeric uid and gid of the named file. If the file is
+	// a symbolic link, it changes the uid and gid of the link itself.
+	Lchown(name string, uid, gid int) error
+	// Chown changes the numeric uid and gid of the named file. If the file is a
+	// symbolic link, it changes the uid and gid of the link's target.
+	Chown(name string, uid, gid int) error
+	// Chtimes changes the access and modification times of the named file,
+	// similar to the Unix utime() or utimes() functions.
+	//
+	// The underlying filesystem may truncate or round the values to a less
+	// precise time unit.
+	Chtimes(name string, atime time.Time, mtime time.Time) error
+}
+
+// Chroot abstract the chroot related operations in a storage-agnostic interface
+// as an extension to the Basic interface.
+type Chroot interface {
+	// Chroot returns a new filesystem from the same type where the new root is
+	// the given path. Files outside of the designated directory tree cannot be
+	// accessed.
+	Chroot(path string) (Filesystem, error)
+	// Root returns the root path of the filesystem.
+	Root() string
+}
+
+// File represent a file, being a subset of the os.File
+type File interface {
+	// Name returns the name of the file as presented to Open.
+	Name() string
+	io.Writer
+	io.Reader
+	io.ReaderAt
+	io.Seeker
+	io.Closer
+	// Lock locks the file like e.g. flock. It protects against access from
+	// other processes.
+	Lock() error
+	// Unlock unlocks the file.
+	Unlock() error
+	// Truncate the file.
+	Truncate(size int64) error
+}
+
+// Capable interface can return the available features of a filesystem.
+type Capable interface {
+	// Capabilities returns the capabilities of a filesystem in bit flags.
+	Capabilities() Capability
+}
+
+// Capabilities returns the features supported by a filesystem. If the FS
+// does not implement Capable interface it returns all features.
+func Capabilities(fs Basic) Capability {
+	capable, ok := fs.(Capable)
+	if !ok {
+		return DefaultCapabilities
+	}
+
+	return capable.Capabilities()
+}
+
+// CapabilityCheck tests the filesystem for the provided capabilities and
+// returns true in case it supports all of them.
+func CapabilityCheck(fs Basic, capabilities Capability) bool {
+	fsCaps := Capabilities(fs)
+	return fsCaps&capabilities == capabilities
+}

vendor/github.com/go-git/go-billy/v5/helper/chroot/chroot.go

@@ -0,0 +1,242 @@
+package chroot
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/go-git/go-billy/v5"
+	"github.com/go-git/go-billy/v5/helper/polyfill"
+)
+
+// ChrootHelper is a helper to implement billy.Chroot.
+type ChrootHelper struct {
+	underlying billy.Filesystem
+	base       string
+}
+
+// New creates a new filesystem wrapping up the given 'fs'.
+// The created filesystem has its base in the given ChrootHelperectory of the
+// underlying filesystem.
+func New(fs billy.Basic, base string) billy.Filesystem {
+	return &ChrootHelper{
+		underlying: polyfill.New(fs),
+		base:       base,
+	}
+}
+
+func (fs *ChrootHelper) underlyingPath(filename string) (string, error) {
+	if isCrossBoundaries(filename) {
+		return "", billy.ErrCrossedBoundary
+	}
+
+	return fs.Join(fs.Root(), filename), nil
+}
+
+func isCrossBoundaries(path string) bool {
+	path = filepath.ToSlash(path)
+	path = filepath.Clean(path)
+
+	return strings.HasPrefix(path, ".."+string(filepath.Separator))
+}
+
+func (fs *ChrootHelper) Create(filename string) (billy.File, error) {
+	fullpath, err := fs.underlyingPath(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	f, err := fs.underlying.Create(fullpath)
+	if err != nil {
+		return nil, err
+	}
+
+	return newFile(fs, f, filename), nil
+}
+
+func (fs *ChrootHelper) Open(filename string) (billy.File, error) {
+	fullpath, err := fs.underlyingPath(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	f, err := fs.underlying.Open(fullpath)
+	if err != nil {
+		return nil, err
+	}
+
+	return newFile(fs, f, filename), nil
+}
+
+func (fs *ChrootHelper) OpenFile(filename string, flag int, mode os.FileMode) (billy.File, error) {
+	fullpath, err := fs.underlyingPath(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	f, err := fs.underlying.OpenFile(fullpath, flag, mode)
+	if err != nil {
+		return nil, err
+	}
+
+	return newFile(fs, f, filename), nil
+}
+
+func (fs *ChrootHelper) Stat(filename string) (os.FileInfo, error) {
+	fullpath, err := fs.underlyingPath(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.underlying.Stat(fullpath)
+}
+
+func (fs *ChrootHelper) Rename(from, to string) error {
+	var err error
+	from, err = fs.underlyingPath(from)
+	if err != nil {
+		return err
+	}
+
+	to, err = fs.underlyingPath(to)
+	if err != nil {
+		return err
+	}
+
+	return fs.underlying.Rename(from, to)
+}
+
+func (fs *ChrootHelper) Remove(path string) error {
+	fullpath, err := fs.underlyingPath(path)
+	if err != nil {
+		return err
+	}
+
+	return fs.underlying.Remove(fullpath)
+}
+
+func (fs *ChrootHelper) Join(elem ...string) string {
+	return fs.underlying.Join(elem...)
+}
+
+func (fs *ChrootHelper) TempFile(dir, prefix string) (billy.File, error) {
+	fullpath, err := fs.underlyingPath(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	f, err := fs.underlying.(billy.TempFile).TempFile(fullpath, prefix)
+	if err != nil {
+		return nil, err
+	}
+
+	return newFile(fs, f, fs.Join(dir, filepath.Base(f.Name()))), nil
+}
+
+func (fs *ChrootHelper) ReadDir(path string) ([]os.FileInfo, error) {
+	fullpath, err := fs.underlyingPath(path)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.underlying.(billy.Dir).ReadDir(fullpath)
+}
+
+func (fs *ChrootHelper) MkdirAll(filename string, perm os.FileMode) error {
+	fullpath, err := fs.underlyingPath(filename)
+	if err != nil {
+		return err
+	}
+
+	return fs.underlying.(billy.Dir).MkdirAll(fullpath, perm)
+}
+
+func (fs *ChrootHelper) Lstat(filename string) (os.FileInfo, error) {
+	fullpath, err := fs.underlyingPath(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.underlying.(billy.Symlink).Lstat(fullpath)
+}
+
+func (fs *ChrootHelper) Symlink(target, link string) error {
+	target = filepath.FromSlash(target)
+
+	// only rewrite target if it's already absolute
+	if filepath.IsAbs(target) || strings.HasPrefix(target, string(filepath.Separator)) {
+		target = fs.Join(fs.Root(), target)
+		target = filepath.Clean(filepath.FromSlash(target))
+	}
+
+	link, err := fs.underlyingPath(link)
+	if err != nil {
+		return err
+	}
+
+	return fs.underlying.(billy.Symlink).Symlink(target, link)
+}
+
+func (fs *ChrootHelper) Readlink(link string) (string, error) {
+	fullpath, err := fs.underlyingPath(link)
+	if err != nil {
+		return "", err
+	}
+
+	target, err := fs.underlying.(billy.Symlink).Readlink(fullpath)
+	if err != nil {
+		return "", err
+	}
+
+	if !filepath.IsAbs(target) && !strings.HasPrefix(target, string(filepath.Separator)) {
+		return target, nil
+	}
+
+	target, err = filepath.Rel(fs.base, target)
+	if err != nil {
+		return "", err
+	}
+
+	return string(os.PathSeparator) + target, nil
+}
+
+func (fs *ChrootHelper) Chroot(path string) (billy.Filesystem, error) {
+	fullpath, err := fs.underlyingPath(path)
+	if err != nil {
+		return nil, err
+	}
+
+	return New(fs.underlying, fullpath), nil
+}
+
+func (fs *ChrootHelper) Root() string {
+	return fs.base
+}
+
+func (fs *ChrootHelper) Underlying() billy.Basic {
+	return fs.underlying
+}
+
+// Capabilities implements the Capable interface.
+func (fs *ChrootHelper) Capabilities() billy.Capability {
+	return billy.Capabilities(fs.underlying)
+}
+
+type file struct {
+	billy.File
+	name string
+}
+
+func newFile(fs billy.Filesystem, f billy.File, filename string) billy.File {
+	filename = fs.Join(fs.Root(), filename)
+	filename, _ = filepath.Rel(fs.Root(), filename)
+
+	return &file{
+		File: f,
+		name: filename,
+	}
+}
+
+func (f *file) Name() string {
+	return f.name
+}

vendor/github.com/go-git/go-billy/v5/helper/polyfill/polyfill.go

@@ -0,0 +1,105 @@
+package polyfill
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/go-git/go-billy/v5"
+)
+
+// Polyfill is a helper that implements all missing method from billy.Filesystem.
+type Polyfill struct {
+	billy.Basic
+	c capabilities
+}
+
+type capabilities struct{ tempfile, dir, symlink, chroot bool }
+
+// New creates a new filesystem wrapping up 'fs' the intercepts all the calls
+// made and errors if fs doesn't implement any of the billy interfaces.
+func New(fs billy.Basic) billy.Filesystem {
+	if original, ok := fs.(billy.Filesystem); ok {
+		return original
+	}
+
+	h := &Polyfill{Basic: fs}
+
+	_, h.c.tempfile = h.Basic.(billy.TempFile)
+	_, h.c.dir = h.Basic.(billy.Dir)
+	_, h.c.symlink = h.Basic.(billy.Symlink)
+	_, h.c.chroot = h.Basic.(billy.Chroot)
+	return h
+}
+
+func (h *Polyfill) TempFile(dir, prefix string) (billy.File, error) {
+	if !h.c.tempfile {
+		return nil, billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.TempFile).TempFile(dir, prefix)
+}
+
+func (h *Polyfill) ReadDir(path string) ([]os.FileInfo, error) {
+	if !h.c.dir {
+		return nil, billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.Dir).ReadDir(path)
+}
+
+func (h *Polyfill) MkdirAll(filename string, perm os.FileMode) error {
+	if !h.c.dir {
+		return billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.Dir).MkdirAll(filename, perm)
+}
+
+func (h *Polyfill) Symlink(target, link string) error {
+	if !h.c.symlink {
+		return billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.Symlink).Symlink(target, link)
+}
+
+func (h *Polyfill) Readlink(link string) (string, error) {
+	if !h.c.symlink {
+		return "", billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.Symlink).Readlink(link)
+}
+
+func (h *Polyfill) Lstat(path string) (os.FileInfo, error) {
+	if !h.c.symlink {
+		return nil, billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.Symlink).Lstat(path)
+}
+
+func (h *Polyfill) Chroot(path string) (billy.Filesystem, error) {
+	if !h.c.chroot {
+		return nil, billy.ErrNotSupported
+	}
+
+	return h.Basic.(billy.Chroot).Chroot(path)
+}
+
+func (h *Polyfill) Root() string {
+	if !h.c.chroot {
+		return string(filepath.Separator)
+	}
+
+	return h.Basic.(billy.Chroot).Root()
+}
+
+func (h *Polyfill) Underlying() billy.Basic {
+	return h.Basic
+}
+
+// Capabilities implements the Capable interface.
+func (h *Polyfill) Capabilities() billy.Capability {
+	return billy.Capabilities(h.Basic)
+}

vendor/github.com/go-git/go-billy/v5/memfs/memory.go

@@ -0,0 +1,410 @@
+// Package memfs provides a billy filesystem base on memory.
+package memfs // import "github.com/go-git/go-billy/v5/memfs"
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/go-git/go-billy/v5"
+	"github.com/go-git/go-billy/v5/helper/chroot"
+	"github.com/go-git/go-billy/v5/util"
+)
+
+const separator = filepath.Separator
+
+// Memory a very convenient filesystem based on memory files
+type Memory struct {
+	s *storage
+
+	tempCount int
+}
+
+// New returns a new Memory filesystem.
+func New() billy.Filesystem {
+	fs := &Memory{s: newStorage()}
+	return chroot.New(fs, string(separator))
+}
+
+func (fs *Memory) Create(filename string) (billy.File, error) {
+	return fs.OpenFile(filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+}
+
+func (fs *Memory) Open(filename string) (billy.File, error) {
+	return fs.OpenFile(filename, os.O_RDONLY, 0)
+}
+
+func (fs *Memory) OpenFile(filename string, flag int, perm os.FileMode) (billy.File, error) {
+	f, has := fs.s.Get(filename)
+	if !has {
+		if !isCreate(flag) {
+			return nil, os.ErrNotExist
+		}
+
+		var err error
+		f, err = fs.s.New(filename, perm, flag)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		if isExclusive(flag) {
+			return nil, os.ErrExist
+		}
+
+		if target, isLink := fs.resolveLink(filename, f); isLink {
+			return fs.OpenFile(target, flag, perm)
+		}
+	}
+
+	if f.mode.IsDir() {
+		return nil, fmt.Errorf("cannot open directory: %s", filename)
+	}
+
+	return f.Duplicate(filename, perm, flag), nil
+}
+
+var errNotLink = errors.New("not a link")
+
+func (fs *Memory) resolveLink(fullpath string, f *file) (target string, isLink bool) {
+	if !isSymlink(f.mode) {
+		return fullpath, false
+	}
+
+	target = string(f.content.bytes)
+	if !isAbs(target) {
+		target = fs.Join(filepath.Dir(fullpath), target)
+	}
+
+	return target, true
+}
+
+// On Windows OS, IsAbs validates if a path is valid based on if stars with a
+// unit (eg.: `C:\`)  to assert that is absolute, but in this mem implementation
+// any path starting by `separator` is also considered absolute.
+func isAbs(path string) bool {
+	return filepath.IsAbs(path) || strings.HasPrefix(path, string(separator))
+}
+
+func (fs *Memory) Stat(filename string) (os.FileInfo, error) {
+	f, has := fs.s.Get(filename)
+	if !has {
+		return nil, os.ErrNotExist
+	}
+
+	fi, _ := f.Stat()
+
+	var err error
+	if target, isLink := fs.resolveLink(filename, f); isLink {
+		fi, err = fs.Stat(target)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// the name of the file should always the name of the stated file, so we
+	// overwrite the Stat returned from the storage with it, since the
+	// filename may belong to a link.
+	fi.(*fileInfo).name = filepath.Base(filename)
+	return fi, nil
+}
+
+func (fs *Memory) Lstat(filename string) (os.FileInfo, error) {
+	f, has := fs.s.Get(filename)
+	if !has {
+		return nil, os.ErrNotExist
+	}
+
+	return f.Stat()
+}
+
+type ByName []os.FileInfo
+
+func (a ByName) Len() int           { return len(a) }
+func (a ByName) Less(i, j int) bool { return a[i].Name() < a[j].Name() }
+func (a ByName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+func (fs *Memory) ReadDir(path string) ([]os.FileInfo, error) {
+	if f, has := fs.s.Get(path); has {
+		if target, isLink := fs.resolveLink(path, f); isLink {
+			return fs.ReadDir(target)
+		}
+	}
+
+	var entries []os.FileInfo
+	for _, f := range fs.s.Children(path) {
+		fi, _ := f.Stat()
+		entries = append(entries, fi)
+	}
+
+	sort.Sort(ByName(entries))
+
+	return entries, nil
+}
+
+func (fs *Memory) MkdirAll(path string, perm os.FileMode) error {
+	_, err := fs.s.New(path, perm|os.ModeDir, 0)
+	return err
+}
+
+func (fs *Memory) TempFile(dir, prefix string) (billy.File, error) {
+	return util.TempFile(fs, dir, prefix)
+}
+
+func (fs *Memory) getTempFilename(dir, prefix string) string {
+	fs.tempCount++
+	filename := fmt.Sprintf("%s_%d_%d", prefix, fs.tempCount, time.Now().UnixNano())
+	return fs.Join(dir, filename)
+}
+
+func (fs *Memory) Rename(from, to string) error {
+	return fs.s.Rename(from, to)
+}
+
+func (fs *Memory) Remove(filename string) error {
+	return fs.s.Remove(filename)
+}
+
+func (fs *Memory) Join(elem ...string) string {
+	return filepath.Join(elem...)
+}
+
+func (fs *Memory) Symlink(target, link string) error {
+	_, err := fs.Stat(link)
+	if err == nil {
+		return os.ErrExist
+	}
+
+	if !os.IsNotExist(err) {
+		return err
+	}
+
+	return util.WriteFile(fs, link, []byte(target), 0777|os.ModeSymlink)
+}
+
+func (fs *Memory) Readlink(link string) (string, error) {
+	f, has := fs.s.Get(link)
+	if !has {
+		return "", os.ErrNotExist
+	}
+
+	if !isSymlink(f.mode) {
+		return "", &os.PathError{
+			Op:   "readlink",
+			Path: link,
+			Err:  fmt.Errorf("not a symlink"),
+		}
+	}
+
+	return string(f.content.bytes), nil
+}
+
+// Capabilities implements the Capable interface.
+func (fs *Memory) Capabilities() billy.Capability {
+	return billy.WriteCapability |
+		billy.ReadCapability |
+		billy.ReadAndWriteCapability |
+		billy.SeekCapability |
+		billy.TruncateCapability
+}
+
+type file struct {
+	name     string
+	content  *content
+	position int64
+	flag     int
+	mode     os.FileMode
+
+	isClosed bool
+}
+
+func (f *file) Name() string {
+	return f.name
+}
+
+func (f *file) Read(b []byte) (int, error) {
+	n, err := f.ReadAt(b, f.position)
+	f.position += int64(n)
+
+	if err == io.EOF && n != 0 {
+		err = nil
+	}
+
+	return n, err
+}
+
+func (f *file) ReadAt(b []byte, off int64) (int, error) {
+	if f.isClosed {
+		return 0, os.ErrClosed
+	}
+
+	if !isReadAndWrite(f.flag) && !isReadOnly(f.flag) {
+		return 0, errors.New("read not supported")
+	}
+
+	n, err := f.content.ReadAt(b, off)
+
+	return n, err
+}
+
+func (f *file) Seek(offset int64, whence int) (int64, error) {
+	if f.isClosed {
+		return 0, os.ErrClosed
+	}
+
+	switch whence {
+	case io.SeekCurrent:
+		f.position += offset
+	case io.SeekStart:
+		f.position = offset
+	case io.SeekEnd:
+		f.position = int64(f.content.Len()) + offset
+	}
+
+	return f.position, nil
+}
+
+func (f *file) Write(p []byte) (int, error) {
+	if f.isClosed {
+		return 0, os.ErrClosed
+	}
+
+	if !isReadAndWrite(f.flag) && !isWriteOnly(f.flag) {
+		return 0, errors.New("write not supported")
+	}
+
+	n, err := f.content.WriteAt(p, f.position)
+	f.position += int64(n)
+
+	return n, err
+}
+
+func (f *file) Close() error {
+	if f.isClosed {
+		return os.ErrClosed
+	}
+
+	f.isClosed = true
+	return nil
+}
+
+func (f *file) Truncate(size int64) error {
+	if size < int64(len(f.content.bytes)) {
+		f.content.bytes = f.content.bytes[:size]
+	} else if more := int(size) - len(f.content.bytes); more > 0 {
+		f.content.bytes = append(f.content.bytes, make([]byte, more)...)
+	}
+
+	return nil
+}
+
+func (f *file) Duplicate(filename string, mode os.FileMode, flag int) billy.File {
+	new := &file{
+		name:    filename,
+		content: f.content,
+		mode:    mode,
+		flag:    flag,
+	}
+
+	if isTruncate(flag) {
+		new.content.Truncate()
+	}
+
+	if isAppend(flag) {
+		new.position = int64(new.content.Len())
+	}
+
+	return new
+}
+
+func (f *file) Stat() (os.FileInfo, error) {
+	return &fileInfo{
+		name: f.Name(),
+		mode: f.mode,
+		size: f.content.Len(),
+	}, nil
+}
+
+// Lock is a no-op in memfs.
+func (f *file) Lock() error {
+	return nil
+}
+
+// Unlock is a no-op in memfs.
+func (f *file) Unlock() error {
+	return nil
+}
+
+type fileInfo struct {
+	name string
+	size int
+	mode os.FileMode
+}
+
+func (fi *fileInfo) Name() string {
+	return fi.name
+}
+
+func (fi *fileInfo) Size() int64 {
+	return int64(fi.size)
+}
+
+func (fi *fileInfo) Mode() os.FileMode {
+	return fi.mode
+}
+
+func (*fileInfo) ModTime() time.Time {
+	return time.Now()
+}
+
+func (fi *fileInfo) IsDir() bool {
+	return fi.mode.IsDir()
+}
+
+func (*fileInfo) Sys() interface{} {
+	return nil
+}
+
+func (c *content) Truncate() {
+	c.bytes = make([]byte, 0)
+}
+
+func (c *content) Len() int {
+	return len(c.bytes)
+}
+
+func isCreate(flag int) bool {
+	return flag&os.O_CREATE != 0
+}
+
+func isExclusive(flag int) bool {
+	return flag&os.O_EXCL != 0
+}
+
+func isAppend(flag int) bool {
+	return flag&os.O_APPEND != 0
+}
+
+func isTruncate(flag int) bool {
+	return flag&os.O_TRUNC != 0
+}
+
+func isReadAndWrite(flag int) bool {
+	return flag&os.O_RDWR != 0
+}
+
+func isReadOnly(flag int) bool {
+	return flag == os.O_RDONLY
+}
+
+func isWriteOnly(flag int) bool {
+	return flag&os.O_WRONLY != 0
+}
+
+func isSymlink(m os.FileMode) bool {
+	return m&os.ModeSymlink != 0
+}

vendor/github.com/go-git/go-billy/v5/memfs/storage.go

@@ -0,0 +1,238 @@
+package memfs
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sync"
+)
+
+type storage struct {
+	files    map[string]*file
+	children map[string]map[string]*file
+}
+
+func newStorage() *storage {
+	return &storage{
+		files:    make(map[string]*file, 0),
+		children: make(map[string]map[string]*file, 0),
+	}
+}
+
+func (s *storage) Has(path string) bool {
+	path = clean(path)
+
+	_, ok := s.files[path]
+	return ok
+}
+
+func (s *storage) New(path string, mode os.FileMode, flag int) (*file, error) {
+	path = clean(path)
+	if s.Has(path) {
+		if !s.MustGet(path).mode.IsDir() {
+			return nil, fmt.Errorf("file already exists %q", path)
+		}
+
+		return nil, nil
+	}
+
+	name := filepath.Base(path)
+
+	f := &file{
+		name:    name,
+		content: &content{name: name},
+		mode:    mode,
+		flag:    flag,
+	}
+
+	s.files[path] = f
+	s.createParent(path, mode, f)
+	return f, nil
+}
+
+func (s *storage) createParent(path string, mode os.FileMode, f *file) error {
+	base := filepath.Dir(path)
+	base = clean(base)
+	if f.Name() == string(separator) {
+		return nil
+	}
+
+	if _, err := s.New(base, mode.Perm()|os.ModeDir, 0); err != nil {
+		return err
+	}
+
+	if _, ok := s.children[base]; !ok {
+		s.children[base] = make(map[string]*file, 0)
+	}
+
+	s.children[base][f.Name()] = f
+	return nil
+}
+
+func (s *storage) Children(path string) []*file {
+	path = clean(path)
+
+	l := make([]*file, 0)
+	for _, f := range s.children[path] {
+		l = append(l, f)
+	}
+
+	return l
+}
+
+func (s *storage) MustGet(path string) *file {
+	f, ok := s.Get(path)
+	if !ok {
+		panic(fmt.Errorf("couldn't find %q", path))
+	}
+
+	return f
+}
+
+func (s *storage) Get(path string) (*file, bool) {
+	path = clean(path)
+	if !s.Has(path) {
+		return nil, false
+	}
+
+	file, ok := s.files[path]
+	return file, ok
+}
+
+func (s *storage) Rename(from, to string) error {
+	from = clean(from)
+	to = clean(to)
+
+	if !s.Has(from) {
+		return os.ErrNotExist
+	}
+
+	move := [][2]string{{from, to}}
+
+	for pathFrom := range s.files {
+		if pathFrom == from || !filepath.HasPrefix(pathFrom, from) {
+			continue
+		}
+
+		rel, _ := filepath.Rel(from, pathFrom)
+		pathTo := filepath.Join(to, rel)
+
+		move = append(move, [2]string{pathFrom, pathTo})
+	}
+
+	for _, ops := range move {
+		from := ops[0]
+		to := ops[1]
+
+		if err := s.move(from, to); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (s *storage) move(from, to string) error {
+	s.files[to] = s.files[from]
+	s.files[to].name = filepath.Base(to)
+	s.children[to] = s.children[from]
+
+	defer func() {
+		delete(s.children, from)
+		delete(s.files, from)
+		delete(s.children[filepath.Dir(from)], filepath.Base(from))
+	}()
+
+	return s.createParent(to, 0644, s.files[to])
+}
+
+func (s *storage) Remove(path string) error {
+	path = clean(path)
+
+	f, has := s.Get(path)
+	if !has {
+		return os.ErrNotExist
+	}
+
+	if f.mode.IsDir() && len(s.children[path]) != 0 {
+		return fmt.Errorf("dir: %s contains files", path)
+	}
+
+	base, file := filepath.Split(path)
+	base = filepath.Clean(base)
+
+	delete(s.children[base], file)
+	delete(s.files, path)
+	return nil
+}
+
+func clean(path string) string {
+	return filepath.Clean(filepath.FromSlash(path))
+}
+
+type content struct {
+	name  string
+	bytes []byte
+
+	m sync.RWMutex
+}
+
+func (c *content) WriteAt(p []byte, off int64) (int, error) {
+	if off < 0 {
+		return 0, &os.PathError{
+			Op:   "writeat",
+			Path: c.name,
+			Err:  errors.New("negative offset"),
+		}
+	}
+
+	c.m.Lock()
+	prev := len(c.bytes)
+
+	diff := int(off) - prev
+	if diff > 0 {
+		c.bytes = append(c.bytes, make([]byte, diff)...)
+	}
+
+	c.bytes = append(c.bytes[:off], p...)
+	if len(c.bytes) < prev {
+		c.bytes = c.bytes[:prev]
+	}
+	c.m.Unlock()
+
+	return len(p), nil
+}
+
+func (c *content) ReadAt(b []byte, off int64) (n int, err error) {
+	if off < 0 {
+		return 0, &os.PathError{
+			Op:   "readat",
+			Path: c.name,
+			Err:  errors.New("negative offset"),
+		}
+	}
+
+	c.m.RLock()
+	size := int64(len(c.bytes))
+	if off >= size {
+		c.m.RUnlock()
+		return 0, io.EOF
+	}
+
+	l := int64(len(b))
+	if off+l > size {
+		l = size - off
+	}
+
+	btr := c.bytes[off : off+l]
+	n = copy(b, btr)
+
+	if len(btr) < len(b) {
+		err = io.EOF
+	}
+	c.m.RUnlock()
+
+	return
+}

vendor/github.com/go-git/go-billy/v5/osfs/os.go

@@ -0,0 +1,127 @@
+//go:build !js
+// +build !js
+
+// Package osfs provides a billy filesystem for the OS.
+package osfs
+
+import (
+	"fmt"
+	"io/fs"
+	"os"
+	"sync"
+
+	"github.com/go-git/go-billy/v5"
+)
+
+const (
+	defaultDirectoryMode = 0o755
+	defaultCreateMode    = 0o666
+)
+
+// Default Filesystem representing the root of the os filesystem.
+var Default = &ChrootOS{}
+
+// New returns a new OS filesystem.
+// By default paths are deduplicated, but still enforced
+// under baseDir. For more info refer to WithDeduplicatePath.
+func New(baseDir string, opts ...Option) billy.Filesystem {
+	o := &options{
+		deduplicatePath: true,
+	}
+	for _, opt := range opts {
+		opt(o)
+	}
+
+	if o.Type == BoundOSFS {
+		return newBoundOS(baseDir, o.deduplicatePath)
+	}
+
+	return newChrootOS(baseDir)
+}
+
+// WithBoundOS returns the option of using a Bound filesystem OS.
+func WithBoundOS() Option {
+	return func(o *options) {
+		o.Type = BoundOSFS
+	}
+}
+
+// WithChrootOS returns the option of using a Chroot filesystem OS.
+func WithChrootOS() Option {
+	return func(o *options) {
+		o.Type = ChrootOSFS
+	}
+}
+
+// WithDeduplicatePath toggles the deduplication of the base dir in the path.
+// This occurs when absolute links are being used.
+// Assuming base dir /base/dir and an absolute symlink /base/dir/target:
+//
+// With DeduplicatePath (default): /base/dir/target
+// Without DeduplicatePath: /base/dir/base/dir/target
+//
+// This option is only used by the BoundOS OS type.
+func WithDeduplicatePath(enabled bool) Option {
+	return func(o *options) {
+		o.deduplicatePath = enabled
+	}
+}
+
+type options struct {
+	Type
+	deduplicatePath bool
+}
+
+type Type int
+
+const (
+	ChrootOSFS Type = iota
+	BoundOSFS
+)
+
+func readDir(dir string) ([]os.FileInfo, error) {
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return nil, err
+	}
+	infos := make([]fs.FileInfo, 0, len(entries))
+	for _, entry := range entries {
+		fi, err := entry.Info()
+		if err != nil {
+			return nil, err
+		}
+		infos = append(infos, fi)
+	}
+	return infos, nil
+}
+
+func tempFile(dir, prefix string) (billy.File, error) {
+	f, err := os.CreateTemp(dir, prefix)
+	if err != nil {
+		return nil, err
+	}
+	return &file{File: f}, nil
+}
+
+func openFile(fn string, flag int, perm os.FileMode, createDir func(string) error) (billy.File, error) {
+	if flag&os.O_CREATE != 0 {
+		if createDir == nil {
+			return nil, fmt.Errorf("createDir func cannot be nil if file needs to be opened in create mode")
+		}
+		if err := createDir(fn); err != nil {
+			return nil, err
+		}
+	}
+
+	f, err := os.OpenFile(fn, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	return &file{File: f}, err
+}
+
+// file is a wrapper for an os.File which adds support for file locking.
+type file struct {
+	*os.File
+	m sync.Mutex
+}

vendor/github.com/go-git/go-billy/v5/osfs/os_bound.go

@@ -0,0 +1,261 @@
+//go:build !js
+// +build !js
+
+/*
+   Copyright 2022 The Flux authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package osfs
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	securejoin "github.com/cyphar/filepath-securejoin"
+	"github.com/go-git/go-billy/v5"
+)
+
+// BoundOS is a fs implementation based on the OS filesystem which is bound to
+// a base dir.
+// Prefer this fs implementation over ChrootOS.
+//
+// Behaviours of note:
+//  1. Read and write operations can only be directed to files which descends
+//     from the base dir.
+//  2. Symlinks don't have their targets modified, and therefore can point
+//     to locations outside the base dir or to non-existent paths.
+//  3. Readlink and Lstat ensures that the link file is located within the base
+//     dir, evaluating any symlinks that file or base dir may contain.
+type BoundOS struct {
+	baseDir         string
+	deduplicatePath bool
+}
+
+func newBoundOS(d string, deduplicatePath bool) billy.Filesystem {
+	return &BoundOS{baseDir: d, deduplicatePath: deduplicatePath}
+}
+
+func (fs *BoundOS) Create(filename string) (billy.File, error) {
+	return fs.OpenFile(filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, defaultCreateMode)
+}
+
+func (fs *BoundOS) OpenFile(filename string, flag int, perm os.FileMode) (billy.File, error) {
+	fn, err := fs.abs(filename)
+	if err != nil {
+		return nil, err
+	}
+	return openFile(fn, flag, perm, fs.createDir)
+}
+
+func (fs *BoundOS) ReadDir(path string) ([]os.FileInfo, error) {
+	dir, err := fs.abs(path)
+	if err != nil {
+		return nil, err
+	}
+
+	return readDir(dir)
+}
+
+func (fs *BoundOS) Rename(from, to string) error {
+	f, err := fs.abs(from)
+	if err != nil {
+		return err
+	}
+	t, err := fs.abs(to)
+	if err != nil {
+		return err
+	}
+
+	// MkdirAll for target name.
+	if err := fs.createDir(t); err != nil {
+		return err
+	}
+
+	return os.Rename(f, t)
+}
+
+func (fs *BoundOS) MkdirAll(path string, perm os.FileMode) error {
+	dir, err := fs.abs(path)
+	if err != nil {
+		return err
+	}
+	return os.MkdirAll(dir, perm)
+}
+
+func (fs *BoundOS) Open(filename string) (billy.File, error) {
+	return fs.OpenFile(filename, os.O_RDONLY, 0)
+}
+
+func (fs *BoundOS) Stat(filename string) (os.FileInfo, error) {
+	filename, err := fs.abs(filename)
+	if err != nil {
+		return nil, err
+	}
+	return os.Stat(filename)
+}
+
+func (fs *BoundOS) Remove(filename string) error {
+	fn, err := fs.abs(filename)
+	if err != nil {
+		return err
+	}
+	return os.Remove(fn)
+}
+
+// TempFile creates a temporary file. If dir is empty, the file
+// will be created within the OS Temporary dir. If dir is provided
+// it must descend from the current base dir.
+func (fs *BoundOS) TempFile(dir, prefix string) (billy.File, error) {
+	if dir != "" {
+		var err error
+		dir, err = fs.abs(dir)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return tempFile(dir, prefix)
+}
+
+func (fs *BoundOS) Join(elem ...string) string {
+	return filepath.Join(elem...)
+}
+
+func (fs *BoundOS) RemoveAll(path string) error {
+	dir, err := fs.abs(path)
+	if err != nil {
+		return err
+	}
+	return os.RemoveAll(dir)
+}
+
+func (fs *BoundOS) Symlink(target, link string) error {
+	ln, err := fs.abs(link)
+	if err != nil {
+		return err
+	}
+	// MkdirAll for containing dir.
+	if err := fs.createDir(ln); err != nil {
+		return err
+	}
+	return os.Symlink(target, ln)
+}
+
+func (fs *BoundOS) Lstat(filename string) (os.FileInfo, error) {
+	filename = filepath.Clean(filename)
+	if !filepath.IsAbs(filename) {
+		filename = filepath.Join(fs.baseDir, filename)
+	}
+	if ok, err := fs.insideBaseDirEval(filename); !ok {
+		return nil, err
+	}
+	return os.Lstat(filename)
+}
+
+func (fs *BoundOS) Readlink(link string) (string, error) {
+	if !filepath.IsAbs(link) {
+		link = filepath.Clean(filepath.Join(fs.baseDir, link))
+	}
+	if ok, err := fs.insideBaseDirEval(link); !ok {
+		return "", err
+	}
+	return os.Readlink(link)
+}
+
+// Chroot returns a new OS filesystem, with the base dir set to the
+// result of joining the provided path with the underlying base dir.
+func (fs *BoundOS) Chroot(path string) (billy.Filesystem, error) {
+	joined, err := securejoin.SecureJoin(fs.baseDir, path)
+	if err != nil {
+		return nil, err
+	}
+	return New(joined), nil
+}
+
+// Root returns the current base dir of the billy.Filesystem.
+// This is required in order for this implementation to be a drop-in
+// replacement for other upstream implementations (e.g. memory and osfs).
+func (fs *BoundOS) Root() string {
+	return fs.baseDir
+}
+
+func (fs *BoundOS) createDir(fullpath string) error {
+	dir := filepath.Dir(fullpath)
+	if dir != "." {
+		if err := os.MkdirAll(dir, defaultDirectoryMode); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// abs transforms filename to an absolute path, taking into account the base dir.
+// Relative paths won't be allowed to ascend the base dir, so `../file` will become
+// `/working-dir/file`.
+//
+// Note that if filename is a symlink, the returned address will be the target of the
+// symlink.
+func (fs *BoundOS) abs(filename string) (string, error) {
+	if filename == fs.baseDir {
+		filename = string(filepath.Separator)
+	}
+
+	path, err := securejoin.SecureJoin(fs.baseDir, filename)
+	if err != nil {
+		return "", nil
+	}
+
+	if fs.deduplicatePath {
+		vol := filepath.VolumeName(fs.baseDir)
+		dup := filepath.Join(fs.baseDir, fs.baseDir[len(vol):])
+		if strings.HasPrefix(path, dup+string(filepath.Separator)) {
+			return fs.abs(path[len(dup):])
+		}
+	}
+	return path, nil
+}
+
+// insideBaseDir checks whether filename is located within
+// the fs.baseDir.
+func (fs *BoundOS) insideBaseDir(filename string) (bool, error) {
+	if filename == fs.baseDir {
+		return true, nil
+	}
+	if !strings.HasPrefix(filename, fs.baseDir+string(filepath.Separator)) {
+		return false, fmt.Errorf("path outside base dir")
+	}
+	return true, nil
+}
+
+// insideBaseDirEval checks whether filename is contained within
+// a dir that is within the fs.baseDir, by first evaluating any symlinks
+// that either filename or fs.baseDir may contain.
+func (fs *BoundOS) insideBaseDirEval(filename string) (bool, error) {
+	dir, err := filepath.EvalSymlinks(filepath.Dir(filename))
+	if dir == "" || os.IsNotExist(err) {
+		dir = filepath.Dir(filename)
+	}
+	wd, err := filepath.EvalSymlinks(fs.baseDir)
+	if wd == "" || os.IsNotExist(err) {
+		wd = fs.baseDir
+	}
+	if filename != wd && dir != wd && !strings.HasPrefix(dir, wd+string(filepath.Separator)) {
+		return false, fmt.Errorf("path outside base dir")
+	}
+	return true, nil
+}

vendor/github.com/go-git/go-billy/v5/osfs/os_chroot.go

@@ -0,0 +1,112 @@
+//go:build !js
+// +build !js
+
+package osfs
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/go-git/go-billy/v5"
+	"github.com/go-git/go-billy/v5/helper/chroot"
+)
+
+// ChrootOS is a legacy filesystem based on a "soft chroot" of the os filesystem.
+// Although this is still the default os filesystem, consider using BoundOS instead.
+//
+// Behaviours of note:
+//  1. A "soft chroot" translates the base dir to "/" for the purposes of the
+//     fs abstraction.
+//  2. Symlinks targets may be modified to be kept within the chroot bounds.
+//  3. Some file modes does not pass-through the fs abstraction.
+//  4. The combination of 1 and 2 may cause go-git to think that a Git repository
+//     is dirty, when in fact it isn't.
+type ChrootOS struct{}
+
+func newChrootOS(baseDir string) billy.Filesystem {
+	return chroot.New(&ChrootOS{}, baseDir)
+}
+
+func (fs *ChrootOS) Create(filename string) (billy.File, error) {
+	return fs.OpenFile(filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, defaultCreateMode)
+}
+
+func (fs *ChrootOS) OpenFile(filename string, flag int, perm os.FileMode) (billy.File, error) {
+	return openFile(filename, flag, perm, fs.createDir)
+}
+
+func (fs *ChrootOS) createDir(fullpath string) error {
+	dir := filepath.Dir(fullpath)
+	if dir != "." {
+		if err := os.MkdirAll(dir, defaultDirectoryMode); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (fs *ChrootOS) ReadDir(dir string) ([]os.FileInfo, error) {
+	return readDir(dir)
+}
+
+func (fs *ChrootOS) Rename(from, to string) error {
+	if err := fs.createDir(to); err != nil {
+		return err
+	}
+
+	return rename(from, to)
+}
+
+func (fs *ChrootOS) MkdirAll(path string, perm os.FileMode) error {
+	return os.MkdirAll(path, defaultDirectoryMode)
+}
+
+func (fs *ChrootOS) Open(filename string) (billy.File, error) {
+	return fs.OpenFile(filename, os.O_RDONLY, 0)
+}
+
+func (fs *ChrootOS) Stat(filename string) (os.FileInfo, error) {
+	return os.Stat(filename)
+}
+
+func (fs *ChrootOS) Remove(filename string) error {
+	return os.Remove(filename)
+}
+
+func (fs *ChrootOS) TempFile(dir, prefix string) (billy.File, error) {
+	if err := fs.createDir(dir + string(os.PathSeparator)); err != nil {
+		return nil, err
+	}
+
+	return tempFile(dir, prefix)
+}
+
+func (fs *ChrootOS) Join(elem ...string) string {
+	return filepath.Join(elem...)
+}
+
+func (fs *ChrootOS) RemoveAll(path string) error {
+	return os.RemoveAll(filepath.Clean(path))
+}
+
+func (fs *ChrootOS) Lstat(filename string) (os.FileInfo, error) {
+	return os.Lstat(filepath.Clean(filename))
+}
+
+func (fs *ChrootOS) Symlink(target, link string) error {
+	if err := fs.createDir(link); err != nil {
+		return err
+	}
+
+	return os.Symlink(target, link)
+}
+
+func (fs *ChrootOS) Readlink(link string) (string, error) {
+	return os.Readlink(link)
+}
+
+// Capabilities implements the Capable interface.
+func (fs *ChrootOS) Capabilities() billy.Capability {
+	return billy.DefaultCapabilities
+}

vendor/github.com/go-git/go-billy/v5/osfs/os_js.go

@@ -0,0 +1,25 @@
+//go:build js
+// +build js
+
+package osfs
+
+import (
+	"github.com/go-git/go-billy/v5"
+	"github.com/go-git/go-billy/v5/helper/chroot"
+	"github.com/go-git/go-billy/v5/memfs"
+)
+
+// globalMemFs is the global memory fs
+var globalMemFs = memfs.New()
+
+// Default Filesystem representing the root of in-memory filesystem for a
+// js/wasm environment.
+var Default = memfs.New()
+
+// New returns a new OS filesystem.
+func New(baseDir string, _ ...Option) billy.Filesystem {
+	return chroot.New(Default, Default.Join("/", baseDir))
+}
+
+type options struct {
+}

vendor/github.com/go-git/go-billy/v5/osfs/os_options.go

@@ -0,0 +1,3 @@
+package osfs
+
+type Option func(*options)

vendor/github.com/go-git/go-billy/v5/osfs/os_plan9.go

@@ -0,0 +1,91 @@
+//go:build plan9
+// +build plan9
+
+package osfs
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"syscall"
+)
+
+func (f *file) Lock() error {
+	// Plan 9 uses a mode bit instead of explicit lock/unlock syscalls.
+	//
+	// Per http://man.cat-v.org/plan_9/5/stat: “Exclusive use files may be open
+	// for I/O by only one fid at a time across all clients of the server. If a
+	// second open is attempted, it draws an error.”
+	//
+	// There is no obvious way to implement this function using the exclusive use bit.
+	// See https://golang.org/src/cmd/go/internal/lockedfile/lockedfile_plan9.go
+	// for how file locking is done by the go tool on Plan 9.
+	return nil
+}
+
+func (f *file) Unlock() error {
+	return nil
+}
+
+func rename(from, to string) error {
+	// If from and to are in different directories, copy the file
+	// since Plan 9 does not support cross-directory rename.
+	if filepath.Dir(from) != filepath.Dir(to) {
+		fi, err := os.Stat(from)
+		if err != nil {
+			return &os.LinkError{"rename", from, to, err}
+		}
+		if fi.Mode().IsDir() {
+			return &os.LinkError{"rename", from, to, syscall.EISDIR}
+		}
+		fromFile, err := os.Open(from)
+		if err != nil {
+			return &os.LinkError{"rename", from, to, err}
+		}
+		toFile, err := os.OpenFile(to, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, fi.Mode())
+		if err != nil {
+			return &os.LinkError{"rename", from, to, err}
+		}
+		_, err = io.Copy(toFile, fromFile)
+		if err != nil {
+			return &os.LinkError{"rename", from, to, err}
+		}
+
+		// Copy mtime and mode from original file.
+		// We need only one syscall if we avoid os.Chmod and os.Chtimes.
+		dir := fi.Sys().(*syscall.Dir)
+		var d syscall.Dir
+		d.Null()
+		d.Mtime = dir.Mtime
+		d.Mode = dir.Mode
+		if err = dirwstat(to, &d); err != nil {
+			return &os.LinkError{"rename", from, to, err}
+		}
+
+		// Remove original file.
+		err = os.Remove(from)
+		if err != nil {
+			return &os.LinkError{"rename", from, to, err}
+		}
+		return nil
+	}
+	return os.Rename(from, to)
+}
+
+func dirwstat(name string, d *syscall.Dir) error {
+	var buf [syscall.STATFIXLEN]byte
+
+	n, err := d.Marshal(buf[:])
+	if err != nil {
+		return &os.PathError{"dirwstat", name, err}
+	}
+	if err = syscall.Wstat(name, buf[:n]); err != nil {
+		return &os.PathError{"dirwstat", name, err}
+	}
+	return nil
+}
+
+func umask(new int) func() {
+	return func() {
+	}
+}

vendor/github.com/go-git/go-billy/v5/osfs/os_posix.go

@@ -0,0 +1,38 @@
+//go:build !plan9 && !windows && !js
+// +build !plan9,!windows,!js
+
+package osfs
+
+import (
+	"os"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+func (f *file) Lock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	return unix.Flock(int(f.File.Fd()), unix.LOCK_EX)
+}
+
+func (f *file) Unlock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	return unix.Flock(int(f.File.Fd()), unix.LOCK_UN)
+}
+
+func rename(from, to string) error {
+	return os.Rename(from, to)
+}
+
+// umask sets umask to a new value, and returns a func which allows the
+// caller to reset it back to what it was originally.
+func umask(new int) func() {
+	old := syscall.Umask(new)
+	return func() {
+		syscall.Umask(old)
+	}
+}

vendor/github.com/go-git/go-billy/v5/osfs/os_windows.go

@@ -0,0 +1,58 @@
+//go:build windows
+// +build windows
+
+package osfs
+
+import (
+	"os"
+	"runtime"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+var (
+	kernel32DLL    = windows.NewLazySystemDLL("kernel32.dll")
+	lockFileExProc = kernel32DLL.NewProc("LockFileEx")
+	unlockFileProc = kernel32DLL.NewProc("UnlockFile")
+)
+
+const (
+	lockfileExclusiveLock = 0x2
+)
+
+func (f *file) Lock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	var overlapped windows.Overlapped
+	// err is always non-nil as per sys/windows semantics.
+	ret, _, err := lockFileExProc.Call(f.File.Fd(), lockfileExclusiveLock, 0, 0xFFFFFFFF, 0,
+		uintptr(unsafe.Pointer(&overlapped)))
+	runtime.KeepAlive(&overlapped)
+	if ret == 0 {
+		return err
+	}
+	return nil
+}
+
+func (f *file) Unlock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	// err is always non-nil as per sys/windows semantics.
+	ret, _, err := unlockFileProc.Call(f.File.Fd(), 0, 0, 0xFFFFFFFF, 0)
+	if ret == 0 {
+		return err
+	}
+	return nil
+}
+
+func rename(from, to string) error {
+	return os.Rename(from, to)
+}
+
+func umask(new int) func() {
+	return func() {
+	}
+}

