forked from toolshed/abra
		
	
		
			
				
	
	
		
			82 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| //go:build !windows && !js && !appengine
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| // +build !windows,!js,!appengine
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| 
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| package runewidth
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| 
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| import (
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| 	"os"
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| 	"regexp"
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| 	"strings"
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| )
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| 
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| var reLoc = regexp.MustCompile(`^[a-z][a-z][a-z]?(?:_[A-Z][A-Z])?\.(.+)`)
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| 
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| var mblenTable = map[string]int{
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| 	"utf-8":   6,
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| 	"utf8":    6,
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| 	"jis":     8,
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| 	"eucjp":   3,
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| 	"euckr":   2,
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| 	"euccn":   2,
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| 	"sjis":    2,
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| 	"cp932":   2,
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| 	"cp51932": 2,
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| 	"cp936":   2,
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| 	"cp949":   2,
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| 	"cp950":   2,
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| 	"big5":    2,
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| 	"gbk":     2,
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| 	"gb2312":  2,
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| }
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| 
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| func isEastAsian(locale string) bool {
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| 	charset := strings.ToLower(locale)
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| 	r := reLoc.FindStringSubmatch(locale)
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| 	if len(r) == 2 {
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| 		charset = strings.ToLower(r[1])
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| 	}
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| 
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| 	if strings.HasSuffix(charset, "@cjk_narrow") {
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| 		return false
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| 	}
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| 
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| 	for pos, b := range []byte(charset) {
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| 		if b == '@' {
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| 			charset = charset[:pos]
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| 			break
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| 		}
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| 	}
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| 	max := 1
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| 	if m, ok := mblenTable[charset]; ok {
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| 		max = m
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| 	}
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| 	if max > 1 && (charset[0] != 'u' ||
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| 		strings.HasPrefix(locale, "ja") ||
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| 		strings.HasPrefix(locale, "ko") ||
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| 		strings.HasPrefix(locale, "zh")) {
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| 		return true
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| 	}
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| 	return false
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| }
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| 
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| // IsEastAsian return true if the current locale is CJK
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| func IsEastAsian() bool {
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| 	locale := os.Getenv("LC_ALL")
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| 	if locale == "" {
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| 		locale = os.Getenv("LC_CTYPE")
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| 	}
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| 	if locale == "" {
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| 		locale = os.Getenv("LANG")
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| 	}
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| 
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| 	// ignore C locale
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| 	if locale == "POSIX" || locale == "C" {
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| 		return false
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| 	}
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| 	if len(locale) > 1 && locale[0] == 'C' && (locale[1] == '.' || locale[1] == '-') {
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| 		return false
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| 	}
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| 
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| 	return isEastAsian(locale)
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| }
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