vendor/github.com/go-git/go-billy/v5/util/glob.go

@@ -0,0 +1,111 @@
+package util
+
+import (
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/go-git/go-billy/v5"
+)
+
+// Glob returns the names of all files matching pattern or nil
+// if there is no matching file. The syntax of patterns is the same
+// as in Match. The pattern may describe hierarchical names such as
+// /usr/*/bin/ed (assuming the Separator is '/').
+//
+// Glob ignores file system errors such as I/O errors reading directories.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
+//
+// Function originally from https://golang.org/src/path/filepath/match_test.go
+func Glob(fs billy.Filesystem, pattern string) (matches []string, err error) {
+	if !hasMeta(pattern) {
+		if _, err = fs.Lstat(pattern); err != nil {
+			return nil, nil
+		}
+		return []string{pattern}, nil
+	}
+
+	dir, file := filepath.Split(pattern)
+	// Prevent infinite recursion. See issue 15879.
+	if dir == pattern {
+		return nil, filepath.ErrBadPattern
+	}
+
+	var m []string
+	m, err = Glob(fs, cleanGlobPath(dir))
+	if err != nil {
+		return
+	}
+	for _, d := range m {
+		matches, err = glob(fs, d, file, matches)
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// cleanGlobPath prepares path for glob matching.
+func cleanGlobPath(path string) string {
+	switch path {
+	case "":
+		return "."
+	case string(filepath.Separator):
+		// do nothing to the path
+		return path
+	default:
+		return path[0 : len(path)-1] // chop off trailing separator
+	}
+}
+
+// glob searches for files matching pattern in the directory dir
+// and appends them to matches. If the directory cannot be
+// opened, it returns the existing matches. New matches are
+// added in lexicographical order.
+func glob(fs billy.Filesystem, dir, pattern string, matches []string) (m []string, e error) {
+	m = matches
+	fi, err := fs.Stat(dir)
+	if err != nil {
+		return
+	}
+
+	if !fi.IsDir() {
+		return
+	}
+
+	names, _ := readdirnames(fs, dir)
+	sort.Strings(names)
+
+	for _, n := range names {
+		matched, err := filepath.Match(pattern, n)
+		if err != nil {
+			return m, err
+		}
+		if matched {
+			m = append(m, filepath.Join(dir, n))
+		}
+	}
+	return
+}
+
+// hasMeta reports whether path contains any of the magic characters
+// recognized by Match.
+func hasMeta(path string) bool {
+	// TODO(niemeyer): Should other magic characters be added here?
+	return strings.ContainsAny(path, "*?[")
+}
+
+func readdirnames(fs billy.Filesystem, dir string) ([]string, error) {
+	files, err := fs.ReadDir(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	var names []string
+	for _, file := range files {
+		names = append(names, file.Name())
+	}
+
+	return names, nil
+}

vendor/github.com/go-git/go-billy/v5/util/util.go

@@ -0,0 +1,282 @@
+package util
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/go-git/go-billy/v5"
+)
+
+// RemoveAll removes path and any children it contains. It removes everything it
+// can but returns the first error it encounters. If the path does not exist,
+// RemoveAll returns nil (no error).
+func RemoveAll(fs billy.Basic, path string) error {
+	fs, path = getUnderlyingAndPath(fs, path)
+
+	if r, ok := fs.(removerAll); ok {
+		return r.RemoveAll(path)
+	}
+
+	return removeAll(fs, path)
+}
+
+type removerAll interface {
+	RemoveAll(string) error
+}
+
+func removeAll(fs billy.Basic, path string) error {
+	// This implementation is adapted from os.RemoveAll.
+
+	// Simple case: if Remove works, we're done.
+	err := fs.Remove(path)
+	if err == nil || os.IsNotExist(err) {
+		return nil
+	}
+
+	// Otherwise, is this a directory we need to recurse into?
+	dir, serr := fs.Stat(path)
+	if serr != nil {
+		if os.IsNotExist(serr) {
+			return nil
+		}
+
+		return serr
+	}
+
+	if !dir.IsDir() {
+		// Not a directory; return the error from Remove.
+		return err
+	}
+
+	dirfs, ok := fs.(billy.Dir)
+	if !ok {
+		return billy.ErrNotSupported
+	}
+
+	// Directory.
+	fis, err := dirfs.ReadDir(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			// Race. It was deleted between the Lstat and Open.
+			// Return nil per RemoveAll's docs.
+			return nil
+		}
+
+		return err
+	}
+
+	// Remove contents & return first error.
+	err = nil
+	for _, fi := range fis {
+		cpath := fs.Join(path, fi.Name())
+		err1 := removeAll(fs, cpath)
+		if err == nil {
+			err = err1
+		}
+	}
+
+	// Remove directory.
+	err1 := fs.Remove(path)
+	if err1 == nil || os.IsNotExist(err1) {
+		return nil
+	}
+
+	if err == nil {
+		err = err1
+	}
+
+	return err
+
+}
+
+// WriteFile writes data to a file named by filename in the given filesystem.
+// If the file does not exist, WriteFile creates it with permissions perm;
+// otherwise WriteFile truncates it before writing.
+func WriteFile(fs billy.Basic, filename string, data []byte, perm os.FileMode) error {
+	f, err := fs.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+
+	n, err := f.Write(data)
+	if err == nil && n < len(data) {
+		err = io.ErrShortWrite
+	}
+
+	if err1 := f.Close(); err == nil {
+		err = err1
+	}
+
+	return err
+}
+
+// Random number state.
+// We generate random temporary file names so that there's a good
+// chance the file doesn't exist yet - keeps the number of tries in
+// TempFile to a minimum.
+var rand uint32
+var randmu sync.Mutex
+
+func reseed() uint32 {
+	return uint32(time.Now().UnixNano() + int64(os.Getpid()))
+}
+
+func nextSuffix() string {
+	randmu.Lock()
+	r := rand
+	if r == 0 {
+		r = reseed()
+	}
+	r = r*1664525 + 1013904223 // constants from Numerical Recipes
+	rand = r
+	randmu.Unlock()
+	return strconv.Itoa(int(1e9 + r%1e9))[1:]
+}
+
+// TempFile creates a new temporary file in the directory dir with a name
+// beginning with prefix, opens the file for reading and writing, and returns
+// the resulting *os.File. If dir is the empty string, TempFile uses the default
+// directory for temporary files (see os.TempDir). Multiple programs calling
+// TempFile simultaneously will not choose the same file. The caller can use
+// f.Name() to find the pathname of the file. It is the caller's responsibility
+// to remove the file when no longer needed.
+func TempFile(fs billy.Basic, dir, prefix string) (f billy.File, err error) {
+	// This implementation is based on stdlib ioutil.TempFile.
+	if dir == "" {
+		dir = getTempDir(fs)
+	}
+
+	nconflict := 0
+	for i := 0; i < 10000; i++ {
+		name := filepath.Join(dir, prefix+nextSuffix())
+		f, err = fs.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
+		if os.IsExist(err) {
+			if nconflict++; nconflict > 10 {
+				randmu.Lock()
+				rand = reseed()
+				randmu.Unlock()
+			}
+			continue
+		}
+		break
+	}
+	return
+}
+
+// TempDir creates a new temporary directory in the directory dir
+// with a name beginning with prefix and returns the path of the
+// new directory. If dir is the empty string, TempDir uses the
+// default directory for temporary files (see os.TempDir).
+// Multiple programs calling TempDir simultaneously
+// will not choose the same directory. It is the caller's responsibility
+// to remove the directory when no longer needed.
+func TempDir(fs billy.Dir, dir, prefix string) (name string, err error) {
+	// This implementation is based on stdlib ioutil.TempDir
+
+	if dir == "" {
+		dir = getTempDir(fs.(billy.Basic))
+	}
+
+	nconflict := 0
+	for i := 0; i < 10000; i++ {
+		try := filepath.Join(dir, prefix+nextSuffix())
+		err = fs.MkdirAll(try, 0700)
+		if os.IsExist(err) {
+			if nconflict++; nconflict > 10 {
+				randmu.Lock()
+				rand = reseed()
+				randmu.Unlock()
+			}
+			continue
+		}
+		if os.IsNotExist(err) {
+			if _, err := os.Stat(dir); os.IsNotExist(err) {
+				return "", err
+			}
+		}
+		if err == nil {
+			name = try
+		}
+		break
+	}
+	return
+}
+
+func getTempDir(fs billy.Basic) string {
+	ch, ok := fs.(billy.Chroot)
+	if !ok || ch.Root() == "" || ch.Root() == "/" || ch.Root() == string(filepath.Separator) {
+		return os.TempDir()
+	}
+
+	return ".tmp"
+}
+
+type underlying interface {
+	Underlying() billy.Basic
+}
+
+func getUnderlyingAndPath(fs billy.Basic, path string) (billy.Basic, string) {
+	u, ok := fs.(underlying)
+	if !ok {
+		return fs, path
+	}
+	if ch, ok := fs.(billy.Chroot); ok {
+		path = fs.Join(ch.Root(), path)
+	}
+
+	return u.Underlying(), path
+}
+
+// ReadFile reads the named file and returns the contents from the given filesystem.
+// A successful call returns err == nil, not err == EOF.
+// Because ReadFile reads the whole file, it does not treat an EOF from Read
+// as an error to be reported.
+func ReadFile(fs billy.Basic, name string) ([]byte, error) {
+	f, err := fs.Open(name)
+	if err != nil {
+		return nil, err
+	}
+
+	defer f.Close()
+
+	var size int
+	if info, err := fs.Stat(name); err == nil {
+		size64 := info.Size()
+		if int64(int(size64)) == size64 {
+			size = int(size64)
+		}
+	}
+
+	size++ // one byte for final read at EOF
+	// If a file claims a small size, read at least 512 bytes.
+	// In particular, files in Linux's /proc claim size 0 but
+	// then do not work right if read in small pieces,
+	// so an initial read of 1 byte would not work correctly.
+
+	if size < 512 {
+		size = 512
+	}
+
+	data := make([]byte, 0, size)
+	for {
+		if len(data) >= cap(data) {
+			d := append(data[:cap(data)], 0)
+			data = d[:len(data)]
+		}
+
+		n, err := f.Read(data[len(data):cap(data)])
+		data = data[:len(data)+n]
+
+		if err != nil {
+			if err == io.EOF {
+				err = nil
+			}
+
+			return data, err
+		}
+	}
+}

vendor/github.com/go-git/go-billy/v5/util/walk.go

@@ -0,0 +1,72 @@
+package util
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/go-git/go-billy/v5"
+)
+
+// walk recursively descends path, calling walkFn
+// adapted from https://golang.org/src/path/filepath/path.go
+func walk(fs billy.Filesystem, path string, info os.FileInfo, walkFn filepath.WalkFunc) error {
+	if !info.IsDir() {
+		return walkFn(path, info, nil)
+	}
+
+	names, err := readdirnames(fs, path)
+	err1 := walkFn(path, info, err)
+	// If err != nil, walk can't walk into this directory.
+	// err1 != nil means walkFn want walk to skip this directory or stop walking.
+	// Therefore, if one of err and err1 isn't nil, walk will return.
+	if err != nil || err1 != nil {
+		// The caller's behavior is controlled by the return value, which is decided
+		// by walkFn. walkFn may ignore err and return nil.
+		// If walkFn returns SkipDir, it will be handled by the caller.
+		// So walk should return whatever walkFn returns.
+		return err1
+	}
+
+	for _, name := range names {
+		filename := filepath.Join(path, name)
+		fileInfo, err := fs.Lstat(filename)
+		if err != nil {
+			if err := walkFn(filename, fileInfo, err); err != nil && err != filepath.SkipDir {
+				return err
+			}
+		} else {
+			err = walk(fs, filename, fileInfo, walkFn)
+			if err != nil {
+				if !fileInfo.IsDir() || err != filepath.SkipDir {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+// Walk walks the file tree rooted at root, calling fn for each file or
+// directory in the tree, including root. All errors that arise visiting files
+// and directories are filtered by fn: see the WalkFunc documentation for
+// details.
+//
+// The files are walked in lexical order, which makes the output deterministic
+// but requires Walk to read an entire directory into memory before proceeding
+// to walk that directory. Walk does not follow symbolic links.
+//
+// Function adapted from https://github.com/golang/go/blob/3b770f2ccb1fa6fecc22ea822a19447b10b70c5c/src/path/filepath/path.go#L500
+func Walk(fs billy.Filesystem, root string, walkFn filepath.WalkFunc) error {
+	info, err := fs.Lstat(root)
+	if err != nil {
+		err = walkFn(root, nil, err)
+	} else {
+		err = walk(fs, root, info, walkFn)
+	}
+
+	if err == filepath.SkipDir {
+		return nil
+	}
+
+	return err
+}

vendor/github.com/go-git/go-git/v5/.gitignore

@@ -0,0 +1,7 @@
+coverage.out
+*~
+coverage.txt
+profile.out
+.tmp/
+.git-dist/
+.vscode

vendor/github.com/go-git/go-git/v5/CODE_OF_CONDUCT.md

@@ -0,0 +1,74 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, gender identity and expression, level of experience,
+education, socio-economic status, nationality, personal appearance, race,
+religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at conduct@sourced.tech. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+

vendor/github.com/go-git/go-git/v5/COMPATIBILITY.md

@@ -0,0 +1,233 @@
+# Supported Features
+
+Here is a non-comprehensive table of git commands and features and their
+compatibility status with go-git.
+
+## Getting and creating repositories
+
+| Feature | Sub-feature                                                                                                        | Status | Notes | Examples                                                                                                                                                                                                            |
+| ------- | ------------------------------------------------------------------------------------------------------------------ | ------ | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `init`  |                                                                                                                    | ✅     |       |                                                                                                                                                                                                                     |
+| `init`  | `--bare`                                                                                                           | ✅     |       |                                                                                                                                                                                                                     |
+| `init`  | `--template` <br/> `--separate-git-dir` <br/> `--shared`                                                           | ❌     |       |                                                                                                                                                                                                                     |
+| `clone` |                                                                                                                    | ✅     |       | - [PlainClone](_examples/clone/main.go)                                                                                                                                                                             |
+| `clone` | Authentication: <br/> - none <br/> - access token <br/> - username + password <br/> - ssh                          | ✅     |       | - [clone ssh](_examples/clone/auth/ssh/main.go) <br/> - [clone access token](_examples/clone/auth/basic/access_token/main.go) <br/> - [clone user + password](_examples/clone/auth/basic/username_password/main.go) |
+| `clone` | `--progress` <br/> `--single-branch` <br/> `--depth` <br/> `--origin` <br/> `--recurse-submodules` <br/>`--shared` | ✅     |       | - [recurse submodules](_examples/clone/main.go) <br/> - [progress](_examples/progress/main.go)                                                                                                                      |
+
+## Basic snapshotting
+
+| Feature  | Sub-feature | Status | Notes                                                    | Examples                             |
+| -------- | ----------- | ------ | -------------------------------------------------------- | ------------------------------------ |
+| `add`    |             | ✅     | Plain add is supported. Any other flags aren't supported |                                      |
+| `status` |             | ✅     |                                                          |                                      |
+| `commit` |             | ✅     |                                                          | - [commit](_examples/commit/main.go) |
+| `reset`  |             | ✅     |                                                          |                                      |
+| `rm`     |             | ✅     |                                                          |                                      |
+| `mv`     |             | ✅     |                                                          |                                      |
+
+## Branching and merging
+
+| Feature     | Sub-feature | Status       | Notes                                   | Examples                                                                                        |
+| ----------- | ----------- | ------------ | --------------------------------------- | ----------------------------------------------------------------------------------------------- |
+| `branch`    |             | ✅           |                                         | - [branch](_examples/branch/main.go)                                                            |
+| `checkout`  |             | ✅           | Basic usages of checkout are supported. | - [checkout](_examples/checkout/main.go)                                                        |
+| `merge`     |             | ⚠️ (partial) | Fast-forward only                       |                                                                                                 |
+| `mergetool` |             | ❌           |                                         |                                                                                                 |
+| `stash`     |             | ❌           |                                         |                                                                                                 |
+| `tag`       |             | ✅           |                                         | - [tag](_examples/tag/main.go) <br/> - [tag create and push](_examples/tag-create-push/main.go) |
+
+## Sharing and updating projects
+
+| Feature     | Sub-feature | Status | Notes                                                                   | Examples                                   |
+| ----------- | ----------- | ------ | ----------------------------------------------------------------------- | ------------------------------------------ |
+| `fetch`     |             | ✅     |                                                                         |                                            |
+| `pull`      |             | ✅     | Only supports merges where the merge can be resolved as a fast-forward. | - [pull](_examples/pull/main.go)           |
+| `push`      |             | ✅     |                                                                         | - [push](_examples/push/main.go)           |
+| `remote`    |             | ✅     |                                                                         | - [remotes](_examples/remotes/main.go)     |
+| `submodule` |             | ✅     |                                                                         | - [submodule](_examples/submodule/main.go) |
+| `submodule` | deinit      | ❌     |                                                                         |                                            |
+
+## Inspection and comparison
+
+| Feature    | Sub-feature | Status    | Notes | Examples                       |
+| ---------- | ----------- | --------- | ----- | ------------------------------ |
+| `show`     |             | ✅        |       |                                |
+| `log`      |             | ✅        |       | - [log](_examples/log/main.go) |
+| `shortlog` |             | (see log) |       |                                |
+| `describe` |             | ❌        |       |                                |
+
+## Patching
+
+| Feature       | Sub-feature | Status | Notes                                                | Examples |
+| ------------- | ----------- | ------ | ---------------------------------------------------- | -------- |
+| `apply`       |             | ❌     |                                                      |          |
+| `cherry-pick` |             | ❌     |                                                      |          |
+| `diff`        |             | ✅     | Patch object with UnifiedDiff output representation. |          |
+| `rebase`      |             | ❌     |                                                      |          |
+| `revert`      |             | ❌     |                                                      |          |
+
+## Debugging
+
+| Feature  | Sub-feature | Status | Notes | Examples                           |
+| -------- | ----------- | ------ | ----- | ---------------------------------- |
+| `bisect` |             | ❌     |       |                                    |
+| `blame`  |             | ✅     |       | - [blame](_examples/blame/main.go) |
+| `grep`   |             | ✅     |       |                                    |
+
+## Email
+
+| Feature        | Sub-feature | Status | Notes | Examples |
+| -------------- | ----------- | ------ | ----- | -------- |
+| `am`           |             | ❌     |       |          |
+| `apply`        |             | ❌     |       |          |
+| `format-patch` |             | ❌     |       |          |
+| `send-email`   |             | ❌     |       |          |
+| `request-pull` |             | ❌     |       |          |
+
+## External systems
+
+| Feature       | Sub-feature | Status | Notes | Examples |
+| ------------- | ----------- | ------ | ----- | -------- |
+| `svn`         |             | ❌     |       |          |
+| `fast-import` |             | ❌     |       |          |
+| `lfs`         |             | ❌     |       |          |
+
+## Administration
+
+| Feature         | Sub-feature | Status | Notes | Examples |
+| --------------- | ----------- | ------ | ----- | -------- |
+| `clean`         |             | ✅     |       |          |
+| `gc`            |             | ❌     |       |          |
+| `fsck`          |             | ❌     |       |          |
+| `reflog`        |             | ❌     |       |          |
+| `filter-branch` |             | ❌     |       |          |
+| `instaweb`      |             | ❌     |       |          |
+| `archive`       |             | ❌     |       |          |
+| `bundle`        |             | ❌     |       |          |
+| `prune`         |             | ❌     |       |          |
+| `repack`        |             | ❌     |       |          |
+
+## Server admin
+
+| Feature              | Sub-feature | Status | Notes | Examples                                  |
+| -------------------- | ----------- | ------ | ----- | ----------------------------------------- |
+| `daemon`             |             | ❌     |       |                                           |
+| `update-server-info` |             | ✅     |       | [cli](./cli/go-git/update_server_info.go) |
+
+## Advanced
+
+| Feature    | Sub-feature | Status      | Notes | Examples |
+| ---------- | ----------- | ----------- | ----- | -------- |
+| `notes`    |             | ❌          |       |          |
+| `replace`  |             | ❌          |       |          |
+| `worktree` |             | ❌          |       |          |
+| `annotate` |             | (see blame) |       |          |
+
+## GPG
+
+| Feature             | Sub-feature | Status | Notes | Examples |
+| ------------------- | ----------- | ------ | ----- | -------- |
+| `git-verify-commit` |             | ✅     |       |          |
+| `git-verify-tag`    |             | ✅     |       |          |
+
+## Plumbing commands
+
+| Feature         | Sub-feature                           | Status       | Notes                                               | Examples                                     |
+| --------------- | ------------------------------------- | ------------ | --------------------------------------------------- | -------------------------------------------- |
+| `cat-file`      |                                       | ✅           |                                                     |                                              |
+| `check-ignore`  |                                       | ❌           |                                                     |                                              |
+| `commit-tree`   |                                       | ❌           |                                                     |                                              |
+| `count-objects` |                                       | ❌           |                                                     |                                              |
+| `diff-index`    |                                       | ❌           |                                                     |                                              |
+| `for-each-ref`  |                                       | ✅           |                                                     |                                              |
+| `hash-object`   |                                       | ✅           |                                                     |                                              |
+| `ls-files`      |                                       | ✅           |                                                     |                                              |
+| `ls-remote`     |                                       | ✅           |                                                     | - [ls-remote](_examples/ls-remote/main.go)   |
+| `merge-base`    | `--independent` <br/> `--is-ancestor` | ⚠️ (partial) | Calculates the merge-base only between two commits. | - [merge-base](_examples/merge_base/main.go) |
+| `merge-base`    | `--fork-point` <br/> `--octopus`      | ❌           |                                                     |                                              |
+| `read-tree`     |                                       | ❌           |                                                     |                                              |
+| `rev-list`      |                                       | ✅           |                                                     |                                              |
+| `rev-parse`     |                                       | ❌           |                                                     |                                              |
+| `show-ref`      |                                       | ✅           |                                                     |                                              |
+| `symbolic-ref`  |                                       | ✅           |                                                     |                                              |
+| `update-index`  |                                       | ❌           |                                                     |                                              |
+| `update-ref`    |                                       | ❌           |                                                     |                                              |
+| `verify-pack`   |                                       | ❌           |                                                     |                                              |
+| `write-tree`    |                                       | ❌           |                                                     |                                              |
+
+## Indexes and Git Protocols
+
+| Feature              | Version                                                                         | Status | Notes |
+| -------------------- | ------------------------------------------------------------------------------- | ------ | ----- |
+| index                | [v1](https://github.com/git/git/blob/master/Documentation/gitformat-index.txt)  | ❌     |       |
+| index                | [v2](https://github.com/git/git/blob/master/Documentation/gitformat-index.txt)  | ✅     |       |
+| index                | [v3](https://github.com/git/git/blob/master/Documentation/gitformat-index.txt)  | ❌     |       |
+| pack-protocol        | [v1](https://github.com/git/git/blob/master/Documentation/gitprotocol-pack.txt) | ✅     |       |
+| pack-protocol        | [v2](https://github.com/git/git/blob/master/Documentation/gitprotocol-v2.txt)   | ❌     |       |
+| multi-pack-index     | [v1](https://github.com/git/git/blob/master/Documentation/gitformat-pack.txt)   | ❌     |       |
+| pack-\*.rev files    | [v1](https://github.com/git/git/blob/master/Documentation/gitformat-pack.txt)   | ❌     |       |
+| pack-\*.mtimes files | [v1](https://github.com/git/git/blob/master/Documentation/gitformat-pack.txt)   | ❌     |       |
+| cruft packs          |                                                                                 | ❌     |       |
+
+## Capabilities
+
+| Feature                        | Status       | Notes |
+| ------------------------------ | ------------ | ----- |
+| `multi_ack`                    | ❌           |       |
+| `multi_ack_detailed`           | ❌           |       |
+| `no-done`                      | ❌           |       |
+| `thin-pack`                    | ❌           |       |
+| `side-band`                    | ⚠️ (partial) |       |
+| `side-band-64k`                | ⚠️ (partial) |       |
+| `ofs-delta`                    | ✅           |       |
+| `agent`                        | ✅           |       |
+| `object-format`                | ❌           |       |
+| `symref`                       | ✅           |       |
+| `shallow`                      | ✅           |       |
+| `deepen-since`                 | ✅           |       |
+| `deepen-not`                   | ❌           |       |
+| `deepen-relative`              | ❌           |       |
+| `no-progress`                  | ✅           |       |
+| `include-tag`                  | ✅           |       |
+| `report-status`                | ✅           |       |
+| `report-status-v2`             | ❌           |       |
+| `delete-refs`                  | ✅           |       |
+| `quiet`                        | ❌           |       |
+| `atomic`                       | ✅           |       |
+| `push-options`                 | ✅           |       |
+| `allow-tip-sha1-in-want`       | ✅           |       |
+| `allow-reachable-sha1-in-want` | ❌           |       |
+| `push-cert=<nonce>`            | ❌           |       |
+| `filter`                       | ❌           |       |
+| `session-id=<session id>`      | ❌           |       |
+
+## Transport Schemes
+
+| Scheme               | Status       | Notes                                                                  | Examples                                       |
+| -------------------- | ------------ | ---------------------------------------------------------------------- | ---------------------------------------------- |
+| `http(s)://` (dumb)  | ❌           |                                                                        |                                                |
+| `http(s)://` (smart) | ✅           |                                                                        |                                                |
+| `git://`             | ✅           |                                                                        |                                                |
+| `ssh://`             | ✅           |                                                                        |                                                |
+| `file://`            | ⚠️ (partial) | Warning: this is not pure Golang. This shells out to the `git` binary. |                                                |
+| Custom               | ✅           | All existing schemes can be replaced by custom implementations.        | - [custom_http](_examples/custom_http/main.go) |
+
+## SHA256
+
+| Feature  | Sub-feature | Status | Notes                              | Examples                             |
+| -------- | ----------- | ------ | ---------------------------------- | ------------------------------------ |
+| `init`   |             | ✅     | Requires building with tag sha256. | - [init](_examples/sha256/main.go)   |
+| `commit` |             | ✅     | Requires building with tag sha256. | - [commit](_examples/sha256/main.go) |
+| `pull`   |             | ❌     |                                    |                                      |
+| `fetch`  |             | ❌     |                                    |                                      |
+| `push`   |             | ❌     |                                    |                                      |
+
+## Other features
+
+| Feature         | Sub-feature                 | Status | Notes                                          | Examples |
+| --------------- | --------------------------- | ------ | ---------------------------------------------- | -------- |
+| `config`        | `--local`                   | ✅     | Read and write per-repository (`.git/config`). |          |
+| `config`        | `--global` <br/> `--system` | ✅     | Read-only.                                     |          |
+| `gitignore`     |                             | ✅     |                                                |          |
+| `gitattributes` |                             | ✅     |                                                |          |
+| `git-worktree`  |                             | ❌     | Multiple worktrees are not supported.          |          |

vendor/github.com/go-git/go-git/v5/CONTRIBUTING.md

@@ -0,0 +1,46 @@
+# Contributing Guidelines
+
+source{d} go-git project is [Apache 2.0 licensed](LICENSE) and accepts
+contributions via GitHub pull requests.  This document outlines some of the
+conventions on development workflow, commit message formatting, contact points,
+and other resources to make it easier to get your contribution accepted.
+
+## Support Channels
+
+The official support channels, for both users and contributors, are:
+
+- [StackOverflow go-git tag](https://stackoverflow.com/questions/tagged/go-git) for user questions.
+- GitHub [Issues](https://github.com/src-d/go-git/issues)* for bug reports and feature requests.
+
+*Before opening a new issue or submitting a new pull request, it's helpful to
+search the project - it's likely that another user has already reported the
+issue you're facing, or it's a known issue that we're already aware of.
+
+
+## How to Contribute
+
+Pull Requests (PRs) are the main and exclusive way to contribute to the official go-git project.
+In order for a PR to be accepted it needs to pass a list of requirements:
+
+- You should be able to run the same query using `git`. We don't accept features that are not implemented in the official git implementation.
+- The expected behavior must match the [official git implementation](https://github.com/git/git).
+- The actual behavior must be correctly explained with natural language and providing a minimum working example in Go that reproduces it.
+- All PRs must be written in idiomatic Go, formatted according to [gofmt](https://golang.org/cmd/gofmt/), and without any warnings from [go lint](https://github.com/golang/lint) nor [go vet](https://golang.org/cmd/vet/).
+- They should in general include tests, and those shall pass.
+- If the PR is a bug fix, it has to include a suite of unit tests for the new functionality.
+- If the PR is a new feature, it has to come with a suite of unit tests, that tests the new functionality.
+- In any case, all the PRs have to pass the personal evaluation of at least one of the maintainers of go-git.
+
+### Format of the commit message
+
+Every commit message should describe what was changed, under which context and, if applicable, the GitHub issue it relates to:
+
+```
+plumbing: packp, Skip argument validations for unknown capabilities. Fixes #623
+```
+
+The format can be described more formally as follows:
+
+```
+<package>: <subpackage>, <what changed>. [Fixes #<issue-number>]
+```

vendor/github.com/go-git/go-git/v5/EXTENDING.md

@@ -0,0 +1,78 @@
+# Extending go-git
+
+`go-git` was built in a highly extensible manner, which enables some of its functionalities to be changed or extended without the need of changing its codebase. Here are the key extensibility features:
+
+## Dot Git Storers
+
+Dot git storers are the components responsible for storing the Git internal files, including objects and references.
+
+The built-in storer implementations include [memory](storage/memory) and [filesystem](storage/filesystem). The `memory` storer stores all the data in memory, and its use look like this:
+
+```go
+	r, err := git.Init(memory.NewStorage(), nil)
+```
+
+The `filesystem` storer stores the data in the OS filesystem, and can be used as follows:
+
+```go
+    r, err := git.Init(filesystem.NewStorage(osfs.New("/tmp/foo")), nil)
+```
+
+New implementations can be created by implementing the [storage.Storer interface](storage/storer.go#L16).
+
+## Filesystem
+
+Git repository worktrees are managed using a filesystem abstraction based on [go-billy](https://github.com/go-git/go-billy). The Git operations will take place against the specific filesystem implementation. Initialising a repository in Memory can be done as follows:
+
+```go
+	fs := memfs.New()
+	r, err := git.Init(memory.NewStorage(), fs)
+```
+
+The same operation can be done against the OS filesystem:
+
+```go
+    fs := osfs.New("/tmp/foo")
+    r, err := git.Init(memory.NewStorage(), fs)
+```
+
+New filesystems (e.g. cloud based storage) could be created by implementing `go-billy`'s [Filesystem interface](https://github.com/go-git/go-billy/blob/326c59f064021b821a55371d57794fbfb86d4cb3/fs.go#L52).
+
+## Transport Schemes
+
+Git supports various transport schemes, including `http`, `https`, `ssh`, `git`, `file`. `go-git` defines the [transport.Transport interface](plumbing/transport/common.go#L48) to represent them.
+
+The built-in implementations can be replaced by calling `client.InstallProtocol`.
+
+An example of changing the built-in `https` implementation to skip TLS could look like this:
+
+```go
+	customClient := &http.Client{
+		Transport: &http.Transport{
+			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+		},
+	}
+
+	client.InstallProtocol("https", githttp.NewClient(customClient))
+```
+
+Some internal implementations enables code reuse amongst the different transport implementations. Some of these may be made public in the future (e.g. `plumbing/transport/internal/common`).
+
+## Cache
+
+Several different operations across `go-git` lean on caching of objects in order to achieve optimal performance. The caching functionality is defined by the [cache.Object interface](plumbing/cache/common.go#L17).
+
+Two built-in implementations are `cache.ObjectLRU` and `cache.BufferLRU`. However, the caching functionality can be customized by implementing the interface `cache.Object` interface.
+
+## Hash
+
+`go-git` uses the `crypto.Hash` interface to represent hash functions. The built-in implementations are `github.com/pjbgf/sha1cd` for SHA1 and Go's `crypto/SHA256`.
+
+The default hash functions can be changed by calling `hash.RegisterHash`.
+```go
+    func init() {
+        hash.RegisterHash(crypto.SHA1, sha1.New)
+    }
+```
+
+New `SHA1` or `SHA256` hash functions that implement the `hash.RegisterHash` interface can be registered by calling `RegisterHash`.

vendor/github.com/go-git/go-git/v5/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
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+
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+      any Contribution intentionally submitted for inclusion in the Work
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+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/go-git/go-git/v5/Makefile

@@ -0,0 +1,54 @@
+# General
+WORKDIR = $(PWD)
+
+# Go parameters
+GOCMD = go
+GOTEST = $(GOCMD) test 
+
+# Git config
+GIT_VERSION ?=
+GIT_DIST_PATH ?= $(PWD)/.git-dist
+GIT_REPOSITORY = http://github.com/git/git.git
+
+# Coverage
+COVERAGE_REPORT = coverage.out
+COVERAGE_MODE = count
+
+build-git:
+	@if [ -f $(GIT_DIST_PATH)/git ]; then \
+		echo "nothing to do, using cache $(GIT_DIST_PATH)"; \
+	else \
+		git clone $(GIT_REPOSITORY) -b $(GIT_VERSION) --depth 1 --single-branch $(GIT_DIST_PATH); \
+		cd $(GIT_DIST_PATH); \
+		make configure; \
+		./configure; \
+		make all; \
+	fi
+
+test:
+	@echo "running against `git version`"; \
+	$(GOTEST) -race ./...
+	$(GOTEST) -v _examples/common_test.go _examples/common.go --examples
+
+TEMP_REPO := $(shell mktemp)
+test-sha256:
+	$(GOCMD) run -tags sha256 _examples/sha256/main.go $(TEMP_REPO)
+	cd $(TEMP_REPO) && git fsck
+	rm -rf $(TEMP_REPO)
+
+test-coverage:
+	@echo "running against `git version`"; \
+	echo "" > $(COVERAGE_REPORT); \
+	$(GOTEST) -coverprofile=$(COVERAGE_REPORT) -coverpkg=./... -covermode=$(COVERAGE_MODE) ./...
+
+clean:
+	rm -rf $(GIT_DIST_PATH)
+
+fuzz:
+	@go test -fuzz=FuzzParser				$(PWD)/internal/revision
+	@go test -fuzz=FuzzDecoder				$(PWD)/plumbing/format/config
+	@go test -fuzz=FuzzPatchDelta			$(PWD)/plumbing/format/packfile
+	@go test -fuzz=FuzzParseSignedBytes		$(PWD)/plumbing/object
+	@go test -fuzz=FuzzDecode				$(PWD)/plumbing/object
+	@go test -fuzz=FuzzDecoder				$(PWD)/plumbing/protocol/packp
+	@go test -fuzz=FuzzNewEndpoint			$(PWD)/plumbing/transport

vendor/github.com/go-git/go-git/v5/README.md

@@ -0,0 +1,131 @@
+![go-git logo](https://cdn.rawgit.com/src-d/artwork/02036484/go-git/files/go-git-github-readme-header.png)
+[![GoDoc](https://godoc.org/github.com/go-git/go-git/v5?status.svg)](https://pkg.go.dev/github.com/go-git/go-git/v5) [![Build Status](https://github.com/go-git/go-git/workflows/Test/badge.svg)](https://github.com/go-git/go-git/actions) [![Go Report Card](https://goreportcard.com/badge/github.com/go-git/go-git)](https://goreportcard.com/report/github.com/go-git/go-git)
+
+*go-git* is a highly extensible git implementation library written in **pure Go**.
+
+It can be used to manipulate git repositories at low level *(plumbing)* or high level *(porcelain)*, through an idiomatic Go API. It also supports several types of storage, such as in-memory filesystems, or custom implementations, thanks to the [`Storer`](https://pkg.go.dev/github.com/go-git/go-git/v5/plumbing/storer) interface.
+
+It's being actively developed since 2015 and is being used extensively by [Keybase](https://keybase.io/blog/encrypted-git-for-everyone), [Gitea](https://gitea.io/en-us/) or [Pulumi](https://github.com/search?q=org%3Apulumi+go-git&type=Code), and by many other libraries and tools.
+
+Project Status
+--------------
+
+After the legal issues with the [`src-d`](https://github.com/src-d) organization, the lack of update for four months and the requirement to make a hard fork, the project is **now back to normality**.
+
+The project is currently actively maintained by individual contributors, including several of the original authors, but also backed by a new company, [gitsight](https://github.com/gitsight), where `go-git` is a critical component used at scale.
+
+
+Comparison with git
+-------------------
+
+*go-git* aims to be fully compatible with [git](https://github.com/git/git), all the *porcelain* operations are implemented to work exactly as *git* does.
+
+*git* is a humongous project with years of development by thousands of contributors, making it challenging for *go-git* to implement all the features. You can find a comparison of *go-git* vs *git* in the [compatibility documentation](COMPATIBILITY.md).
+
+
+Installation
+------------
+
+The recommended way to install *go-git* is:
+
+```go
+import "github.com/go-git/go-git/v5" // with go modules enabled (GO111MODULE=on or outside GOPATH)
+import "github.com/go-git/go-git" // with go modules disabled
+```
+
+
+Examples
+--------
+
+> Please note that the `CheckIfError` and `Info` functions  used in the examples are from the [examples package](https://github.com/go-git/go-git/blob/master/_examples/common.go#L19) just to be used in the examples.
+
+
+### Basic example
+
+A basic example that mimics the standard `git clone` command
+
+```go
+// Clone the given repository to the given directory
+Info("git clone https://github.com/go-git/go-git")
+
+_, err := git.PlainClone("/tmp/foo", false, &git.CloneOptions{
+    URL:      "https://github.com/go-git/go-git",
+    Progress: os.Stdout,
+})
+
+CheckIfError(err)
+```
+
+Outputs:
+```
+Counting objects: 4924, done.
+Compressing objects: 100% (1333/1333), done.
+Total 4924 (delta 530), reused 6 (delta 6), pack-reused 3533
+```
+
+### In-memory example
+
+Cloning a repository into memory and printing the history of HEAD, just like `git log` does
+
+
+```go
+// Clones the given repository in memory, creating the remote, the local
+// branches and fetching the objects, exactly as:
+Info("git clone https://github.com/go-git/go-billy")
+
+r, err := git.Clone(memory.NewStorage(), nil, &git.CloneOptions{
+    URL: "https://github.com/go-git/go-billy",
+})
+
+CheckIfError(err)
+
+// Gets the HEAD history from HEAD, just like this command:
+Info("git log")
+
+// ... retrieves the branch pointed by HEAD
+ref, err := r.Head()
+CheckIfError(err)
+
+
+// ... retrieves the commit history
+cIter, err := r.Log(&git.LogOptions{From: ref.Hash()})
+CheckIfError(err)
+
+// ... just iterates over the commits, printing it
+err = cIter.ForEach(func(c *object.Commit) error {
+	fmt.Println(c)
+	return nil
+})
+CheckIfError(err)
+```
+
+Outputs:
+```
+commit ded8054fd0c3994453e9c8aacaf48d118d42991e
+Author: Santiago M. Mola <santi@mola.io>
+Date:   Sat Nov 12 21:18:41 2016 +0100
+
+    index: ReadFrom/WriteTo returns IndexReadError/IndexWriteError. (#9)
+
+commit df707095626f384ce2dc1a83b30f9a21d69b9dfc
+Author: Santiago M. Mola <santi@mola.io>
+Date:   Fri Nov 11 13:23:22 2016 +0100
+
+    readwriter: fix bug when writing index. (#10)
+
+    When using ReadWriter on an existing siva file, absolute offset for
+    index entries was not being calculated correctly.
+...
+```
+
+You can find this [example](_examples/log/main.go) and many others in the [examples](_examples) folder.
+
+Contribute
+----------
+
+[Contributions](https://github.com/go-git/go-git/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) are more than welcome, if you are interested please take a look to
+our [Contributing Guidelines](CONTRIBUTING.md).
+
+License
+-------
+Apache License Version 2.0, see [LICENSE](LICENSE)

vendor/github.com/go-git/go-git/v5/SECURITY.md

@@ -0,0 +1,38 @@
+# go-git Security Policy
+
+The purpose of this security policy is to outline `go-git`'s process
+for reporting, handling and disclosing security sensitive information.
+
+## Supported Versions
+
+The project follows a version support policy where only the latest minor
+release is actively supported. Therefore, only issues that impact the latest
+minor release will be fixed. Users are encouraged to upgrade to the latest
+minor/patch release to benefit from the most up-to-date features, bug fixes,
+and security enhancements.​
+
+The supported versions policy applies to both the `go-git` library and its
+associated repositories within the `go-git` org.
+
+## Reporting Security Issues
+
+Please report any security vulnerabilities or potential weaknesses in `go-git`
+privately via go-git-security@googlegroups.com. Do not publicly disclose the
+details of the vulnerability until a fix has been implemented and released.
+
+During the process the project maintainers will investigate the report, so please
+provide detailed information, including steps to reproduce, affected versions, and any mitigations if known.
+
+The project maintainers will acknowledge the receipt of the report and work with
+the reporter to validate and address the issue.
+
+Please note that `go-git` does not have any bounty programs, and therefore do
+not provide financial compensation for disclosures.
+
+## Security Disclosure Process
+
+The project maintainers will make every effort to promptly address security issues.
+
+Once a security vulnerability is fixed, a security advisory will be published to notify users and provide appropriate mitigation measures.
+
+All `go-git` advisories can be found at https://github.com/go-git/go-git/security/advisories.

vendor/github.com/go-git/go-git/v5/blame.go

@@ -0,0 +1,590 @@
+package git
+
+import (
+	"bytes"
+	"container/heap"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+	"time"
+	"unicode/utf8"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/object"
+	"github.com/go-git/go-git/v5/utils/diff"
+	"github.com/sergi/go-diff/diffmatchpatch"
+)
+
+// BlameResult represents the result of a Blame operation.
+type BlameResult struct {
+	// Path is the path of the File that we're blaming.
+	Path string
+	// Rev (Revision) is the hash of the specified Commit used to generate this result.
+	Rev plumbing.Hash
+	// Lines contains every line with its authorship.
+	Lines []*Line
+}
+
+// Blame returns a BlameResult with the information about the last author of
+// each line from file `path` at commit `c`.
+func Blame(c *object.Commit, path string) (*BlameResult, error) {
+	// The file to blame is identified by the input arguments:
+	// commit and path. commit is a Commit object obtained from a Repository. Path
+	// represents a path to a specific file contained in the repository.
+	//
+	// Blaming a file is done by walking the tree in reverse order trying to find where each line was last modified.
+	//
+	// When a diff is found it cannot immediately assume it came from that commit, as it may have come from 1 of its
+	// parents, so it will first try to resolve those diffs from its parents, if it couldn't find the change in its
+	// parents then it will assign the change to itself.
+	//
+	// When encountering 2 parents that have made the same change to a file it will choose the parent that was merged
+	// into the current branch first (this is determined by the order of the parents inside the commit).
+	//
+	// This currently works on a line by line basis, if performance becomes an issue it could be changed to work with
+	// hunks rather than lines. Then when encountering diff hunks it would need to split them where necessary.
+
+	b := new(blame)
+	b.fRev = c
+	b.path = path
+	b.q = new(priorityQueue)
+
+	file, err := b.fRev.File(path)
+	if err != nil {
+		return nil, err
+	}
+	finalLines, err := file.Lines()
+	if err != nil {
+		return nil, err
+	}
+	finalLength := len(finalLines)
+
+	needsMap := make([]lineMap, finalLength)
+	for i := range needsMap {
+		needsMap[i] = lineMap{i, i, nil, -1}
+	}
+	contents, err := file.Contents()
+	if err != nil {
+		return nil, err
+	}
+	b.q.Push(&queueItem{
+		nil,
+		nil,
+		c,
+		path,
+		contents,
+		needsMap,
+		0,
+		false,
+		0,
+	})
+	items := make([]*queueItem, 0)
+	for {
+		items = items[:0]
+		for {
+			if b.q.Len() == 0 {
+				return nil, errors.New("invalid state: no items left on the blame queue")
+			}
+			item := b.q.Pop()
+			items = append(items, item)
+			next := b.q.Peek()
+			if next == nil || next.Hash != item.Commit.Hash {
+				break
+			}
+		}
+		finished, err := b.addBlames(items)
+		if err != nil {
+			return nil, err
+		}
+		if finished == true {
+			break
+		}
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	b.lineToCommit = make([]*object.Commit, finalLength)
+	for i := range needsMap {
+		b.lineToCommit[i] = needsMap[i].Commit
+	}
+
+	lines, err := newLines(finalLines, b.lineToCommit)
+	if err != nil {
+		return nil, err
+	}
+
+	return &BlameResult{
+		Path:  path,
+		Rev:   c.Hash,
+		Lines: lines,
+	}, nil
+}
+
+// Line values represent the contents and author of a line in BlamedResult values.
+type Line struct {
+	// Author is the email address of the last author that modified the line.
+	Author string
+	// AuthorName is the name of the last author that modified the line.
+	AuthorName string
+	// Text is the original text of the line.
+	Text string
+	// Date is when the original text of the line was introduced
+	Date time.Time
+	// Hash is the commit hash that introduced the original line
+	Hash plumbing.Hash
+}
+
+func newLine(author, authorName, text string, date time.Time, hash plumbing.Hash) *Line {
+	return &Line{
+		Author:     author,
+		AuthorName: authorName,
+		Text:       text,
+		Hash:       hash,
+		Date:       date,
+	}
+}
+
+func newLines(contents []string, commits []*object.Commit) ([]*Line, error) {
+	result := make([]*Line, 0, len(contents))
+	for i := range contents {
+		result = append(result, newLine(
+			commits[i].Author.Email, commits[i].Author.Name, contents[i],
+			commits[i].Author.When, commits[i].Hash,
+		))
+	}
+
+	return result, nil
+}
+
+// this struct is internally used by the blame function to hold its
+// inputs, outputs and state.
+type blame struct {
+	// the path of the file to blame
+	path string
+	// the commit of the final revision of the file to blame
+	fRev *object.Commit
+	// resolved lines
+	lineToCommit []*object.Commit
+	// queue of commits that need resolving
+	q *priorityQueue
+}
+
+type lineMap struct {
+	Orig, Cur    int
+	Commit       *object.Commit
+	FromParentNo int
+}
+
+func (b *blame) addBlames(curItems []*queueItem) (bool, error) {
+	curItem := curItems[0]
+
+	// Simple optimisation to merge paths, there is potential to go a bit further here and check for any duplicates
+	// not only if they are all the same.
+	if len(curItems) == 1 {
+		curItems = nil
+	} else if curItem.IdenticalToChild {
+		allSame := true
+		lenCurItems := len(curItems)
+		lowestParentNo := curItem.ParentNo
+		for i := 1; i < lenCurItems; i++ {
+			if !curItems[i].IdenticalToChild || curItem.Child != curItems[i].Child {
+				allSame = false
+				break
+			}
+			lowestParentNo = min(lowestParentNo, curItems[i].ParentNo)
+		}
+		if allSame {
+			curItem.Child.numParentsNeedResolving = curItem.Child.numParentsNeedResolving - lenCurItems + 1
+			curItems = nil // free the memory
+			curItem.ParentNo = lowestParentNo
+
+			// Now check if we can remove the parent completely
+			for curItem.Child.IdenticalToChild && curItem.Child.MergedChildren == nil && curItem.Child.numParentsNeedResolving == 1 {
+				oldChild := curItem.Child
+				curItem.Child = oldChild.Child
+				curItem.ParentNo = oldChild.ParentNo
+			}
+		}
+	}
+
+	// if we have more than 1 item for this commit, create a single needsMap
+	if len(curItems) > 1 {
+		curItem.MergedChildren = make([]childToNeedsMap, len(curItems))
+		for i, c := range curItems {
+			curItem.MergedChildren[i] = childToNeedsMap{c.Child, c.NeedsMap, c.IdenticalToChild, c.ParentNo}
+		}
+		newNeedsMap := make([]lineMap, 0, len(curItem.NeedsMap))
+		newNeedsMap = append(newNeedsMap, curItems[0].NeedsMap...)
+
+		for i := 1; i < len(curItems); i++ {
+			cur := curItems[i].NeedsMap
+			n := 0 // position in newNeedsMap
+			c := 0 // position in current list
+			for c < len(cur) {
+				if n == len(newNeedsMap) {
+					newNeedsMap = append(newNeedsMap, cur[c:]...)
+					break
+				} else if newNeedsMap[n].Cur == cur[c].Cur {
+					n++
+					c++
+				} else if newNeedsMap[n].Cur < cur[c].Cur {
+					n++
+				} else {
+					newNeedsMap = append(newNeedsMap, cur[c])
+					newPos := len(newNeedsMap) - 1
+					for newPos > n {
+						newNeedsMap[newPos-1], newNeedsMap[newPos] = newNeedsMap[newPos], newNeedsMap[newPos-1]
+						newPos--
+					}
+				}
+			}
+		}
+		curItem.NeedsMap = newNeedsMap
+		curItem.IdenticalToChild = false
+		curItem.Child = nil
+		curItems = nil // free the memory
+	}
+
+	parents, err := parentsContainingPath(curItem.path, curItem.Commit)
+	if err != nil {
+		return false, err
+	}
+
+	anyPushed := false
+	for parnetNo, prev := range parents {
+		currentHash, err := blobHash(curItem.path, curItem.Commit)
+		if err != nil {
+			return false, err
+		}
+		prevHash, err := blobHash(prev.Path, prev.Commit)
+		if err != nil {
+			return false, err
+		}
+		if currentHash == prevHash {
+			if len(parents) == 1 && curItem.MergedChildren == nil && curItem.IdenticalToChild {
+				// commit that has 1 parent and 1 child and is the same as both, bypass it completely
+				b.q.Push(&queueItem{
+					Child:            curItem.Child,
+					Commit:           prev.Commit,
+					path:             prev.Path,
+					Contents:         curItem.Contents,
+					NeedsMap:         curItem.NeedsMap, // reuse the NeedsMap as we are throwing away this item
+					IdenticalToChild: true,
+					ParentNo:         curItem.ParentNo,
+				})
+			} else {
+				b.q.Push(&queueItem{
+					Child:            curItem,
+					Commit:           prev.Commit,
+					path:             prev.Path,
+					Contents:         curItem.Contents,
+					NeedsMap:         append([]lineMap(nil), curItem.NeedsMap...), // create new slice and copy
+					IdenticalToChild: true,
+					ParentNo:         parnetNo,
+				})
+				curItem.numParentsNeedResolving++
+			}
+			anyPushed = true
+			continue
+		}
+
+		// get the contents of the file
+		file, err := prev.Commit.File(prev.Path)
+		if err != nil {
+			return false, err
+		}
+		prevContents, err := file.Contents()
+		if err != nil {
+			return false, err
+		}
+
+		hunks := diff.Do(prevContents, curItem.Contents)
+		prevl := -1
+		curl := -1
+		need := 0
+		getFromParent := make([]lineMap, 0)
+	out:
+		for h := range hunks {
+			hLines := countLines(hunks[h].Text)
+			for hl := 0; hl < hLines; hl++ {
+				switch {
+				case hunks[h].Type == diffmatchpatch.DiffEqual:
+					prevl++
+					curl++
+					if curl == curItem.NeedsMap[need].Cur {
+						// add to needs
+						getFromParent = append(getFromParent, lineMap{curl, prevl, nil, -1})
+						// move to next need
+						need++
+						if need >= len(curItem.NeedsMap) {
+							break out
+						}
+					}
+				case hunks[h].Type == diffmatchpatch.DiffInsert:
+					curl++
+					if curl == curItem.NeedsMap[need].Cur {
+						// the line we want is added, it may have been added here (or by another parent), skip it for now
+						need++
+						if need >= len(curItem.NeedsMap) {
+							break out
+						}
+					}
+				case hunks[h].Type == diffmatchpatch.DiffDelete:
+					prevl += hLines
+					continue out
+				default:
+					return false, errors.New("invalid state: invalid hunk Type")
+				}
+			}
+		}
+
+		if len(getFromParent) > 0 {
+			b.q.Push(&queueItem{
+				curItem,
+				nil,
+				prev.Commit,
+				prev.Path,
+				prevContents,
+				getFromParent,
+				0,
+				false,
+				parnetNo,
+			})
+			curItem.numParentsNeedResolving++
+			anyPushed = true
+		}
+	}
+
+	curItem.Contents = "" // no longer need, free the memory
+
+	if !anyPushed {
+		return finishNeeds(curItem)
+	}
+
+	return false, nil
+}
+
+func finishNeeds(curItem *queueItem) (bool, error) {
+	// any needs left in the needsMap must have come from this revision
+	for i := range curItem.NeedsMap {
+		if curItem.NeedsMap[i].Commit == nil {
+			curItem.NeedsMap[i].Commit = curItem.Commit
+			curItem.NeedsMap[i].FromParentNo = -1
+		}
+	}
+
+	if curItem.Child == nil && curItem.MergedChildren == nil {
+		return true, nil
+	}
+
+	if curItem.MergedChildren == nil {
+		return applyNeeds(curItem.Child, curItem.NeedsMap, curItem.IdenticalToChild, curItem.ParentNo)
+	}
+
+	for _, ctn := range curItem.MergedChildren {
+		m := 0 // position in merged needs map
+		p := 0 // position in parent needs map
+		for p < len(ctn.NeedsMap) {
+			if ctn.NeedsMap[p].Cur == curItem.NeedsMap[m].Cur {
+				ctn.NeedsMap[p].Commit = curItem.NeedsMap[m].Commit
+				m++
+				p++
+			} else if ctn.NeedsMap[p].Cur < curItem.NeedsMap[m].Cur {
+				p++
+			} else {
+				m++
+			}
+		}
+		finished, err := applyNeeds(ctn.Child, ctn.NeedsMap, ctn.IdenticalToChild, ctn.ParentNo)
+		if finished || err != nil {
+			return finished, err
+		}
+	}
+
+	return false, nil
+}
+
+func applyNeeds(child *queueItem, needsMap []lineMap, identicalToChild bool, parentNo int) (bool, error) {
+	if identicalToChild {
+		for i := range child.NeedsMap {
+			l := &child.NeedsMap[i]
+			if l.Cur != needsMap[i].Cur || l.Orig != needsMap[i].Orig {
+				return false, errors.New("needsMap isn't the same? Why not??")
+			}
+			if l.Commit == nil || parentNo < l.FromParentNo {
+				l.Commit = needsMap[i].Commit
+				l.FromParentNo = parentNo
+			}
+		}
+	} else {
+		i := 0
+	out:
+		for j := range child.NeedsMap {
+			l := &child.NeedsMap[j]
+			for needsMap[i].Orig < l.Cur {
+				i++
+				if i == len(needsMap) {
+					break out
+				}
+			}
+			if l.Cur == needsMap[i].Orig {
+				if l.Commit == nil || parentNo < l.FromParentNo {
+					l.Commit = needsMap[i].Commit
+					l.FromParentNo = parentNo
+				}
+			}
+		}
+	}
+	child.numParentsNeedResolving--
+	if child.numParentsNeedResolving == 0 {
+		finished, err := finishNeeds(child)
+		if finished || err != nil {
+			return finished, err
+		}
+	}
+
+	return false, nil
+}
+
+// String prints the results of a Blame using git-blame's style.
+func (b BlameResult) String() string {
+	var buf bytes.Buffer
+
+	// max line number length
+	mlnl := len(strconv.Itoa(len(b.Lines)))
+	// max author length
+	mal := b.maxAuthorLength()
+	format := fmt.Sprintf("%%s (%%-%ds %%s %%%dd) %%s\n", mal, mlnl)
+
+	for ln := range b.Lines {
+		_, _ = fmt.Fprintf(&buf, format, b.Lines[ln].Hash.String()[:8],
+			b.Lines[ln].AuthorName, b.Lines[ln].Date.Format("2006-01-02 15:04:05 -0700"), ln+1, b.Lines[ln].Text)
+	}
+	return buf.String()
+}
+
+// utility function to calculate the number of runes needed
+// to print the longest author name in the blame of a file.
+func (b BlameResult) maxAuthorLength() int {
+	m := 0
+	for ln := range b.Lines {
+		m = max(m, utf8.RuneCountInString(b.Lines[ln].AuthorName))
+	}
+	return m
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
+type childToNeedsMap struct {
+	Child            *queueItem
+	NeedsMap         []lineMap
+	IdenticalToChild bool
+	ParentNo         int
+}
+
+type queueItem struct {
+	Child                   *queueItem
+	MergedChildren          []childToNeedsMap
+	Commit                  *object.Commit
+	path                    string
+	Contents                string
+	NeedsMap                []lineMap
+	numParentsNeedResolving int
+	IdenticalToChild        bool
+	ParentNo                int
+}
+
+type priorityQueueImp []*queueItem
+
+func (pq *priorityQueueImp) Len() int { return len(*pq) }
+func (pq *priorityQueueImp) Less(i, j int) bool {
+	return !(*pq)[i].Commit.Less((*pq)[j].Commit)
+}
+func (pq *priorityQueueImp) Swap(i, j int) { (*pq)[i], (*pq)[j] = (*pq)[j], (*pq)[i] }
+func (pq *priorityQueueImp) Push(x any)    { *pq = append(*pq, x.(*queueItem)) }
+func (pq *priorityQueueImp) Pop() any {
+	n := len(*pq)
+	ret := (*pq)[n-1]
+	(*pq)[n-1] = nil // ovoid memory leak
+	*pq = (*pq)[0 : n-1]
+
+	return ret
+}
+func (pq *priorityQueueImp) Peek() *object.Commit {
+	if len(*pq) == 0 {
+		return nil
+	}
+	return (*pq)[0].Commit
+}
+
+type priorityQueue priorityQueueImp
+
+func (pq *priorityQueue) Init()    { heap.Init((*priorityQueueImp)(pq)) }
+func (pq *priorityQueue) Len() int { return (*priorityQueueImp)(pq).Len() }
+func (pq *priorityQueue) Push(c *queueItem) {
+	heap.Push((*priorityQueueImp)(pq), c)
+}
+func (pq *priorityQueue) Pop() *queueItem {
+	return heap.Pop((*priorityQueueImp)(pq)).(*queueItem)
+}
+func (pq *priorityQueue) Peek() *object.Commit { return (*priorityQueueImp)(pq).Peek() }
+
+type parentCommit struct {
+	Commit *object.Commit
+	Path   string
+}
+
+func parentsContainingPath(path string, c *object.Commit) ([]parentCommit, error) {
+	// TODO: benchmark this method making git.object.Commit.parent public instead of using
+	// an iterator
+	var result []parentCommit
+	iter := c.Parents()
+	for {
+		parent, err := iter.Next()
+		if err == io.EOF {
+			return result, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		if _, err := parent.File(path); err == nil {
+			result = append(result, parentCommit{parent, path})
+		} else {
+			// look for renames
+			patch, err := parent.Patch(c)
+			if err != nil {
+				return nil, err
+			} else if patch != nil {
+				for _, fp := range patch.FilePatches() {
+					from, to := fp.Files()
+					if from != nil && to != nil && to.Path() == path {
+						result = append(result, parentCommit{parent, from.Path()})
+						break
+					}
+				}
+			}
+		}
+	}
+}
+
+func blobHash(path string, commit *object.Commit) (plumbing.Hash, error) {
+	file, err := commit.File(path)
+	if err != nil {
+		return plumbing.ZeroHash, err
+	}
+	return file.Hash, nil
+}

vendor/github.com/go-git/go-git/v5/common.go

@@ -0,0 +1,20 @@
+package git
+
+import "strings"
+
+// countLines returns the number of lines in a string à la git, this is
+// The newline character is assumed to be '\n'.  The empty string
+// contains 0 lines.  If the last line of the string doesn't end with a
+// newline, it will still be considered a line.
+func countLines(s string) int {
+	if s == "" {
+		return 0
+	}
+
+	nEOL := strings.Count(s, "\n")
+	if strings.HasSuffix(s, "\n") {
+		return nEOL
+	}
+
+	return nEOL + 1
+}

vendor/github.com/go-git/go-git/v5/config/branch.go

@@ -0,0 +1,123 @@
+package config
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	format "github.com/go-git/go-git/v5/plumbing/format/config"
+)
+
+var (
+	errBranchEmptyName     = errors.New("branch config: empty name")
+	errBranchInvalidMerge  = errors.New("branch config: invalid merge")
+	errBranchInvalidRebase = errors.New("branch config: rebase must be one of 'true' or 'interactive'")
+)
+
+// Branch contains information on the
+// local branches and which remote to track
+type Branch struct {
+	// Name of branch
+	Name string
+	// Remote name of remote to track
+	Remote string
+	// Merge is the local refspec for the branch
+	Merge plumbing.ReferenceName
+	// Rebase instead of merge when pulling. Valid values are
+	// "true" and "interactive".  "false" is undocumented and
+	// typically represented by the non-existence of this field
+	Rebase string
+	// Description explains what the branch is for.
+	// Multi-line explanations may be used.
+	//
+	// Original git command to edit:
+	//	git branch --edit-description
+	Description string
+
+	raw *format.Subsection
+}
+
+// Validate validates fields of branch
+func (b *Branch) Validate() error {
+	if b.Name == "" {
+		return errBranchEmptyName
+	}
+
+	if b.Merge != "" && !b.Merge.IsBranch() {
+		return errBranchInvalidMerge
+	}
+
+	if b.Rebase != "" &&
+		b.Rebase != "true" &&
+		b.Rebase != "interactive" &&
+		b.Rebase != "false" {
+		return errBranchInvalidRebase
+	}
+
+	return plumbing.NewBranchReferenceName(b.Name).Validate()
+}
+
+func (b *Branch) marshal() *format.Subsection {
+	if b.raw == nil {
+		b.raw = &format.Subsection{}
+	}
+
+	b.raw.Name = b.Name
+
+	if b.Remote == "" {
+		b.raw.RemoveOption(remoteSection)
+	} else {
+		b.raw.SetOption(remoteSection, b.Remote)
+	}
+
+	if b.Merge == "" {
+		b.raw.RemoveOption(mergeKey)
+	} else {
+		b.raw.SetOption(mergeKey, string(b.Merge))
+	}
+
+	if b.Rebase == "" {
+		b.raw.RemoveOption(rebaseKey)
+	} else {
+		b.raw.SetOption(rebaseKey, b.Rebase)
+	}
+
+	if b.Description == "" {
+		b.raw.RemoveOption(descriptionKey)
+	} else {
+		desc := quoteDescription(b.Description)
+		b.raw.SetOption(descriptionKey, desc)
+	}
+
+	return b.raw
+}
+
+// hack to trigger conditional quoting in the
+// plumbing/format/config/Encoder.encodeOptions
+//
+// Current Encoder implementation uses Go %q format if value contains a backslash character,
+// which is not consistent with reference git implementation.
+// git just replaces newline characters with \n, while Encoder prints them directly.
+// Until value quoting fix, we should escape description value by replacing newline characters with \n.
+func quoteDescription(desc string) string {
+	return strings.ReplaceAll(desc, "\n", `\n`)
+}
+
+func (b *Branch) unmarshal(s *format.Subsection) error {
+	b.raw = s
+
+	b.Name = b.raw.Name
+	b.Remote = b.raw.Options.Get(remoteSection)
+	b.Merge = plumbing.ReferenceName(b.raw.Options.Get(mergeKey))
+	b.Rebase = b.raw.Options.Get(rebaseKey)
+	b.Description = unquoteDescription(b.raw.Options.Get(descriptionKey))
+
+	return b.Validate()
+}
+
+// hack to enable conditional quoting in the
+// plumbing/format/config/Encoder.encodeOptions
+// goto quoteDescription for details.
+func unquoteDescription(desc string) string {
+	return strings.ReplaceAll(desc, `\n`, "\n")
+}

vendor/github.com/go-git/go-git/v5/config/config.go

@@ -0,0 +1,696 @@
+// Package config contains the abstraction of multiple config files
+package config
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strconv"
+
+	"github.com/go-git/go-billy/v5/osfs"
+	"github.com/go-git/go-git/v5/internal/url"
+	"github.com/go-git/go-git/v5/plumbing"
+	format "github.com/go-git/go-git/v5/plumbing/format/config"
+)
+
+const (
+	// DefaultFetchRefSpec is the default refspec used for fetch.
+	DefaultFetchRefSpec = "+refs/heads/*:refs/remotes/%s/*"
+	// DefaultPushRefSpec is the default refspec used for push.
+	DefaultPushRefSpec = "refs/heads/*:refs/heads/*"
+)
+
+// ConfigStorer generic storage of Config object
+type ConfigStorer interface {
+	Config() (*Config, error)
+	SetConfig(*Config) error
+}
+
+var (
+	ErrInvalid               = errors.New("config invalid key in remote or branch")
+	ErrRemoteConfigNotFound  = errors.New("remote config not found")
+	ErrRemoteConfigEmptyURL  = errors.New("remote config: empty URL")
+	ErrRemoteConfigEmptyName = errors.New("remote config: empty name")
+)
+
+// Scope defines the scope of a config file, such as local, global or system.
+type Scope int
+
+// Available ConfigScope's
+const (
+	LocalScope Scope = iota
+	GlobalScope
+	SystemScope
+)
+
+// Config contains the repository configuration
+// https://www.kernel.org/pub/software/scm/git/docs/git-config.html#FILES
+type Config struct {
+	Core struct {
+		// IsBare if true this repository is assumed to be bare and has no
+		// working directory associated with it.
+		IsBare bool
+		// Worktree is the path to the root of the working tree.
+		Worktree string
+		// CommentChar is the character indicating the start of a
+		// comment for commands like commit and tag
+		CommentChar string
+		// RepositoryFormatVersion identifies the repository format and layout version.
+		RepositoryFormatVersion format.RepositoryFormatVersion
+	}
+
+	User struct {
+		// Name is the personal name of the author and the committer of a commit.
+		Name string
+		// Email is the email of the author and the committer of a commit.
+		Email string
+	}
+
+	Author struct {
+		// Name is the personal name of the author of a commit.
+		Name string
+		// Email is the email of the author of a commit.
+		Email string
+	}
+
+	Committer struct {
+		// Name is the personal name of the committer of a commit.
+		Name string
+		// Email is the email of the committer of a commit.
+		Email string
+	}
+
+	Pack struct {
+		// Window controls the size of the sliding window for delta
+		// compression.  The default is 10.  A value of 0 turns off
+		// delta compression entirely.
+		Window uint
+	}
+
+	Init struct {
+		// DefaultBranch Allows overriding the default branch name
+		// e.g. when initializing a new repository or when cloning
+		// an empty repository.
+		DefaultBranch string
+	}
+
+	Extensions struct {
+		// ObjectFormat specifies the hash algorithm to use. The
+		// acceptable values are sha1 and sha256. If not specified,
+		// sha1 is assumed. It is an error to specify this key unless
+		// core.repositoryFormatVersion is 1.
+		//
+		// This setting must not be changed after repository initialization
+		// (e.g. clone or init).
+		ObjectFormat format.ObjectFormat
+	}
+
+	// Remotes list of repository remotes, the key of the map is the name
+	// of the remote, should equal to RemoteConfig.Name.
+	Remotes map[string]*RemoteConfig
+	// Submodules list of repository submodules, the key of the map is the name
+	// of the submodule, should equal to Submodule.Name.
+	Submodules map[string]*Submodule
+	// Branches list of branches, the key is the branch name and should
+	// equal Branch.Name
+	Branches map[string]*Branch
+	// URLs list of url rewrite rules, if repo url starts with URL.InsteadOf value, it will be replaced with the
+	// key instead.
+	URLs map[string]*URL
+	// Raw contains the raw information of a config file. The main goal is
+	// preserve the parsed information from the original format, to avoid
+	// dropping unsupported fields.
+	Raw *format.Config
+}
+
+// NewConfig returns a new empty Config.
+func NewConfig() *Config {
+	config := &Config{
+		Remotes:    make(map[string]*RemoteConfig),
+		Submodules: make(map[string]*Submodule),
+		Branches:   make(map[string]*Branch),
+		URLs:       make(map[string]*URL),
+		Raw:        format.New(),
+	}
+
+	config.Pack.Window = DefaultPackWindow
+
+	return config
+}
+
+// ReadConfig reads a config file from a io.Reader.
+func ReadConfig(r io.Reader) (*Config, error) {
+	b, err := io.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+
+	cfg := NewConfig()
+	if err = cfg.Unmarshal(b); err != nil {
+		return nil, err
+	}
+
+	return cfg, nil
+}
+
+// LoadConfig loads a config file from a given scope. The returned Config,
+// contains exclusively information from the given scope. If it couldn't find a
+// config file to the given scope, an empty one is returned.
+func LoadConfig(scope Scope) (*Config, error) {
+	if scope == LocalScope {
+		return nil, fmt.Errorf("LocalScope should be read from the a ConfigStorer")
+	}
+
+	files, err := Paths(scope)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, file := range files {
+		f, err := osfs.Default.Open(file)
+		if err != nil {
+			if os.IsNotExist(err) {
+				continue
+			}
+
+			return nil, err
+		}
+
+		defer f.Close()
+		return ReadConfig(f)
+	}
+
+	return NewConfig(), nil
+}
+
+// Paths returns the config file location for a given scope.
+func Paths(scope Scope) ([]string, error) {
+	var files []string
+	switch scope {
+	case GlobalScope:
+		xdg := os.Getenv("XDG_CONFIG_HOME")
+		if xdg != "" {
+			files = append(files, filepath.Join(xdg, "git/config"))
+		}
+
+		home, err := os.UserHomeDir()
+		if err != nil {
+			return nil, err
+		}
+
+		files = append(files,
+			filepath.Join(home, ".gitconfig"),
+			filepath.Join(home, ".config/git/config"),
+		)
+	case SystemScope:
+		files = append(files, "/etc/gitconfig")
+	}
+
+	return files, nil
+}
+
+// Validate validates the fields and sets the default values.
+func (c *Config) Validate() error {
+	for name, r := range c.Remotes {
+		if r.Name != name {
+			return ErrInvalid
+		}
+
+		if err := r.Validate(); err != nil {
+			return err
+		}
+	}
+
+	for name, b := range c.Branches {
+		if b.Name != name {
+			return ErrInvalid
+		}
+
+		if err := b.Validate(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+const (
+	remoteSection              = "remote"
+	submoduleSection           = "submodule"
+	branchSection              = "branch"
+	coreSection                = "core"
+	packSection                = "pack"
+	userSection                = "user"
+	authorSection              = "author"
+	committerSection           = "committer"
+	initSection                = "init"
+	urlSection                 = "url"
+	extensionsSection          = "extensions"
+	fetchKey                   = "fetch"
+	urlKey                     = "url"
+	bareKey                    = "bare"
+	worktreeKey                = "worktree"
+	commentCharKey             = "commentChar"
+	windowKey                  = "window"
+	mergeKey                   = "merge"
+	rebaseKey                  = "rebase"
+	nameKey                    = "name"
+	emailKey                   = "email"
+	descriptionKey             = "description"
+	defaultBranchKey           = "defaultBranch"
+	repositoryFormatVersionKey = "repositoryformatversion"
+	objectFormat               = "objectformat"
+	mirrorKey                  = "mirror"
+
+	// DefaultPackWindow holds the number of previous objects used to
+	// generate deltas. The value 10 is the same used by git command.
+	DefaultPackWindow = uint(10)
+)
+
+// Unmarshal parses a git-config file and stores it.
+func (c *Config) Unmarshal(b []byte) error {
+	r := bytes.NewBuffer(b)
+	d := format.NewDecoder(r)
+
+	c.Raw = format.New()
+	if err := d.Decode(c.Raw); err != nil {
+		return err
+	}
+
+	c.unmarshalCore()
+	c.unmarshalUser()
+	c.unmarshalInit()
+	if err := c.unmarshalPack(); err != nil {
+		return err
+	}
+	unmarshalSubmodules(c.Raw, c.Submodules)
+
+	if err := c.unmarshalBranches(); err != nil {
+		return err
+	}
+
+	if err := c.unmarshalURLs(); err != nil {
+		return err
+	}
+
+	return c.unmarshalRemotes()
+}
+
+func (c *Config) unmarshalCore() {
+	s := c.Raw.Section(coreSection)
+	if s.Options.Get(bareKey) == "true" {
+		c.Core.IsBare = true
+	}
+
+	c.Core.Worktree = s.Options.Get(worktreeKey)
+	c.Core.CommentChar = s.Options.Get(commentCharKey)
+}
+
+func (c *Config) unmarshalUser() {
+	s := c.Raw.Section(userSection)
+	c.User.Name = s.Options.Get(nameKey)
+	c.User.Email = s.Options.Get(emailKey)
+
+	s = c.Raw.Section(authorSection)
+	c.Author.Name = s.Options.Get(nameKey)
+	c.Author.Email = s.Options.Get(emailKey)
+
+	s = c.Raw.Section(committerSection)
+	c.Committer.Name = s.Options.Get(nameKey)
+	c.Committer.Email = s.Options.Get(emailKey)
+}
+
+func (c *Config) unmarshalPack() error {
+	s := c.Raw.Section(packSection)
+	window := s.Options.Get(windowKey)
+	if window == "" {
+		c.Pack.Window = DefaultPackWindow
+	} else {
+		winUint, err := strconv.ParseUint(window, 10, 32)
+		if err != nil {
+			return err
+		}
+		c.Pack.Window = uint(winUint)
+	}
+	return nil
+}
+
+func (c *Config) unmarshalRemotes() error {
+	s := c.Raw.Section(remoteSection)
+	for _, sub := range s.Subsections {
+		r := &RemoteConfig{}
+		if err := r.unmarshal(sub); err != nil {
+			return err
+		}
+
+		c.Remotes[r.Name] = r
+	}
+
+	// Apply insteadOf url rules
+	for _, r := range c.Remotes {
+		r.applyURLRules(c.URLs)
+	}
+
+	return nil
+}
+
+func (c *Config) unmarshalURLs() error {
+	s := c.Raw.Section(urlSection)
+	for _, sub := range s.Subsections {
+		r := &URL{}
+		if err := r.unmarshal(sub); err != nil {
+			return err
+		}
+
+		c.URLs[r.Name] = r
+	}
+
+	return nil
+}
+
+func unmarshalSubmodules(fc *format.Config, submodules map[string]*Submodule) {
+	s := fc.Section(submoduleSection)
+	for _, sub := range s.Subsections {
+		m := &Submodule{}
+		m.unmarshal(sub)
+
+		if m.Validate() == ErrModuleBadPath {
+			continue
+		}
+
+		submodules[m.Name] = m
+	}
+}
+
+func (c *Config) unmarshalBranches() error {
+	bs := c.Raw.Section(branchSection)
+	for _, sub := range bs.Subsections {
+		b := &Branch{}
+
+		if err := b.unmarshal(sub); err != nil {
+			return err
+		}
+
+		c.Branches[b.Name] = b
+	}
+	return nil
+}
+
+func (c *Config) unmarshalInit() {
+	s := c.Raw.Section(initSection)
+	c.Init.DefaultBranch = s.Options.Get(defaultBranchKey)
+}
+
+// Marshal returns Config encoded as a git-config file.
+func (c *Config) Marshal() ([]byte, error) {
+	c.marshalCore()
+	c.marshalExtensions()
+	c.marshalUser()
+	c.marshalPack()
+	c.marshalRemotes()
+	c.marshalSubmodules()
+	c.marshalBranches()
+	c.marshalURLs()
+	c.marshalInit()
+
+	buf := bytes.NewBuffer(nil)
+	if err := format.NewEncoder(buf).Encode(c.Raw); err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+func (c *Config) marshalCore() {
+	s := c.Raw.Section(coreSection)
+	s.SetOption(bareKey, fmt.Sprintf("%t", c.Core.IsBare))
+	if string(c.Core.RepositoryFormatVersion) != "" {
+		s.SetOption(repositoryFormatVersionKey, string(c.Core.RepositoryFormatVersion))
+	}
+
+	if c.Core.Worktree != "" {
+		s.SetOption(worktreeKey, c.Core.Worktree)
+	}
+}
+
+func (c *Config) marshalExtensions() {
+	// Extensions are only supported on Version 1, therefore
+	// ignore them otherwise.
+	if c.Core.RepositoryFormatVersion == format.Version_1 {
+		s := c.Raw.Section(extensionsSection)
+		s.SetOption(objectFormat, string(c.Extensions.ObjectFormat))
+	}
+}
+
+func (c *Config) marshalUser() {
+	s := c.Raw.Section(userSection)
+	if c.User.Name != "" {
+		s.SetOption(nameKey, c.User.Name)
+	}
+
+	if c.User.Email != "" {
+		s.SetOption(emailKey, c.User.Email)
+	}
+
+	s = c.Raw.Section(authorSection)
+	if c.Author.Name != "" {
+		s.SetOption(nameKey, c.Author.Name)
+	}
+
+	if c.Author.Email != "" {
+		s.SetOption(emailKey, c.Author.Email)
+	}
+
+	s = c.Raw.Section(committerSection)
+	if c.Committer.Name != "" {
+		s.SetOption(nameKey, c.Committer.Name)
+	}
+
+	if c.Committer.Email != "" {
+		s.SetOption(emailKey, c.Committer.Email)
+	}
+}
+
+func (c *Config) marshalPack() {
+	s := c.Raw.Section(packSection)
+	if c.Pack.Window != DefaultPackWindow {
+		s.SetOption(windowKey, fmt.Sprintf("%d", c.Pack.Window))
+	}
+}
+
+func (c *Config) marshalRemotes() {
+	s := c.Raw.Section(remoteSection)
+	newSubsections := make(format.Subsections, 0, len(c.Remotes))
+	added := make(map[string]bool)
+	for _, subsection := range s.Subsections {
+		if remote, ok := c.Remotes[subsection.Name]; ok {
+			newSubsections = append(newSubsections, remote.marshal())
+			added[subsection.Name] = true
+		}
+	}
+
+	remoteNames := make([]string, 0, len(c.Remotes))
+	for name := range c.Remotes {
+		remoteNames = append(remoteNames, name)
+	}
+
+	sort.Strings(remoteNames)
+
+	for _, name := range remoteNames {
+		if !added[name] {
+			newSubsections = append(newSubsections, c.Remotes[name].marshal())
+		}
+	}
+
+	s.Subsections = newSubsections
+}
+
+func (c *Config) marshalSubmodules() {
+	s := c.Raw.Section(submoduleSection)
+	s.Subsections = make(format.Subsections, len(c.Submodules))
+
+	var i int
+	for _, r := range c.Submodules {
+		section := r.marshal()
+		// the submodule section at config is a subset of the .gitmodule file
+		// we should remove the non-valid options for the config file.
+		section.RemoveOption(pathKey)
+		s.Subsections[i] = section
+		i++
+	}
+}
+
+func (c *Config) marshalBranches() {
+	s := c.Raw.Section(branchSection)
+	newSubsections := make(format.Subsections, 0, len(c.Branches))
+	added := make(map[string]bool)
+	for _, subsection := range s.Subsections {
+		if branch, ok := c.Branches[subsection.Name]; ok {
+			newSubsections = append(newSubsections, branch.marshal())
+			added[subsection.Name] = true
+		}
+	}
+
+	branchNames := make([]string, 0, len(c.Branches))
+	for name := range c.Branches {
+		branchNames = append(branchNames, name)
+	}
+
+	sort.Strings(branchNames)
+
+	for _, name := range branchNames {
+		if !added[name] {
+			newSubsections = append(newSubsections, c.Branches[name].marshal())
+		}
+	}
+
+	s.Subsections = newSubsections
+}
+
+func (c *Config) marshalURLs() {
+	s := c.Raw.Section(urlSection)
+	s.Subsections = make(format.Subsections, len(c.URLs))
+
+	var i int
+	for _, r := range c.URLs {
+		section := r.marshal()
+		// the submodule section at config is a subset of the .gitmodule file
+		// we should remove the non-valid options for the config file.
+		s.Subsections[i] = section
+		i++
+	}
+}
+
+func (c *Config) marshalInit() {
+	s := c.Raw.Section(initSection)
+	if c.Init.DefaultBranch != "" {
+		s.SetOption(defaultBranchKey, c.Init.DefaultBranch)
+	}
+}
+
+// RemoteConfig contains the configuration for a given remote repository.
+type RemoteConfig struct {
+	// Name of the remote
+	Name string
+	// URLs the URLs of a remote repository. It must be non-empty. Fetch will
+	// always use the first URL, while push will use all of them.
+	URLs []string
+	// Mirror indicates that the repository is a mirror of remote.
+	Mirror bool
+
+	// insteadOfRulesApplied have urls been modified
+	insteadOfRulesApplied bool
+	// originalURLs are the urls before applying insteadOf rules
+	originalURLs []string
+
+	// Fetch the default set of "refspec" for fetch operation
+	Fetch []RefSpec
+
+	// raw representation of the subsection, filled by marshal or unmarshal are
+	// called
+	raw *format.Subsection
+}
+
+// Validate validates the fields and sets the default values.
+func (c *RemoteConfig) Validate() error {
+	if c.Name == "" {
+		return ErrRemoteConfigEmptyName
+	}
+
+	if len(c.URLs) == 0 {
+		return ErrRemoteConfigEmptyURL
+	}
+
+	for _, r := range c.Fetch {
+		if err := r.Validate(); err != nil {
+			return err
+		}
+	}
+
+	if len(c.Fetch) == 0 {
+		c.Fetch = []RefSpec{RefSpec(fmt.Sprintf(DefaultFetchRefSpec, c.Name))}
+	}
+
+	return plumbing.NewRemoteHEADReferenceName(c.Name).Validate()
+}
+
+func (c *RemoteConfig) unmarshal(s *format.Subsection) error {
+	c.raw = s
+
+	fetch := []RefSpec{}
+	for _, f := range c.raw.Options.GetAll(fetchKey) {
+		rs := RefSpec(f)
+		if err := rs.Validate(); err != nil {
+			return err
+		}
+
+		fetch = append(fetch, rs)
+	}
+
+	c.Name = c.raw.Name
+	c.URLs = append([]string(nil), c.raw.Options.GetAll(urlKey)...)
+	c.Fetch = fetch
+	c.Mirror = c.raw.Options.Get(mirrorKey) == "true"
+
+	return nil
+}
+
+func (c *RemoteConfig) marshal() *format.Subsection {
+	if c.raw == nil {
+		c.raw = &format.Subsection{}
+	}
+
+	c.raw.Name = c.Name
+	if len(c.URLs) == 0 {
+		c.raw.RemoveOption(urlKey)
+	} else {
+		urls := c.URLs
+		if c.insteadOfRulesApplied {
+			urls = c.originalURLs
+		}
+
+		c.raw.SetOption(urlKey, urls...)
+	}
+
+	if len(c.Fetch) == 0 {
+		c.raw.RemoveOption(fetchKey)
+	} else {
+		var values []string
+		for _, rs := range c.Fetch {
+			values = append(values, rs.String())
+		}
+
+		c.raw.SetOption(fetchKey, values...)
+	}
+
+	if c.Mirror {
+		c.raw.SetOption(mirrorKey, strconv.FormatBool(c.Mirror))
+	}
+
+	return c.raw
+}
+
+func (c *RemoteConfig) IsFirstURLLocal() bool {
+	return url.IsLocalEndpoint(c.URLs[0])
+}
+
+func (c *RemoteConfig) applyURLRules(urlRules map[string]*URL) {
+	// save original urls
+	originalURLs := make([]string, len(c.URLs))
+	copy(originalURLs, c.URLs)
+
+	for i, url := range c.URLs {
+		if matchingURLRule := findLongestInsteadOfMatch(url, urlRules); matchingURLRule != nil {
+			c.URLs[i] = matchingURLRule.ApplyInsteadOf(c.URLs[i])
+			c.insteadOfRulesApplied = true
+		}
+	}
+
+	if c.insteadOfRulesApplied {
+		c.originalURLs = originalURLs
+	}
+}

vendor/github.com/go-git/go-git/v5/config/modules.go

@@ -0,0 +1,139 @@
+package config
+
+import (
+	"bytes"
+	"errors"
+	"regexp"
+
+	format "github.com/go-git/go-git/v5/plumbing/format/config"
+)
+
+var (
+	ErrModuleEmptyURL  = errors.New("module config: empty URL")
+	ErrModuleEmptyPath = errors.New("module config: empty path")
+	ErrModuleBadPath   = errors.New("submodule has an invalid path")
+)
+
+var (
+	// Matches module paths with dotdot ".." components.
+	dotdotPath = regexp.MustCompile(`(^|[/\\])\.\.([/\\]|$)`)
+)
+
+// Modules defines the submodules properties, represents a .gitmodules file
+// https://www.kernel.org/pub/software/scm/git/docs/gitmodules.html
+type Modules struct {
+	// Submodules is a map of submodules being the key the name of the submodule.
+	Submodules map[string]*Submodule
+
+	raw *format.Config
+}
+
+// NewModules returns a new empty Modules
+func NewModules() *Modules {
+	return &Modules{
+		Submodules: make(map[string]*Submodule),
+		raw:        format.New(),
+	}
+}
+
+const (
+	pathKey   = "path"
+	branchKey = "branch"
+)
+
+// Unmarshal parses a git-config file and stores it.
+func (m *Modules) Unmarshal(b []byte) error {
+	r := bytes.NewBuffer(b)
+	d := format.NewDecoder(r)
+
+	m.raw = format.New()
+	if err := d.Decode(m.raw); err != nil {
+		return err
+	}
+
+	unmarshalSubmodules(m.raw, m.Submodules)
+	return nil
+}
+
+// Marshal returns Modules encoded as a git-config file.
+func (m *Modules) Marshal() ([]byte, error) {
+	s := m.raw.Section(submoduleSection)
+	s.Subsections = make(format.Subsections, len(m.Submodules))
+
+	var i int
+	for _, r := range m.Submodules {
+		s.Subsections[i] = r.marshal()
+		i++
+	}
+
+	buf := bytes.NewBuffer(nil)
+	if err := format.NewEncoder(buf).Encode(m.raw); err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+// Submodule defines a submodule.
+type Submodule struct {
+	// Name module name
+	Name string
+	// Path defines the path, relative to the top-level directory of the Git
+	// working tree.
+	Path string
+	// URL defines a URL from which the submodule repository can be cloned.
+	URL string
+	// Branch is a remote branch name for tracking updates in the upstream
+	// submodule. Optional value.
+	Branch string
+
+	// raw representation of the subsection, filled by marshal or unmarshal are
+	// called.
+	raw *format.Subsection
+}
+
+// Validate validates the fields and sets the default values.
+func (m *Submodule) Validate() error {
+	if m.Path == "" {
+		return ErrModuleEmptyPath
+	}
+
+	if m.URL == "" {
+		return ErrModuleEmptyURL
+	}
+
+	if dotdotPath.MatchString(m.Path) {
+		return ErrModuleBadPath
+	}
+
+	return nil
+}
+
+func (m *Submodule) unmarshal(s *format.Subsection) {
+	m.raw = s
+
+	m.Name = m.raw.Name
+	m.Path = m.raw.Option(pathKey)
+	m.URL = m.raw.Option(urlKey)
+	m.Branch = m.raw.Option(branchKey)
+}
+
+func (m *Submodule) marshal() *format.Subsection {
+	if m.raw == nil {
+		m.raw = &format.Subsection{}
+	}
+
+	m.raw.Name = m.Name
+	if m.raw.Name == "" {
+		m.raw.Name = m.Path
+	}
+
+	m.raw.SetOption(pathKey, m.Path)
+	m.raw.SetOption(urlKey, m.URL)
+
+	if m.Branch != "" {
+		m.raw.SetOption(branchKey, m.Branch)
+	}
+
+	return m.raw
+}

vendor/github.com/go-git/go-git/v5/config/refspec.go

@@ -0,0 +1,155 @@
+package config
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/go-git/go-git/v5/plumbing"
+)
+
+const (
+	refSpecWildcard  = "*"
+	refSpecForce     = "+"
+	refSpecSeparator = ":"
+)
+
+var (
+	ErrRefSpecMalformedSeparator = errors.New("malformed refspec, separators are wrong")
+	ErrRefSpecMalformedWildcard  = errors.New("malformed refspec, mismatched number of wildcards")
+)
+
+// RefSpec is a mapping from local branches to remote references.
+// The format of the refspec is an optional +, followed by <src>:<dst>, where
+// <src> is the pattern for references on the remote side and <dst> is where
+// those references will be written locally. The + tells Git to update the
+// reference even if it isn’t a fast-forward.
+// eg.: "+refs/heads/*:refs/remotes/origin/*"
+//
+// https://git-scm.com/book/en/v2/Git-Internals-The-Refspec
+type RefSpec string
+
+// Validate validates the RefSpec
+func (s RefSpec) Validate() error {
+	spec := string(s)
+	if strings.Count(spec, refSpecSeparator) != 1 {
+		return ErrRefSpecMalformedSeparator
+	}
+
+	sep := strings.Index(spec, refSpecSeparator)
+	if sep == len(spec)-1 {
+		return ErrRefSpecMalformedSeparator
+	}
+
+	ws := strings.Count(spec[0:sep], refSpecWildcard)
+	wd := strings.Count(spec[sep+1:], refSpecWildcard)
+	if ws == wd && ws < 2 && wd < 2 {
+		return nil
+	}
+
+	return ErrRefSpecMalformedWildcard
+}
+
+// IsForceUpdate returns if update is allowed in non fast-forward merges.
+func (s RefSpec) IsForceUpdate() bool {
+	return s[0] == refSpecForce[0]
+}
+
+// IsDelete returns true if the refspec indicates a delete (empty src).
+func (s RefSpec) IsDelete() bool {
+	return s[0] == refSpecSeparator[0]
+}
+
+// IsExactSHA1 returns true if the source is a SHA1 hash.
+func (s RefSpec) IsExactSHA1() bool {
+	return plumbing.IsHash(s.Src())
+}
+
+// Src returns the src side.
+func (s RefSpec) Src() string {
+	spec := string(s)
+
+	var start int
+	if s.IsForceUpdate() {
+		start = 1
+	} else {
+		start = 0
+	}
+
+	end := strings.Index(spec, refSpecSeparator)
+	return spec[start:end]
+}
+
+// Match match the given plumbing.ReferenceName against the source.
+func (s RefSpec) Match(n plumbing.ReferenceName) bool {
+	if !s.IsWildcard() {
+		return s.matchExact(n)
+	}
+
+	return s.matchGlob(n)
+}
+
+// IsWildcard returns true if the RefSpec contains a wildcard.
+func (s RefSpec) IsWildcard() bool {
+	return strings.Contains(string(s), refSpecWildcard)
+}
+
+func (s RefSpec) matchExact(n plumbing.ReferenceName) bool {
+	return s.Src() == n.String()
+}
+
+func (s RefSpec) matchGlob(n plumbing.ReferenceName) bool {
+	src := s.Src()
+	name := n.String()
+	wildcard := strings.Index(src, refSpecWildcard)
+
+	var prefix, suffix string
+	prefix = src[0:wildcard]
+	if len(src) > wildcard+1 {
+		suffix = src[wildcard+1:]
+	}
+
+	return len(name) >= len(prefix)+len(suffix) &&
+		strings.HasPrefix(name, prefix) &&
+		strings.HasSuffix(name, suffix)
+}
+
+// Dst returns the destination for the given remote reference.
+func (s RefSpec) Dst(n plumbing.ReferenceName) plumbing.ReferenceName {
+	spec := string(s)
+	start := strings.Index(spec, refSpecSeparator) + 1
+	dst := spec[start:]
+	src := s.Src()
+
+	if !s.IsWildcard() {
+		return plumbing.ReferenceName(dst)
+	}
+
+	name := n.String()
+	ws := strings.Index(src, refSpecWildcard)
+	wd := strings.Index(dst, refSpecWildcard)
+	match := name[ws : len(name)-(len(src)-(ws+1))]
+
+	return plumbing.ReferenceName(dst[0:wd] + match + dst[wd+1:])
+}
+
+func (s RefSpec) Reverse() RefSpec {
+	spec := string(s)
+	separator := strings.Index(spec, refSpecSeparator)
+
+	return RefSpec(spec[separator+1:] + refSpecSeparator + spec[:separator])
+}
+
+func (s RefSpec) String() string {
+	return string(s)
+}
+
+// MatchAny returns true if any of the RefSpec match with the given ReferenceName.
+func MatchAny(l []RefSpec, n plumbing.ReferenceName) bool {
+	for _, r := range l {
+		if r.Match(n) {
+			return true
+		}
+	}
+
+	return false
+}

vendor/github.com/go-git/go-git/v5/config/url.go

@@ -0,0 +1,81 @@
+package config
+
+import (
+	"errors"
+	"strings"
+
+	format "github.com/go-git/go-git/v5/plumbing/format/config"
+)
+
+var (
+	errURLEmptyInsteadOf = errors.New("url config: empty insteadOf")
+)
+
+// Url defines Url rewrite rules
+type URL struct {
+	// Name new base url
+	Name string
+	// Any URL that starts with this value will be rewritten to start, instead, with <base>.
+	// When more than one insteadOf strings match a given URL, the longest match is used.
+	InsteadOf string
+
+	// raw representation of the subsection, filled by marshal or unmarshal are
+	// called.
+	raw *format.Subsection
+}
+
+// Validate validates fields of branch
+func (b *URL) Validate() error {
+	if b.InsteadOf == "" {
+		return errURLEmptyInsteadOf
+	}
+
+	return nil
+}
+
+const (
+	insteadOfKey = "insteadOf"
+)
+
+func (u *URL) unmarshal(s *format.Subsection) error {
+	u.raw = s
+
+	u.Name = s.Name
+	u.InsteadOf = u.raw.Option(insteadOfKey)
+	return nil
+}
+
+func (u *URL) marshal() *format.Subsection {
+	if u.raw == nil {
+		u.raw = &format.Subsection{}
+	}
+
+	u.raw.Name = u.Name
+	u.raw.SetOption(insteadOfKey, u.InsteadOf)
+
+	return u.raw
+}
+
+func findLongestInsteadOfMatch(remoteURL string, urls map[string]*URL) *URL {
+	var longestMatch *URL
+	for _, u := range urls {
+		if !strings.HasPrefix(remoteURL, u.InsteadOf) {
+			continue
+		}
+
+		// according to spec if there is more than one match, take the logest
+		if longestMatch == nil || len(longestMatch.InsteadOf) < len(u.InsteadOf) {
+			longestMatch = u
+		}
+	}
+
+	return longestMatch
+}
+
+func (u *URL) ApplyInsteadOf(url string) string {
+	if !strings.HasPrefix(url, u.InsteadOf) {
+		return url
+	}
+
+	return u.Name + url[len(u.InsteadOf):]
+}

vendor/github.com/go-git/go-git/v5/doc.go

@@ -0,0 +1,10 @@
+// A highly extensible git implementation in pure Go.
+//
+// go-git aims to reach the completeness of libgit2 or jgit, nowadays covers the
+// majority of the plumbing read operations and some of the main write
+// operations, but lacks the main porcelain operations such as merges.
+//
+// It is highly extensible, we have been following the open/close principle in
+// its design to facilitate extensions, mainly focusing the efforts on the
+// persistence of the objects.
+package git

vendor/github.com/go-git/go-git/v5/internal/path_util/path_util.go

@@ -0,0 +1,29 @@
+package path_util
+
+import (
+	"os"
+	"os/user"
+	"strings"
+)
+
+func ReplaceTildeWithHome(path string) (string, error) {
+	if strings.HasPrefix(path, "~") {
+		firstSlash := strings.Index(path, "/")
+		if firstSlash == 1 {
+			home, err := os.UserHomeDir()
+			if err != nil {
+				return path, err
+			}
+			return strings.Replace(path, "~", home, 1), nil
+		} else if firstSlash > 1 {
+			username := path[1:firstSlash]
+			userAccount, err := user.Lookup(username)
+			if err != nil {
+				return path, err
+			}
+			return strings.Replace(path, path[:firstSlash], userAccount.HomeDir, 1), nil
+		}
+	}
+
+	return path, nil
+}

vendor/github.com/go-git/go-git/v5/internal/revision/parser.go

@@ -0,0 +1,626 @@
+// Package revision extracts git revision from string
+// More information about revision : https://www.kernel.org/pub/software/scm/git/docs/gitrevisions.html
+package revision
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"regexp"
+	"strconv"
+	"time"
+)
+
+// ErrInvalidRevision is emitted if string doesn't match valid revision
+type ErrInvalidRevision struct {
+	s string
+}
+
+func (e *ErrInvalidRevision) Error() string {
+	return "Revision invalid : " + e.s
+}
+
+// Revisioner represents a revision component.
+// A revision is made of multiple revision components
+// obtained after parsing a revision string,
+// for instance revision "master~" will be converted in
+// two revision components Ref and TildePath
+type Revisioner interface {
+}
+
+// Ref represents a reference name : HEAD, master, <hash>
+type Ref string
+
+// TildePath represents ~, ~{n}
+type TildePath struct {
+	Depth int
+}
+
+// CaretPath represents ^, ^{n}
+type CaretPath struct {
+	Depth int
+}
+
+// CaretReg represents ^{/foo bar}
+type CaretReg struct {
+	Regexp *regexp.Regexp
+	Negate bool
+}
+
+// CaretType represents ^{commit}
+type CaretType struct {
+	ObjectType string
+}
+
+// AtReflog represents @{n}
+type AtReflog struct {
+	Depth int
+}
+
+// AtCheckout represents @{-n}
+type AtCheckout struct {
+	Depth int
+}
+
+// AtUpstream represents @{upstream}, @{u}
+type AtUpstream struct {
+	BranchName string
+}
+
+// AtPush represents @{push}
+type AtPush struct {
+	BranchName string
+}
+
+// AtDate represents @{"2006-01-02T15:04:05Z"}
+type AtDate struct {
+	Date time.Time
+}
+
+// ColonReg represents :/foo bar
+type ColonReg struct {
+	Regexp *regexp.Regexp
+	Negate bool
+}
+
+// ColonPath represents :./<path> :<path>
+type ColonPath struct {
+	Path string
+}
+
+// ColonStagePath represents :<n>:/<path>
+type ColonStagePath struct {
+	Path  string
+	Stage int
+}
+
+// Parser represents a parser
+// use to tokenize and transform to revisioner chunks
+// a given string
+type Parser struct {
+	s                 *scanner
+	currentParsedChar struct {
+		tok token
+		lit string
+	}
+	unreadLastChar bool
+}
+
+// NewParserFromString returns a new instance of parser from a string.
+func NewParserFromString(s string) *Parser {
+	return NewParser(bytes.NewBufferString(s))
+}
+
+// NewParser returns a new instance of parser.
+func NewParser(r io.Reader) *Parser {
+	return &Parser{s: newScanner(r)}
+}
+
+// scan returns the next token from the underlying scanner
+// or the last scanned token if an unscan was requested
+func (p *Parser) scan() (token, string, error) {
+	if p.unreadLastChar {
+		p.unreadLastChar = false
+		return p.currentParsedChar.tok, p.currentParsedChar.lit, nil
+	}
+
+	tok, lit, err := p.s.scan()
+
+	p.currentParsedChar.tok, p.currentParsedChar.lit = tok, lit
+
+	return tok, lit, err
+}
+
+// unscan pushes the previously read token back onto the buffer.
+func (p *Parser) unscan() { p.unreadLastChar = true }
+
+// Parse explode a revision string into revisioner chunks
+func (p *Parser) Parse() ([]Revisioner, error) {
+	var rev Revisioner
+	var revs []Revisioner
+	var tok token
+	var err error
+
+	for {
+		tok, _, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		switch tok {
+		case at:
+			rev, err = p.parseAt()
+		case tilde:
+			rev, err = p.parseTilde()
+		case caret:
+			rev, err = p.parseCaret()
+		case colon:
+			rev, err = p.parseColon()
+		case eof:
+			err = p.validateFullRevision(&revs)
+
+			if err != nil {
+				return []Revisioner{}, err
+			}
+
+			return revs, nil
+		default:
+			p.unscan()
+			rev, err = p.parseRef()
+		}
+
+		if err != nil {
+			return []Revisioner{}, err
+		}
+
+		revs = append(revs, rev)
+	}
+}
+
+// validateFullRevision ensures all revisioner chunks make a valid revision
+func (p *Parser) validateFullRevision(chunks *[]Revisioner) error {
+	var hasReference bool
+
+	for i, chunk := range *chunks {
+		switch chunk.(type) {
+		case Ref:
+			if i == 0 {
+				hasReference = true
+			} else {
+				return &ErrInvalidRevision{`reference must be defined once at the beginning`}
+			}
+		case AtDate:
+			if len(*chunks) == 1 || hasReference && len(*chunks) == 2 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`"@" statement is not valid, could be : <refname>@{<ISO-8601 date>}, @{<ISO-8601 date>}`}
+		case AtReflog:
+			if len(*chunks) == 1 || hasReference && len(*chunks) == 2 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`"@" statement is not valid, could be : <refname>@{<n>}, @{<n>}`}
+		case AtCheckout:
+			if len(*chunks) == 1 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`"@" statement is not valid, could be : @{-<n>}`}
+		case AtUpstream:
+			if len(*chunks) == 1 || hasReference && len(*chunks) == 2 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`"@" statement is not valid, could be : <refname>@{upstream}, @{upstream}, <refname>@{u}, @{u}`}
+		case AtPush:
+			if len(*chunks) == 1 || hasReference && len(*chunks) == 2 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`"@" statement is not valid, could be : <refname>@{push}, @{push}`}
+		case TildePath, CaretPath, CaretReg:
+			if !hasReference {
+				return &ErrInvalidRevision{`"~" or "^" statement must have a reference defined at the beginning`}
+			}
+		case ColonReg:
+			if len(*chunks) == 1 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`":" statement is not valid, could be : :/<regexp>`}
+		case ColonPath:
+			if i == len(*chunks)-1 && hasReference || len(*chunks) == 1 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`":" statement is not valid, could be : <revision>:<path>`}
+		case ColonStagePath:
+			if len(*chunks) == 1 {
+				return nil
+			}
+
+			return &ErrInvalidRevision{`":" statement is not valid, could be : :<n>:<path>`}
+		}
+	}
+
+	return nil
+}
+
+// parseAt extract @ statements
+func (p *Parser) parseAt() (Revisioner, error) {
+	var tok, nextTok token
+	var lit, nextLit string
+	var err error
+
+	tok, _, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	if tok != obrace {
+		p.unscan()
+
+		return Ref("HEAD"), nil
+	}
+
+	tok, lit, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	nextTok, nextLit, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	switch {
+	case tok == word && (lit == "u" || lit == "upstream") && nextTok == cbrace:
+		return AtUpstream{}, nil
+	case tok == word && lit == "push" && nextTok == cbrace:
+		return AtPush{}, nil
+	case tok == number && nextTok == cbrace:
+		n, _ := strconv.Atoi(lit)
+
+		return AtReflog{n}, nil
+	case tok == minus && nextTok == number:
+		n, _ := strconv.Atoi(nextLit)
+
+		t, _, err := p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		if t != cbrace {
+			return nil, &ErrInvalidRevision{s: `missing "}" in @{-n} structure`}
+		}
+
+		return AtCheckout{n}, nil
+	default:
+		p.unscan()
+
+		date := lit
+
+		for {
+			tok, lit, err = p.scan()
+
+			if err != nil {
+				return nil, err
+			}
+
+			switch {
+			case tok == cbrace:
+				t, err := time.Parse("2006-01-02T15:04:05Z", date)
+
+				if err != nil {
+					return nil, &ErrInvalidRevision{fmt.Sprintf(`wrong date "%s" must fit ISO-8601 format : 2006-01-02T15:04:05Z`, date)}
+				}
+
+				return AtDate{t}, nil
+			case tok == eof:
+				return nil, &ErrInvalidRevision{s: `missing "}" in @{<data>} structure`}
+			default:
+				date += lit
+			}
+		}
+	}
+}
+
+// parseTilde extract ~ statements
+func (p *Parser) parseTilde() (Revisioner, error) {
+	var tok token
+	var lit string
+	var err error
+
+	tok, lit, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	switch {
+	case tok == number:
+		n, _ := strconv.Atoi(lit)
+
+		return TildePath{n}, nil
+	default:
+		p.unscan()
+		return TildePath{1}, nil
+	}
+}
+
+// parseCaret extract ^ statements
+func (p *Parser) parseCaret() (Revisioner, error) {
+	var tok token
+	var lit string
+	var err error
+
+	tok, lit, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	switch {
+	case tok == obrace:
+		r, err := p.parseCaretBraces()
+
+		if err != nil {
+			return nil, err
+		}
+
+		return r, nil
+	case tok == number:
+		n, _ := strconv.Atoi(lit)
+
+		if n > 2 {
+			return nil, &ErrInvalidRevision{fmt.Sprintf(`"%s" found must be 0, 1 or 2 after "^"`, lit)}
+		}
+
+		return CaretPath{n}, nil
+	default:
+		p.unscan()
+		return CaretPath{1}, nil
+	}
+}
+
+// parseCaretBraces extract ^{<data>} statements
+func (p *Parser) parseCaretBraces() (Revisioner, error) {
+	var tok, nextTok token
+	var lit, _ string
+	start := true
+	var re string
+	var negate bool
+	var err error
+
+	for {
+		tok, lit, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		nextTok, _, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		switch {
+		case tok == word && nextTok == cbrace && (lit == "commit" || lit == "tree" || lit == "blob" || lit == "tag" || lit == "object"):
+			return CaretType{lit}, nil
+		case re == "" && tok == cbrace:
+			return CaretType{"tag"}, nil
+		case re == "" && tok == emark && nextTok == emark:
+			re += lit
+		case re == "" && tok == emark && nextTok == minus:
+			negate = true
+		case re == "" && tok == emark:
+			return nil, &ErrInvalidRevision{s: `revision suffix brace component sequences starting with "/!" others than those defined are reserved`}
+		case re == "" && tok == slash:
+			p.unscan()
+		case tok != slash && start:
+			return nil, &ErrInvalidRevision{fmt.Sprintf(`"%s" is not a valid revision suffix brace component`, lit)}
+		case tok == eof:
+			return nil, &ErrInvalidRevision{s: `missing "}" in ^{<data>} structure`}
+		case tok != cbrace:
+			p.unscan()
+			re += lit
+		case tok == cbrace:
+			p.unscan()
+
+			reg, err := regexp.Compile(re)
+
+			if err != nil {
+				return CaretReg{}, &ErrInvalidRevision{fmt.Sprintf(`revision suffix brace component, %s`, err.Error())}
+			}
+
+			return CaretReg{reg, negate}, nil
+		}
+
+		start = false
+	}
+}
+
+// parseColon extract : statements
+func (p *Parser) parseColon() (Revisioner, error) {
+	var tok token
+	var err error
+
+	tok, _, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	switch tok {
+	case slash:
+		return p.parseColonSlash()
+	default:
+		p.unscan()
+		return p.parseColonDefault()
+	}
+}
+
+// parseColonSlash extract :/<data> statements
+func (p *Parser) parseColonSlash() (Revisioner, error) {
+	var tok, nextTok token
+	var lit string
+	var re string
+	var negate bool
+	var err error
+
+	for {
+		tok, lit, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		nextTok, _, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		switch {
+		case tok == emark && nextTok == emark:
+			re += lit
+		case re == "" && tok == emark && nextTok == minus:
+			negate = true
+		case re == "" && tok == emark:
+			return nil, &ErrInvalidRevision{s: `revision suffix brace component sequences starting with "/!" others than those defined are reserved`}
+		case tok == eof:
+			p.unscan()
+			reg, err := regexp.Compile(re)
+
+			if err != nil {
+				return ColonReg{}, &ErrInvalidRevision{fmt.Sprintf(`revision suffix brace component, %s`, err.Error())}
+			}
+
+			return ColonReg{reg, negate}, nil
+		default:
+			p.unscan()
+			re += lit
+		}
+	}
+}
+
+// parseColonDefault extract :<data> statements
+func (p *Parser) parseColonDefault() (Revisioner, error) {
+	var tok token
+	var lit string
+	var path string
+	var stage int
+	var err error
+	var n = -1
+
+	tok, lit, err = p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	nextTok, _, err := p.scan()
+
+	if err != nil {
+		return nil, err
+	}
+
+	if tok == number && nextTok == colon {
+		n, _ = strconv.Atoi(lit)
+	}
+
+	switch n {
+	case 0, 1, 2, 3:
+		stage = n
+	default:
+		path += lit
+		p.unscan()
+	}
+
+	for {
+		tok, lit, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		switch {
+		case tok == eof && n == -1:
+			return ColonPath{path}, nil
+		case tok == eof:
+			return ColonStagePath{path, stage}, nil
+		default:
+			path += lit
+		}
+	}
+}
+
+// parseRef extract reference name
+func (p *Parser) parseRef() (Revisioner, error) {
+	var tok, prevTok token
+	var lit, buf string
+	var endOfRef bool
+	var err error
+
+	for {
+		tok, lit, err = p.scan()
+
+		if err != nil {
+			return nil, err
+		}
+
+		switch tok {
+		case eof, at, colon, tilde, caret:
+			endOfRef = true
+		}
+
+		err := p.checkRefFormat(tok, lit, prevTok, buf, endOfRef)
+
+		if err != nil {
+			return "", err
+		}
+
+		if endOfRef {
+			p.unscan()
+			return Ref(buf), nil
+		}
+
+		buf += lit
+		prevTok = tok
+	}
+}
+
+// checkRefFormat ensure reference name follow rules defined here :
+// https://git-scm.com/docs/git-check-ref-format
+func (p *Parser) checkRefFormat(token token, literal string, previousToken token, buffer string, endOfRef bool) error {
+	switch token {
+	case aslash, space, control, qmark, asterisk, obracket:
+		return &ErrInvalidRevision{fmt.Sprintf(`must not contains "%s"`, literal)}
+	}
+
+	switch {
+	case (token == dot || token == slash) && buffer == "":
+		return &ErrInvalidRevision{fmt.Sprintf(`must not start with "%s"`, literal)}
+	case previousToken == slash && endOfRef:
+		return &ErrInvalidRevision{`must not end with "/"`}
+	case previousToken == dot && endOfRef:
+		return &ErrInvalidRevision{`must not end with "."`}
+	case token == dot && previousToken == slash:
+		return &ErrInvalidRevision{`must not contains "/."`}
+	case previousToken == dot && token == dot:
+		return &ErrInvalidRevision{`must not contains ".."`}
+	case previousToken == slash && token == slash:
+		return &ErrInvalidRevision{`must not contains consecutively "/"`}
+	case (token == slash || endOfRef) && len(buffer) > 4 && buffer[len(buffer)-5:] == ".lock":
+		return &ErrInvalidRevision{"cannot end with .lock"}
+	}
+
+	return nil
+}

vendor/github.com/go-git/go-git/v5/internal/revision/scanner.go

@@ -0,0 +1,117 @@
+package revision
+
+import (
+	"bufio"
+	"io"
+	"unicode"
+)
+
+// runeCategoryValidator takes a rune as input and
+// validates it belongs to a rune category
+type runeCategoryValidator func(r rune) bool
+
+// tokenizeExpression aggregates a series of runes matching check predicate into a single
+// string and provides given tokenType as token type
+func tokenizeExpression(ch rune, tokenType token, check runeCategoryValidator, r *bufio.Reader) (token, string, error) {
+	var data []rune
+	data = append(data, ch)
+
+	for {
+		c, _, err := r.ReadRune()
+
+		if c == zeroRune {
+			break
+		}
+
+		if err != nil {
+			return tokenError, "", err
+		}
+
+		if check(c) {
+			data = append(data, c)
+		} else {
+			err := r.UnreadRune()
+
+			if err != nil {
+				return tokenError, "", err
+			}
+
+			return tokenType, string(data), nil
+		}
+	}
+
+	return tokenType, string(data), nil
+}
+
+var zeroRune = rune(0)
+
+// scanner represents a lexical scanner.
+type scanner struct {
+	r *bufio.Reader
+}
+
+// newScanner returns a new instance of scanner.
+func newScanner(r io.Reader) *scanner {
+	return &scanner{r: bufio.NewReader(r)}
+}
+
+// Scan extracts tokens and their strings counterpart
+// from the reader
+func (s *scanner) scan() (token, string, error) {
+	ch, _, err := s.r.ReadRune()
+
+	if err != nil && err != io.EOF {
+		return tokenError, "", err
+	}
+
+	switch ch {
+	case zeroRune:
+		return eof, "", nil
+	case ':':
+		return colon, string(ch), nil
+	case '~':
+		return tilde, string(ch), nil
+	case '^':
+		return caret, string(ch), nil
+	case '.':
+		return dot, string(ch), nil
+	case '/':
+		return slash, string(ch), nil
+	case '{':
+		return obrace, string(ch), nil
+	case '}':
+		return cbrace, string(ch), nil
+	case '-':
+		return minus, string(ch), nil
+	case '@':
+		return at, string(ch), nil
+	case '\\':
+		return aslash, string(ch), nil
+	case '?':
+		return qmark, string(ch), nil
+	case '*':
+		return asterisk, string(ch), nil
+	case '[':
+		return obracket, string(ch), nil
+	case '!':
+		return emark, string(ch), nil
+	}
+
+	if unicode.IsSpace(ch) {
+		return space, string(ch), nil
+	}
+
+	if unicode.IsControl(ch) {
+		return control, string(ch), nil
+	}
+
+	if unicode.IsLetter(ch) {
+		return tokenizeExpression(ch, word, unicode.IsLetter, s.r)
+	}
+
+	if unicode.IsNumber(ch) {
+		return tokenizeExpression(ch, number, unicode.IsNumber, s.r)
+	}
+
+	return tokenError, string(ch), nil
+}

vendor/github.com/go-git/go-git/v5/internal/revision/token.go

@@ -0,0 +1,28 @@
+package revision
+
+// token represents a entity extracted from string parsing
+type token int
+
+const (
+	eof token = iota
+
+	aslash
+	asterisk
+	at
+	caret
+	cbrace
+	colon
+	control
+	dot
+	emark
+	minus
+	number
+	obrace
+	obracket
+	qmark
+	slash
+	space
+	tilde
+	tokenError
+	word
+)

vendor/github.com/go-git/go-git/v5/internal/url/url.go

@@ -0,0 +1,39 @@
+package url
+
+import (
+	"regexp"
+)
+
+var (
+	isSchemeRegExp = regexp.MustCompile(`^[^:]+://`)
+
+	// Ref: https://github.com/git/git/blob/master/Documentation/urls.txt#L37
+	scpLikeUrlRegExp = regexp.MustCompile(`^(?:(?P<user>[^@]+)@)?(?P<host>[^:\s]+):(?:(?P<port>[0-9]{1,5}):)?(?P<path>[^\\].*)$`)
+)
+
+// MatchesScheme returns true if the given string matches a URL-like
+// format scheme.
+func MatchesScheme(url string) bool {
+	return isSchemeRegExp.MatchString(url)
+}
+
+// MatchesScpLike returns true if the given string matches an SCP-like
+// format scheme.
+func MatchesScpLike(url string) bool {
+	return scpLikeUrlRegExp.MatchString(url)
+}
+
+// FindScpLikeComponents returns the user, host, port and path of the
+// given SCP-like URL.
+func FindScpLikeComponents(url string) (user, host, port, path string) {
+	m := scpLikeUrlRegExp.FindStringSubmatch(url)
+	return m[1], m[2], m[3], m[4]
+}
+
+// IsLocalEndpoint returns true if the given URL string specifies a
+// local file endpoint.  For example, on a Linux machine,
+// `/home/user/src/go-git` would match as a local endpoint, but
+// `https://github.com/src-d/go-git` would not.
+func IsLocalEndpoint(url string) bool {
+	return !MatchesScheme(url) && !MatchesScpLike(url)
+}

vendor/github.com/go-git/go-git/v5/object_walker.go

@@ -0,0 +1,104 @@
+package git
+
+import (
+	"fmt"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/filemode"
+	"github.com/go-git/go-git/v5/plumbing/object"
+	"github.com/go-git/go-git/v5/storage"
+)
+
+type objectWalker struct {
+	Storer storage.Storer
+	// seen is the set of objects seen in the repo.
+	// seen map can become huge if walking over large
+	// repos. Thus using struct{} as the value type.
+	seen map[plumbing.Hash]struct{}
+}
+
+func newObjectWalker(s storage.Storer) *objectWalker {
+	return &objectWalker{s, map[plumbing.Hash]struct{}{}}
+}
+
+// walkAllRefs walks all (hash) references from the repo.
+func (p *objectWalker) walkAllRefs() error {
+	// Walk over all the references in the repo.
+	it, err := p.Storer.IterReferences()
+	if err != nil {
+		return err
+	}
+	defer it.Close()
+	err = it.ForEach(func(ref *plumbing.Reference) error {
+		// Exit this iteration early for non-hash references.
+		if ref.Type() != plumbing.HashReference {
+			return nil
+		}
+		return p.walkObjectTree(ref.Hash())
+	})
+	return err
+}
+
+func (p *objectWalker) isSeen(hash plumbing.Hash) bool {
+	_, seen := p.seen[hash]
+	return seen
+}
+
+func (p *objectWalker) add(hash plumbing.Hash) {
+	p.seen[hash] = struct{}{}
+}
+
+// walkObjectTree walks over all objects and remembers references
+// to them in the objectWalker. This is used instead of the revlist
+// walks because memory usage is tight with huge repos.
+func (p *objectWalker) walkObjectTree(hash plumbing.Hash) error {
+	// Check if we have already seen, and mark this object
+	if p.isSeen(hash) {
+		return nil
+	}
+	p.add(hash)
+	// Fetch the object.
+	obj, err := object.GetObject(p.Storer, hash)
+	if err != nil {
+		return fmt.Errorf("getting object %s failed: %v", hash, err)
+	}
+	// Walk all children depending on object type.
+	switch obj := obj.(type) {
+	case *object.Commit:
+		err = p.walkObjectTree(obj.TreeHash)
+		if err != nil {
+			return err
+		}
+		for _, h := range obj.ParentHashes {
+			err = p.walkObjectTree(h)
+			if err != nil {
+				return err
+			}
+		}
+	case *object.Tree:
+		for i := range obj.Entries {
+			// Shortcut for blob objects:
+			// 'or' the lower bits of a mode and check that it
+			// it matches a filemode.Executable. The type information
+			// is in the higher bits, but this is the cleanest way
+			// to handle plain files with different modes.
+			// Other non-tree objects are somewhat rare, so they
+			// are not special-cased.
+			if obj.Entries[i].Mode|0755 == filemode.Executable {
+				p.add(obj.Entries[i].Hash)
+				continue
+			}
+			// Normal walk for sub-trees (and symlinks etc).
+			err = p.walkObjectTree(obj.Entries[i].Hash)
+			if err != nil {
+				return err
+			}
+		}
+	case *object.Tag:
+		return p.walkObjectTree(obj.Target)
+	default:
+		// Error out on unhandled object types.
+		return fmt.Errorf("unknown object %X %s %T", obj.ID(), obj.Type(), obj)
+	}
+	return nil
+}

vendor/github.com/go-git/go-git/v5/options.go

@@ -0,0 +1,792 @@
+package git
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/go-git/go-git/v5/config"
+	"github.com/go-git/go-git/v5/plumbing"
+	formatcfg "github.com/go-git/go-git/v5/plumbing/format/config"
+	"github.com/go-git/go-git/v5/plumbing/object"
+	"github.com/go-git/go-git/v5/plumbing/protocol/packp/sideband"
+	"github.com/go-git/go-git/v5/plumbing/transport"
+)
+
+// SubmoduleRescursivity defines how depth will affect any submodule recursive
+// operation.
+type SubmoduleRescursivity uint
+
+const (
+	// DefaultRemoteName name of the default Remote, just like git command.
+	DefaultRemoteName = "origin"
+
+	// NoRecurseSubmodules disables the recursion for a submodule operation.
+	NoRecurseSubmodules SubmoduleRescursivity = 0
+	// DefaultSubmoduleRecursionDepth allow recursion in a submodule operation.
+	DefaultSubmoduleRecursionDepth SubmoduleRescursivity = 10
+)
+
+var (
+	ErrMissingURL = errors.New("URL field is required")
+)
+
+// CloneOptions describes how a clone should be performed.
+type CloneOptions struct {
+	// The (possibly remote) repository URL to clone from.
+	URL string
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+	// Name of the remote to be added, by default `origin`.
+	RemoteName string
+	// Remote branch to clone.
+	ReferenceName plumbing.ReferenceName
+	// Fetch only ReferenceName if true.
+	SingleBranch bool
+	// Mirror clones the repository as a mirror.
+	//
+	// Compared to a bare clone, mirror not only maps local branches of the
+	// source to local branches of the target, it maps all refs (including
+	// remote-tracking branches, notes etc.) and sets up a refspec configuration
+	// such that all these refs are overwritten by a git remote update in the
+	// target repository.
+	Mirror bool
+	// No checkout of HEAD after clone if true.
+	NoCheckout bool
+	// Limit fetching to the specified number of commits.
+	Depth int
+	// RecurseSubmodules after the clone is created, initialize all submodules
+	// within, using their default settings. This option is ignored if the
+	// cloned repository does not have a worktree.
+	RecurseSubmodules SubmoduleRescursivity
+	// ShallowSubmodules limit cloning submodules to the 1 level of depth.
+	// It matches the git command --shallow-submodules.
+	ShallowSubmodules bool
+	// Progress is where the human readable information sent by the server is
+	// stored, if nil nothing is stored and the capability (if supported)
+	// no-progress, is sent to the server to avoid send this information.
+	Progress sideband.Progress
+	// Tags describe how the tags will be fetched from the remote repository,
+	// by default is AllTags.
+	Tags TagMode
+	// InsecureSkipTLS skips ssl verify if protocol is https
+	InsecureSkipTLS bool
+	// CABundle specify additional ca bundle with system cert pool
+	CABundle []byte
+	// ProxyOptions provides info required for connecting to a proxy.
+	ProxyOptions transport.ProxyOptions
+	// When the repository to clone is on the local machine, instead of
+	// using hard links, automatically setup .git/objects/info/alternates
+	// to share the objects with the source repository.
+	// The resulting repository starts out without any object of its own.
+	// NOTE: this is a possibly dangerous operation; do not use it unless
+	// you understand what it does.
+	//
+	// [Reference]: https://git-scm.com/docs/git-clone#Documentation/git-clone.txt---shared
+	Shared bool
+}
+
+// MergeOptions describes how a merge should be performed.
+type MergeOptions struct {
+	// Strategy defines the merge strategy to be used.
+	Strategy MergeStrategy
+}
+
+// MergeStrategy represents the different types of merge strategies.
+type MergeStrategy int8
+
+const (
+	// FastForwardMerge represents a Git merge strategy where the current
+	// branch can be simply updated to point to the HEAD of the branch being
+	// merged. This is only possible if the history of the branch being merged
+	// is a linear descendant of the current branch, with no conflicting commits.
+	//
+	// This is the default option.
+	FastForwardMerge MergeStrategy = iota
+)
+
+// Validate validates the fields and sets the default values.
+func (o *CloneOptions) Validate() error {
+	if o.URL == "" {
+		return ErrMissingURL
+	}
+
+	if o.RemoteName == "" {
+		o.RemoteName = DefaultRemoteName
+	}
+
+	if o.ReferenceName == "" {
+		o.ReferenceName = plumbing.HEAD
+	}
+
+	if o.Tags == InvalidTagMode {
+		o.Tags = AllTags
+	}
+
+	return nil
+}
+
+// PullOptions describes how a pull should be performed.
+type PullOptions struct {
+	// Name of the remote to be pulled. If empty, uses the default.
+	RemoteName string
+	// RemoteURL overrides the remote repo address with a custom URL
+	RemoteURL string
+	// Remote branch to clone. If empty, uses HEAD.
+	ReferenceName plumbing.ReferenceName
+	// Fetch only ReferenceName if true.
+	SingleBranch bool
+	// Limit fetching to the specified number of commits.
+	Depth int
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+	// RecurseSubmodules controls if new commits of all populated submodules
+	// should be fetched too.
+	RecurseSubmodules SubmoduleRescursivity
+	// Progress is where the human readable information sent by the server is
+	// stored, if nil nothing is stored and the capability (if supported)
+	// no-progress, is sent to the server to avoid send this information.
+	Progress sideband.Progress
+	// Force allows the pull to update a local branch even when the remote
+	// branch does not descend from it.
+	Force bool
+	// InsecureSkipTLS skips ssl verify if protocol is https
+	InsecureSkipTLS bool
+	// CABundle specify additional ca bundle with system cert pool
+	CABundle []byte
+	// ProxyOptions provides info required for connecting to a proxy.
+	ProxyOptions transport.ProxyOptions
+}
+
+// Validate validates the fields and sets the default values.
+func (o *PullOptions) Validate() error {
+	if o.RemoteName == "" {
+		o.RemoteName = DefaultRemoteName
+	}
+
+	if o.ReferenceName == "" {
+		o.ReferenceName = plumbing.HEAD
+	}
+
+	return nil
+}
+
+type TagMode int
+
+const (
+	InvalidTagMode TagMode = iota
+	// TagFollowing any tag that points into the histories being fetched is also
+	// fetched. TagFollowing requires a server with `include-tag` capability
+	// in order to fetch the annotated tags objects.
+	TagFollowing
+	// AllTags fetch all tags from the remote (i.e., fetch remote tags
+	// refs/tags/* into local tags with the same name)
+	AllTags
+	// NoTags fetch no tags from the remote at all
+	NoTags
+)
+
+// FetchOptions describes how a fetch should be performed
+type FetchOptions struct {
+	// Name of the remote to fetch from. Defaults to origin.
+	RemoteName string
+	// RemoteURL overrides the remote repo address with a custom URL
+	RemoteURL string
+	RefSpecs  []config.RefSpec
+	// Depth limit fetching to the specified number of commits from the tip of
+	// each remote branch history.
+	Depth int
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+	// Progress is where the human readable information sent by the server is
+	// stored, if nil nothing is stored and the capability (if supported)
+	// no-progress, is sent to the server to avoid send this information.
+	Progress sideband.Progress
+	// Tags describe how the tags will be fetched from the remote repository,
+	// by default is TagFollowing.
+	Tags TagMode
+	// Force allows the fetch to update a local branch even when the remote
+	// branch does not descend from it.
+	Force bool
+	// InsecureSkipTLS skips ssl verify if protocol is https
+	InsecureSkipTLS bool
+	// CABundle specify additional ca bundle with system cert pool
+	CABundle []byte
+	// ProxyOptions provides info required for connecting to a proxy.
+	ProxyOptions transport.ProxyOptions
+	// Prune specify that local refs that match given RefSpecs and that do
+	// not exist remotely will be removed.
+	Prune bool
+}
+
+// Validate validates the fields and sets the default values.
+func (o *FetchOptions) Validate() error {
+	if o.RemoteName == "" {
+		o.RemoteName = DefaultRemoteName
+	}
+
+	if o.Tags == InvalidTagMode {
+		o.Tags = TagFollowing
+	}
+
+	for _, r := range o.RefSpecs {
+		if err := r.Validate(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// PushOptions describes how a push should be performed.
+type PushOptions struct {
+	// RemoteName is the name of the remote to be pushed to.
+	RemoteName string
+	// RemoteURL overrides the remote repo address with a custom URL
+	RemoteURL string
+	// RefSpecs specify what destination ref to update with what source object.
+	//
+	// The format of a <refspec> parameter is an optional plus +, followed by
+	//  the source object <src>, followed by a colon :, followed by the destination ref <dst>.
+	// The <src> is often the name of the branch you would want to push, but it can be a SHA-1.
+	// The <dst> tells which ref on the remote side is updated with this push.
+	//
+	// A refspec with empty src can be used to delete a reference.
+	RefSpecs []config.RefSpec
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+	// Progress is where the human readable information sent by the server is
+	// stored, if nil nothing is stored.
+	Progress sideband.Progress
+	// Prune specify that remote refs that match given RefSpecs and that do
+	// not exist locally will be removed.
+	Prune bool
+	// Force allows the push to update a remote branch even when the local
+	// branch does not descend from it.
+	Force bool
+	// InsecureSkipTLS skips ssl verify if protocol is https
+	InsecureSkipTLS bool
+	// CABundle specify additional ca bundle with system cert pool
+	CABundle []byte
+	// RequireRemoteRefs only allows a remote ref to be updated if its current
+	// value is the one specified here.
+	RequireRemoteRefs []config.RefSpec
+	// FollowTags will send any annotated tags with a commit target reachable from
+	// the refs already being pushed
+	FollowTags bool
+	// ForceWithLease allows a force push as long as the remote ref adheres to a "lease"
+	ForceWithLease *ForceWithLease
+	// PushOptions sets options to be transferred to the server during push.
+	Options map[string]string
+	// Atomic sets option to be an atomic push
+	Atomic bool
+	// ProxyOptions provides info required for connecting to a proxy.
+	ProxyOptions transport.ProxyOptions
+}
+
+// ForceWithLease sets fields on the lease
+// If neither RefName nor Hash are set, ForceWithLease protects
+// all refs in the refspec by ensuring the ref of the remote in the local repsitory
+// matches the one in the ref advertisement.
+type ForceWithLease struct {
+	// RefName, when set will protect the ref by ensuring it matches the
+	// hash in the ref advertisement.
+	RefName plumbing.ReferenceName
+	// Hash is the expected object id of RefName. The push will be rejected unless this
+	// matches the corresponding object id of RefName in the refs advertisement.
+	Hash plumbing.Hash
+}
+
+// Validate validates the fields and sets the default values.
+func (o *PushOptions) Validate() error {
+	if o.RemoteName == "" {
+		o.RemoteName = DefaultRemoteName
+	}
+
+	if len(o.RefSpecs) == 0 {
+		o.RefSpecs = []config.RefSpec{
+			config.RefSpec(config.DefaultPushRefSpec),
+		}
+	}
+
+	for _, r := range o.RefSpecs {
+		if err := r.Validate(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// SubmoduleUpdateOptions describes how a submodule update should be performed.
+type SubmoduleUpdateOptions struct {
+	// Init, if true initializes the submodules recorded in the index.
+	Init bool
+	// NoFetch tell to the update command to not fetch new objects from the
+	// remote site.
+	NoFetch bool
+	// RecurseSubmodules the update is performed not only in the submodules of
+	// the current repository but also in any nested submodules inside those
+	// submodules (and so on). Until the SubmoduleRescursivity is reached.
+	RecurseSubmodules SubmoduleRescursivity
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+	// Depth limit fetching to the specified number of commits from the tip of
+	// each remote branch history.
+	Depth int
+}
+
+var (
+	ErrBranchHashExclusive  = errors.New("Branch and Hash are mutually exclusive")
+	ErrCreateRequiresBranch = errors.New("Branch is mandatory when Create is used")
+)
+
+// CheckoutOptions describes how a checkout operation should be performed.
+type CheckoutOptions struct {
+	// Hash is the hash of a commit or tag to be checked out. If used, HEAD
+	// will be in detached mode. If Create is not used, Branch and Hash are
+	// mutually exclusive.
+	Hash plumbing.Hash
+	// Branch to be checked out, if Branch and Hash are empty is set to `master`.
+	Branch plumbing.ReferenceName
+	// Create a new branch named Branch and start it at Hash.
+	Create bool
+	// Force, if true when switching branches, proceed even if the index or the
+	// working tree differs from HEAD. This is used to throw away local changes
+	Force bool
+	// Keep, if true when switching branches, local changes (the index or the
+	// working tree changes) will be kept so that they can be committed to the
+	// target branch. Force and Keep are mutually exclusive, should not be both
+	// set to true.
+	Keep bool
+	// SparseCheckoutDirectories
+	SparseCheckoutDirectories []string
+}
+
+// Validate validates the fields and sets the default values.
+func (o *CheckoutOptions) Validate() error {
+	if !o.Create && !o.Hash.IsZero() && o.Branch != "" {
+		return ErrBranchHashExclusive
+	}
+
+	if o.Create && o.Branch == "" {
+		return ErrCreateRequiresBranch
+	}
+
+	if o.Branch == "" {
+		o.Branch = plumbing.Master
+	}
+
+	return nil
+}
+
+// ResetMode defines the mode of a reset operation.
+type ResetMode int8
+
+const (
+	// MixedReset resets the index but not the working tree (i.e., the changed
+	// files are preserved but not marked for commit) and reports what has not
+	// been updated. This is the default action.
+	MixedReset ResetMode = iota
+	// HardReset resets the index and working tree. Any changes to tracked files
+	// in the working tree are discarded.
+	HardReset
+	// MergeReset resets the index and updates the files in the working tree
+	// that are different between Commit and HEAD, but keeps those which are
+	// different between the index and working tree (i.e. which have changes
+	// which have not been added).
+	//
+	// If a file that is different between Commit and the index has unstaged
+	// changes, reset is aborted.
+	MergeReset
+	// SoftReset does not touch the index file or the working tree at all (but
+	// resets the head to <commit>, just like all modes do). This leaves all
+	// your changed files "Changes to be committed", as git status would put it.
+	SoftReset
+)
+
+// ResetOptions describes how a reset operation should be performed.
+type ResetOptions struct {
+	// Commit, if commit is present set the current branch head (HEAD) to it.
+	Commit plumbing.Hash
+	// Mode, form resets the current branch head to Commit and possibly updates
+	// the index (resetting it to the tree of Commit) and the working tree
+	// depending on Mode. If empty MixedReset is used.
+	Mode ResetMode
+}
+
+// Validate validates the fields and sets the default values.
+func (o *ResetOptions) Validate(r *Repository) error {
+	if o.Commit == plumbing.ZeroHash {
+		ref, err := r.Head()
+		if err != nil {
+			return err
+		}
+
+		o.Commit = ref.Hash()
+	} else {
+		_, err := r.CommitObject(o.Commit)
+		if err != nil {
+			return fmt.Errorf("invalid reset option: %w", err)
+		}
+	}
+
+	return nil
+}
+
+type LogOrder int8
+
+const (
+	LogOrderDefault LogOrder = iota
+	LogOrderDFS
+	LogOrderDFSPost
+	LogOrderBSF
+	LogOrderCommitterTime
+)
+
+// LogOptions describes how a log action should be performed.
+type LogOptions struct {
+	// When the From option is set the log will only contain commits
+	// reachable from it. If this option is not set, HEAD will be used as
+	// the default From.
+	From plumbing.Hash
+
+	// The default traversal algorithm is Depth-first search
+	// set Order=LogOrderCommitterTime for ordering by committer time (more compatible with `git log`)
+	// set Order=LogOrderBSF for Breadth-first search
+	Order LogOrder
+
+	// Show only those commits in which the specified file was inserted/updated.
+	// It is equivalent to running `git log -- <file-name>`.
+	// this field is kept for compatibility, it can be replaced with PathFilter
+	FileName *string
+
+	// Filter commits based on the path of files that are updated
+	// takes file path as argument and should return true if the file is desired
+	// It can be used to implement `git log -- <path>`
+	// either <path> is a file path, or directory path, or a regexp of file/directory path
+	PathFilter func(string) bool
+
+	// Pretend as if all the refs in refs/, along with HEAD, are listed on the command line as <commit>.
+	// It is equivalent to running `git log --all`.
+	// If set on true, the From option will be ignored.
+	All bool
+
+	// Show commits more recent than a specific date.
+	// It is equivalent to running `git log --since <date>` or `git log --after <date>`.
+	Since *time.Time
+
+	// Show commits older than a specific date.
+	// It is equivalent to running `git log --until <date>` or `git log --before <date>`.
+	Until *time.Time
+}
+
+var (
+	ErrMissingAuthor = errors.New("author field is required")
+)
+
+// AddOptions describes how an `add` operation should be performed
+type AddOptions struct {
+	// All equivalent to `git add -A`, update the index not only where the
+	// working tree has a file matching `Path` but also where the index already
+	// has an entry. This adds, modifies, and removes index entries to match the
+	// working tree.  If no `Path` nor `Glob` is given when `All` option is
+	// used, all files in the entire working tree are updated.
+	All bool
+	// Path is the exact filepath to the file or directory to be added.
+	Path string
+	// Glob adds all paths, matching pattern, to the index. If pattern matches a
+	// directory path, all directory contents are added to the index recursively.
+	Glob string
+	// SkipStatus adds the path with no status check. This option is relevant only
+	// when the `Path` option is specified and does not apply when the `All` option is used.
+	// Notice that when passing an ignored path it will be added anyway.
+	// When true it can speed up adding files to the worktree in very large repositories.
+	SkipStatus bool
+}
+
+// Validate validates the fields and sets the default values.
+func (o *AddOptions) Validate(r *Repository) error {
+	if o.Path != "" && o.Glob != "" {
+		return fmt.Errorf("fields Path and Glob are mutual exclusive")
+	}
+
+	return nil
+}
+
+// CommitOptions describes how a commit operation should be performed.
+type CommitOptions struct {
+	// All automatically stage files that have been modified and deleted, but
+	// new files you have not told Git about are not affected.
+	All bool
+	// AllowEmptyCommits enable empty commits to be created. An empty commit
+	// is when no changes to the tree were made, but a new commit message is
+	// provided. The default behavior is false, which results in ErrEmptyCommit.
+	AllowEmptyCommits bool
+	// Author is the author's signature of the commit. If Author is empty the
+	// Name and Email is read from the config, and time.Now it's used as When.
+	Author *object.Signature
+	// Committer is the committer's signature of the commit. If Committer is
+	// nil the Author signature is used.
+	Committer *object.Signature
+	// Parents are the parents commits for the new commit, by default when
+	// len(Parents) is zero, the hash of HEAD reference is used.
+	Parents []plumbing.Hash
+	// SignKey denotes a key to sign the commit with. A nil value here means the
+	// commit will not be signed. The private key must be present and already
+	// decrypted.
+	SignKey *openpgp.Entity
+	// Signer denotes a cryptographic signer to sign the commit with.
+	// A nil value here means the commit will not be signed.
+	// Takes precedence over SignKey.
+	Signer Signer
+	// Amend will create a new commit object and replace the commit that HEAD currently
+	// points to. Cannot be used with All nor Parents.
+	Amend bool
+}
+
+// Validate validates the fields and sets the default values.
+func (o *CommitOptions) Validate(r *Repository) error {
+	if o.All && o.Amend {
+		return errors.New("all and amend cannot be used together")
+	}
+
+	if o.Amend && len(o.Parents) > 0 {
+		return errors.New("parents cannot be used with amend")
+	}
+
+	if o.Author == nil {
+		if err := o.loadConfigAuthorAndCommitter(r); err != nil {
+			return err
+		}
+	}
+
+	if o.Committer == nil {
+		o.Committer = o.Author
+	}
+
+	if len(o.Parents) == 0 {
+		head, err := r.Head()
+		if err != nil && err != plumbing.ErrReferenceNotFound {
+			return err
+		}
+
+		if head != nil {
+			o.Parents = []plumbing.Hash{head.Hash()}
+		}
+	}
+
+	return nil
+}
+
+func (o *CommitOptions) loadConfigAuthorAndCommitter(r *Repository) error {
+	cfg, err := r.ConfigScoped(config.SystemScope)
+	if err != nil {
+		return err
+	}
+
+	if o.Author == nil && cfg.Author.Email != "" && cfg.Author.Name != "" {
+		o.Author = &object.Signature{
+			Name:  cfg.Author.Name,
+			Email: cfg.Author.Email,
+			When:  time.Now(),
+		}
+	}
+
+	if o.Committer == nil && cfg.Committer.Email != "" && cfg.Committer.Name != "" {
+		o.Committer = &object.Signature{
+			Name:  cfg.Committer.Name,
+			Email: cfg.Committer.Email,
+			When:  time.Now(),
+		}
+	}
+
+	if o.Author == nil && cfg.User.Email != "" && cfg.User.Name != "" {
+		o.Author = &object.Signature{
+			Name:  cfg.User.Name,
+			Email: cfg.User.Email,
+			When:  time.Now(),
+		}
+	}
+
+	if o.Author == nil {
+		return ErrMissingAuthor
+	}
+
+	return nil
+}
+
+var (
+	ErrMissingName    = errors.New("name field is required")
+	ErrMissingTagger  = errors.New("tagger field is required")
+	ErrMissingMessage = errors.New("message field is required")
+)
+
+// CreateTagOptions describes how a tag object should be created.
+type CreateTagOptions struct {
+	// Tagger defines the signature of the tag creator. If Tagger is empty the
+	// Name and Email is read from the config, and time.Now it's used as When.
+	Tagger *object.Signature
+	// Message defines the annotation of the tag. It is canonicalized during
+	// validation into the format expected by git - no leading whitespace and
+	// ending in a newline.
+	Message string
+	// SignKey denotes a key to sign the tag with. A nil value here means the tag
+	// will not be signed. The private key must be present and already decrypted.
+	SignKey *openpgp.Entity
+}
+
+// Validate validates the fields and sets the default values.
+func (o *CreateTagOptions) Validate(r *Repository, hash plumbing.Hash) error {
+	if o.Tagger == nil {
+		if err := o.loadConfigTagger(r); err != nil {
+			return err
+		}
+	}
+
+	if o.Message == "" {
+		return ErrMissingMessage
+	}
+
+	// Canonicalize the message into the expected message format.
+	o.Message = strings.TrimSpace(o.Message) + "\n"
+
+	return nil
+}
+
+func (o *CreateTagOptions) loadConfigTagger(r *Repository) error {
+	cfg, err := r.ConfigScoped(config.SystemScope)
+	if err != nil {
+		return err
+	}
+
+	if o.Tagger == nil && cfg.Author.Email != "" && cfg.Author.Name != "" {
+		o.Tagger = &object.Signature{
+			Name:  cfg.Author.Name,
+			Email: cfg.Author.Email,
+			When:  time.Now(),
+		}
+	}
+
+	if o.Tagger == nil && cfg.User.Email != "" && cfg.User.Name != "" {
+		o.Tagger = &object.Signature{
+			Name:  cfg.User.Name,
+			Email: cfg.User.Email,
+			When:  time.Now(),
+		}
+	}
+
+	if o.Tagger == nil {
+		return ErrMissingTagger
+	}
+
+	return nil
+}
+
+// ListOptions describes how a remote list should be performed.
+type ListOptions struct {
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+	// InsecureSkipTLS skips ssl verify if protocol is https
+	InsecureSkipTLS bool
+	// CABundle specify additional ca bundle with system cert pool
+	CABundle []byte
+	// PeelingOption defines how peeled objects are handled during a
+	// remote list.
+	PeelingOption PeelingOption
+	// ProxyOptions provides info required for connecting to a proxy.
+	ProxyOptions transport.ProxyOptions
+	// Timeout specifies the timeout in seconds for list operations
+	Timeout int
+}
+
+// PeelingOption represents the different ways to handle peeled references.
+//
+// Peeled references represent the underlying object of an annotated
+// (or signed) tag. Refer to upstream documentation for more info:
+// https://github.com/git/git/blob/master/Documentation/technical/reftable.txt
+type PeelingOption uint8
+
+const (
+	// IgnorePeeled ignores all peeled reference names. This is the default behavior.
+	IgnorePeeled PeelingOption = 0
+	// OnlyPeeled returns only peeled reference names.
+	OnlyPeeled PeelingOption = 1
+	// AppendPeeled appends peeled reference names to the reference list.
+	AppendPeeled PeelingOption = 2
+)
+
+// CleanOptions describes how a clean should be performed.
+type CleanOptions struct {
+	Dir bool
+}
+
+// GrepOptions describes how a grep should be performed.
+type GrepOptions struct {
+	// Patterns are compiled Regexp objects to be matched.
+	Patterns []*regexp.Regexp
+	// InvertMatch selects non-matching lines.
+	InvertMatch bool
+	// CommitHash is the hash of the commit from which worktree should be derived.
+	CommitHash plumbing.Hash
+	// ReferenceName is the branch or tag name from which worktree should be derived.
+	ReferenceName plumbing.ReferenceName
+	// PathSpecs are compiled Regexp objects of pathspec to use in the matching.
+	PathSpecs []*regexp.Regexp
+}
+
+var (
+	ErrHashOrReference = errors.New("ambiguous options, only one of CommitHash or ReferenceName can be passed")
+)
+
+// Validate validates the fields and sets the default values.
+//
+// TODO: deprecate in favor of Validate(r *Repository) in v6.
+func (o *GrepOptions) Validate(w *Worktree) error {
+	return o.validate(w.r)
+}
+
+func (o *GrepOptions) validate(r *Repository) error {
+	if !o.CommitHash.IsZero() && o.ReferenceName != "" {
+		return ErrHashOrReference
+	}
+
+	// If none of CommitHash and ReferenceName are provided, set commit hash of
+	// the repository's head.
+	if o.CommitHash.IsZero() && o.ReferenceName == "" {
+		ref, err := r.Head()
+		if err != nil {
+			return err
+		}
+		o.CommitHash = ref.Hash()
+	}
+
+	return nil
+}
+
+// PlainOpenOptions describes how opening a plain repository should be
+// performed.
+type PlainOpenOptions struct {
+	// DetectDotGit defines whether parent directories should be
+	// walked until a .git directory or file is found.
+	DetectDotGit bool
+	// Enable .git/commondir support (see https://git-scm.com/docs/gitrepository-layout#Documentation/gitrepository-layout.txt).
+	// NOTE: This option will only work with the filesystem storage.
+	EnableDotGitCommonDir bool
+}
+
+// Validate validates the fields and sets the default values.
+func (o *PlainOpenOptions) Validate() error { return nil }
+
+type PlainInitOptions struct {
+	InitOptions
+	// Determines if the repository will have a worktree (non-bare) or not (bare).
+	Bare         bool
+	ObjectFormat formatcfg.ObjectFormat
+}
+
+// Validate validates the fields and sets the default values.
+func (o *PlainInitOptions) Validate() error { return nil }

vendor/github.com/go-git/go-git/v5/oss-fuzz.sh

@@ -0,0 +1,35 @@
+#!/bin/bash -eu
+# Copyright 2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+
+
+go mod download
+go get github.com/AdamKorcz/go-118-fuzz-build/testing
+
+if [ "$SANITIZER" != "coverage" ]; then
+    sed -i '/func (s \*DecoderSuite) TestDecode(/,/^}/ s/^/\/\//' plumbing/format/config/decoder_test.go
+    sed -n '35,$p' plumbing/format/packfile/common_test.go >> plumbing/format/packfile/delta_test.go
+    sed -n '20,53p' plumbing/object/object_test.go >> plumbing/object/tree_test.go
+    sed -i 's|func Test|// func Test|' plumbing/transport/common_test.go
+fi
+
+compile_native_go_fuzzer $(pwd)/internal/revision                       FuzzParser              fuzz_parser
+compile_native_go_fuzzer $(pwd)/plumbing/format/config                  FuzzDecoder             fuzz_decoder_config
+compile_native_go_fuzzer $(pwd)/plumbing/format/packfile                FuzzPatchDelta          fuzz_patch_delta
+compile_native_go_fuzzer $(pwd)/plumbing/object                         FuzzParseSignedBytes    fuzz_parse_signed_bytes
+compile_native_go_fuzzer $(pwd)/plumbing/object                         FuzzDecode              fuzz_decode
+compile_native_go_fuzzer $(pwd)/plumbing/protocol/packp                 FuzzDecoder             fuzz_decoder_packp
+compile_native_go_fuzzer $(pwd)/plumbing/transport                      FuzzNewEndpoint         fuzz_new_endpoint

vendor/github.com/go-git/go-git/v5/plumbing/cache/buffer_lru.go

@@ -0,0 +1,98 @@
+package cache
+
+import (
+	"container/list"
+	"sync"
+)
+
+// BufferLRU implements an object cache with an LRU eviction policy and a
+// maximum size (measured in object size).
+type BufferLRU struct {
+	MaxSize FileSize
+
+	actualSize FileSize
+	ll         *list.List
+	cache      map[int64]*list.Element
+	mut        sync.Mutex
+}
+
+// NewBufferLRU creates a new BufferLRU with the given maximum size. The maximum
+// size will never be exceeded.
+func NewBufferLRU(maxSize FileSize) *BufferLRU {
+	return &BufferLRU{MaxSize: maxSize}
+}
+
+// NewBufferLRUDefault creates a new BufferLRU with the default cache size.
+func NewBufferLRUDefault() *BufferLRU {
+	return &BufferLRU{MaxSize: DefaultMaxSize}
+}
+
+type buffer struct {
+	Key   int64
+	Slice []byte
+}
+
+// Put puts a buffer into the cache. If the buffer is already in the cache, it
+// will be marked as used. Otherwise, it will be inserted. A buffers might
+// be evicted to make room for the new one.
+func (c *BufferLRU) Put(key int64, slice []byte) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	if c.cache == nil {
+		c.actualSize = 0
+		c.cache = make(map[int64]*list.Element, 1000)
+		c.ll = list.New()
+	}
+
+	bufSize := FileSize(len(slice))
+	if ee, ok := c.cache[key]; ok {
+		oldBuf := ee.Value.(buffer)
+		// in this case bufSize is a delta: new size - old size
+		bufSize -= FileSize(len(oldBuf.Slice))
+		c.ll.MoveToFront(ee)
+		ee.Value = buffer{key, slice}
+	} else {
+		if bufSize > c.MaxSize {
+			return
+		}
+		ee := c.ll.PushFront(buffer{key, slice})
+		c.cache[key] = ee
+	}
+
+	c.actualSize += bufSize
+	for c.actualSize > c.MaxSize {
+		last := c.ll.Back()
+		lastObj := last.Value.(buffer)
+		lastSize := FileSize(len(lastObj.Slice))
+
+		c.ll.Remove(last)
+		delete(c.cache, lastObj.Key)
+		c.actualSize -= lastSize
+	}
+}
+
+// Get returns a buffer by its key. It marks the buffer as used. If the buffer
+// is not in the cache, (nil, false) will be returned.
+func (c *BufferLRU) Get(key int64) ([]byte, bool) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	ee, ok := c.cache[key]
+	if !ok {
+		return nil, false
+	}
+
+	c.ll.MoveToFront(ee)
+	return ee.Value.(buffer).Slice, true
+}
+
+// Clear the content of this buffer cache.
+func (c *BufferLRU) Clear() {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	c.ll = nil
+	c.cache = nil
+	c.actualSize = 0
+}

vendor/github.com/go-git/go-git/v5/plumbing/cache/common.go

@@ -0,0 +1,39 @@
+package cache
+
+import "github.com/go-git/go-git/v5/plumbing"
+
+const (
+	Byte FileSize = 1 << (iota * 10)
+	KiByte
+	MiByte
+	GiByte
+)
+
+type FileSize int64
+
+const DefaultMaxSize FileSize = 96 * MiByte
+
+// Object is an interface to a object cache.
+type Object interface {
+	// Put puts the given object into the cache. Whether this object will
+	// actually be put into the cache or not is implementation specific.
+	Put(o plumbing.EncodedObject)
+	// Get gets an object from the cache given its hash. The second return value
+	// is true if the object was returned, and false otherwise.
+	Get(k plumbing.Hash) (plumbing.EncodedObject, bool)
+	// Clear clears every object from the cache.
+	Clear()
+}
+
+// Buffer is an interface to a buffer cache.
+type Buffer interface {
+	// Put puts a buffer into the cache. If the buffer is already in the cache,
+	// it will be marked as used. Otherwise, it will be inserted. Buffer might
+	// be evicted to make room for the new one.
+	Put(key int64, slice []byte)
+	// Get returns a buffer by its key. It marks the buffer as used. If the
+	// buffer is not in the cache, (nil, false) will be returned.
+	Get(key int64) ([]byte, bool)
+	// Clear clears every object from the cache.
+	Clear()
+}

vendor/github.com/go-git/go-git/v5/plumbing/cache/object_lru.go

@@ -0,0 +1,101 @@
+package cache
+
+import (
+	"container/list"
+	"sync"
+
+	"github.com/go-git/go-git/v5/plumbing"
+)
+
+// ObjectLRU implements an object cache with an LRU eviction policy and a
+// maximum size (measured in object size).
+type ObjectLRU struct {
+	MaxSize FileSize
+
+	actualSize FileSize
+	ll         *list.List
+	cache      map[interface{}]*list.Element
+	mut        sync.Mutex
+}
+
+// NewObjectLRU creates a new ObjectLRU with the given maximum size. The maximum
+// size will never be exceeded.
+func NewObjectLRU(maxSize FileSize) *ObjectLRU {
+	return &ObjectLRU{MaxSize: maxSize}
+}
+
+// NewObjectLRUDefault creates a new ObjectLRU with the default cache size.
+func NewObjectLRUDefault() *ObjectLRU {
+	return &ObjectLRU{MaxSize: DefaultMaxSize}
+}
+
+// Put puts an object into the cache. If the object is already in the cache, it
+// will be marked as used. Otherwise, it will be inserted. A single object might
+// be evicted to make room for the new object.
+func (c *ObjectLRU) Put(obj plumbing.EncodedObject) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	if c.cache == nil {
+		c.actualSize = 0
+		c.cache = make(map[interface{}]*list.Element, 1000)
+		c.ll = list.New()
+	}
+
+	objSize := FileSize(obj.Size())
+	key := obj.Hash()
+	if ee, ok := c.cache[key]; ok {
+		oldObj := ee.Value.(plumbing.EncodedObject)
+		// in this case objSize is a delta: new size - old size
+		objSize -= FileSize(oldObj.Size())
+		c.ll.MoveToFront(ee)
+		ee.Value = obj
+	} else {
+		if objSize > c.MaxSize {
+			return
+		}
+		ee := c.ll.PushFront(obj)
+		c.cache[key] = ee
+	}
+
+	c.actualSize += objSize
+	for c.actualSize > c.MaxSize {
+		last := c.ll.Back()
+		if last == nil {
+			c.actualSize = 0
+			break
+		}
+
+		lastObj := last.Value.(plumbing.EncodedObject)
+		lastSize := FileSize(lastObj.Size())
+
+		c.ll.Remove(last)
+		delete(c.cache, lastObj.Hash())
+		c.actualSize -= lastSize
+	}
+}
+
+// Get returns an object by its hash. It marks the object as used. If the object
+// is not in the cache, (nil, false) will be returned.
+func (c *ObjectLRU) Get(k plumbing.Hash) (plumbing.EncodedObject, bool) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	ee, ok := c.cache[k]
+	if !ok {
+		return nil, false
+	}
+
+	c.ll.MoveToFront(ee)
+	return ee.Value.(plumbing.EncodedObject), true
+}
+
+// Clear the content of this object cache.
+func (c *ObjectLRU) Clear() {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	c.ll = nil
+	c.cache = nil
+	c.actualSize = 0
+}

vendor/github.com/go-git/go-git/v5/plumbing/color/color.go

@@ -0,0 +1,38 @@
+package color
+
+// TODO read colors from a github.com/go-git/go-git/plumbing/format/config.Config struct
+// TODO implement color parsing, see https://github.com/git/git/blob/v2.26.2/color.c
+
+// Colors. See https://github.com/git/git/blob/v2.26.2/color.h#L24-L53.
+const (
+	Normal       = ""
+	Reset        = "\033[m"
+	Bold         = "\033[1m"
+	Red          = "\033[31m"
+	Green        = "\033[32m"
+	Yellow       = "\033[33m"
+	Blue         = "\033[34m"
+	Magenta      = "\033[35m"
+	Cyan         = "\033[36m"
+	BoldRed      = "\033[1;31m"
+	BoldGreen    = "\033[1;32m"
+	BoldYellow   = "\033[1;33m"
+	BoldBlue     = "\033[1;34m"
+	BoldMagenta  = "\033[1;35m"
+	BoldCyan     = "\033[1;36m"
+	FaintRed     = "\033[2;31m"
+	FaintGreen   = "\033[2;32m"
+	FaintYellow  = "\033[2;33m"
+	FaintBlue    = "\033[2;34m"
+	FaintMagenta = "\033[2;35m"
+	FaintCyan    = "\033[2;36m"
+	BgRed        = "\033[41m"
+	BgGreen      = "\033[42m"
+	BgYellow     = "\033[43m"
+	BgBlue       = "\033[44m"
+	BgMagenta    = "\033[45m"
+	BgCyan       = "\033[46m"
+	Faint        = "\033[2m"
+	FaintItalic  = "\033[2;3m"
+	Reverse      = "\033[7m"
+)

vendor/github.com/go-git/go-git/v5/plumbing/error.go

@@ -0,0 +1,35 @@
+package plumbing
+
+import "fmt"
+
+type PermanentError struct {
+	Err error
+}
+
+func NewPermanentError(err error) *PermanentError {
+	if err == nil {
+		return nil
+	}
+
+	return &PermanentError{Err: err}
+}
+
+func (e *PermanentError) Error() string {
+	return fmt.Sprintf("permanent client error: %s", e.Err.Error())
+}
+
+type UnexpectedError struct {
+	Err error
+}
+
+func NewUnexpectedError(err error) *UnexpectedError {
+	if err == nil {
+		return nil
+	}
+
+	return &UnexpectedError{Err: err}
+}
+
+func (e *UnexpectedError) Error() string {
+	return fmt.Sprintf("unexpected client error: %s", e.Err.Error())
+}

vendor/github.com/go-git/go-git/v5/plumbing/filemode/filemode.go

@@ -0,0 +1,188 @@
+package filemode
+
+import (
+	"encoding/binary"
+	"fmt"
+	"os"
+	"strconv"
+)
+
+// A FileMode represents the kind of tree entries used by git. It
+// resembles regular file systems modes, although FileModes are
+// considerably simpler (there are not so many), and there are some,
+// like Submodule that has no file system equivalent.
+type FileMode uint32
+
+const (
+	// Empty is used as the FileMode of tree elements when comparing
+	// trees in the following situations:
+	//
+	// - the mode of tree elements before their creation.  - the mode of
+	// tree elements after their deletion.  - the mode of unmerged
+	// elements when checking the index.
+	//
+	// Empty has no file system equivalent.  As Empty is the zero value
+	// of FileMode, it is also returned by New and
+	// NewFromOsNewFromOSFileMode along with an error, when they fail.
+	Empty FileMode = 0
+	// Dir represent a Directory.
+	Dir FileMode = 0040000
+	// Regular represent non-executable files.  Please note this is not
+	// the same as golang regular files, which include executable files.
+	Regular FileMode = 0100644
+	// Deprecated represent non-executable files with the group writable
+	// bit set.  This mode was supported by the first versions of git,
+	// but it has been deprecated nowadays.  This library uses them
+	// internally, so you can read old packfiles, but will treat them as
+	// Regulars when interfacing with the outside world.  This is the
+	// standard git behaviour.
+	Deprecated FileMode = 0100664
+	// Executable represents executable files.
+	Executable FileMode = 0100755
+	// Symlink represents symbolic links to files.
+	Symlink FileMode = 0120000
+	// Submodule represents git submodules.  This mode has no file system
+	// equivalent.
+	Submodule FileMode = 0160000
+)
+
+// New takes the octal string representation of a FileMode and returns
+// the FileMode and a nil error.  If the string can not be parsed to a
+// 32 bit unsigned octal number, it returns Empty and the parsing error.
+//
+// Example: "40000" means Dir, "100644" means Regular.
+//
+// Please note this function does not check if the returned FileMode
+// is valid in git or if it is malformed.  For instance, "1" will
+// return the malformed FileMode(1) and a nil error.
+func New(s string) (FileMode, error) {
+	n, err := strconv.ParseUint(s, 8, 32)
+	if err != nil {
+		return Empty, err
+	}
+
+	return FileMode(n), nil
+}
+
+// NewFromOSFileMode returns the FileMode used by git to represent
+// the provided file system modes and a nil error on success.  If the
+// file system mode cannot be mapped to any valid git mode (as with
+// sockets or named pipes), it will return Empty and an error.
+//
+// Note that some git modes cannot be generated from os.FileModes, like
+// Deprecated and Submodule; while Empty will be returned, along with an
+// error, only when the method fails.
+func NewFromOSFileMode(m os.FileMode) (FileMode, error) {
+	if m.IsRegular() {
+		if isSetTemporary(m) {
+			return Empty, fmt.Errorf("no equivalent git mode for %s", m)
+		}
+		if isSetCharDevice(m) {
+			return Empty, fmt.Errorf("no equivalent git mode for %s", m)
+		}
+		if isSetUserExecutable(m) {
+			return Executable, nil
+		}
+		return Regular, nil
+	}
+
+	if m.IsDir() {
+		return Dir, nil
+	}
+
+	if isSetSymLink(m) {
+		return Symlink, nil
+	}
+
+	return Empty, fmt.Errorf("no equivalent git mode for %s", m)
+}
+
+func isSetCharDevice(m os.FileMode) bool {
+	return m&os.ModeCharDevice != 0
+}
+
+func isSetTemporary(m os.FileMode) bool {
+	return m&os.ModeTemporary != 0
+}
+
+func isSetUserExecutable(m os.FileMode) bool {
+	return m&0100 != 0
+}
+
+func isSetSymLink(m os.FileMode) bool {
+	return m&os.ModeSymlink != 0
+}
+
+// Bytes return a slice of 4 bytes with the mode in little endian
+// encoding.
+func (m FileMode) Bytes() []byte {
+	ret := make([]byte, 4)
+	binary.LittleEndian.PutUint32(ret, uint32(m))
+	return ret
+}
+
+// IsMalformed returns if the FileMode should not appear in a git packfile,
+// this is: Empty and any other mode not mentioned as a constant in this
+// package.
+func (m FileMode) IsMalformed() bool {
+	return m != Dir &&
+		m != Regular &&
+		m != Deprecated &&
+		m != Executable &&
+		m != Symlink &&
+		m != Submodule
+}
+
+// String returns the FileMode as a string in the standard git format,
+// this is, an octal number padded with ceros to 7 digits.  Malformed
+// modes are printed in that same format, for easier debugging.
+//
+// Example: Regular is "0100644", Empty is "0000000".
+func (m FileMode) String() string {
+	return fmt.Sprintf("%07o", uint32(m))
+}
+
+// IsRegular returns if the FileMode represents that of a regular file,
+// this is, either Regular or Deprecated.  Please note that Executable
+// are not regular even though in the UNIX tradition, they usually are:
+// See the IsFile method.
+func (m FileMode) IsRegular() bool {
+	return m == Regular ||
+		m == Deprecated
+}
+
+// IsFile returns if the FileMode represents that of a file, this is,
+// Regular, Deprecated, Executable or Link.
+func (m FileMode) IsFile() bool {
+	return m == Regular ||
+		m == Deprecated ||
+		m == Executable ||
+		m == Symlink
+}
+
+// ToOSFileMode returns the os.FileMode to be used when creating file
+// system elements with the given git mode and a nil error on success.
+//
+// When the provided mode cannot be mapped to a valid file system mode
+// (e.g.  Submodule) it returns os.FileMode(0) and an error.
+//
+// The returned file mode does not take into account the umask.
+func (m FileMode) ToOSFileMode() (os.FileMode, error) {
+	switch m {
+	case Dir:
+		return os.ModePerm | os.ModeDir, nil
+	case Submodule:
+		return os.ModePerm | os.ModeDir, nil
+	case Regular:
+		return os.FileMode(0644), nil
+	// Deprecated is no longer allowed: treated as a Regular instead
+	case Deprecated:
+		return os.FileMode(0644), nil
+	case Executable:
+		return os.FileMode(0755), nil
+	case Symlink:
+		return os.ModePerm | os.ModeSymlink, nil
+	}
+
+	return os.FileMode(0), fmt.Errorf("malformed mode (%s)", m)
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/config/common.go

@@ -0,0 +1,109 @@
+package config
+
+// New creates a new config instance.
+func New() *Config {
+	return &Config{}
+}
+
+// Config contains all the sections, comments and includes from a config file.
+type Config struct {
+	Comment  *Comment
+	Sections Sections
+	Includes Includes
+}
+
+// Includes is a list of Includes in a config file.
+type Includes []*Include
+
+// Include is a reference to an included config file.
+type Include struct {
+	Path   string
+	Config *Config
+}
+
+// Comment string without the prefix '#' or ';'.
+type Comment string
+
+const (
+	// NoSubsection token is passed to Config.Section and Config.SetSection to
+	// represent the absence of a section.
+	NoSubsection = ""
+)
+
+// Section returns a existing section with the given name or creates a new one.
+func (c *Config) Section(name string) *Section {
+	for i := len(c.Sections) - 1; i >= 0; i-- {
+		s := c.Sections[i]
+		if s.IsName(name) {
+			return s
+		}
+	}
+
+	s := &Section{Name: name}
+	c.Sections = append(c.Sections, s)
+	return s
+}
+
+// HasSection checks if the Config has a section with the specified name.
+func (c *Config) HasSection(name string) bool {
+	for _, s := range c.Sections {
+		if s.IsName(name) {
+			return true
+		}
+	}
+	return false
+}
+
+// RemoveSection removes a section from a config file.
+func (c *Config) RemoveSection(name string) *Config {
+	result := Sections{}
+	for _, s := range c.Sections {
+		if !s.IsName(name) {
+			result = append(result, s)
+		}
+	}
+
+	c.Sections = result
+	return c
+}
+
+// RemoveSubsection remove a subsection from a config file.
+func (c *Config) RemoveSubsection(section string, subsection string) *Config {
+	for _, s := range c.Sections {
+		if s.IsName(section) {
+			result := Subsections{}
+			for _, ss := range s.Subsections {
+				if !ss.IsName(subsection) {
+					result = append(result, ss)
+				}
+			}
+			s.Subsections = result
+		}
+	}
+
+	return c
+}
+
+// AddOption adds an option to a given section and subsection. Use the
+// NoSubsection constant for the subsection argument if no subsection is wanted.
+func (c *Config) AddOption(section string, subsection string, key string, value string) *Config {
+	if subsection == "" {
+		c.Section(section).AddOption(key, value)
+	} else {
+		c.Section(section).Subsection(subsection).AddOption(key, value)
+	}
+
+	return c
+}
+
+// SetOption sets an option to a given section and subsection. Use the
+// NoSubsection constant for the subsection argument if no subsection is wanted.
+func (c *Config) SetOption(section string, subsection string, key string, value string) *Config {
+	if subsection == "" {
+		c.Section(section).SetOption(key, value)
+	} else {
+		c.Section(section).Subsection(subsection).SetOption(key, value)
+	}
+
+	return c
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/config/decoder.go

@@ -0,0 +1,37 @@
+package config
+
+import (
+	"io"
+
+	"github.com/go-git/gcfg"
+)
+
+// A Decoder reads and decodes config files from an input stream.
+type Decoder struct {
+	io.Reader
+}
+
+// NewDecoder returns a new decoder that reads from r.
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{r}
+}
+
+// Decode reads the whole config from its input and stores it in the
+// value pointed to by config.
+func (d *Decoder) Decode(config *Config) error {
+	cb := func(s string, ss string, k string, v string, bv bool) error {
+		if ss == "" && k == "" {
+			config.Section(s)
+			return nil
+		}
+
+		if ss != "" && k == "" {
+			config.Section(s).Subsection(ss)
+			return nil
+		}
+
+		config.AddOption(s, ss, k, v)
+		return nil
+	}
+	return gcfg.ReadWithCallback(d, cb)
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/config/doc.go

@@ -0,0 +1,121 @@
+// Package config implements encoding and decoding of git config files.
+//
+//	Configuration File
+//	------------------
+//
+//	The Git configuration file contains a number of variables that affect
+//	the Git commands' behavior. The `.git/config` file in each repository
+//	is used to store the configuration for that repository, and
+//	`$HOME/.gitconfig` is used to store a per-user configuration as
+//	fallback values for the `.git/config` file. The file `/etc/gitconfig`
+//	can be used to store a system-wide default configuration.
+//
+//	The configuration variables are used by both the Git plumbing
+//	and the porcelains. The variables are divided into sections, wherein
+//	the fully qualified variable name of the variable itself is the last
+//	dot-separated segment and the section name is everything before the last
+//	dot. The variable names are case-insensitive, allow only alphanumeric
+//	characters and `-`, and must start with an alphabetic character.  Some
+//	variables may appear multiple times; we say then that the variable is
+//	multivalued.
+//
+//	Syntax
+//	~~~~~~
+//
+//	The syntax is fairly flexible and permissive; whitespaces are mostly
+//	ignored.  The '#' and ';' characters begin comments to the end of line,
+//	blank lines are ignored.
+//
+//	The file consists of sections and variables.  A section begins with
+//	the name of the section in square brackets and continues until the next
+//	section begins.  Section names are case-insensitive.  Only alphanumeric
+//	characters, `-` and `.` are allowed in section names.  Each variable
+//	must belong to some section, which means that there must be a section
+//	header before the first setting of a variable.
+//
+//	Sections can be further divided into subsections.  To begin a subsection
+//	put its name in double quotes, separated by space from the section name,
+//	in the section header, like in the example below:
+//
+//	--------
+//		[section "subsection"]
+//
+//	--------
+//
+//	Subsection names are case sensitive and can contain any characters except
+//	newline (doublequote `"` and backslash can be included by escaping them
+//	as `\"` and `\\`, respectively).  Section headers cannot span multiple
+//	lines.  Variables may belong directly to a section or to a given subsection.
+//	You can have `[section]` if you have `[section "subsection"]`, but you
+//	don't need to.
+//
+//	There is also a deprecated `[section.subsection]` syntax. With this
+//	syntax, the subsection name is converted to lower-case and is also
+//	compared case sensitively. These subsection names follow the same
+//	restrictions as section names.
+//
+//	All the other lines (and the remainder of the line after the section
+//	header) are recognized as setting variables, in the form
+//	'name = value' (or just 'name', which is a short-hand to say that
+//	the variable is the boolean "true").
+//	The variable names are case-insensitive, allow only alphanumeric characters
+//	and `-`, and must start with an alphabetic character.
+//
+//	A line that defines a value can be continued to the next line by
+//	ending it with a `\`; the backquote and the end-of-line are
+//	stripped.  Leading whitespaces after 'name =', the remainder of the
+//	line after the first comment character '#' or ';', and trailing
+//	whitespaces of the line are discarded unless they are enclosed in
+//	double quotes.  Internal whitespaces within the value are retained
+//	verbatim.
+//
+//	Inside double quotes, double quote `"` and backslash `\` characters
+//	must be escaped: use `\"` for `"` and `\\` for `\`.
+//
+//	The following escape sequences (beside `\"` and `\\`) are recognized:
+//	`\n` for newline character (NL), `\t` for horizontal tabulation (HT, TAB)
+//	and `\b` for backspace (BS).  Other char escape sequences (including octal
+//	escape sequences) are invalid.
+//
+//	Includes
+//	~~~~~~~~
+//
+//	You can include one config file from another by setting the special
+//	`include.path` variable to the name of the file to be included. The
+//	variable takes a pathname as its value, and is subject to tilde
+//	expansion.
+//
+//	The included file is expanded immediately, as if its contents had been
+//	found at the location of the include directive. If the value of the
+//	`include.path` variable is a relative path, the path is considered to be
+//	relative to the configuration file in which the include directive was
+//	found.  See below for examples.
+//
+//
+//	Example
+//	~~~~~~~
+//
+//		# Core variables
+//		[core]
+//			; Don't trust file modes
+//			filemode = false
+//
+//		# Our diff algorithm
+//		[diff]
+//			external = /usr/local/bin/diff-wrapper
+//			renames = true
+//
+//		[branch "devel"]
+//			remote = origin
+//			merge = refs/heads/devel
+//
+//		# Proxy settings
+//		[core]
+//			gitProxy="ssh" for "kernel.org"
+//			gitProxy=default-proxy ; for the rest
+//
+//		[include]
+//			path = /path/to/foo.inc ; include by absolute path
+//			path = foo ; expand "foo" relative to the current file
+//			path = ~/foo ; expand "foo" in your `$HOME` directory
+package config

vendor/github.com/go-git/go-git/v5/plumbing/format/config/encoder.go

@@ -0,0 +1,83 @@
+package config
+
+import (
+	"fmt"
+	"io"
+	"strings"
+)
+
+// An Encoder writes config files to an output stream.
+type Encoder struct {
+	w io.Writer
+}
+
+var (
+	subsectionReplacer = strings.NewReplacer(`"`, `\"`, `\`, `\\`)
+	valueReplacer      = strings.NewReplacer(`"`, `\"`, `\`, `\\`, "\n", `\n`, "\t", `\t`, "\b", `\b`)
+)
+
+// NewEncoder returns a new encoder that writes to w.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{w}
+}
+
+// Encode writes the config in git config format to the stream of the encoder.
+func (e *Encoder) Encode(cfg *Config) error {
+	for _, s := range cfg.Sections {
+		if err := e.encodeSection(s); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *Encoder) encodeSection(s *Section) error {
+	if len(s.Options) > 0 {
+		if err := e.printf("[%s]\n", s.Name); err != nil {
+			return err
+		}
+
+		if err := e.encodeOptions(s.Options); err != nil {
+			return err
+		}
+	}
+
+	for _, ss := range s.Subsections {
+		if err := e.encodeSubsection(s.Name, ss); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *Encoder) encodeSubsection(sectionName string, s *Subsection) error {
+	if err := e.printf("[%s \"%s\"]\n", sectionName, subsectionReplacer.Replace(s.Name)); err != nil {
+		return err
+	}
+
+	return e.encodeOptions(s.Options)
+}
+
+func (e *Encoder) encodeOptions(opts Options) error {
+	for _, o := range opts {
+		var value string
+		if strings.ContainsAny(o.Value, "#;\"\t\n\\") || strings.HasPrefix(o.Value, " ") || strings.HasSuffix(o.Value, " ") {
+			value = `"` + valueReplacer.Replace(o.Value) + `"`
+		} else {
+			value = o.Value
+		}
+
+		if err := e.printf("\t%s = %s\n", o.Key, value); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *Encoder) printf(msg string, args ...interface{}) error {
+	_, err := fmt.Fprintf(e.w, msg, args...)
+	return err
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/config/format.go

@@ -0,0 +1,53 @@
+package config
+
+// RepositoryFormatVersion represents the repository format version,
+// as per defined at:
+//
+//	https://git-scm.com/docs/repository-version
+type RepositoryFormatVersion string
+
+const (
+	// Version_0 is the format defined by the initial version of git,
+	// including but not limited to the format of the repository
+	// directory, the repository configuration file, and the object
+	// and ref storage.
+	//
+	// Specifying the complete behavior of git is beyond the scope
+	// of this document.
+	Version_0 = "0"
+
+	// Version_1 is identical to version 0, with the following exceptions:
+	//
+	//   1. When reading the core.repositoryformatversion variable, a git
+	//		implementation which supports version 1 MUST also read any
+	//		configuration keys found in the extensions section of the
+	//		configuration file.
+	//
+	//	 2. If a version-1 repository specifies any extensions.* keys that
+	//		the running git has not implemented, the operation MUST NOT proceed.
+	//		Similarly, if the value of any known key is not understood by the
+	//		implementation, the operation MUST NOT proceed.
+	//
+	// Note that if no extensions are specified in the config file, then
+	// core.repositoryformatversion SHOULD be set to 0 (setting it to 1 provides
+	// no benefit, and makes the repository incompatible with older
+	// implementations of git).
+	Version_1 = "1"
+
+	// DefaultRepositoryFormatVersion holds the default repository format version.
+	DefaultRepositoryFormatVersion = Version_0
+)
+
+// ObjectFormat defines the object format.
+type ObjectFormat string
+
+const (
+	// SHA1 represents the object format used for SHA1.
+	SHA1 ObjectFormat = "sha1"
+
+	// SHA256 represents the object format used for SHA256.
+	SHA256 ObjectFormat = "sha256"
+
+	// DefaultObjectFormat holds the default object format.
+	DefaultObjectFormat = SHA1
+)

vendor/github.com/go-git/go-git/v5/plumbing/format/config/option.go

@@ -0,0 +1,127 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+)
+
+// Option defines a key/value entity in a config file.
+type Option struct {
+	// Key preserving original caseness.
+	// Use IsKey instead to compare key regardless of caseness.
+	Key string
+	// Original value as string, could be not normalized.
+	Value string
+}
+
+type Options []*Option
+
+// IsKey returns true if the given key matches
+// this option's key in a case-insensitive comparison.
+func (o *Option) IsKey(key string) bool {
+	return strings.EqualFold(o.Key, key)
+}
+
+func (opts Options) GoString() string {
+	var strs []string
+	for _, opt := range opts {
+		strs = append(strs, fmt.Sprintf("%#v", opt))
+	}
+
+	return strings.Join(strs, ", ")
+}
+
+// Get gets the value for the given key if set,
+// otherwise it returns the empty string.
+//
+// # Note that there is no difference
+//
+// This matches git behaviour since git v1.8.1-rc1,
+// if there are multiple definitions of a key, the
+// last one wins.
+//
+// See: http://article.gmane.org/gmane.linux.kernel/1407184
+//
+// In order to get all possible values for the same key,
+// use GetAll.
+func (opts Options) Get(key string) string {
+	for i := len(opts) - 1; i >= 0; i-- {
+		o := opts[i]
+		if o.IsKey(key) {
+			return o.Value
+		}
+	}
+	return ""
+}
+
+// Has checks if an Option exist with the given key.
+func (opts Options) Has(key string) bool {
+	for _, o := range opts {
+		if o.IsKey(key) {
+			return true
+		}
+	}
+	return false
+}
+
+// GetAll returns all possible values for the same key.
+func (opts Options) GetAll(key string) []string {
+	result := []string{}
+	for _, o := range opts {
+		if o.IsKey(key) {
+			result = append(result, o.Value)
+		}
+	}
+	return result
+}
+
+func (opts Options) withoutOption(key string) Options {
+	result := Options{}
+	for _, o := range opts {
+		if !o.IsKey(key) {
+			result = append(result, o)
+		}
+	}
+	return result
+}
+
+func (opts Options) withAddedOption(key string, value string) Options {
+	return append(opts, &Option{key, value})
+}
+
+func (opts Options) withSettedOption(key string, values ...string) Options {
+	var result Options
+	var added []string
+	for _, o := range opts {
+		if !o.IsKey(key) {
+			result = append(result, o)
+			continue
+		}
+
+		if contains(values, o.Value) {
+			added = append(added, o.Value)
+			result = append(result, o)
+			continue
+		}
+	}
+
+	for _, value := range values {
+		if contains(added, value) {
+			continue
+		}
+
+		result = result.withAddedOption(key, value)
+	}
+
+	return result
+}
+
+func contains(haystack []string, needle string) bool {
+	for _, s := range haystack {
+		if s == needle {
+			return true
+		}
+	}
+
+	return false
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/config/section.go

@@ -0,0 +1,180 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+)
+
+// Section is the representation of a section inside git configuration files.
+// Each Section contains Options that are used by both the Git plumbing
+// and the porcelains.
+// Sections can be further divided into subsections. To begin a subsection
+// put its name in double quotes, separated by space from the section name,
+// in the section header, like in the example below:
+//
+//	[section "subsection"]
+//
+// All the other lines (and the remainder of the line after the section header)
+// are recognized as option variables, in the form "name = value" (or just name,
+// which is a short-hand to say that the variable is the boolean "true").
+// The variable names are case-insensitive, allow only alphanumeric characters
+// and -, and must start with an alphabetic character:
+//
+//	[section "subsection1"]
+//	    option1 = value1
+//	    option2
+//	[section "subsection2"]
+//	    option3 = value2
+type Section struct {
+	Name        string
+	Options     Options
+	Subsections Subsections
+}
+
+type Subsection struct {
+	Name    string
+	Options Options
+}
+
+type Sections []*Section
+
+func (s Sections) GoString() string {
+	var strs []string
+	for _, ss := range s {
+		strs = append(strs, fmt.Sprintf("%#v", ss))
+	}
+
+	return strings.Join(strs, ", ")
+}
+
+type Subsections []*Subsection
+
+func (s Subsections) GoString() string {
+	var strs []string
+	for _, ss := range s {
+		strs = append(strs, fmt.Sprintf("%#v", ss))
+	}
+
+	return strings.Join(strs, ", ")
+}
+
+// IsName checks if the name provided is equals to the Section name, case insensitive.
+func (s *Section) IsName(name string) bool {
+	return strings.EqualFold(s.Name, name)
+}
+
+// Subsection returns a Subsection from the specified Section. If the
+// Subsection does not exists, new one is created and added to Section.
+func (s *Section) Subsection(name string) *Subsection {
+	for i := len(s.Subsections) - 1; i >= 0; i-- {
+		ss := s.Subsections[i]
+		if ss.IsName(name) {
+			return ss
+		}
+	}
+
+	ss := &Subsection{Name: name}
+	s.Subsections = append(s.Subsections, ss)
+	return ss
+}
+
+// HasSubsection checks if the Section has a Subsection with the specified name.
+func (s *Section) HasSubsection(name string) bool {
+	for _, ss := range s.Subsections {
+		if ss.IsName(name) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// RemoveSubsection removes a subsection from a Section.
+func (s *Section) RemoveSubsection(name string) *Section {
+	result := Subsections{}
+	for _, s := range s.Subsections {
+		if !s.IsName(name) {
+			result = append(result, s)
+		}
+	}
+
+	s.Subsections = result
+	return s
+}
+
+// Option returns the value for the specified key. Empty string is returned if
+// key does not exists.
+func (s *Section) Option(key string) string {
+	return s.Options.Get(key)
+}
+
+// OptionAll returns all possible values for an option with the specified key.
+// If the option does not exists, an empty slice will be returned.
+func (s *Section) OptionAll(key string) []string {
+	return s.Options.GetAll(key)
+}
+
+// HasOption checks if the Section has an Option with the given key.
+func (s *Section) HasOption(key string) bool {
+	return s.Options.Has(key)
+}
+
+// AddOption adds a new Option to the Section. The updated Section is returned.
+func (s *Section) AddOption(key string, value string) *Section {
+	s.Options = s.Options.withAddedOption(key, value)
+	return s
+}
+
+// SetOption adds a new Option to the Section. If the option already exists, is replaced.
+// The updated Section is returned.
+func (s *Section) SetOption(key string, value string) *Section {
+	s.Options = s.Options.withSettedOption(key, value)
+	return s
+}
+
+// Remove an option with the specified key. The updated Section is returned.
+func (s *Section) RemoveOption(key string) *Section {
+	s.Options = s.Options.withoutOption(key)
+	return s
+}
+
+// IsName checks if the name of the subsection is exactly the specified name.
+func (s *Subsection) IsName(name string) bool {
+	return s.Name == name
+}
+
+// Option returns an option with the specified key. If the option does not exists,
+// empty spring will be returned.
+func (s *Subsection) Option(key string) string {
+	return s.Options.Get(key)
+}
+
+// OptionAll returns all possible values for an option with the specified key.
+// If the option does not exists, an empty slice will be returned.
+func (s *Subsection) OptionAll(key string) []string {
+	return s.Options.GetAll(key)
+}
+
+// HasOption checks if the Subsection has an Option with the given key.
+func (s *Subsection) HasOption(key string) bool {
+	return s.Options.Has(key)
+}
+
+// AddOption adds a new Option to the Subsection. The updated Subsection is returned.
+func (s *Subsection) AddOption(key string, value string) *Subsection {
+	s.Options = s.Options.withAddedOption(key, value)
+	return s
+}
+
+// SetOption adds a new Option to the Subsection. If the option already exists, is replaced.
+// The updated Subsection is returned.
+func (s *Subsection) SetOption(key string, value ...string) *Subsection {
+	s.Options = s.Options.withSettedOption(key, value...)
+	return s
+}
+
+// RemoveOption removes the option with the specified key. The updated Subsection is returned.
+func (s *Subsection) RemoveOption(key string) *Subsection {
+	s.Options = s.Options.withoutOption(key)
+	return s
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/diff/colorconfig.go

@@ -0,0 +1,97 @@
+package diff
+
+import "github.com/go-git/go-git/v5/plumbing/color"
+
+// A ColorKey is a key into a ColorConfig map and also equal to the key in the
+// diff.color subsection of the config. See
+// https://github.com/git/git/blob/v2.26.2/diff.c#L83-L106.
+type ColorKey string
+
+// ColorKeys.
+const (
+	Context                   ColorKey = "context"
+	Meta                      ColorKey = "meta"
+	Frag                      ColorKey = "frag"
+	Old                       ColorKey = "old"
+	New                       ColorKey = "new"
+	Commit                    ColorKey = "commit"
+	Whitespace                ColorKey = "whitespace"
+	Func                      ColorKey = "func"
+	OldMoved                  ColorKey = "oldMoved"
+	OldMovedAlternative       ColorKey = "oldMovedAlternative"
+	OldMovedDimmed            ColorKey = "oldMovedDimmed"
+	OldMovedAlternativeDimmed ColorKey = "oldMovedAlternativeDimmed"
+	NewMoved                  ColorKey = "newMoved"
+	NewMovedAlternative       ColorKey = "newMovedAlternative"
+	NewMovedDimmed            ColorKey = "newMovedDimmed"
+	NewMovedAlternativeDimmed ColorKey = "newMovedAlternativeDimmed"
+	ContextDimmed             ColorKey = "contextDimmed"
+	OldDimmed                 ColorKey = "oldDimmed"
+	NewDimmed                 ColorKey = "newDimmed"
+	ContextBold               ColorKey = "contextBold"
+	OldBold                   ColorKey = "oldBold"
+	NewBold                   ColorKey = "newBold"
+)
+
+// A ColorConfig is a color configuration. A nil or empty ColorConfig
+// corresponds to no color.
+type ColorConfig map[ColorKey]string
+
+// A ColorConfigOption sets an option on a ColorConfig.
+type ColorConfigOption func(ColorConfig)
+
+// WithColor sets the color for key.
+func WithColor(key ColorKey, color string) ColorConfigOption {
+	return func(cc ColorConfig) {
+		cc[key] = color
+	}
+}
+
+// defaultColorConfig is the default color configuration. See
+// https://github.com/git/git/blob/v2.26.2/diff.c#L57-L81.
+var defaultColorConfig = ColorConfig{
+	Context:                   color.Normal,
+	Meta:                      color.Bold,
+	Frag:                      color.Cyan,
+	Old:                       color.Red,
+	New:                       color.Green,
+	Commit:                    color.Yellow,
+	Whitespace:                color.BgRed,
+	Func:                      color.Normal,
+	OldMoved:                  color.BoldMagenta,
+	OldMovedAlternative:       color.BoldBlue,
+	OldMovedDimmed:            color.Faint,
+	OldMovedAlternativeDimmed: color.FaintItalic,
+	NewMoved:                  color.BoldCyan,
+	NewMovedAlternative:       color.BoldYellow,
+	NewMovedDimmed:            color.Faint,
+	NewMovedAlternativeDimmed: color.FaintItalic,
+	ContextDimmed:             color.Faint,
+	OldDimmed:                 color.FaintRed,
+	NewDimmed:                 color.FaintGreen,
+	ContextBold:               color.Bold,
+	OldBold:                   color.BoldRed,
+	NewBold:                   color.BoldGreen,
+}
+
+// NewColorConfig returns a new ColorConfig.
+func NewColorConfig(options ...ColorConfigOption) ColorConfig {
+	cc := make(ColorConfig)
+	for key, value := range defaultColorConfig {
+		cc[key] = value
+	}
+	for _, option := range options {
+		option(cc)
+	}
+	return cc
+}
+
+// Reset returns the ANSI escape sequence to reset the color with key set from
+// cc. If no color was set then no reset is needed so it returns the empty
+// string.
+func (cc ColorConfig) Reset(key ColorKey) string {
+	if cc[key] == "" {
+		return ""
+	}
+	return color.Reset
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/diff/patch.go

@@ -0,0 +1,58 @@
+package diff
+
+import (
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/filemode"
+)
+
+// Operation defines the operation of a diff item.
+type Operation int
+
+const (
+	// Equal item represents an equals diff.
+	Equal Operation = iota
+	// Add item represents an insert diff.
+	Add
+	// Delete item represents a delete diff.
+	Delete
+)
+
+// Patch represents a collection of steps to transform several files.
+type Patch interface {
+	// FilePatches returns a slice of patches per file.
+	FilePatches() []FilePatch
+	// Message returns an optional message that can be at the top of the
+	// Patch representation.
+	Message() string
+}
+
+// FilePatch represents the necessary steps to transform one file into another.
+type FilePatch interface {
+	// IsBinary returns true if this patch is representing a binary file.
+	IsBinary() bool
+	// Files returns the from and to Files, with all the necessary metadata
+	// about them. If the patch creates a new file, "from" will be nil.
+	// If the patch deletes a file, "to" will be nil.
+	Files() (from, to File)
+	// Chunks returns a slice of ordered changes to transform "from" File into
+	// "to" File. If the file is a binary one, Chunks will be empty.
+	Chunks() []Chunk
+}
+
+// File contains all the file metadata necessary to print some patch formats.
+type File interface {
+	// Hash returns the File Hash.
+	Hash() plumbing.Hash
+	// Mode returns the FileMode.
+	Mode() filemode.FileMode
+	// Path returns the complete Path to the file, including the filename.
+	Path() string
+}
+
+// Chunk represents a portion of a file transformation into another.
+type Chunk interface {
+	// Content contains the portion of the file.
+	Content() string
+	// Type contains the Operation to do with this Chunk.
+	Type() Operation
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/diff/unified_encoder.go

@@ -0,0 +1,395 @@
+package diff
+
+import (
+	"fmt"
+	"io"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/go-git/go-git/v5/plumbing"
+)
+
+// DefaultContextLines is the default number of context lines.
+const DefaultContextLines = 3
+
+var (
+	splitLinesRegexp = regexp.MustCompile(`[^\n]*(\n|$)`)
+
+	operationChar = map[Operation]byte{
+		Add:    '+',
+		Delete: '-',
+		Equal:  ' ',
+	}
+
+	operationColorKey = map[Operation]ColorKey{
+		Add:    New,
+		Delete: Old,
+		Equal:  Context,
+	}
+)
+
+// UnifiedEncoder encodes an unified diff into the provided Writer. It does not
+// support similarity index for renames or sorting hash representations.
+type UnifiedEncoder struct {
+	io.Writer
+
+	// contextLines is the count of unchanged lines that will appear surrounding
+	// a change.
+	contextLines int
+
+	// srcPrefix and dstPrefix are prepended to file paths when encoding a diff.
+	srcPrefix string
+	dstPrefix string
+
+	// colorConfig is the color configuration. The default is no color.
+	color ColorConfig
+}
+
+// NewUnifiedEncoder returns a new UnifiedEncoder that writes to w.
+func NewUnifiedEncoder(w io.Writer, contextLines int) *UnifiedEncoder {
+	return &UnifiedEncoder{
+		Writer:       w,
+		srcPrefix:    "a/",
+		dstPrefix:    "b/",
+		contextLines: contextLines,
+	}
+}
+
+// SetColor sets e's color configuration and returns e.
+func (e *UnifiedEncoder) SetColor(colorConfig ColorConfig) *UnifiedEncoder {
+	e.color = colorConfig
+	return e
+}
+
+// SetSrcPrefix sets e's srcPrefix and returns e.
+func (e *UnifiedEncoder) SetSrcPrefix(prefix string) *UnifiedEncoder {
+	e.srcPrefix = prefix
+	return e
+}
+
+// SetDstPrefix sets e's dstPrefix and returns e.
+func (e *UnifiedEncoder) SetDstPrefix(prefix string) *UnifiedEncoder {
+	e.dstPrefix = prefix
+	return e
+}
+
+// Encode encodes patch.
+func (e *UnifiedEncoder) Encode(patch Patch) error {
+	sb := &strings.Builder{}
+
+	if message := patch.Message(); message != "" {
+		sb.WriteString(message)
+		if !strings.HasSuffix(message, "\n") {
+			sb.WriteByte('\n')
+		}
+	}
+
+	for _, filePatch := range patch.FilePatches() {
+		e.writeFilePatchHeader(sb, filePatch)
+		g := newHunksGenerator(filePatch.Chunks(), e.contextLines)
+		for _, hunk := range g.Generate() {
+			hunk.writeTo(sb, e.color)
+		}
+	}
+
+	_, err := e.Write([]byte(sb.String()))
+	return err
+}
+
+func (e *UnifiedEncoder) writeFilePatchHeader(sb *strings.Builder, filePatch FilePatch) {
+	from, to := filePatch.Files()
+	if from == nil && to == nil {
+		return
+	}
+	isBinary := filePatch.IsBinary()
+
+	var lines []string
+	switch {
+	case from != nil && to != nil:
+		hashEquals := from.Hash() == to.Hash()
+		lines = append(lines,
+			fmt.Sprintf("diff --git %s%s %s%s",
+				e.srcPrefix, from.Path(), e.dstPrefix, to.Path()),
+		)
+		if from.Mode() != to.Mode() {
+			lines = append(lines,
+				fmt.Sprintf("old mode %o", from.Mode()),
+				fmt.Sprintf("new mode %o", to.Mode()),
+			)
+		}
+		if from.Path() != to.Path() {
+			lines = append(lines,
+				fmt.Sprintf("rename from %s", from.Path()),
+				fmt.Sprintf("rename to %s", to.Path()),
+			)
+		}
+		if from.Mode() != to.Mode() && !hashEquals {
+			lines = append(lines,
+				fmt.Sprintf("index %s..%s", from.Hash(), to.Hash()),
+			)
+		} else if !hashEquals {
+			lines = append(lines,
+				fmt.Sprintf("index %s..%s %o", from.Hash(), to.Hash(), from.Mode()),
+			)
+		}
+		if !hashEquals {
+			lines = e.appendPathLines(lines, e.srcPrefix+from.Path(), e.dstPrefix+to.Path(), isBinary)
+		}
+	case from == nil:
+		lines = append(lines,
+			fmt.Sprintf("diff --git %s %s", e.srcPrefix+to.Path(), e.dstPrefix+to.Path()),
+			fmt.Sprintf("new file mode %o", to.Mode()),
+			fmt.Sprintf("index %s..%s", plumbing.ZeroHash, to.Hash()),
+		)
+		lines = e.appendPathLines(lines, "/dev/null", e.dstPrefix+to.Path(), isBinary)
+	case to == nil:
+		lines = append(lines,
+			fmt.Sprintf("diff --git %s %s", e.srcPrefix+from.Path(), e.dstPrefix+from.Path()),
+			fmt.Sprintf("deleted file mode %o", from.Mode()),
+			fmt.Sprintf("index %s..%s", from.Hash(), plumbing.ZeroHash),
+		)
+		lines = e.appendPathLines(lines, e.srcPrefix+from.Path(), "/dev/null", isBinary)
+	}
+
+	sb.WriteString(e.color[Meta])
+	sb.WriteString(lines[0])
+	for _, line := range lines[1:] {
+		sb.WriteByte('\n')
+		sb.WriteString(line)
+	}
+	sb.WriteString(e.color.Reset(Meta))
+	sb.WriteByte('\n')
+}
+
+func (e *UnifiedEncoder) appendPathLines(lines []string, fromPath, toPath string, isBinary bool) []string {
+	if isBinary {
+		return append(lines,
+			fmt.Sprintf("Binary files %s and %s differ", fromPath, toPath),
+		)
+	}
+	return append(lines,
+		fmt.Sprintf("--- %s", fromPath),
+		fmt.Sprintf("+++ %s", toPath),
+	)
+}
+
+type hunksGenerator struct {
+	fromLine, toLine            int
+	ctxLines                    int
+	chunks                      []Chunk
+	current                     *hunk
+	hunks                       []*hunk
+	beforeContext, afterContext []string
+}
+
+func newHunksGenerator(chunks []Chunk, ctxLines int) *hunksGenerator {
+	return &hunksGenerator{
+		chunks:   chunks,
+		ctxLines: ctxLines,
+	}
+}
+
+func (g *hunksGenerator) Generate() []*hunk {
+	for i, chunk := range g.chunks {
+		lines := splitLines(chunk.Content())
+		nLines := len(lines)
+
+		switch chunk.Type() {
+		case Equal:
+			g.fromLine += nLines
+			g.toLine += nLines
+			g.processEqualsLines(lines, i)
+		case Delete:
+			if nLines != 0 {
+				g.fromLine++
+			}
+
+			g.processHunk(i, chunk.Type())
+			g.fromLine += nLines - 1
+			g.current.AddOp(chunk.Type(), lines...)
+		case Add:
+			if nLines != 0 {
+				g.toLine++
+			}
+			g.processHunk(i, chunk.Type())
+			g.toLine += nLines - 1
+			g.current.AddOp(chunk.Type(), lines...)
+		}
+
+		if i == len(g.chunks)-1 && g.current != nil {
+			g.hunks = append(g.hunks, g.current)
+		}
+	}
+
+	return g.hunks
+}
+
+func (g *hunksGenerator) processHunk(i int, op Operation) {
+	if g.current != nil {
+		return
+	}
+
+	var ctxPrefix string
+	linesBefore := len(g.beforeContext)
+	if linesBefore > g.ctxLines {
+		ctxPrefix = g.beforeContext[linesBefore-g.ctxLines-1]
+		g.beforeContext = g.beforeContext[linesBefore-g.ctxLines:]
+		linesBefore = g.ctxLines
+	}
+
+	g.current = &hunk{ctxPrefix: strings.TrimSuffix(ctxPrefix, "\n")}
+	g.current.AddOp(Equal, g.beforeContext...)
+
+	switch op {
+	case Delete:
+		g.current.fromLine, g.current.toLine =
+			g.addLineNumbers(g.fromLine, g.toLine, linesBefore, i, Add)
+	case Add:
+		g.current.toLine, g.current.fromLine =
+			g.addLineNumbers(g.toLine, g.fromLine, linesBefore, i, Delete)
+	}
+
+	g.beforeContext = nil
+}
+
+// addLineNumbers obtains the line numbers in a new chunk.
+func (g *hunksGenerator) addLineNumbers(la, lb int, linesBefore int, i int, op Operation) (cla, clb int) {
+	cla = la - linesBefore
+	// we need to search for a reference for the next diff
+	switch {
+	case linesBefore != 0 && g.ctxLines != 0:
+		if lb > g.ctxLines {
+			clb = lb - g.ctxLines + 1
+		} else {
+			clb = 1
+		}
+	case g.ctxLines == 0:
+		clb = lb
+	case i != len(g.chunks)-1:
+		next := g.chunks[i+1]
+		if next.Type() == op || next.Type() == Equal {
+			// this diff will be into this chunk
+			clb = lb + 1
+		}
+	}
+
+	return
+}
+
+func (g *hunksGenerator) processEqualsLines(ls []string, i int) {
+	if g.current == nil {
+		g.beforeContext = append(g.beforeContext, ls...)
+		return
+	}
+
+	g.afterContext = append(g.afterContext, ls...)
+	if len(g.afterContext) <= g.ctxLines*2 && i != len(g.chunks)-1 {
+		g.current.AddOp(Equal, g.afterContext...)
+		g.afterContext = nil
+	} else {
+		ctxLines := g.ctxLines
+		if ctxLines > len(g.afterContext) {
+			ctxLines = len(g.afterContext)
+		}
+		g.current.AddOp(Equal, g.afterContext[:ctxLines]...)
+		g.hunks = append(g.hunks, g.current)
+
+		g.current = nil
+		g.beforeContext = g.afterContext[ctxLines:]
+		g.afterContext = nil
+	}
+}
+
+func splitLines(s string) []string {
+	out := splitLinesRegexp.FindAllString(s, -1)
+	if out[len(out)-1] == "" {
+		out = out[:len(out)-1]
+	}
+	return out
+}
+
+type hunk struct {
+	fromLine int
+	toLine   int
+
+	fromCount int
+	toCount   int
+
+	ctxPrefix string
+	ops       []*op
+}
+
+func (h *hunk) writeTo(sb *strings.Builder, color ColorConfig) {
+	sb.WriteString(color[Frag])
+	sb.WriteString("@@ -")
+
+	if h.fromCount == 1 {
+		sb.WriteString(strconv.Itoa(h.fromLine))
+	} else {
+		sb.WriteString(strconv.Itoa(h.fromLine))
+		sb.WriteByte(',')
+		sb.WriteString(strconv.Itoa(h.fromCount))
+	}
+
+	sb.WriteString(" +")
+
+	if h.toCount == 1 {
+		sb.WriteString(strconv.Itoa(h.toLine))
+	} else {
+		sb.WriteString(strconv.Itoa(h.toLine))
+		sb.WriteByte(',')
+		sb.WriteString(strconv.Itoa(h.toCount))
+	}
+
+	sb.WriteString(" @@")
+	sb.WriteString(color.Reset(Frag))
+
+	if h.ctxPrefix != "" {
+		sb.WriteByte(' ')
+		sb.WriteString(color[Func])
+		sb.WriteString(h.ctxPrefix)
+		sb.WriteString(color.Reset(Func))
+	}
+
+	sb.WriteByte('\n')
+
+	for _, op := range h.ops {
+		op.writeTo(sb, color)
+	}
+}
+
+func (h *hunk) AddOp(t Operation, ss ...string) {
+	n := len(ss)
+	switch t {
+	case Add:
+		h.toCount += n
+	case Delete:
+		h.fromCount += n
+	case Equal:
+		h.toCount += n
+		h.fromCount += n
+	}
+
+	for _, s := range ss {
+		h.ops = append(h.ops, &op{s, t})
+	}
+}
+
+type op struct {
+	text string
+	t    Operation
+}
+
+func (o *op) writeTo(sb *strings.Builder, color ColorConfig) {
+	colorKey := operationColorKey[o.t]
+	sb.WriteString(color[colorKey])
+	sb.WriteByte(operationChar[o.t])
+	if strings.HasSuffix(o.text, "\n") {
+		sb.WriteString(strings.TrimSuffix(o.text, "\n"))
+	} else {
+		sb.WriteString(o.text + "\n\\ No newline at end of file")
+	}
+	sb.WriteString(color.Reset(colorKey))
+	sb.WriteByte('\n')
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/gitignore/dir.go

@@ -0,0 +1,144 @@
+package gitignore
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/go-git/go-billy/v5"
+	"github.com/go-git/go-git/v5/internal/path_util"
+	"github.com/go-git/go-git/v5/plumbing/format/config"
+	gioutil "github.com/go-git/go-git/v5/utils/ioutil"
+)
+
+const (
+	commentPrefix   = "#"
+	coreSection     = "core"
+	excludesfile    = "excludesfile"
+	gitDir          = ".git"
+	gitignoreFile   = ".gitignore"
+	gitconfigFile   = ".gitconfig"
+	systemFile      = "/etc/gitconfig"
+	infoExcludeFile = gitDir + "/info/exclude"
+)
+
+// readIgnoreFile reads a specific git ignore file.
+func readIgnoreFile(fs billy.Filesystem, path []string, ignoreFile string) (ps []Pattern, err error) {
+
+	ignoreFile, _ = path_util.ReplaceTildeWithHome(ignoreFile)
+
+	f, err := fs.Open(fs.Join(append(path, ignoreFile)...))
+	if err == nil {
+		defer f.Close()
+
+		scanner := bufio.NewScanner(f)
+		for scanner.Scan() {
+			s := scanner.Text()
+			if !strings.HasPrefix(s, commentPrefix) && len(strings.TrimSpace(s)) > 0 {
+				ps = append(ps, ParsePattern(s, path))
+			}
+		}
+	} else if !os.IsNotExist(err) {
+		return nil, err
+	}
+
+	return
+}
+
+// ReadPatterns reads the .git/info/exclude and then the gitignore patterns
+// recursively traversing through the directory structure. The result is in
+// the ascending order of priority (last higher).
+func ReadPatterns(fs billy.Filesystem, path []string) (ps []Pattern, err error) {
+	ps, _ = readIgnoreFile(fs, path, infoExcludeFile)
+
+	subps, _ := readIgnoreFile(fs, path, gitignoreFile)
+	ps = append(ps, subps...)
+
+	var fis []os.FileInfo
+	fis, err = fs.ReadDir(fs.Join(path...))
+	if err != nil {
+		return
+	}
+
+	for _, fi := range fis {
+		if fi.IsDir() && fi.Name() != gitDir {
+			var subps []Pattern
+			subps, err = ReadPatterns(fs, append(path, fi.Name()))
+			if err != nil {
+				return
+			}
+
+			if len(subps) > 0 {
+				ps = append(ps, subps...)
+			}
+		}
+	}
+
+	return
+}
+
+func loadPatterns(fs billy.Filesystem, path string) (ps []Pattern, err error) {
+	f, err := fs.Open(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	defer gioutil.CheckClose(f, &err)
+
+	b, err := io.ReadAll(f)
+	if err != nil {
+		return
+	}
+
+	d := config.NewDecoder(bytes.NewBuffer(b))
+
+	raw := config.New()
+	if err = d.Decode(raw); err != nil {
+		return
+	}
+
+	s := raw.Section(coreSection)
+	efo := s.Options.Get(excludesfile)
+	if efo == "" {
+		return nil, nil
+	}
+
+	ps, err = readIgnoreFile(fs, nil, efo)
+	if os.IsNotExist(err) {
+		return nil, nil
+	}
+
+	return
+}
+
+// LoadGlobalPatterns loads gitignore patterns from the gitignore file
+// declared in a user's ~/.gitconfig file.  If the ~/.gitconfig file does not
+// exist the function will return nil.  If the core.excludesfile property
+// is not declared, the function will return nil.  If the file pointed to by
+// the core.excludesfile property does not exist, the function will return nil.
+//
+// The function assumes fs is rooted at the root filesystem.
+func LoadGlobalPatterns(fs billy.Filesystem) (ps []Pattern, err error) {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return
+	}
+
+	return loadPatterns(fs, fs.Join(home, gitconfigFile))
+}
+
+// LoadSystemPatterns loads gitignore patterns from the gitignore file
+// declared in a system's /etc/gitconfig file.  If the /etc/gitconfig file does
+// not exist the function will return nil.  If the core.excludesfile property
+// is not declared, the function will return nil.  If the file pointed to by
+// the core.excludesfile property does not exist, the function will return nil.
+//
+// The function assumes fs is rooted at the root filesystem.
+func LoadSystemPatterns(fs billy.Filesystem) (ps []Pattern, err error) {
+	return loadPatterns(fs, systemFile)
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/gitignore/doc.go

@@ -0,0 +1,70 @@
+// Package gitignore implements matching file system paths to gitignore patterns that
+// can be automatically read from a git repository tree in the order of definition
+// priorities. It support all pattern formats as specified in the original gitignore
+// documentation, copied below:
+//
+//	  Pattern format
+//	  ==============
+//
+//			- A blank line matches no files, so it can serve as a separator for readability.
+//
+//			- A line starting with # serves as a comment. Put a backslash ("\") in front of
+//			  the first hash for patterns that begin with a hash.
+//
+//			- Trailing spaces are ignored unless they are quoted with backslash ("\").
+//
+//			- An optional prefix "!" which negates the pattern; any matching file excluded
+//			  by a previous pattern will become included again. It is not possible to
+//			  re-include a file if a parent directory of that file is excluded.
+//			  Git doesn’t list excluded directories for performance reasons, so
+//			  any patterns on contained files have no effect, no matter where they are
+//			  defined. Put a backslash ("\") in front of the first "!" for patterns
+//			  that begin with a literal "!", for example, "\!important!.txt".
+//
+//			- If the pattern ends with a slash, it is removed for the purpose of the
+//			  following description, but it would only find a match with a directory.
+//			  In other words, foo/ will match a directory foo and paths underneath it,
+//			  but will not match a regular file or a symbolic link foo (this is consistent
+//			  with the way how pathspec works in general in Git).
+//
+//			- If the pattern does not contain a slash /, Git treats it as a shell glob
+//			  pattern and checks for a match against the pathname relative to the location
+//			  of the .gitignore file (relative to the toplevel of the work tree if not
+//			  from a .gitignore file).
+//
+//			- Otherwise, Git treats the pattern as a shell glob suitable for consumption
+//			  by fnmatch(3) with the FNM_PATHNAME flag: wildcards in the pattern will
+//			  not match a / in the pathname. For example, "Documentation/*.html" matches
+//			  "Documentation/git.html" but not "Documentation/ppc/ppc.html" or
+//			  "tools/perf/Documentation/perf.html".
+//
+//			- A leading slash matches the beginning of the pathname. For example,
+//			  "/*.c" matches "cat-file.c" but not "mozilla-sha1/sha1.c".
+//
+//			Two consecutive asterisks ("**") in patterns matched against full pathname
+//			may have special meaning:
+//
+//			- A leading "**" followed by a slash means match in all directories.
+//			  For example, "**/foo" matches file or directory "foo" anywhere, the same as
+//			  pattern "foo". "**/foo/bar" matches file or directory "bar"
+//			  anywhere that is directly under directory "foo".
+//
+//			- A trailing "/**" matches everything inside. For example, "abc/**" matches
+//			  all files inside directory "abc", relative to the location of the
+//			  .gitignore file, with infinite depth.
+//
+//			- A slash followed by two consecutive asterisks then a slash matches
+//			  zero or more directories. For example, "a/**/b" matches "a/b", "a/x/b",
+//			  "a/x/y/b" and so on.
+//
+//			- Other consecutive asterisks are considered invalid.
+//
+//	  Copyright and license
+//	  =====================
+//
+//			Copyright (c) Oleg Sklyar, Silvertern and source{d}
+//
+//			The package code was donated to source{d} to include, modify and develop
+//			further as a part of the `go-git` project, release it on the license of
+//			the whole project or delete it from the project.
+package gitignore

vendor/github.com/go-git/go-git/v5/plumbing/format/gitignore/matcher.go

@@ -0,0 +1,30 @@
+package gitignore
+
+// Matcher defines a global multi-pattern matcher for gitignore patterns
+type Matcher interface {
+	// Match matches patterns in the order of priorities. As soon as an inclusion or
+	// exclusion is found, not further matching is performed.
+	Match(path []string, isDir bool) bool
+}
+
+// NewMatcher constructs a new global matcher. Patterns must be given in the order of
+// increasing priority. That is most generic settings files first, then the content of
+// the repo .gitignore, then content of .gitignore down the path or the repo and then
+// the content command line arguments.
+func NewMatcher(ps []Pattern) Matcher {
+	return &matcher{ps}
+}
+
+type matcher struct {
+	patterns []Pattern
+}
+
+func (m *matcher) Match(path []string, isDir bool) bool {
+	n := len(m.patterns)
+	for i := n - 1; i >= 0; i-- {
+		if match := m.patterns[i].Match(path, isDir); match > NoMatch {
+			return match == Exclude
+		}
+	}
+	return false
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/gitignore/pattern.go

@@ -0,0 +1,155 @@
+package gitignore
+
+import (
+	"path/filepath"
+	"strings"
+)
+
+// MatchResult defines outcomes of a match, no match, exclusion or inclusion.
+type MatchResult int
+
+const (
+	// NoMatch defines the no match outcome of a match check
+	NoMatch MatchResult = iota
+	// Exclude defines an exclusion of a file as a result of a match check
+	Exclude
+	// Include defines an explicit inclusion of a file as a result of a match check
+	Include
+)
+
+const (
+	inclusionPrefix = "!"
+	zeroToManyDirs  = "**"
+	patternDirSep   = "/"
+)
+
+// Pattern defines a single gitignore pattern.
+type Pattern interface {
+	// Match matches the given path to the pattern.
+	Match(path []string, isDir bool) MatchResult
+}
+
+type pattern struct {
+	domain    []string
+	pattern   []string
+	inclusion bool
+	dirOnly   bool
+	isGlob    bool
+}
+
+// ParsePattern parses a gitignore pattern string into the Pattern structure.
+func ParsePattern(p string, domain []string) Pattern {
+	// storing domain, copy it to ensure it isn't changed externally
+	domain = append([]string(nil), domain...)
+	res := pattern{domain: domain}
+
+	if strings.HasPrefix(p, inclusionPrefix) {
+		res.inclusion = true
+		p = p[1:]
+	}
+
+	if !strings.HasSuffix(p, "\\ ") {
+		p = strings.TrimRight(p, " ")
+	}
+
+	if strings.HasSuffix(p, patternDirSep) {
+		res.dirOnly = true
+		p = p[:len(p)-1]
+	}
+
+	if strings.Contains(p, patternDirSep) {
+		res.isGlob = true
+	}
+
+	res.pattern = strings.Split(p, patternDirSep)
+	return &res
+}
+
+func (p *pattern) Match(path []string, isDir bool) MatchResult {
+	if len(path) <= len(p.domain) {
+		return NoMatch
+	}
+	for i, e := range p.domain {
+		if path[i] != e {
+			return NoMatch
+		}
+	}
+
+	path = path[len(p.domain):]
+	if p.isGlob && !p.globMatch(path, isDir) {
+		return NoMatch
+	} else if !p.isGlob && !p.simpleNameMatch(path, isDir) {
+		return NoMatch
+	}
+
+	if p.inclusion {
+		return Include
+	} else {
+		return Exclude
+	}
+}
+
+func (p *pattern) simpleNameMatch(path []string, isDir bool) bool {
+	for i, name := range path {
+		if match, err := filepath.Match(p.pattern[0], name); err != nil {
+			return false
+		} else if !match {
+			continue
+		}
+		if p.dirOnly && !isDir && i == len(path)-1 {
+			return false
+		}
+		return true
+	}
+	return false
+}
+
+func (p *pattern) globMatch(path []string, isDir bool) bool {
+	matched := false
+	canTraverse := false
+	for i, pattern := range p.pattern {
+		if pattern == "" {
+			canTraverse = false
+			continue
+		}
+		if pattern == zeroToManyDirs {
+			if i == len(p.pattern)-1 {
+				break
+			}
+			canTraverse = true
+			continue
+		}
+		if strings.Contains(pattern, zeroToManyDirs) {
+			return false
+		}
+		if len(path) == 0 {
+			return false
+		}
+		if canTraverse {
+			canTraverse = false
+			for len(path) > 0 {
+				e := path[0]
+				path = path[1:]
+				if match, err := filepath.Match(pattern, e); err != nil {
+					return false
+				} else if match {
+					matched = true
+					break
+				} else if len(path) == 0 {
+					// if nothing left then fail
+					matched = false
+				}
+			}
+		} else {
+			if match, err := filepath.Match(pattern, path[0]); err != nil || !match {
+				return false
+			}
+			matched = true
+			path = path[1:]
+		}
+	}
+	if matched && p.dirOnly && !isDir && len(path) == 0 {
+		matched = false
+	}
+	return matched
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/idxfile/decoder.go

@@ -0,0 +1,178 @@
+package idxfile
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"io"
+
+	"github.com/go-git/go-git/v5/plumbing/hash"
+	"github.com/go-git/go-git/v5/utils/binary"
+)
+
+var (
+	// ErrUnsupportedVersion is returned by Decode when the idx file version
+	// is not supported.
+	ErrUnsupportedVersion = errors.New("unsupported version")
+	// ErrMalformedIdxFile is returned by Decode when the idx file is corrupted.
+	ErrMalformedIdxFile = errors.New("malformed IDX file")
+)
+
+const (
+	fanout         = 256
+	objectIDLength = hash.Size
+)
+
+// Decoder reads and decodes idx files from an input stream.
+type Decoder struct {
+	*bufio.Reader
+}
+
+// NewDecoder builds a new idx stream decoder, that reads from r.
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{bufio.NewReader(r)}
+}
+
+// Decode reads from the stream and decode the content into the MemoryIndex struct.
+func (d *Decoder) Decode(idx *MemoryIndex) error {
+	if err := validateHeader(d); err != nil {
+		return err
+	}
+
+	flow := []func(*MemoryIndex, io.Reader) error{
+		readVersion,
+		readFanout,
+		readObjectNames,
+		readCRC32,
+		readOffsets,
+		readChecksums,
+	}
+
+	for _, f := range flow {
+		if err := f(idx, d); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func validateHeader(r io.Reader) error {
+	var h = make([]byte, 4)
+	if _, err := io.ReadFull(r, h); err != nil {
+		return err
+	}
+
+	if !bytes.Equal(h, idxHeader) {
+		return ErrMalformedIdxFile
+	}
+
+	return nil
+}
+
+func readVersion(idx *MemoryIndex, r io.Reader) error {
+	v, err := binary.ReadUint32(r)
+	if err != nil {
+		return err
+	}
+
+	if v > VersionSupported {
+		return ErrUnsupportedVersion
+	}
+
+	idx.Version = v
+	return nil
+}
+
+func readFanout(idx *MemoryIndex, r io.Reader) error {
+	for k := 0; k < fanout; k++ {
+		n, err := binary.ReadUint32(r)
+		if err != nil {
+			return err
+		}
+
+		idx.Fanout[k] = n
+		idx.FanoutMapping[k] = noMapping
+	}
+
+	return nil
+}
+
+func readObjectNames(idx *MemoryIndex, r io.Reader) error {
+	for k := 0; k < fanout; k++ {
+		var buckets uint32
+		if k == 0 {
+			buckets = idx.Fanout[k]
+		} else {
+			buckets = idx.Fanout[k] - idx.Fanout[k-1]
+		}
+
+		if buckets == 0 {
+			continue
+		}
+
+		idx.FanoutMapping[k] = len(idx.Names)
+
+		nameLen := int(buckets * objectIDLength)
+		bin := make([]byte, nameLen)
+		if _, err := io.ReadFull(r, bin); err != nil {
+			return err
+		}
+
+		idx.Names = append(idx.Names, bin)
+		idx.Offset32 = append(idx.Offset32, make([]byte, buckets*4))
+		idx.CRC32 = append(idx.CRC32, make([]byte, buckets*4))
+	}
+
+	return nil
+}
+
+func readCRC32(idx *MemoryIndex, r io.Reader) error {
+	for k := 0; k < fanout; k++ {
+		if pos := idx.FanoutMapping[k]; pos != noMapping {
+			if _, err := io.ReadFull(r, idx.CRC32[pos]); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func readOffsets(idx *MemoryIndex, r io.Reader) error {
+	var o64cnt int
+	for k := 0; k < fanout; k++ {
+		if pos := idx.FanoutMapping[k]; pos != noMapping {
+			if _, err := io.ReadFull(r, idx.Offset32[pos]); err != nil {
+				return err
+			}
+
+			for p := 0; p < len(idx.Offset32[pos]); p += 4 {
+				if idx.Offset32[pos][p]&(byte(1)<<7) > 0 {
+					o64cnt++
+				}
+			}
+		}
+	}
+
+	if o64cnt > 0 {
+		idx.Offset64 = make([]byte, o64cnt*8)
+		if _, err := io.ReadFull(r, idx.Offset64); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func readChecksums(idx *MemoryIndex, r io.Reader) error {
+	if _, err := io.ReadFull(r, idx.PackfileChecksum[:]); err != nil {
+		return err
+	}
+
+	if _, err := io.ReadFull(r, idx.IdxChecksum[:]); err != nil {
+		return err
+	}
+
+	return nil
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/idxfile/doc.go

@@ -0,0 +1,128 @@
+// Package idxfile implements encoding and decoding of packfile idx files.
+//
+//	== Original (version 1) pack-*.idx files have the following format:
+//
+//	  - The header consists of 256 4-byte network byte order
+//	    integers.  N-th entry of this table records the number of
+//	    objects in the corresponding pack, the first byte of whose
+//	    object name is less than or equal to N.  This is called the
+//	    'first-level fan-out' table.
+//
+//	  - The header is followed by sorted 24-byte entries, one entry
+//	    per object in the pack.  Each entry is:
+//
+//	   4-byte network byte order integer, recording where the
+//	   object is stored in the packfile as the offset from the
+//	   beginning.
+//
+//	   20-byte object name.
+//
+//	 - The file is concluded with a trailer:
+//
+//	   A copy of the 20-byte SHA1 checksum at the end of
+//	   corresponding packfile.
+//
+//	   20-byte SHA1-checksum of all of the above.
+//
+//	 Pack Idx file:
+//
+//	      --  +--------------------------------+
+//	 fanout   | fanout[0] = 2 (for example)    |-.
+//	 table    +--------------------------------+ |
+//	          | fanout[1]                      | |
+//	          +--------------------------------+ |
+//	          | fanout[2]                      | |
+//	          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
+//	          | fanout[255] = total objects    |---.
+//	      --  +--------------------------------+ | |
+//	 main     | offset                         | | |
+//	 index    | object name 00XXXXXXXXXXXXXXXX | | |
+//	 tab      +--------------------------------+ | |
+//	          | offset                         | | |
+//	          | object name 00XXXXXXXXXXXXXXXX | | |
+//	          +--------------------------------+<+ |
+//	        .-| offset                         |   |
+//	        | | object name 01XXXXXXXXXXXXXXXX |   |
+//	        | +--------------------------------+   |
+//	        | | offset                         |   |
+//	        | | object name 01XXXXXXXXXXXXXXXX |   |
+//	        | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~   |
+//	        | | offset                         |   |
+//	        | | object name FFXXXXXXXXXXXXXXXX |   |
+//	      --| +--------------------------------+<--+
+//	trailer | | packfile checksum              |
+//	        | +--------------------------------+
+//	        | | idxfile checksum               |
+//	        | +--------------------------------+
+//	        .---------.
+//	                  |
+//	Pack file entry: <+
+//
+//	   packed object header:
+//	   1-byte size extension bit (MSB)
+//	         type (next 3 bit)
+//	         size0 (lower 4-bit)
+//	       n-byte sizeN (as long as MSB is set, each 7-bit)
+//	       size0..sizeN form 4+7+7+..+7 bit integer, size0
+//	       is the least significant part, and sizeN is the
+//	       most significant part.
+//	   packed object data:
+//	       If it is not DELTA, then deflated bytes (the size above
+//	       is the size before compression).
+//	   If it is REF_DELTA, then
+//	     20-byte base object name SHA1 (the size above is the
+//	       size of the delta data that follows).
+//	         delta data, deflated.
+//	   If it is OFS_DELTA, then
+//	     n-byte offset (see below) interpreted as a negative
+//	       offset from the type-byte of the header of the
+//	       ofs-delta entry (the size above is the size of
+//	       the delta data that follows).
+//	     delta data, deflated.
+//
+//	   offset encoding:
+//	     n bytes with MSB set in all but the last one.
+//	     The offset is then the number constructed by
+//	     concatenating the lower 7 bit of each byte, and
+//	     for n >= 2 adding 2^7 + 2^14 + ... + 2^(7*(n-1))
+//	     to the result.
+//
+//	 == Version 2 pack-*.idx files support packs larger than 4 GiB, and
+//	    have some other reorganizations.  They have the format:
+//
+//	   - A 4-byte magic number '\377tOc' which is an unreasonable
+//	     fanout[0] value.
+//
+//	   - A 4-byte version number (= 2)
+//
+//	   - A 256-entry fan-out table just like v1.
+//
+//	   - A table of sorted 20-byte SHA1 object names.  These are
+//	     packed together without offset values to reduce the cache
+//	     footprint of the binary search for a specific object name.
+//
+//	   - A table of 4-byte CRC32 values of the packed object data.
+//	     This is new in v2 so compressed data can be copied directly
+//	     from pack to pack during repacking without undetected
+//	     data corruption.
+//
+//	   - A table of 4-byte offset values (in network byte order).
+//	     These are usually 31-bit pack file offsets, but large
+//	     offsets are encoded as an index into the next table with
+//	     the msbit set.
+//
+//	   - A table of 8-byte offset entries (empty for pack files less
+//	     than 2 GiB).  Pack files are organized with heavily used
+//	     objects toward the front, so most object references should
+//	     not need to refer to this table.
+//
+//	   - The same trailer as a v1 pack file:
+//
+//	     A copy of the 20-byte SHA1 checksum at the end of
+//	     corresponding packfile.
+//
+//	     20-byte SHA1-checksum of all of the above.
+//
+// Source:
+// https://www.kernel.org/pub/software/scm/git/docs/v1.7.5/technical/pack-format.txt
+package idxfile

vendor/github.com/go-git/go-git/v5/plumbing/format/idxfile/encoder.go

@@ -0,0 +1,141 @@
+package idxfile
+
+import (
+	"io"
+
+	"github.com/go-git/go-git/v5/plumbing/hash"
+	"github.com/go-git/go-git/v5/utils/binary"
+)
+
+// Encoder writes MemoryIndex structs to an output stream.
+type Encoder struct {
+	io.Writer
+	hash hash.Hash
+}
+
+// NewEncoder returns a new stream encoder that writes to w.
+func NewEncoder(w io.Writer) *Encoder {
+	h := hash.New(hash.CryptoType)
+	mw := io.MultiWriter(w, h)
+	return &Encoder{mw, h}
+}
+
+// Encode encodes an MemoryIndex to the encoder writer.
+func (e *Encoder) Encode(idx *MemoryIndex) (int, error) {
+	flow := []func(*MemoryIndex) (int, error){
+		e.encodeHeader,
+		e.encodeFanout,
+		e.encodeHashes,
+		e.encodeCRC32,
+		e.encodeOffsets,
+		e.encodeChecksums,
+	}
+
+	sz := 0
+	for _, f := range flow {
+		i, err := f(idx)
+		sz += i
+
+		if err != nil {
+			return sz, err
+		}
+	}
+
+	return sz, nil
+}
+
+func (e *Encoder) encodeHeader(idx *MemoryIndex) (int, error) {
+	c, err := e.Write(idxHeader)
+	if err != nil {
+		return c, err
+	}
+
+	return c + 4, binary.WriteUint32(e, idx.Version)
+}
+
+func (e *Encoder) encodeFanout(idx *MemoryIndex) (int, error) {
+	for _, c := range idx.Fanout {
+		if err := binary.WriteUint32(e, c); err != nil {
+			return 0, err
+		}
+	}
+
+	return fanout * 4, nil
+}
+
+func (e *Encoder) encodeHashes(idx *MemoryIndex) (int, error) {
+	var size int
+	for k := 0; k < fanout; k++ {
+		pos := idx.FanoutMapping[k]
+		if pos == noMapping {
+			continue
+		}
+
+		n, err := e.Write(idx.Names[pos])
+		if err != nil {
+			return size, err
+		}
+		size += n
+	}
+	return size, nil
+}
+
+func (e *Encoder) encodeCRC32(idx *MemoryIndex) (int, error) {
+	var size int
+	for k := 0; k < fanout; k++ {
+		pos := idx.FanoutMapping[k]
+		if pos == noMapping {
+			continue
+		}
+
+		n, err := e.Write(idx.CRC32[pos])
+		if err != nil {
+			return size, err
+		}
+
+		size += n
+	}
+
+	return size, nil
+}
+
+func (e *Encoder) encodeOffsets(idx *MemoryIndex) (int, error) {
+	var size int
+	for k := 0; k < fanout; k++ {
+		pos := idx.FanoutMapping[k]
+		if pos == noMapping {
+			continue
+		}
+
+		n, err := e.Write(idx.Offset32[pos])
+		if err != nil {
+			return size, err
+		}
+
+		size += n
+	}
+
+	if len(idx.Offset64) > 0 {
+		n, err := e.Write(idx.Offset64)
+		if err != nil {
+			return size, err
+		}
+
+		size += n
+	}
+
+	return size, nil
+}
+
+func (e *Encoder) encodeChecksums(idx *MemoryIndex) (int, error) {
+	if _, err := e.Write(idx.PackfileChecksum[:]); err != nil {
+		return 0, err
+	}
+
+	copy(idx.IdxChecksum[:], e.hash.Sum(nil)[:hash.Size])
+	if _, err := e.Write(idx.IdxChecksum[:]); err != nil {
+		return 0, err
+	}
+
+	return hash.HexSize, nil
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/idxfile/idxfile.go

@@ -0,0 +1,347 @@
+package idxfile
+
+import (
+	"bytes"
+	"io"
+	"sort"
+
+	encbin "encoding/binary"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/hash"
+)
+
+const (
+	// VersionSupported is the only idx version supported.
+	VersionSupported = 2
+
+	noMapping = -1
+)
+
+var (
+	idxHeader = []byte{255, 't', 'O', 'c'}
+)
+
+// Index represents an index of a packfile.
+type Index interface {
+	// Contains checks whether the given hash is in the index.
+	Contains(h plumbing.Hash) (bool, error)
+	// FindOffset finds the offset in the packfile for the object with
+	// the given hash.
+	FindOffset(h plumbing.Hash) (int64, error)
+	// FindCRC32 finds the CRC32 of the object with the given hash.
+	FindCRC32(h plumbing.Hash) (uint32, error)
+	// FindHash finds the hash for the object with the given offset.
+	FindHash(o int64) (plumbing.Hash, error)
+	// Count returns the number of entries in the index.
+	Count() (int64, error)
+	// Entries returns an iterator to retrieve all index entries.
+	Entries() (EntryIter, error)
+	// EntriesByOffset returns an iterator to retrieve all index entries ordered
+	// by offset.
+	EntriesByOffset() (EntryIter, error)
+}
+
+// MemoryIndex is the in memory representation of an idx file.
+type MemoryIndex struct {
+	Version uint32
+	Fanout  [256]uint32
+	// FanoutMapping maps the position in the fanout table to the position
+	// in the Names, Offset32 and CRC32 slices. This improves the memory
+	// usage by not needing an array with unnecessary empty slots.
+	FanoutMapping    [256]int
+	Names            [][]byte
+	Offset32         [][]byte
+	CRC32            [][]byte
+	Offset64         []byte
+	PackfileChecksum [hash.Size]byte
+	IdxChecksum      [hash.Size]byte
+
+	offsetHash       map[int64]plumbing.Hash
+	offsetHashIsFull bool
+}
+
+var _ Index = (*MemoryIndex)(nil)
+
+// NewMemoryIndex returns an instance of a new MemoryIndex.
+func NewMemoryIndex() *MemoryIndex {
+	return &MemoryIndex{}
+}
+
+func (idx *MemoryIndex) findHashIndex(h plumbing.Hash) (int, bool) {
+	k := idx.FanoutMapping[h[0]]
+	if k == noMapping {
+		return 0, false
+	}
+
+	if len(idx.Names) <= k {
+		return 0, false
+	}
+
+	data := idx.Names[k]
+	high := uint64(len(idx.Offset32[k])) >> 2
+	if high == 0 {
+		return 0, false
+	}
+
+	low := uint64(0)
+	for {
+		mid := (low + high) >> 1
+		offset := mid * objectIDLength
+
+		cmp := bytes.Compare(h[:], data[offset:offset+objectIDLength])
+		if cmp < 0 {
+			high = mid
+		} else if cmp == 0 {
+			return int(mid), true
+		} else {
+			low = mid + 1
+		}
+
+		if low >= high {
+			break
+		}
+	}
+
+	return 0, false
+}
+
+// Contains implements the Index interface.
+func (idx *MemoryIndex) Contains(h plumbing.Hash) (bool, error) {
+	_, ok := idx.findHashIndex(h)
+	return ok, nil
+}
+
+// FindOffset implements the Index interface.
+func (idx *MemoryIndex) FindOffset(h plumbing.Hash) (int64, error) {
+	if len(idx.FanoutMapping) <= int(h[0]) {
+		return 0, plumbing.ErrObjectNotFound
+	}
+
+	k := idx.FanoutMapping[h[0]]
+	i, ok := idx.findHashIndex(h)
+	if !ok {
+		return 0, plumbing.ErrObjectNotFound
+	}
+
+	offset := idx.getOffset(k, i)
+
+	if !idx.offsetHashIsFull {
+		// Save the offset for reverse lookup
+		if idx.offsetHash == nil {
+			idx.offsetHash = make(map[int64]plumbing.Hash)
+		}
+		idx.offsetHash[int64(offset)] = h
+	}
+
+	return int64(offset), nil
+}
+
+const isO64Mask = uint64(1) << 31
+
+func (idx *MemoryIndex) getOffset(firstLevel, secondLevel int) uint64 {
+	offset := secondLevel << 2
+	ofs := encbin.BigEndian.Uint32(idx.Offset32[firstLevel][offset : offset+4])
+
+	if (uint64(ofs) & isO64Mask) != 0 {
+		offset := 8 * (uint64(ofs) & ^isO64Mask)
+		n := encbin.BigEndian.Uint64(idx.Offset64[offset : offset+8])
+		return n
+	}
+
+	return uint64(ofs)
+}
+
+// FindCRC32 implements the Index interface.
+func (idx *MemoryIndex) FindCRC32(h plumbing.Hash) (uint32, error) {
+	k := idx.FanoutMapping[h[0]]
+	i, ok := idx.findHashIndex(h)
+	if !ok {
+		return 0, plumbing.ErrObjectNotFound
+	}
+
+	return idx.getCRC32(k, i), nil
+}
+
+func (idx *MemoryIndex) getCRC32(firstLevel, secondLevel int) uint32 {
+	offset := secondLevel << 2
+	return encbin.BigEndian.Uint32(idx.CRC32[firstLevel][offset : offset+4])
+}
+
+// FindHash implements the Index interface.
+func (idx *MemoryIndex) FindHash(o int64) (plumbing.Hash, error) {
+	var hash plumbing.Hash
+	var ok bool
+
+	if idx.offsetHash != nil {
+		if hash, ok = idx.offsetHash[o]; ok {
+			return hash, nil
+		}
+	}
+
+	// Lazily generate the reverse offset/hash map if required.
+	if !idx.offsetHashIsFull || idx.offsetHash == nil {
+		if err := idx.genOffsetHash(); err != nil {
+			return plumbing.ZeroHash, err
+		}
+
+		hash, ok = idx.offsetHash[o]
+	}
+
+	if !ok {
+		return plumbing.ZeroHash, plumbing.ErrObjectNotFound
+	}
+
+	return hash, nil
+}
+
+// genOffsetHash generates the offset/hash mapping for reverse search.
+func (idx *MemoryIndex) genOffsetHash() error {
+	count, err := idx.Count()
+	if err != nil {
+		return err
+	}
+
+	idx.offsetHash = make(map[int64]plumbing.Hash, count)
+	idx.offsetHashIsFull = true
+
+	var hash plumbing.Hash
+	i := uint32(0)
+	for firstLevel, fanoutValue := range idx.Fanout {
+		mappedFirstLevel := idx.FanoutMapping[firstLevel]
+		for secondLevel := uint32(0); i < fanoutValue; i++ {
+			copy(hash[:], idx.Names[mappedFirstLevel][secondLevel*objectIDLength:])
+			offset := int64(idx.getOffset(mappedFirstLevel, int(secondLevel)))
+			idx.offsetHash[offset] = hash
+			secondLevel++
+		}
+	}
+
+	return nil
+}
+
+// Count implements the Index interface.
+func (idx *MemoryIndex) Count() (int64, error) {
+	return int64(idx.Fanout[fanout-1]), nil
+}
+
+// Entries implements the Index interface.
+func (idx *MemoryIndex) Entries() (EntryIter, error) {
+	return &idxfileEntryIter{idx, 0, 0, 0}, nil
+}
+
+// EntriesByOffset implements the Index interface.
+func (idx *MemoryIndex) EntriesByOffset() (EntryIter, error) {
+	count, err := idx.Count()
+	if err != nil {
+		return nil, err
+	}
+
+	iter := &idxfileEntryOffsetIter{
+		entries: make(entriesByOffset, count),
+	}
+
+	entries, err := idx.Entries()
+	if err != nil {
+		return nil, err
+	}
+
+	for pos := 0; int64(pos) < count; pos++ {
+		entry, err := entries.Next()
+		if err != nil {
+			return nil, err
+		}
+
+		iter.entries[pos] = entry
+	}
+
+	sort.Sort(iter.entries)
+
+	return iter, nil
+}
+
+// EntryIter is an iterator that will return the entries in a packfile index.
+type EntryIter interface {
+	// Next returns the next entry in the packfile index.
+	Next() (*Entry, error)
+	// Close closes the iterator.
+	Close() error
+}
+
+type idxfileEntryIter struct {
+	idx                     *MemoryIndex
+	total                   int
+	firstLevel, secondLevel int
+}
+
+func (i *idxfileEntryIter) Next() (*Entry, error) {
+	for {
+		if i.firstLevel >= fanout {
+			return nil, io.EOF
+		}
+
+		if i.total >= int(i.idx.Fanout[i.firstLevel]) {
+			i.firstLevel++
+			i.secondLevel = 0
+			continue
+		}
+
+		mappedFirstLevel := i.idx.FanoutMapping[i.firstLevel]
+		entry := new(Entry)
+		copy(entry.Hash[:], i.idx.Names[mappedFirstLevel][i.secondLevel*objectIDLength:])
+		entry.Offset = i.idx.getOffset(mappedFirstLevel, i.secondLevel)
+		entry.CRC32 = i.idx.getCRC32(mappedFirstLevel, i.secondLevel)
+
+		i.secondLevel++
+		i.total++
+
+		return entry, nil
+	}
+}
+
+func (i *idxfileEntryIter) Close() error {
+	i.firstLevel = fanout
+	return nil
+}
+
+// Entry is the in memory representation of an object entry in the idx file.
+type Entry struct {
+	Hash   plumbing.Hash
+	CRC32  uint32
+	Offset uint64
+}
+
+type idxfileEntryOffsetIter struct {
+	entries entriesByOffset
+	pos     int
+}
+
+func (i *idxfileEntryOffsetIter) Next() (*Entry, error) {
+	if i.pos >= len(i.entries) {
+		return nil, io.EOF
+	}
+
+	entry := i.entries[i.pos]
+	i.pos++
+
+	return entry, nil
+}
+
+func (i *idxfileEntryOffsetIter) Close() error {
+	i.pos = len(i.entries) + 1
+	return nil
+}
+
+type entriesByOffset []*Entry
+
+func (o entriesByOffset) Len() int {
+	return len(o)
+}
+
+func (o entriesByOffset) Less(i int, j int) bool {
+	return o[i].Offset < o[j].Offset
+}
+
+func (o entriesByOffset) Swap(i int, j int) {
+	o[i], o[j] = o[j], o[i]
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/idxfile/writer.go

@@ -0,0 +1,193 @@
+package idxfile
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+	"sort"
+	"sync"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/utils/binary"
+)
+
+// objects implements sort.Interface and uses hash as sorting key.
+type objects []Entry
+
+// Writer implements a packfile Observer interface and is used to generate
+// indexes.
+type Writer struct {
+	m sync.Mutex
+
+	count    uint32
+	checksum plumbing.Hash
+	objects  objects
+	offset64 uint32
+	finished bool
+	index    *MemoryIndex
+	added    map[plumbing.Hash]struct{}
+}
+
+// Index returns a previously created MemoryIndex or creates a new one if
+// needed.
+func (w *Writer) Index() (*MemoryIndex, error) {
+	w.m.Lock()
+	defer w.m.Unlock()
+
+	if w.index == nil {
+		return w.createIndex()
+	}
+
+	return w.index, nil
+}
+
+// Add appends new object data.
+func (w *Writer) Add(h plumbing.Hash, pos uint64, crc uint32) {
+	w.m.Lock()
+	defer w.m.Unlock()
+
+	if w.added == nil {
+		w.added = make(map[plumbing.Hash]struct{})
+	}
+
+	if _, ok := w.added[h]; !ok {
+		w.added[h] = struct{}{}
+		w.objects = append(w.objects, Entry{h, crc, pos})
+	}
+
+}
+
+func (w *Writer) Finished() bool {
+	return w.finished
+}
+
+// OnHeader implements packfile.Observer interface.
+func (w *Writer) OnHeader(count uint32) error {
+	w.count = count
+	w.objects = make(objects, 0, count)
+	return nil
+}
+
+// OnInflatedObjectHeader implements packfile.Observer interface.
+func (w *Writer) OnInflatedObjectHeader(t plumbing.ObjectType, objSize int64, pos int64) error {
+	return nil
+}
+
+// OnInflatedObjectContent implements packfile.Observer interface.
+func (w *Writer) OnInflatedObjectContent(h plumbing.Hash, pos int64, crc uint32, _ []byte) error {
+	w.Add(h, uint64(pos), crc)
+	return nil
+}
+
+// OnFooter implements packfile.Observer interface.
+func (w *Writer) OnFooter(h plumbing.Hash) error {
+	w.checksum = h
+	w.finished = true
+	_, err := w.createIndex()
+
+	return err
+}
+
+// creatIndex returns a filled MemoryIndex with the information filled by
+// the observer callbacks.
+func (w *Writer) createIndex() (*MemoryIndex, error) {
+	if !w.finished {
+		return nil, fmt.Errorf("the index still hasn't finished building")
+	}
+
+	idx := new(MemoryIndex)
+	w.index = idx
+
+	sort.Sort(w.objects)
+
+	// unmap all fans by default
+	for i := range idx.FanoutMapping {
+		idx.FanoutMapping[i] = noMapping
+	}
+
+	buf := new(bytes.Buffer)
+
+	last := -1
+	bucket := -1
+	for i, o := range w.objects {
+		fan := o.Hash[0]
+
+		// fill the gaps between fans
+		for j := last + 1; j < int(fan); j++ {
+			idx.Fanout[j] = uint32(i)
+		}
+
+		// update the number of objects for this position
+		idx.Fanout[fan] = uint32(i + 1)
+
+		// we move from one bucket to another, update counters and allocate
+		// memory
+		if last != int(fan) {
+			bucket++
+			idx.FanoutMapping[fan] = bucket
+			last = int(fan)
+
+			idx.Names = append(idx.Names, make([]byte, 0))
+			idx.Offset32 = append(idx.Offset32, make([]byte, 0))
+			idx.CRC32 = append(idx.CRC32, make([]byte, 0))
+		}
+
+		idx.Names[bucket] = append(idx.Names[bucket], o.Hash[:]...)
+
+		offset := o.Offset
+		if offset > math.MaxInt32 {
+			var err error
+			offset, err = w.addOffset64(offset)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		buf.Truncate(0)
+		if err := binary.WriteUint32(buf, uint32(offset)); err != nil {
+			return nil, err
+		}
+		idx.Offset32[bucket] = append(idx.Offset32[bucket], buf.Bytes()...)
+
+		buf.Truncate(0)
+		if err := binary.WriteUint32(buf, o.CRC32); err != nil {
+			return nil, err
+		}
+		idx.CRC32[bucket] = append(idx.CRC32[bucket], buf.Bytes()...)
+	}
+
+	for j := last + 1; j < 256; j++ {
+		idx.Fanout[j] = uint32(len(w.objects))
+	}
+
+	idx.Version = VersionSupported
+	idx.PackfileChecksum = w.checksum
+
+	return idx, nil
+}
+
+func (w *Writer) addOffset64(pos uint64) (uint64, error) {
+	buf := new(bytes.Buffer)
+	if err := binary.WriteUint64(buf, pos); err != nil {
+		return 0, err
+	}
+
+	w.index.Offset64 = append(w.index.Offset64, buf.Bytes()...)
+	index := uint64(w.offset64 | (1 << 31))
+	w.offset64++
+
+	return index, nil
+}
+
+func (o objects) Len() int {
+	return len(o)
+}
+
+func (o objects) Less(i int, j int) bool {
+	cmp := bytes.Compare(o[i].Hash[:], o[j].Hash[:])
+	return cmp < 0
+}
+
+func (o objects) Swap(i int, j int) {
+	o[i], o[j] = o[j], o[i]
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/index/decoder.go

@@ -0,0 +1,478 @@
+package index
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"io"
+
+	"strconv"
+	"time"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/hash"
+	"github.com/go-git/go-git/v5/utils/binary"
+)
+
+var (
+	// DecodeVersionSupported is the range of supported index versions
+	DecodeVersionSupported = struct{ Min, Max uint32 }{Min: 2, Max: 4}
+
+	// ErrMalformedSignature is returned by Decode when the index header file is
+	// malformed
+	ErrMalformedSignature = errors.New("malformed index signature file")
+	// ErrInvalidChecksum is returned by Decode if the SHA1 hash mismatch with
+	// the read content
+	ErrInvalidChecksum = errors.New("invalid checksum")
+
+	errUnknownExtension = errors.New("unknown extension")
+)
+
+const (
+	entryHeaderLength = 62
+	entryExtended     = 0x4000
+	entryValid        = 0x8000
+	nameMask          = 0xfff
+	intentToAddMask   = 1 << 13
+	skipWorkTreeMask  = 1 << 14
+)
+
+// A Decoder reads and decodes index files from an input stream.
+type Decoder struct {
+	r         io.Reader
+	hash      hash.Hash
+	lastEntry *Entry
+
+	extReader *bufio.Reader
+}
+
+// NewDecoder returns a new decoder that reads from r.
+func NewDecoder(r io.Reader) *Decoder {
+	h := hash.New(hash.CryptoType)
+	return &Decoder{
+		r:         io.TeeReader(r, h),
+		hash:      h,
+		extReader: bufio.NewReader(nil),
+	}
+}
+
+// Decode reads the whole index object from its input and stores it in the
+// value pointed to by idx.
+func (d *Decoder) Decode(idx *Index) error {
+	var err error
+	idx.Version, err = validateHeader(d.r)
+	if err != nil {
+		return err
+	}
+
+	entryCount, err := binary.ReadUint32(d.r)
+	if err != nil {
+		return err
+	}
+
+	if err := d.readEntries(idx, int(entryCount)); err != nil {
+		return err
+	}
+
+	return d.readExtensions(idx)
+}
+
+func (d *Decoder) readEntries(idx *Index, count int) error {
+	for i := 0; i < count; i++ {
+		e, err := d.readEntry(idx)
+		if err != nil {
+			return err
+		}
+
+		d.lastEntry = e
+		idx.Entries = append(idx.Entries, e)
+	}
+
+	return nil
+}
+
+func (d *Decoder) readEntry(idx *Index) (*Entry, error) {
+	e := &Entry{}
+
+	var msec, mnsec, sec, nsec uint32
+	var flags uint16
+
+	flow := []interface{}{
+		&sec, &nsec,
+		&msec, &mnsec,
+		&e.Dev,
+		&e.Inode,
+		&e.Mode,
+		&e.UID,
+		&e.GID,
+		&e.Size,
+		&e.Hash,
+		&flags,
+	}
+
+	if err := binary.Read(d.r, flow...); err != nil {
+		return nil, err
+	}
+
+	read := entryHeaderLength
+
+	if sec != 0 || nsec != 0 {
+		e.CreatedAt = time.Unix(int64(sec), int64(nsec))
+	}
+
+	if msec != 0 || mnsec != 0 {
+		e.ModifiedAt = time.Unix(int64(msec), int64(mnsec))
+	}
+
+	e.Stage = Stage(flags>>12) & 0x3
+
+	if flags&entryExtended != 0 {
+		extended, err := binary.ReadUint16(d.r)
+		if err != nil {
+			return nil, err
+		}
+
+		read += 2
+		e.IntentToAdd = extended&intentToAddMask != 0
+		e.SkipWorktree = extended&skipWorkTreeMask != 0
+	}
+
+	if err := d.readEntryName(idx, e, flags); err != nil {
+		return nil, err
+	}
+
+	return e, d.padEntry(idx, e, read)
+}
+
+func (d *Decoder) readEntryName(idx *Index, e *Entry, flags uint16) error {
+	var name string
+	var err error
+
+	switch idx.Version {
+	case 2, 3:
+		len := flags & nameMask
+		name, err = d.doReadEntryName(len)
+	case 4:
+		name, err = d.doReadEntryNameV4()
+	default:
+		return ErrUnsupportedVersion
+	}
+
+	if err != nil {
+		return err
+	}
+
+	e.Name = name
+	return nil
+}
+
+func (d *Decoder) doReadEntryNameV4() (string, error) {
+	l, err := binary.ReadVariableWidthInt(d.r)
+	if err != nil {
+		return "", err
+	}
+
+	var base string
+	if d.lastEntry != nil {
+		base = d.lastEntry.Name[:len(d.lastEntry.Name)-int(l)]
+	}
+
+	name, err := binary.ReadUntil(d.r, '\x00')
+	if err != nil {
+		return "", err
+	}
+
+	return base + string(name), nil
+}
+
+func (d *Decoder) doReadEntryName(len uint16) (string, error) {
+	name := make([]byte, len)
+	_, err := io.ReadFull(d.r, name)
+
+	return string(name), err
+}
+
+// Index entries are padded out to the next 8 byte alignment
+// for historical reasons related to how C Git read the files.
+func (d *Decoder) padEntry(idx *Index, e *Entry, read int) error {
+	if idx.Version == 4 {
+		return nil
+	}
+
+	entrySize := read + len(e.Name)
+	padLen := 8 - entrySize%8
+	_, err := io.CopyN(io.Discard, d.r, int64(padLen))
+	return err
+}
+
+func (d *Decoder) readExtensions(idx *Index) error {
+	// TODO: support 'Split index' and 'Untracked cache' extensions, take in
+	// count that they are not supported by jgit or libgit
+
+	var expected []byte
+	var err error
+
+	var header [4]byte
+	for {
+		expected = d.hash.Sum(nil)
+
+		var n int
+		if n, err = io.ReadFull(d.r, header[:]); err != nil {
+			if n == 0 {
+				err = io.EOF
+			}
+
+			break
+		}
+
+		err = d.readExtension(idx, header[:])
+		if err != nil {
+			break
+		}
+	}
+
+	if err != errUnknownExtension {
+		return err
+	}
+
+	return d.readChecksum(expected, header)
+}
+
+func (d *Decoder) readExtension(idx *Index, header []byte) error {
+	switch {
+	case bytes.Equal(header, treeExtSignature):
+		r, err := d.getExtensionReader()
+		if err != nil {
+			return err
+		}
+
+		idx.Cache = &Tree{}
+		d := &treeExtensionDecoder{r}
+		if err := d.Decode(idx.Cache); err != nil {
+			return err
+		}
+	case bytes.Equal(header, resolveUndoExtSignature):
+		r, err := d.getExtensionReader()
+		if err != nil {
+			return err
+		}
+
+		idx.ResolveUndo = &ResolveUndo{}
+		d := &resolveUndoDecoder{r}
+		if err := d.Decode(idx.ResolveUndo); err != nil {
+			return err
+		}
+	case bytes.Equal(header, endOfIndexEntryExtSignature):
+		r, err := d.getExtensionReader()
+		if err != nil {
+			return err
+		}
+
+		idx.EndOfIndexEntry = &EndOfIndexEntry{}
+		d := &endOfIndexEntryDecoder{r}
+		if err := d.Decode(idx.EndOfIndexEntry); err != nil {
+			return err
+		}
+	default:
+		return errUnknownExtension
+	}
+
+	return nil
+}
+
+func (d *Decoder) getExtensionReader() (*bufio.Reader, error) {
+	len, err := binary.ReadUint32(d.r)
+	if err != nil {
+		return nil, err
+	}
+
+	d.extReader.Reset(&io.LimitedReader{R: d.r, N: int64(len)})
+	return d.extReader, nil
+}
+
+func (d *Decoder) readChecksum(expected []byte, alreadyRead [4]byte) error {
+	var h plumbing.Hash
+	copy(h[:4], alreadyRead[:])
+
+	if _, err := io.ReadFull(d.r, h[4:]); err != nil {
+		return err
+	}
+
+	if !bytes.Equal(h[:], expected) {
+		return ErrInvalidChecksum
+	}
+
+	return nil
+}
+
+func validateHeader(r io.Reader) (version uint32, err error) {
+	var s = make([]byte, 4)
+	if _, err := io.ReadFull(r, s); err != nil {
+		return 0, err
+	}
+
+	if !bytes.Equal(s, indexSignature) {
+		return 0, ErrMalformedSignature
+	}
+
+	version, err = binary.ReadUint32(r)
+	if err != nil {
+		return 0, err
+	}
+
+	if version < DecodeVersionSupported.Min || version > DecodeVersionSupported.Max {
+		return 0, ErrUnsupportedVersion
+	}
+
+	return
+}
+
+type treeExtensionDecoder struct {
+	r *bufio.Reader
+}
+
+func (d *treeExtensionDecoder) Decode(t *Tree) error {
+	for {
+		e, err := d.readEntry()
+		if err != nil {
+			if err == io.EOF {
+				return nil
+			}
+
+			return err
+		}
+
+		if e == nil {
+			continue
+		}
+
+		t.Entries = append(t.Entries, *e)
+	}
+}
+
+func (d *treeExtensionDecoder) readEntry() (*TreeEntry, error) {
+	e := &TreeEntry{}
+
+	path, err := binary.ReadUntil(d.r, '\x00')
+	if err != nil {
+		return nil, err
+	}
+
+	e.Path = string(path)
+
+	count, err := binary.ReadUntil(d.r, ' ')
+	if err != nil {
+		return nil, err
+	}
+
+	i, err := strconv.Atoi(string(count))
+	if err != nil {
+		return nil, err
+	}
+
+	// An entry can be in an invalidated state and is represented by having a
+	// negative number in the entry_count field.
+	if i == -1 {
+		return nil, nil
+	}
+
+	e.Entries = i
+	trees, err := binary.ReadUntil(d.r, '\n')
+	if err != nil {
+		return nil, err
+	}
+
+	i, err = strconv.Atoi(string(trees))
+	if err != nil {
+		return nil, err
+	}
+
+	e.Trees = i
+	_, err = io.ReadFull(d.r, e.Hash[:])
+	if err != nil {
+		return nil, err
+	}
+	return e, nil
+}
+
+type resolveUndoDecoder struct {
+	r *bufio.Reader
+}
+
+func (d *resolveUndoDecoder) Decode(ru *ResolveUndo) error {
+	for {
+		e, err := d.readEntry()
+		if err != nil {
+			if err == io.EOF {
+				return nil
+			}
+
+			return err
+		}
+
+		ru.Entries = append(ru.Entries, *e)
+	}
+}
+
+func (d *resolveUndoDecoder) readEntry() (*ResolveUndoEntry, error) {
+	e := &ResolveUndoEntry{
+		Stages: make(map[Stage]plumbing.Hash),
+	}
+
+	path, err := binary.ReadUntil(d.r, '\x00')
+	if err != nil {
+		return nil, err
+	}
+
+	e.Path = string(path)
+
+	for i := 0; i < 3; i++ {
+		if err := d.readStage(e, Stage(i+1)); err != nil {
+			return nil, err
+		}
+	}
+
+	for s := range e.Stages {
+		var hash plumbing.Hash
+		if _, err := io.ReadFull(d.r, hash[:]); err != nil {
+			return nil, err
+		}
+
+		e.Stages[s] = hash
+	}
+
+	return e, nil
+}
+
+func (d *resolveUndoDecoder) readStage(e *ResolveUndoEntry, s Stage) error {
+	ascii, err := binary.ReadUntil(d.r, '\x00')
+	if err != nil {
+		return err
+	}
+
+	stage, err := strconv.ParseInt(string(ascii), 8, 64)
+	if err != nil {
+		return err
+	}
+
+	if stage != 0 {
+		e.Stages[s] = plumbing.ZeroHash
+	}
+
+	return nil
+}
+
+type endOfIndexEntryDecoder struct {
+	r *bufio.Reader
+}
+
+func (d *endOfIndexEntryDecoder) Decode(e *EndOfIndexEntry) error {
+	var err error
+	e.Offset, err = binary.ReadUint32(d.r)
+	if err != nil {
+		return err
+	}
+
+	_, err = io.ReadFull(d.r, e.Hash[:])
+	return err
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/index/doc.go

@@ -0,0 +1,360 @@
+// Package index implements encoding and decoding of index format files.
+//
+//	  Git index format
+//	  ================
+//
+//	  == The Git index file has the following format
+//
+//	    All binary numbers are in network byte order. Version 2 is described
+//	    here unless stated otherwise.
+//
+//	    - A 12-byte header consisting of
+//
+//	      4-byte signature:
+//	        The signature is { 'D', 'I', 'R', 'C' } (stands for "dircache")
+//
+//	      4-byte version number:
+//	        The current supported versions are 2, 3 and 4.
+//
+//	      32-bit number of index entries.
+//
+//	    - A number of sorted index entries (see below).
+//
+//	    - Extensions
+//
+//	      Extensions are identified by signature. Optional extensions can
+//	      be ignored if Git does not understand them.
+//
+//	      Git currently supports cached tree and resolve undo extensions.
+//
+//	      4-byte extension signature. If the first byte is 'A'..'Z' the
+//	      extension is optional and can be ignored.
+//
+//	      32-bit size of the extension
+//
+//	      Extension data
+//
+//	    - 160-bit SHA-1 over the content of the index file before this
+//	      checksum.
+//
+//	  == Index entry
+//
+//	    Index entries are sorted in ascending order on the name field,
+//	    interpreted as a string of unsigned bytes (i.e. memcmp() order, no
+//	    localization, no special casing of directory separator '/'). Entries
+//	    with the same name are sorted by their stage field.
+//
+//	    32-bit ctime seconds, the last time a file's metadata changed
+//	      this is stat(2) data
+//
+//	    32-bit ctime nanosecond fractions
+//	      this is stat(2) data
+//
+//	    32-bit mtime seconds, the last time a file's data changed
+//	      this is stat(2) data
+//
+//	    32-bit mtime nanosecond fractions
+//	      this is stat(2) data
+//
+//	    32-bit dev
+//	      this is stat(2) data
+//
+//	    32-bit ino
+//	      this is stat(2) data
+//
+//	    32-bit mode, split into (high to low bits)
+//
+//	      4-bit object type
+//	        valid values in binary are 1000 (regular file), 1010 (symbolic link)
+//	        and 1110 (gitlink)
+//
+//	      3-bit unused
+//
+//	      9-bit unix permission. Only 0755 and 0644 are valid for regular files.
+//	      Symbolic links and gitlinks have value 0 in this field.
+//
+//	    32-bit uid
+//	      this is stat(2) data
+//
+//	    32-bit gid
+//	      this is stat(2) data
+//
+//	    32-bit file size
+//	      This is the on-disk size from stat(2), truncated to 32-bit.
+//
+//	    160-bit SHA-1 for the represented object
+//
+//	    A 16-bit 'flags' field split into (high to low bits)
+//
+//	      1-bit assume-valid flag
+//
+//	      1-bit extended flag (must be zero in version 2)
+//
+//	      2-bit stage (during merge)
+//
+//	      12-bit name length if the length is less than 0xFFF; otherwise 0xFFF
+//	      is stored in this field.
+//
+//	    (Version 3 or later) A 16-bit field, only applicable if the
+//	    "extended flag" above is 1, split into (high to low bits).
+//
+//	      1-bit reserved for future
+//
+//	      1-bit skip-worktree flag (used by sparse checkout)
+//
+//	      1-bit intent-to-add flag (used by "git add -N")
+//
+//	      13-bit unused, must be zero
+//
+//	    Entry path name (variable length) relative to top level directory
+//	      (without leading slash). '/' is used as path separator. The special
+//	      path components ".", ".." and ".git" (without quotes) are disallowed.
+//	      Trailing slash is also disallowed.
+//
+//	      The exact encoding is undefined, but the '.' and '/' characters
+//	      are encoded in 7-bit ASCII and the encoding cannot contain a NUL
+//	      byte (iow, this is a UNIX pathname).
+//
+//	    (Version 4) In version 4, the entry path name is prefix-compressed
+//	      relative to the path name for the previous entry (the very first
+//	      entry is encoded as if the path name for the previous entry is an
+//	      empty string).  At the beginning of an entry, an integer N in the
+//	      variable width encoding (the same encoding as the offset is encoded
+//	      for OFS_DELTA pack entries; see pack-format.txt) is stored, followed
+//	      by a NUL-terminated string S.  Removing N bytes from the end of the
+//	      path name for the previous entry, and replacing it with the string S
+//	      yields the path name for this entry.
+//
+//	    1-8 nul bytes as necessary to pad the entry to a multiple of eight bytes
+//	    while keeping the name NUL-terminated.
+//
+//	    (Version 4) In version 4, the padding after the pathname does not
+//	    exist.
+//
+//	    Interpretation of index entries in split index mode is completely
+//	    different. See below for details.
+//
+//	  == Extensions
+//
+//	  === Cached tree
+//
+//	    Cached tree extension contains pre-computed hashes for trees that can
+//	    be derived from the index. It helps speed up tree object generation
+//	    from index for a new commit.
+//
+//	    When a path is updated in index, the path must be invalidated and
+//	    removed from tree cache.
+//
+//	    The signature for this extension is { 'T', 'R', 'E', 'E' }.
+//
+//	    A series of entries fill the entire extension; each of which
+//	    consists of:
+//
+//	    - NUL-terminated path component (relative to its parent directory);
+//
+//	    - ASCII decimal number of entries in the index that is covered by the
+//	      tree this entry represents (entry_count);
+//
+//	    - A space (ASCII 32);
+//
+//	    - ASCII decimal number that represents the number of subtrees this
+//	      tree has;
+//
+//	    - A newline (ASCII 10); and
+//
+//	    - 160-bit object name for the object that would result from writing
+//	      this span of index as a tree.
+//
+//	    An entry can be in an invalidated state and is represented by having
+//	    a negative number in the entry_count field. In this case, there is no
+//	    object name and the next entry starts immediately after the newline.
+//	    When writing an invalid entry, -1 should always be used as entry_count.
+//
+//	    The entries are written out in the top-down, depth-first order.  The
+//	    first entry represents the root level of the repository, followed by the
+//	    first subtree--let's call this A--of the root level (with its name
+//	    relative to the root level), followed by the first subtree of A (with
+//	    its name relative to A), ...
+//
+//	  === Resolve undo
+//
+//	    A conflict is represented in the index as a set of higher stage entries.
+//	    When a conflict is resolved (e.g. with "git add path"), these higher
+//	    stage entries will be removed and a stage-0 entry with proper resolution
+//	    is added.
+//
+//	    When these higher stage entries are removed, they are saved in the
+//	    resolve undo extension, so that conflicts can be recreated (e.g. with
+//	    "git checkout -m"), in case users want to redo a conflict resolution
+//	    from scratch.
+//
+//	    The signature for this extension is { 'R', 'E', 'U', 'C' }.
+//
+//	    A series of entries fill the entire extension; each of which
+//	    consists of:
+//
+//	    - NUL-terminated pathname the entry describes (relative to the root of
+//	      the repository, i.e. full pathname);
+//
+//	    - Three NUL-terminated ASCII octal numbers, entry mode of entries in
+//	      stage 1 to 3 (a missing stage is represented by "0" in this field);
+//	      and
+//
+//	    - At most three 160-bit object names of the entry in stages from 1 to 3
+//	      (nothing is written for a missing stage).
+//
+//	  === Split index
+//
+//	    In split index mode, the majority of index entries could be stored
+//	    in a separate file. This extension records the changes to be made on
+//	    top of that to produce the final index.
+//
+//	    The signature for this extension is { 'l', 'i', 'n', 'k' }.
+//
+//	    The extension consists of:
+//
+//	    - 160-bit SHA-1 of the shared index file. The shared index file path
+//	      is $GIT_DIR/sharedindex.<SHA-1>. If all 160 bits are zero, the
+//	      index does not require a shared index file.
+//
+//	    - An ewah-encoded delete bitmap, each bit represents an entry in the
+//	      shared index. If a bit is set, its corresponding entry in the
+//	      shared index will be removed from the final index.  Note, because
+//	      a delete operation changes index entry positions, but we do need
+//	      original positions in replace phase, it's best to just mark
+//	      entries for removal, then do a mass deletion after replacement.
+//
+//	    - An ewah-encoded replace bitmap, each bit represents an entry in
+//	      the shared index. If a bit is set, its corresponding entry in the
+//	      shared index will be replaced with an entry in this index
+//	      file. All replaced entries are stored in sorted order in this
+//	      index. The first "1" bit in the replace bitmap corresponds to the
+//	      first index entry, the second "1" bit to the second entry and so
+//	      on. Replaced entries may have empty path names to save space.
+//
+//	    The remaining index entries after replaced ones will be added to the
+//	    final index. These added entries are also sorted by entry name then
+//	    stage.
+//
+//	  == Untracked cache
+//
+//	    Untracked cache saves the untracked file list and necessary data to
+//	    verify the cache. The signature for this extension is { 'U', 'N',
+//	    'T', 'R' }.
+//
+//	    The extension starts with
+//
+//	    - A sequence of NUL-terminated strings, preceded by the size of the
+//	      sequence in variable width encoding. Each string describes the
+//	      environment where the cache can be used.
+//
+//	    - Stat data of $GIT_DIR/info/exclude. See "Index entry" section from
+//	      ctime field until "file size".
+//
+//	    - Stat data of plumbing.excludesfile
+//
+//	    - 32-bit dir_flags (see struct dir_struct)
+//
+//	    - 160-bit SHA-1 of $GIT_DIR/info/exclude. Null SHA-1 means the file
+//	      does not exist.
+//
+//	    - 160-bit SHA-1 of plumbing.excludesfile. Null SHA-1 means the file does
+//	      not exist.
+//
+//	    - NUL-terminated string of per-dir exclude file name. This usually
+//	      is ".gitignore".
+//
+//	    - The number of following directory blocks, variable width
+//	      encoding. If this number is zero, the extension ends here with a
+//	      following NUL.
+//
+//	    - A number of directory blocks in depth-first-search order, each
+//	      consists of
+//
+//	      - The number of untracked entries, variable width encoding.
+//
+//	      - The number of sub-directory blocks, variable width encoding.
+//
+//	      - The directory name terminated by NUL.
+//
+//	      - A number of untracked file/dir names terminated by NUL.
+//
+//	  The remaining data of each directory block is grouped by type:
+//
+//	    - An ewah bitmap, the n-th bit marks whether the n-th directory has
+//	      valid untracked cache entries.
+//
+//	    - An ewah bitmap, the n-th bit records "check-only" bit of
+//	      read_directory_recursive() for the n-th directory.
+//
+//	    - An ewah bitmap, the n-th bit indicates whether SHA-1 and stat data
+//	      is valid for the n-th directory and exists in the next data.
+//
+//	    - An array of stat data. The n-th data corresponds with the n-th
+//	      "one" bit in the previous ewah bitmap.
+//
+//	    - An array of SHA-1. The n-th SHA-1 corresponds with the n-th "one" bit
+//	      in the previous ewah bitmap.
+//
+//	    - One NUL.
+//
+//	 == File System Monitor cache
+//
+//	   The file system monitor cache tracks files for which the core.fsmonitor
+//	   hook has told us about changes.  The signature for this extension is
+//	   { 'F', 'S', 'M', 'N' }.
+//
+//	   The extension starts with
+//
+//	   - 32-bit version number: the current supported version is 1.
+//
+//	   - 64-bit time: the extension data reflects all changes through the given
+//	     time which is stored as the nanoseconds elapsed since midnight,
+//	     January 1, 1970.
+//
+//	  - 32-bit bitmap size: the size of the CE_FSMONITOR_VALID bitmap.
+//
+//	  - An ewah bitmap, the n-th bit indicates whether the n-th index entry
+//	    is not CE_FSMONITOR_VALID.
+//
+//	== End of Index Entry
+//
+//	  The End of Index Entry (EOIE) is used to locate the end of the variable
+//	  length index entries and the beginning of the extensions. Code can take
+//	  advantage of this to quickly locate the index extensions without having
+//	  to parse through all of the index entries.
+//
+//	  Because it must be able to be loaded before the variable length cache
+//	  entries and other index extensions, this extension must be written last.
+//	  The signature for this extension is { 'E', 'O', 'I', 'E' }.
+//
+//	  The extension consists of:
+//
+//	  - 32-bit offset to the end of the index entries
+//
+//	  - 160-bit SHA-1 over the extension types and their sizes (but not
+//	    their contents).  E.g. if we have "TREE" extension that is N-bytes
+//	    long, "REUC" extension that is M-bytes long, followed by "EOIE",
+//	    then the hash would be:
+//
+//	    SHA-1("TREE" + <binary representation of N> +
+//	      "REUC" + <binary representation of M>)
+//
+//	== Index Entry Offset Table
+//
+//	  The Index Entry Offset Table (IEOT) is used to help address the CPU
+//	  cost of loading the index by enabling multi-threading the process of
+//	  converting cache entries from the on-disk format to the in-memory format.
+//	  The signature for this extension is { 'I', 'E', 'O', 'T' }.
+//
+//	  The extension consists of:
+//
+//	  - 32-bit version (currently 1)
+//
+//	  - A number of index offset entries each consisting of:
+//
+//	  - 32-bit offset from the beginning of the file to the first cache entry
+//	    in this block of entries.
+//
+//	  - 32-bit count of cache entries in this blockpackage index
+package index

vendor/github.com/go-git/go-git/v5/plumbing/format/index/encoder.go

@@ -0,0 +1,165 @@
+package index
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"sort"
+	"time"
+
+	"github.com/go-git/go-git/v5/plumbing/hash"
+	"github.com/go-git/go-git/v5/utils/binary"
+)
+
+var (
+	// EncodeVersionSupported is the range of supported index versions
+	EncodeVersionSupported uint32 = 3
+
+	// ErrInvalidTimestamp is returned by Encode if a Index with a Entry with
+	// negative timestamp values
+	ErrInvalidTimestamp = errors.New("negative timestamps are not allowed")
+)
+
+// An Encoder writes an Index to an output stream.
+type Encoder struct {
+	w    io.Writer
+	hash hash.Hash
+}
+
+// NewEncoder returns a new encoder that writes to w.
+func NewEncoder(w io.Writer) *Encoder {
+	h := hash.New(hash.CryptoType)
+	mw := io.MultiWriter(w, h)
+	return &Encoder{mw, h}
+}
+
+// Encode writes the Index to the stream of the encoder.
+func (e *Encoder) Encode(idx *Index) error {
+	// TODO: support v4
+	// TODO: support extensions
+	if idx.Version > EncodeVersionSupported {
+		return ErrUnsupportedVersion
+	}
+
+	if err := e.encodeHeader(idx); err != nil {
+		return err
+	}
+
+	if err := e.encodeEntries(idx); err != nil {
+		return err
+	}
+
+	return e.encodeFooter()
+}
+
+func (e *Encoder) encodeHeader(idx *Index) error {
+	return binary.Write(e.w,
+		indexSignature,
+		idx.Version,
+		uint32(len(idx.Entries)),
+	)
+}
+
+func (e *Encoder) encodeEntries(idx *Index) error {
+	sort.Sort(byName(idx.Entries))
+
+	for _, entry := range idx.Entries {
+		if err := e.encodeEntry(entry); err != nil {
+			return err
+		}
+		entryLength := entryHeaderLength
+		if entry.IntentToAdd || entry.SkipWorktree {
+			entryLength += 2
+		}
+
+		wrote := entryLength + len(entry.Name)
+		if err := e.padEntry(wrote); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *Encoder) encodeEntry(entry *Entry) error {
+	sec, nsec, err := e.timeToUint32(&entry.CreatedAt)
+	if err != nil {
+		return err
+	}
+
+	msec, mnsec, err := e.timeToUint32(&entry.ModifiedAt)
+	if err != nil {
+		return err
+	}
+
+	flags := uint16(entry.Stage&0x3) << 12
+	if l := len(entry.Name); l < nameMask {
+		flags |= uint16(l)
+	} else {
+		flags |= nameMask
+	}
+
+	flow := []interface{}{
+		sec, nsec,
+		msec, mnsec,
+		entry.Dev,
+		entry.Inode,
+		entry.Mode,
+		entry.UID,
+		entry.GID,
+		entry.Size,
+		entry.Hash[:],
+	}
+
+	flagsFlow := []interface{}{flags}
+
+	if entry.IntentToAdd || entry.SkipWorktree {
+		var extendedFlags uint16
+
+		if entry.IntentToAdd {
+			extendedFlags |= intentToAddMask
+		}
+		if entry.SkipWorktree {
+			extendedFlags |= skipWorkTreeMask
+		}
+
+		flagsFlow = []interface{}{flags | entryExtended, extendedFlags}
+	}
+
+	flow = append(flow, flagsFlow...)
+
+	if err := binary.Write(e.w, flow...); err != nil {
+		return err
+	}
+
+	return binary.Write(e.w, []byte(entry.Name))
+}
+
+func (e *Encoder) timeToUint32(t *time.Time) (uint32, uint32, error) {
+	if t.IsZero() {
+		return 0, 0, nil
+	}
+
+	if t.Unix() < 0 || t.UnixNano() < 0 {
+		return 0, 0, ErrInvalidTimestamp
+	}
+
+	return uint32(t.Unix()), uint32(t.Nanosecond()), nil
+}
+
+func (e *Encoder) padEntry(wrote int) error {
+	padLen := 8 - wrote%8
+
+	_, err := e.w.Write(bytes.Repeat([]byte{'\x00'}, padLen))
+	return err
+}
+
+func (e *Encoder) encodeFooter() error {
+	return binary.Write(e.w, e.hash.Sum(nil))
+}
+
+type byName []*Entry
+
+func (l byName) Len() int           { return len(l) }
+func (l byName) Swap(i, j int)      { l[i], l[j] = l[j], l[i] }
+func (l byName) Less(i, j int) bool { return l[i].Name < l[j].Name }

vendor/github.com/go-git/go-git/v5/plumbing/format/index/index.go

@@ -0,0 +1,231 @@
+package index
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/filemode"
+)
+
+var (
+	// ErrUnsupportedVersion is returned by Decode when the index file version
+	// is not supported.
+	ErrUnsupportedVersion = errors.New("unsupported version")
+	// ErrEntryNotFound is returned by Index.Entry, if an entry is not found.
+	ErrEntryNotFound = errors.New("entry not found")
+
+	indexSignature              = []byte{'D', 'I', 'R', 'C'}
+	treeExtSignature            = []byte{'T', 'R', 'E', 'E'}
+	resolveUndoExtSignature     = []byte{'R', 'E', 'U', 'C'}
+	endOfIndexEntryExtSignature = []byte{'E', 'O', 'I', 'E'}
+)
+
+// Stage during merge
+type Stage int
+
+const (
+	// Merged is the default stage, fully merged
+	Merged Stage = 1
+	// AncestorMode is the base revision
+	AncestorMode Stage = 1
+	// OurMode is the first tree revision, ours
+	OurMode Stage = 2
+	// TheirMode is the second tree revision, theirs
+	TheirMode Stage = 3
+)
+
+// Index contains the information about which objects are currently checked out
+// in the worktree, having information about the working files. Changes in
+// worktree are detected using this Index. The Index is also used during merges
+type Index struct {
+	// Version is index version
+	Version uint32
+	// Entries collection of entries represented by this Index. The order of
+	// this collection is not guaranteed
+	Entries []*Entry
+	// Cache represents the 'Cached tree' extension
+	Cache *Tree
+	// ResolveUndo represents the 'Resolve undo' extension
+	ResolveUndo *ResolveUndo
+	// EndOfIndexEntry represents the 'End of Index Entry' extension
+	EndOfIndexEntry *EndOfIndexEntry
+}
+
+// Add creates a new Entry and returns it. The caller should first check that
+// another entry with the same path does not exist.
+func (i *Index) Add(path string) *Entry {
+	e := &Entry{
+		Name: filepath.ToSlash(path),
+	}
+
+	i.Entries = append(i.Entries, e)
+	return e
+}
+
+// Entry returns the entry that match the given path, if any.
+func (i *Index) Entry(path string) (*Entry, error) {
+	path = filepath.ToSlash(path)
+	for _, e := range i.Entries {
+		if e.Name == path {
+			return e, nil
+		}
+	}
+
+	return nil, ErrEntryNotFound
+}
+
+// Remove remove the entry that match the give path and returns deleted entry.
+func (i *Index) Remove(path string) (*Entry, error) {
+	path = filepath.ToSlash(path)
+	for index, e := range i.Entries {
+		if e.Name == path {
+			i.Entries = append(i.Entries[:index], i.Entries[index+1:]...)
+			return e, nil
+		}
+	}
+
+	return nil, ErrEntryNotFound
+}
+
+// Glob returns the all entries matching pattern or nil if there is no matching
+// entry. The syntax of patterns is the same as in filepath.Glob.
+func (i *Index) Glob(pattern string) (matches []*Entry, err error) {
+	pattern = filepath.ToSlash(pattern)
+	for _, e := range i.Entries {
+		m, err := match(pattern, e.Name)
+		if err != nil {
+			return nil, err
+		}
+
+		if m {
+			matches = append(matches, e)
+		}
+	}
+
+	return
+}
+
+// String is equivalent to `git ls-files --stage --debug`
+func (i *Index) String() string {
+	buf := bytes.NewBuffer(nil)
+	for _, e := range i.Entries {
+		buf.WriteString(e.String())
+	}
+
+	return buf.String()
+}
+
+// Entry represents a single file (or stage of a file) in the cache. An entry
+// represents exactly one stage of a file. If a file path is unmerged then
+// multiple Entry instances may appear for the same path name.
+type Entry struct {
+	// Hash is the SHA1 of the represented file
+	Hash plumbing.Hash
+	// Name is the  Entry path name relative to top level directory
+	Name string
+	// CreatedAt time when the tracked path was created
+	CreatedAt time.Time
+	// ModifiedAt time when the tracked path was changed
+	ModifiedAt time.Time
+	// Dev and Inode of the tracked path
+	Dev, Inode uint32
+	// Mode of the path
+	Mode filemode.FileMode
+	// UID and GID, userid and group id of the owner
+	UID, GID uint32
+	// Size is the length in bytes for regular files
+	Size uint32
+	// Stage on a merge is defines what stage is representing this entry
+	// https://git-scm.com/book/en/v2/Git-Tools-Advanced-Merging
+	Stage Stage
+	// SkipWorktree used in sparse checkouts
+	// https://git-scm.com/docs/git-read-tree#_sparse_checkout
+	SkipWorktree bool
+	// IntentToAdd record only the fact that the path will be added later
+	// https://git-scm.com/docs/git-add ("git add -N")
+	IntentToAdd bool
+}
+
+func (e Entry) String() string {
+	buf := bytes.NewBuffer(nil)
+
+	fmt.Fprintf(buf, "%06o %s %d\t%s\n", e.Mode, e.Hash, e.Stage, e.Name)
+	fmt.Fprintf(buf, "  ctime: %d:%d\n", e.CreatedAt.Unix(), e.CreatedAt.Nanosecond())
+	fmt.Fprintf(buf, "  mtime: %d:%d\n", e.ModifiedAt.Unix(), e.ModifiedAt.Nanosecond())
+	fmt.Fprintf(buf, "  dev: %d\tino: %d\n", e.Dev, e.Inode)
+	fmt.Fprintf(buf, "  uid: %d\tgid: %d\n", e.UID, e.GID)
+	fmt.Fprintf(buf, "  size: %d\tflags: %x\n", e.Size, 0)
+
+	return buf.String()
+}
+
+// Tree contains pre-computed hashes for trees that can be derived from the
+// index. It helps speed up tree object generation from index for a new commit.
+type Tree struct {
+	Entries []TreeEntry
+}
+
+// TreeEntry entry of a cached Tree
+type TreeEntry struct {
+	// Path component (relative to its parent directory)
+	Path string
+	// Entries is the number of entries in the index that is covered by the tree
+	// this entry represents.
+	Entries int
+	// Trees is the number that represents the number of subtrees this tree has
+	Trees int
+	// Hash object name for the object that would result from writing this span
+	// of index as a tree.
+	Hash plumbing.Hash
+}
+
+// ResolveUndo is used when a conflict is resolved (e.g. with "git add path"),
+// these higher stage entries are removed and a stage-0 entry with proper
+// resolution is added. When these higher stage entries are removed, they are
+// saved in the resolve undo extension.
+type ResolveUndo struct {
+	Entries []ResolveUndoEntry
+}
+
+// ResolveUndoEntry contains the information about a conflict when is resolved
+type ResolveUndoEntry struct {
+	Path   string
+	Stages map[Stage]plumbing.Hash
+}
+
+// EndOfIndexEntry is the End of Index Entry (EOIE) is used to locate the end of
+// the variable length index entries and the beginning of the extensions. Code
+// can take advantage of this to quickly locate the index extensions without
+// having to parse through all of the index entries.
+//
+//	Because it must be able to be loaded before the variable length cache
+//	entries and other index extensions, this extension must be written last.
+type EndOfIndexEntry struct {
+	// Offset to the end of the index entries
+	Offset uint32
+	// Hash is a SHA-1 over the extension types and their sizes (but not
+	//	their contents).
+	Hash plumbing.Hash
+}
+
+// SkipUnless applies patterns in the form of A, A/B, A/B/C
+// to the index to prevent the files from being checked out
+func (i *Index) SkipUnless(patterns []string) {
+	for _, e := range i.Entries {
+		var include bool
+		for _, pattern := range patterns {
+			if strings.HasPrefix(e.Name, pattern) {
+				include = true
+				break
+			}
+		}
+		if !include {
+			e.SkipWorktree = true
+		}
+	}
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/index/match.go

@@ -0,0 +1,186 @@
+package index
+
+import (
+	"path/filepath"
+	"runtime"
+	"unicode/utf8"
+)
+
+// match is filepath.Match with support to match fullpath and not only filenames
+// code from:
+// https://github.com/golang/go/blob/39852bf4cce6927e01d0136c7843f65a801738cb/src/path/filepath/match.go#L44-L224
+func match(pattern, name string) (matched bool, err error) {
+Pattern:
+	for len(pattern) > 0 {
+		var star bool
+		var chunk string
+		star, chunk, pattern = scanChunk(pattern)
+
+		// Look for match at current position.
+		t, ok, err := matchChunk(chunk, name)
+		// if we're the last chunk, make sure we've exhausted the name
+		// otherwise we'll give a false result even if we could still match
+		// using the star
+		if ok && (len(t) == 0 || len(pattern) > 0) {
+			name = t
+			continue
+		}
+		if err != nil {
+			return false, err
+		}
+		if star {
+			// Look for match skipping i+1 bytes.
+			// Cannot skip /.
+			for i := 0; i < len(name); i++ {
+				t, ok, err := matchChunk(chunk, name[i+1:])
+				if ok {
+					// if we're the last chunk, make sure we exhausted the name
+					if len(pattern) == 0 && len(t) > 0 {
+						continue
+					}
+					name = t
+					continue Pattern
+				}
+				if err != nil {
+					return false, err
+				}
+			}
+		}
+		return false, nil
+	}
+	return len(name) == 0, nil
+}
+
+// scanChunk gets the next segment of pattern, which is a non-star string
+// possibly preceded by a star.
+func scanChunk(pattern string) (star bool, chunk, rest string) {
+	for len(pattern) > 0 && pattern[0] == '*' {
+		pattern = pattern[1:]
+		star = true
+	}
+	inrange := false
+	var i int
+Scan:
+	for i = 0; i < len(pattern); i++ {
+		switch pattern[i] {
+		case '\\':
+			if runtime.GOOS != "windows" {
+				// error check handled in matchChunk: bad pattern.
+				if i+1 < len(pattern) {
+					i++
+				}
+			}
+		case '[':
+			inrange = true
+		case ']':
+			inrange = false
+		case '*':
+			if !inrange {
+				break Scan
+			}
+		}
+	}
+	return star, pattern[0:i], pattern[i:]
+}
+
+// matchChunk checks whether chunk matches the beginning of s.
+// If so, it returns the remainder of s (after the match).
+// Chunk is all single-character operators: literals, char classes, and ?.
+func matchChunk(chunk, s string) (rest string, ok bool, err error) {
+	for len(chunk) > 0 {
+		if len(s) == 0 {
+			return
+		}
+		switch chunk[0] {
+		case '[':
+			// character class
+			r, n := utf8.DecodeRuneInString(s)
+			s = s[n:]
+			chunk = chunk[1:]
+			// We can't end right after '[', we're expecting at least
+			// a closing bracket and possibly a caret.
+			if len(chunk) == 0 {
+				err = filepath.ErrBadPattern
+				return
+			}
+			// possibly negated
+			negated := chunk[0] == '^'
+			if negated {
+				chunk = chunk[1:]
+			}
+			// parse all ranges
+			match := false
+			nrange := 0
+			for {
+				if len(chunk) > 0 && chunk[0] == ']' && nrange > 0 {
+					chunk = chunk[1:]
+					break
+				}
+				var lo, hi rune
+				if lo, chunk, err = getEsc(chunk); err != nil {
+					return
+				}
+				hi = lo
+				if chunk[0] == '-' {
+					if hi, chunk, err = getEsc(chunk[1:]); err != nil {
+						return
+					}
+				}
+				if lo <= r && r <= hi {
+					match = true
+				}
+				nrange++
+			}
+			if match == negated {
+				return
+			}
+
+		case '?':
+			_, n := utf8.DecodeRuneInString(s)
+			s = s[n:]
+			chunk = chunk[1:]
+
+		case '\\':
+			if runtime.GOOS != "windows" {
+				chunk = chunk[1:]
+				if len(chunk) == 0 {
+					err = filepath.ErrBadPattern
+					return
+				}
+			}
+			fallthrough
+
+		default:
+			if chunk[0] != s[0] {
+				return
+			}
+			s = s[1:]
+			chunk = chunk[1:]
+		}
+	}
+	return s, true, nil
+}
+
+// getEsc gets a possibly-escaped character from chunk, for a character class.
+func getEsc(chunk string) (r rune, nchunk string, err error) {
+	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
+		err = filepath.ErrBadPattern
+		return
+	}
+	if chunk[0] == '\\' && runtime.GOOS != "windows" {
+		chunk = chunk[1:]
+		if len(chunk) == 0 {
+			err = filepath.ErrBadPattern
+			return
+		}
+	}
+	r, n := utf8.DecodeRuneInString(chunk)
+	if r == utf8.RuneError && n == 1 {
+		err = filepath.ErrBadPattern
+	}
+	nchunk = chunk[n:]
+	if len(nchunk) == 0 {
+		err = filepath.ErrBadPattern
+	}
+	return
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/objfile/doc.go

@@ -0,0 +1,2 @@
+// Package objfile implements encoding and decoding of object files.
+package objfile

vendor/github.com/go-git/go-git/v5/plumbing/format/objfile/reader.go

@@ -0,0 +1,117 @@
+package objfile
+
+import (
+	"errors"
+	"io"
+	"strconv"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/format/packfile"
+	"github.com/go-git/go-git/v5/utils/sync"
+)
+
+var (
+	ErrClosed       = errors.New("objfile: already closed")
+	ErrHeader       = errors.New("objfile: invalid header")
+	ErrNegativeSize = errors.New("objfile: negative object size")
+)
+
+// Reader reads and decodes compressed objfile data from a provided io.Reader.
+// Reader implements io.ReadCloser. Close should be called when finished with
+// the Reader. Close will not close the underlying io.Reader.
+type Reader struct {
+	multi   io.Reader
+	zlib    io.Reader
+	zlibref sync.ZLibReader
+	hasher  plumbing.Hasher
+}
+
+// NewReader returns a new Reader reading from r.
+func NewReader(r io.Reader) (*Reader, error) {
+	zlib, err := sync.GetZlibReader(r)
+	if err != nil {
+		return nil, packfile.ErrZLib.AddDetails(err.Error())
+	}
+
+	return &Reader{
+		zlib:    zlib.Reader,
+		zlibref: zlib,
+	}, nil
+}
+
+// Header reads the type and the size of object, and prepares the reader for read
+func (r *Reader) Header() (t plumbing.ObjectType, size int64, err error) {
+	var raw []byte
+	raw, err = r.readUntil(' ')
+	if err != nil {
+		return
+	}
+
+	t, err = plumbing.ParseObjectType(string(raw))
+	if err != nil {
+		return
+	}
+
+	raw, err = r.readUntil(0)
+	if err != nil {
+		return
+	}
+
+	size, err = strconv.ParseInt(string(raw), 10, 64)
+	if err != nil {
+		err = ErrHeader
+		return
+	}
+
+	defer r.prepareForRead(t, size)
+	return
+}
+
+// readSlice reads one byte at a time from r until it encounters delim or an
+// error.
+func (r *Reader) readUntil(delim byte) ([]byte, error) {
+	var buf [1]byte
+	value := make([]byte, 0, 16)
+	for {
+		if n, err := r.zlib.Read(buf[:]); err != nil && (err != io.EOF || n == 0) {
+			if err == io.EOF {
+				return nil, ErrHeader
+			}
+			return nil, err
+		}
+
+		if buf[0] == delim {
+			return value, nil
+		}
+
+		value = append(value, buf[0])
+	}
+}
+
+func (r *Reader) prepareForRead(t plumbing.ObjectType, size int64) {
+	r.hasher = plumbing.NewHasher(t, size)
+	r.multi = io.TeeReader(r.zlib, r.hasher)
+}
+
+// Read reads len(p) bytes into p from the object data stream. It returns
+// the number of bytes read (0 <= n <= len(p)) and any error encountered. Even
+// if Read returns n < len(p), it may use all of p as scratch space during the
+// call.
+//
+// If Read encounters the end of the data stream it will return err == io.EOF,
+// either in the current call if n > 0 or in a subsequent call.
+func (r *Reader) Read(p []byte) (n int, err error) {
+	return r.multi.Read(p)
+}
+
+// Hash returns the hash of the object data stream that has been read so far.
+func (r *Reader) Hash() plumbing.Hash {
+	return r.hasher.Sum()
+}
+
+// Close releases any resources consumed by the Reader. Calling Close does not
+// close the wrapped io.Reader originally passed to NewReader.
+func (r *Reader) Close() error {
+	sync.PutZlibReader(r.zlibref)
+	return nil
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/objfile/writer.go

@@ -0,0 +1,112 @@
+package objfile
+
+import (
+	"compress/zlib"
+	"errors"
+	"io"
+	"strconv"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/utils/sync"
+)
+
+var (
+	ErrOverflow = errors.New("objfile: declared data length exceeded (overflow)")
+)
+
+// Writer writes and encodes data in compressed objfile format to a provided
+// io.Writer. Close should be called when finished with the Writer. Close will
+// not close the underlying io.Writer.
+type Writer struct {
+	raw    io.Writer
+	hasher plumbing.Hasher
+	multi  io.Writer
+	zlib   *zlib.Writer
+
+	closed  bool
+	pending int64 // number of unwritten bytes
+}
+
+// NewWriter returns a new Writer writing to w.
+//
+// The returned Writer implements io.WriteCloser. Close should be called when
+// finished with the Writer. Close will not close the underlying io.Writer.
+func NewWriter(w io.Writer) *Writer {
+	zlib := sync.GetZlibWriter(w)
+	return &Writer{
+		raw:  w,
+		zlib: zlib,
+	}
+}
+
+// WriteHeader writes the type and the size and prepares to accept the object's
+// contents. If an invalid t is provided, plumbing.ErrInvalidType is returned. If a
+// negative size is provided, ErrNegativeSize is returned.
+func (w *Writer) WriteHeader(t plumbing.ObjectType, size int64) error {
+	if !t.Valid() {
+		return plumbing.ErrInvalidType
+	}
+	if size < 0 {
+		return ErrNegativeSize
+	}
+
+	b := t.Bytes()
+	b = append(b, ' ')
+	b = append(b, []byte(strconv.FormatInt(size, 10))...)
+	b = append(b, 0)
+
+	defer w.prepareForWrite(t, size)
+	_, err := w.zlib.Write(b)
+
+	return err
+}
+
+func (w *Writer) prepareForWrite(t plumbing.ObjectType, size int64) {
+	w.pending = size
+
+	w.hasher = plumbing.NewHasher(t, size)
+	w.multi = io.MultiWriter(w.zlib, w.hasher)
+}
+
+// Write writes the object's contents. Write returns the error ErrOverflow if
+// more than size bytes are written after WriteHeader.
+func (w *Writer) Write(p []byte) (n int, err error) {
+	if w.closed {
+		return 0, ErrClosed
+	}
+
+	overwrite := false
+	if int64(len(p)) > w.pending {
+		p = p[0:w.pending]
+		overwrite = true
+	}
+
+	n, err = w.multi.Write(p)
+	w.pending -= int64(n)
+	if err == nil && overwrite {
+		err = ErrOverflow
+		return
+	}
+
+	return
+}
+
+// Hash returns the hash of the object data stream that has been written so far.
+// It can be called before or after Close.
+func (w *Writer) Hash() plumbing.Hash {
+	return w.hasher.Sum() // Not yet closed, return hash of data written so far
+}
+
+// Close releases any resources consumed by the Writer.
+//
+// Calling Close does not close the wrapped io.Writer originally passed to
+// NewWriter.
+func (w *Writer) Close() error {
+	defer sync.PutZlibWriter(w.zlib)
+	if err := w.zlib.Close(); err != nil {
+		return err
+	}
+
+	w.closed = true
+	return nil
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/packfile/common.go

@@ -0,0 +1,60 @@
+package packfile
+
+import (
+	"io"
+
+	"github.com/go-git/go-git/v5/plumbing/storer"
+	"github.com/go-git/go-git/v5/utils/ioutil"
+)
+
+var signature = []byte{'P', 'A', 'C', 'K'}
+
+const (
+	// VersionSupported is the packfile version supported by this package
+	VersionSupported uint32 = 2
+
+	firstLengthBits = uint8(4)   // the first byte into object header has 4 bits to store the length
+	lengthBits      = uint8(7)   // subsequent bytes has 7 bits to store the length
+	maskFirstLength = 15         // 0000 1111
+	maskContinue    = 0x80       // 1000 0000
+	maskLength      = uint8(127) // 0111 1111
+	maskType        = uint8(112) // 0111 0000
+)
+
+// UpdateObjectStorage updates the storer with the objects in the given
+// packfile.
+func UpdateObjectStorage(s storer.Storer, packfile io.Reader) error {
+	if pw, ok := s.(storer.PackfileWriter); ok {
+		return WritePackfileToObjectStorage(pw, packfile)
+	}
+
+	p, err := NewParserWithStorage(NewScanner(packfile), s)
+	if err != nil {
+		return err
+	}
+
+	_, err = p.Parse()
+	return err
+}
+
+// WritePackfileToObjectStorage writes all the packfile objects into the given
+// object storage.
+func WritePackfileToObjectStorage(
+	sw storer.PackfileWriter,
+	packfile io.Reader,
+) (err error) {
+	w, err := sw.PackfileWriter()
+	if err != nil {
+		return err
+	}
+
+	defer ioutil.CheckClose(w, &err)
+
+	var n int64
+	n, err = io.Copy(w, packfile)
+	if err == nil && n == 0 {
+		return ErrEmptyPackfile
+	}
+
+	return err
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/packfile/delta_index.go

@@ -0,0 +1,297 @@
+package packfile
+
+const blksz = 16
+const maxChainLength = 64
+
+// deltaIndex is a modified version of JGit's DeltaIndex adapted to our current
+// design.
+type deltaIndex struct {
+	table   []int
+	entries []int
+	mask    int
+}
+
+func (idx *deltaIndex) init(buf []byte) {
+	scanner := newDeltaIndexScanner(buf, len(buf))
+	idx.mask = scanner.mask
+	idx.table = scanner.table
+	idx.entries = make([]int, countEntries(scanner)+1)
+	idx.copyEntries(scanner)
+}
+
+// findMatch returns the offset of src where the block starting at tgtOffset
+// is and the length of the match. A length of 0 means there was no match. A
+// length of -1 means the src length is lower than the blksz and whatever
+// other positive length is the length of the match in bytes.
+func (idx *deltaIndex) findMatch(src, tgt []byte, tgtOffset int) (srcOffset, l int) {
+	if len(tgt) < tgtOffset+s {
+		return 0, len(tgt) - tgtOffset
+	}
+
+	if len(src) < blksz {
+		return 0, -1
+	}
+
+	if len(tgt) >= tgtOffset+s && len(src) >= blksz {
+		h := hashBlock(tgt, tgtOffset)
+		tIdx := h & idx.mask
+		eIdx := idx.table[tIdx]
+		if eIdx != 0 {
+			srcOffset = idx.entries[eIdx]
+		} else {
+			return
+		}
+
+		l = matchLength(src, tgt, tgtOffset, srcOffset)
+	}
+
+	return
+}
+
+func matchLength(src, tgt []byte, otgt, osrc int) (l int) {
+	lensrc := len(src)
+	lentgt := len(tgt)
+	for (osrc < lensrc && otgt < lentgt) && src[osrc] == tgt[otgt] {
+		l++
+		osrc++
+		otgt++
+	}
+	return
+}
+
+func countEntries(scan *deltaIndexScanner) (cnt int) {
+	// Figure out exactly how many entries we need. As we do the
+	// enumeration truncate any delta chains longer than what we
+	// are willing to scan during encode. This keeps the encode
+	// logic linear in the size of the input rather than quadratic.
+	for i := 0; i < len(scan.table); i++ {
+		h := scan.table[i]
+		if h == 0 {
+			continue
+		}
+
+		size := 0
+		for {
+			size++
+			if size == maxChainLength {
+				scan.next[h] = 0
+				break
+			}
+			h = scan.next[h]
+
+			if h == 0 {
+				break
+			}
+		}
+		cnt += size
+	}
+
+	return
+}
+
+func (idx *deltaIndex) copyEntries(scanner *deltaIndexScanner) {
+	// Rebuild the entries list from the scanner, positioning all
+	// blocks in the same hash chain next to each other. We can
+	// then later discard the next list, along with the scanner.
+	//
+	next := 1
+	for i := 0; i < len(idx.table); i++ {
+		h := idx.table[i]
+		if h == 0 {
+			continue
+		}
+
+		idx.table[i] = next
+		for {
+			idx.entries[next] = scanner.entries[h]
+			next++
+			h = scanner.next[h]
+
+			if h == 0 {
+				break
+			}
+		}
+	}
+}
+
+type deltaIndexScanner struct {
+	table   []int
+	entries []int
+	next    []int
+	mask    int
+	count   int
+}
+
+func newDeltaIndexScanner(buf []byte, size int) *deltaIndexScanner {
+	size -= size % blksz
+	worstCaseBlockCnt := size / blksz
+	if worstCaseBlockCnt < 1 {
+		return new(deltaIndexScanner)
+	}
+
+	tableSize := tableSize(worstCaseBlockCnt)
+	scanner := &deltaIndexScanner{
+		table:   make([]int, tableSize),
+		mask:    tableSize - 1,
+		entries: make([]int, worstCaseBlockCnt+1),
+		next:    make([]int, worstCaseBlockCnt+1),
+	}
+
+	scanner.scan(buf, size)
+	return scanner
+}
+
+// slightly modified version of JGit's DeltaIndexScanner. We store the offset on the entries
+// instead of the entries and the key, so we avoid operations to retrieve the offset later, as
+// we don't use the key.
+// See: https://github.com/eclipse/jgit/blob/005e5feb4ecd08c4e4d141a38b9e7942accb3212/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/pack/DeltaIndexScanner.java
+func (s *deltaIndexScanner) scan(buf []byte, end int) {
+	lastHash := 0
+	ptr := end - blksz
+
+	for {
+		key := hashBlock(buf, ptr)
+		tIdx := key & s.mask
+		head := s.table[tIdx]
+		if head != 0 && lastHash == key {
+			s.entries[head] = ptr
+		} else {
+			s.count++
+			eIdx := s.count
+			s.entries[eIdx] = ptr
+			s.next[eIdx] = head
+			s.table[tIdx] = eIdx
+		}
+
+		lastHash = key
+		ptr -= blksz
+
+		if 0 > ptr {
+			break
+		}
+	}
+}
+
+func tableSize(worstCaseBlockCnt int) int {
+	shift := 32 - leadingZeros(uint32(worstCaseBlockCnt))
+	sz := 1 << uint(shift-1)
+	if sz < worstCaseBlockCnt {
+		sz <<= 1
+	}
+	return sz
+}
+
+// use https://golang.org/pkg/math/bits/#LeadingZeros32 in the future
+func leadingZeros(x uint32) (n int) {
+	if x >= 1<<16 {
+		x >>= 16
+		n = 16
+	}
+	if x >= 1<<8 {
+		x >>= 8
+		n += 8
+	}
+	n += int(len8tab[x])
+	return 32 - n
+}
+
+var len8tab = [256]uint8{
+	0x00, 0x01, 0x02, 0x02, 0x03, 0x03, 0x03, 0x03, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+	0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+	0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+	0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+}
+
+func hashBlock(raw []byte, ptr int) int {
+	// The first 4 steps collapse out into a 4 byte big-endian decode,
+	// with a larger right shift as we combined shift lefts together.
+	//
+	hash := ((uint32(raw[ptr]) & 0xff) << 24) |
+		((uint32(raw[ptr+1]) & 0xff) << 16) |
+		((uint32(raw[ptr+2]) & 0xff) << 8) |
+		(uint32(raw[ptr+3]) & 0xff)
+	hash ^= T[hash>>31]
+
+	hash = ((hash << 8) | (uint32(raw[ptr+4]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+5]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+6]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+7]) & 0xff)) ^ T[hash>>23]
+
+	hash = ((hash << 8) | (uint32(raw[ptr+8]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+9]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+10]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+11]) & 0xff)) ^ T[hash>>23]
+
+	hash = ((hash << 8) | (uint32(raw[ptr+12]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+13]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+14]) & 0xff)) ^ T[hash>>23]
+	hash = ((hash << 8) | (uint32(raw[ptr+15]) & 0xff)) ^ T[hash>>23]
+
+	return int(hash)
+}
+
+var T = []uint32{0x00000000, 0xd4c6b32d, 0x7d4bd577,
+	0xa98d665a, 0x2e5119c3, 0xfa97aaee, 0x531accb4, 0x87dc7f99,
+	0x5ca23386, 0x886480ab, 0x21e9e6f1, 0xf52f55dc, 0x72f32a45,
+	0xa6359968, 0x0fb8ff32, 0xdb7e4c1f, 0x6d82d421, 0xb944670c,
+	0x10c90156, 0xc40fb27b, 0x43d3cde2, 0x97157ecf, 0x3e981895,
+	0xea5eabb8, 0x3120e7a7, 0xe5e6548a, 0x4c6b32d0, 0x98ad81fd,
+	0x1f71fe64, 0xcbb74d49, 0x623a2b13, 0xb6fc983e, 0x0fc31b6f,
+	0xdb05a842, 0x7288ce18, 0xa64e7d35, 0x219202ac, 0xf554b181,
+	0x5cd9d7db, 0x881f64f6, 0x536128e9, 0x87a79bc4, 0x2e2afd9e,
+	0xfaec4eb3, 0x7d30312a, 0xa9f68207, 0x007be45d, 0xd4bd5770,
+	0x6241cf4e, 0xb6877c63, 0x1f0a1a39, 0xcbcca914, 0x4c10d68d,
+	0x98d665a0, 0x315b03fa, 0xe59db0d7, 0x3ee3fcc8, 0xea254fe5,
+	0x43a829bf, 0x976e9a92, 0x10b2e50b, 0xc4745626, 0x6df9307c,
+	0xb93f8351, 0x1f8636de, 0xcb4085f3, 0x62cde3a9, 0xb60b5084,
+	0x31d72f1d, 0xe5119c30, 0x4c9cfa6a, 0x985a4947, 0x43240558,
+	0x97e2b675, 0x3e6fd02f, 0xeaa96302, 0x6d751c9b, 0xb9b3afb6,
+	0x103ec9ec, 0xc4f87ac1, 0x7204e2ff, 0xa6c251d2, 0x0f4f3788,
+	0xdb8984a5, 0x5c55fb3c, 0x88934811, 0x211e2e4b, 0xf5d89d66,
+	0x2ea6d179, 0xfa606254, 0x53ed040e, 0x872bb723, 0x00f7c8ba,
+	0xd4317b97, 0x7dbc1dcd, 0xa97aaee0, 0x10452db1, 0xc4839e9c,
+	0x6d0ef8c6, 0xb9c84beb, 0x3e143472, 0xead2875f, 0x435fe105,
+	0x97995228, 0x4ce71e37, 0x9821ad1a, 0x31accb40, 0xe56a786d,
+	0x62b607f4, 0xb670b4d9, 0x1ffdd283, 0xcb3b61ae, 0x7dc7f990,
+	0xa9014abd, 0x008c2ce7, 0xd44a9fca, 0x5396e053, 0x8750537e,
+	0x2edd3524, 0xfa1b8609, 0x2165ca16, 0xf5a3793b, 0x5c2e1f61,
+	0x88e8ac4c, 0x0f34d3d5, 0xdbf260f8, 0x727f06a2, 0xa6b9b58f,
+	0x3f0c6dbc, 0xebcade91, 0x4247b8cb, 0x96810be6, 0x115d747f,
+	0xc59bc752, 0x6c16a108, 0xb8d01225, 0x63ae5e3a, 0xb768ed17,
+	0x1ee58b4d, 0xca233860, 0x4dff47f9, 0x9939f4d4, 0x30b4928e,
+	0xe47221a3, 0x528eb99d, 0x86480ab0, 0x2fc56cea, 0xfb03dfc7,
+	0x7cdfa05e, 0xa8191373, 0x01947529, 0xd552c604, 0x0e2c8a1b,
+	0xdaea3936, 0x73675f6c, 0xa7a1ec41, 0x207d93d8, 0xf4bb20f5,
+	0x5d3646af, 0x89f0f582, 0x30cf76d3, 0xe409c5fe, 0x4d84a3a4,
+	0x99421089, 0x1e9e6f10, 0xca58dc3d, 0x63d5ba67, 0xb713094a,
+	0x6c6d4555, 0xb8abf678, 0x11269022, 0xc5e0230f, 0x423c5c96,
+	0x96faefbb, 0x3f7789e1, 0xebb13acc, 0x5d4da2f2, 0x898b11df,
+	0x20067785, 0xf4c0c4a8, 0x731cbb31, 0xa7da081c, 0x0e576e46,
+	0xda91dd6b, 0x01ef9174, 0xd5292259, 0x7ca44403, 0xa862f72e,
+	0x2fbe88b7, 0xfb783b9a, 0x52f55dc0, 0x8633eeed, 0x208a5b62,
+	0xf44ce84f, 0x5dc18e15, 0x89073d38, 0x0edb42a1, 0xda1df18c,
+	0x739097d6, 0xa75624fb, 0x7c2868e4, 0xa8eedbc9, 0x0163bd93,
+	0xd5a50ebe, 0x52797127, 0x86bfc20a, 0x2f32a450, 0xfbf4177d,
+	0x4d088f43, 0x99ce3c6e, 0x30435a34, 0xe485e919, 0x63599680,
+	0xb79f25ad, 0x1e1243f7, 0xcad4f0da, 0x11aabcc5, 0xc56c0fe8,
+	0x6ce169b2, 0xb827da9f, 0x3ffba506, 0xeb3d162b, 0x42b07071,
+	0x9676c35c, 0x2f49400d, 0xfb8ff320, 0x5202957a, 0x86c42657,
+	0x011859ce, 0xd5deeae3, 0x7c538cb9, 0xa8953f94, 0x73eb738b,
+	0xa72dc0a6, 0x0ea0a6fc, 0xda6615d1, 0x5dba6a48, 0x897cd965,
+	0x20f1bf3f, 0xf4370c12, 0x42cb942c, 0x960d2701, 0x3f80415b,
+	0xeb46f276, 0x6c9a8def, 0xb85c3ec2, 0x11d15898, 0xc517ebb5,
+	0x1e69a7aa, 0xcaaf1487, 0x632272dd, 0xb7e4c1f0, 0x3038be69,
+	0xe4fe0d44, 0x4d736b1e, 0x99b5d833,
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/packfile/delta_selector.go

@@ -0,0 +1,369 @@
+package packfile
+
+import (
+	"sort"
+	"sync"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/storer"
+)
+
+const (
+	// deltas based on deltas, how many steps we can do.
+	// 50 is the default value used in JGit
+	maxDepth = int64(50)
+)
+
+// applyDelta is the set of object types that we should apply deltas
+var applyDelta = map[plumbing.ObjectType]bool{
+	plumbing.BlobObject: true,
+	plumbing.TreeObject: true,
+}
+
+type deltaSelector struct {
+	storer storer.EncodedObjectStorer
+}
+
+func newDeltaSelector(s storer.EncodedObjectStorer) *deltaSelector {
+	return &deltaSelector{s}
+}
+
+// ObjectsToPack creates a list of ObjectToPack from the hashes
+// provided, creating deltas if it's suitable, using an specific
+// internal logic.  `packWindow` specifies the size of the sliding
+// window used to compare objects for delta compression; 0 turns off
+// delta compression entirely.
+func (dw *deltaSelector) ObjectsToPack(
+	hashes []plumbing.Hash,
+	packWindow uint,
+) ([]*ObjectToPack, error) {
+	otp, err := dw.objectsToPack(hashes, packWindow)
+	if err != nil {
+		return nil, err
+	}
+
+	if packWindow == 0 {
+		return otp, nil
+	}
+
+	dw.sort(otp)
+
+	var objectGroups [][]*ObjectToPack
+	var prev *ObjectToPack
+	i := -1
+	for _, obj := range otp {
+		if prev == nil || prev.Type() != obj.Type() {
+			objectGroups = append(objectGroups, []*ObjectToPack{obj})
+			i++
+			prev = obj
+		} else {
+			objectGroups[i] = append(objectGroups[i], obj)
+		}
+	}
+
+	var wg sync.WaitGroup
+	var once sync.Once
+	for _, objs := range objectGroups {
+		objs := objs
+		wg.Add(1)
+		go func() {
+			if walkErr := dw.walk(objs, packWindow); walkErr != nil {
+				once.Do(func() {
+					err = walkErr
+				})
+			}
+			wg.Done()
+		}()
+	}
+	wg.Wait()
+
+	if err != nil {
+		return nil, err
+	}
+
+	return otp, nil
+}
+
+func (dw *deltaSelector) objectsToPack(
+	hashes []plumbing.Hash,
+	packWindow uint,
+) ([]*ObjectToPack, error) {
+	var objectsToPack []*ObjectToPack
+	for _, h := range hashes {
+		var o plumbing.EncodedObject
+		var err error
+		if packWindow == 0 {
+			o, err = dw.encodedObject(h)
+		} else {
+			o, err = dw.encodedDeltaObject(h)
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		otp := newObjectToPack(o)
+		if _, ok := o.(plumbing.DeltaObject); ok {
+			otp.CleanOriginal()
+		}
+
+		objectsToPack = append(objectsToPack, otp)
+	}
+
+	if packWindow == 0 {
+		return objectsToPack, nil
+	}
+
+	if err := dw.fixAndBreakChains(objectsToPack); err != nil {
+		return nil, err
+	}
+
+	return objectsToPack, nil
+}
+
+func (dw *deltaSelector) encodedDeltaObject(h plumbing.Hash) (plumbing.EncodedObject, error) {
+	edos, ok := dw.storer.(storer.DeltaObjectStorer)
+	if !ok {
+		return dw.encodedObject(h)
+	}
+
+	return edos.DeltaObject(plumbing.AnyObject, h)
+}
+
+func (dw *deltaSelector) encodedObject(h plumbing.Hash) (plumbing.EncodedObject, error) {
+	return dw.storer.EncodedObject(plumbing.AnyObject, h)
+}
+
+func (dw *deltaSelector) fixAndBreakChains(objectsToPack []*ObjectToPack) error {
+	m := make(map[plumbing.Hash]*ObjectToPack, len(objectsToPack))
+	for _, otp := range objectsToPack {
+		m[otp.Hash()] = otp
+	}
+
+	for _, otp := range objectsToPack {
+		if err := dw.fixAndBreakChainsOne(m, otp); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (dw *deltaSelector) fixAndBreakChainsOne(objectsToPack map[plumbing.Hash]*ObjectToPack, otp *ObjectToPack) error {
+	if !otp.Object.Type().IsDelta() {
+		return nil
+	}
+
+	// Initial ObjectToPack instances might have a delta assigned to Object
+	// but no actual base initially. Once Base is assigned to a delta, it means
+	// we already fixed it.
+	if otp.Base != nil {
+		return nil
+	}
+
+	do, ok := otp.Object.(plumbing.DeltaObject)
+	if !ok {
+		// if this is not a DeltaObject, then we cannot retrieve its base,
+		// so we have to break the delta chain here.
+		return dw.undeltify(otp)
+	}
+
+	base, ok := objectsToPack[do.BaseHash()]
+	if !ok {
+		// The base of the delta is not in our list of objects to pack, so
+		// we break the chain.
+		return dw.undeltify(otp)
+	}
+
+	if err := dw.fixAndBreakChainsOne(objectsToPack, base); err != nil {
+		return err
+	}
+
+	otp.SetDelta(base, otp.Object)
+	return nil
+}
+
+func (dw *deltaSelector) restoreOriginal(otp *ObjectToPack) error {
+	if otp.Original != nil {
+		return nil
+	}
+
+	if !otp.Object.Type().IsDelta() {
+		return nil
+	}
+
+	obj, err := dw.encodedObject(otp.Hash())
+	if err != nil {
+		return err
+	}
+
+	otp.SetOriginal(obj)
+
+	return nil
+}
+
+// undeltify undeltifies an *ObjectToPack by retrieving the original object from
+// the storer and resetting it.
+func (dw *deltaSelector) undeltify(otp *ObjectToPack) error {
+	if err := dw.restoreOriginal(otp); err != nil {
+		return err
+	}
+
+	otp.Object = otp.Original
+	otp.Depth = 0
+	return nil
+}
+
+func (dw *deltaSelector) sort(objectsToPack []*ObjectToPack) {
+	sort.Sort(byTypeAndSize(objectsToPack))
+}
+
+func (dw *deltaSelector) walk(
+	objectsToPack []*ObjectToPack,
+	packWindow uint,
+) error {
+	indexMap := make(map[plumbing.Hash]*deltaIndex)
+	for i := 0; i < len(objectsToPack); i++ {
+		// Clean up the index map and reconstructed delta objects for anything
+		// outside our pack window, to save memory.
+		if i > int(packWindow) {
+			obj := objectsToPack[i-int(packWindow)]
+
+			delete(indexMap, obj.Hash())
+
+			if obj.IsDelta() {
+				obj.SaveOriginalMetadata()
+				obj.CleanOriginal()
+			}
+		}
+
+		target := objectsToPack[i]
+
+		// If we already have a delta, we don't try to find a new one for this
+		// object. This happens when a delta is set to be reused from an existing
+		// packfile.
+		if target.IsDelta() {
+			continue
+		}
+
+		// We only want to create deltas from specific types.
+		if !applyDelta[target.Type()] {
+			continue
+		}
+
+		for j := i - 1; j >= 0 && i-j < int(packWindow); j-- {
+			base := objectsToPack[j]
+			// Objects must use only the same type as their delta base.
+			// Since objectsToPack is sorted by type and size, once we find
+			// a different type, we know we won't find more of them.
+			if base.Type() != target.Type() {
+				break
+			}
+
+			if err := dw.tryToDeltify(indexMap, base, target); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func (dw *deltaSelector) tryToDeltify(indexMap map[plumbing.Hash]*deltaIndex, base, target *ObjectToPack) error {
+	// Original object might not be present if we're reusing a delta, so we
+	// ensure it is restored.
+	if err := dw.restoreOriginal(target); err != nil {
+		return err
+	}
+
+	if err := dw.restoreOriginal(base); err != nil {
+		return err
+	}
+
+	// If the sizes are radically different, this is a bad pairing.
+	if target.Size() < base.Size()>>4 {
+		return nil
+	}
+
+	msz := dw.deltaSizeLimit(
+		target.Object.Size(),
+		base.Depth,
+		target.Depth,
+		target.IsDelta(),
+	)
+
+	// Nearly impossible to fit useful delta.
+	if msz <= 8 {
+		return nil
+	}
+
+	// If we have to insert a lot to make this work, find another.
+	if base.Size()-target.Size() > msz {
+		return nil
+	}
+
+	if _, ok := indexMap[base.Hash()]; !ok {
+		indexMap[base.Hash()] = new(deltaIndex)
+	}
+
+	// Now we can generate the delta using originals
+	delta, err := getDelta(indexMap[base.Hash()], base.Original, target.Original)
+	if err != nil {
+		return err
+	}
+
+	// if delta better than target
+	if delta.Size() < msz {
+		target.SetDelta(base, delta)
+	}
+
+	return nil
+}
+
+func (dw *deltaSelector) deltaSizeLimit(targetSize int64, baseDepth int,
+	targetDepth int, targetDelta bool) int64 {
+	if !targetDelta {
+		// Any delta should be no more than 50% of the original size
+		// (for text files deflate of whole form should shrink 50%).
+		n := targetSize >> 1
+
+		// Evenly distribute delta size limits over allowed depth.
+		// If src is non-delta (depth = 0), delta <= 50% of original.
+		// If src is almost at limit (9/10), delta <= 10% of original.
+		return n * (maxDepth - int64(baseDepth)) / maxDepth
+	}
+
+	// With a delta base chosen any new delta must be "better".
+	// Retain the distribution described above.
+	d := int64(targetDepth)
+	n := targetSize
+
+	// If target depth is bigger than maxDepth, this delta is not suitable to be used.
+	if d >= maxDepth {
+		return 0
+	}
+
+	// If src is whole (depth=0) and base is near limit (depth=9/10)
+	// any delta using src can be 10x larger and still be better.
+	//
+	// If src is near limit (depth=9/10) and base is whole (depth=0)
+	// a new delta dependent on src must be 1/10th the size.
+	return n * (maxDepth - int64(baseDepth)) / (maxDepth - d)
+}
+
+type byTypeAndSize []*ObjectToPack
+
+func (a byTypeAndSize) Len() int { return len(a) }
+
+func (a byTypeAndSize) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+func (a byTypeAndSize) Less(i, j int) bool {
+	if a[i].Type() < a[j].Type() {
+		return false
+	}
+
+	if a[i].Type() > a[j].Type() {
+		return true
+	}
+
+	return a[i].Size() > a[j].Size()
+}

vendor/github.com/go-git/go-git/v5/plumbing/format/packfile/diff_delta.go

@@ -0,0 +1,204 @@
+package packfile
+
+import (
+	"bytes"
+
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/utils/ioutil"
+	"github.com/go-git/go-git/v5/utils/sync"
+)
+
+// See https://github.com/jelmer/dulwich/blob/master/dulwich/pack.py and
+// https://github.com/tarruda/node-git-core/blob/master/src/js/delta.js
+// for more info
+
+const (
+	// Standard chunk size used to generate fingerprints
+	s = 16
+
+	// https://github.com/git/git/blob/f7466e94375b3be27f229c78873f0acf8301c0a5/diff-delta.c#L428
+	// Max size of a copy operation (64KB).
+	maxCopySize = 64 * 1024
+
+	// Min size of a copy operation.
+	minCopySize = 4
+)
+
+// GetDelta returns an EncodedObject of type OFSDeltaObject. Base and Target object,
+// will be loaded into memory to be able to create the delta object.
+// To generate target again, you will need the obtained object and "base" one.
+// Error will be returned if base or target object cannot be read.
+func GetDelta(base, target plumbing.EncodedObject) (plumbing.EncodedObject, error) {
+	return getDelta(new(deltaIndex), base, target)
+}
+
+func getDelta(index *deltaIndex, base, target plumbing.EncodedObject) (o plumbing.EncodedObject, err error) {
+	br, err := base.Reader()
+	if err != nil {
+		return nil, err
+	}
+
+	defer ioutil.CheckClose(br, &err)
+
+	tr, err := target.Reader()
+	if err != nil {
+		return nil, err
+	}
+
+	defer ioutil.CheckClose(tr, &err)
+
+	bb := sync.GetBytesBuffer()
+	defer sync.PutBytesBuffer(bb)
+
+	_, err = bb.ReadFrom(br)
+	if err != nil {
+		return nil, err
+	}
+
+	tb := sync.GetBytesBuffer()
+	defer sync.PutBytesBuffer(tb)
+
+	_, err = tb.ReadFrom(tr)
+	if err != nil {
+		return nil, err
+	}
+
+	db := diffDelta(index, bb.Bytes(), tb.Bytes())
+	delta := &plumbing.MemoryObject{}
+	_, err = delta.Write(db)
+	if err != nil {
+		return nil, err
+	}
+
+	delta.SetSize(int64(len(db)))
+	delta.SetType(plumbing.OFSDeltaObject)
+
+	return delta, nil
+}
+
+// DiffDelta returns the delta that transforms src into tgt.
+func DiffDelta(src, tgt []byte) []byte {
+	return diffDelta(new(deltaIndex), src, tgt)
+}
+
+func diffDelta(index *deltaIndex, src []byte, tgt []byte) []byte {
+	buf := sync.GetBytesBuffer()
+	defer sync.PutBytesBuffer(buf)
+	buf.Write(deltaEncodeSize(len(src)))
+	buf.Write(deltaEncodeSize(len(tgt)))
+
+	if len(index.entries) == 0 {
+		index.init(src)
+	}
+
+	ibuf := sync.GetBytesBuffer()
+	defer sync.PutBytesBuffer(ibuf)
+	for i := 0; i < len(tgt); i++ {
+		offset, l := index.findMatch(src, tgt, i)
+
+		if l == 0 {
+			// couldn't find a match, just write the current byte and continue
+			ibuf.WriteByte(tgt[i])
+		} else if l < 0 {
+			// src is less than blksz, copy the rest of the target to avoid
+			// calls to findMatch
+			for ; i < len(tgt); i++ {
+				ibuf.WriteByte(tgt[i])
+			}
+		} else if l < s {
+			// remaining target is less than blksz, copy what's left of it
+			// and avoid calls to findMatch
+			for j := i; j < i+l; j++ {
+				ibuf.WriteByte(tgt[j])
+			}
+			i += l - 1
+		} else {
+			encodeInsertOperation(ibuf, buf)
+
+			rl := l
+			aOffset := offset
+			for rl > 0 {
+				if rl < maxCopySize {
+					buf.Write(encodeCopyOperation(aOffset, rl))
+					break
+				}
+
+				buf.Write(encodeCopyOperation(aOffset, maxCopySize))
+				rl -= maxCopySize
+				aOffset += maxCopySize
+			}
+
+			i += l - 1
+		}
+	}
+
+	encodeInsertOperation(ibuf, buf)
+
+	// buf.Bytes() is only valid until the next modifying operation on the buffer. Copy it.
+	return append([]byte{}, buf.Bytes()...)
+}
+
+func encodeInsertOperation(ibuf, buf *bytes.Buffer) {
+	if ibuf.Len() == 0 {
+		return
+	}
+
+	b := ibuf.Bytes()
+	s := ibuf.Len()
+	o := 0
+	for {
+		if s <= 127 {
+			break
+		}
+		buf.WriteByte(byte(127))
+		buf.Write(b[o : o+127])
+		s -= 127
+		o += 127
+	}
+	buf.WriteByte(byte(s))
+	buf.Write(b[o : o+s])
+
+	ibuf.Reset()
+}
+
+func deltaEncodeSize(size int) []byte {
+	var ret []byte
+	c := size & 0x7f
+	size >>= 7
+	for {
+		if size == 0 {
+			break
+		}
+
+		ret = append(ret, byte(c|0x80))
+		c = size & 0x7f
+		size >>= 7
+	}
+	ret = append(ret, byte(c))
+
+	return ret
+}
+
+func encodeCopyOperation(offset, length int) []byte {
+	code := 0x80
+	var opcodes []byte
+
+	var i uint
+	for i = 0; i < 4; i++ {
+		f := 0xff << (i * 8)
+		if offset&f != 0 {
+			opcodes = append(opcodes, byte(offset&f>>(i*8)))
+			code |= 0x01 << i
+		}
+	}
+
+	for i = 0; i < 3; i++ {
+		f := 0xff << (i * 8)
+		if length&f != 0 {
+			opcodes = append(opcodes, byte(length&f>>(i*8)))
+			code |= 0x10 << i
+		}
+	}
+
+	return append([]byte{byte(code)}, opcodes...)
+}