templates: deprecate NewParse()

It it just a chain of `New("sometag").Parse(...)`, and most of our
uses don't use a tag for the template, so can call Parse.

There's no public users of this function, but deprecating it first
just in case.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/container/list.go

@@ -82,7 +82,7 @@ func buildContainerListOptions(options *psOptions) (*container.ListOptions, erro
 
 	// always validate template when `--format` is used, for consistency
 	if len(options.format) > 0 {
-		tmpl, err := templates.NewParse("", options.format)
+		tmpl, err := templates.Parse(options.format)
 		if err != nil {
 			return nil, errors.Wrap(err, "failed to parse template")
 		}

cli/command/system/info.go

@@ -162,7 +162,7 @@ func needsServerInfo(template string, info dockerInfo) bool {
 	}
 
 	// A template is provided and has at least one field set.
-	tmpl, err := templates.NewParse("", template)
+	tmpl, err := templates.Parse(template)
 	if err != nil {
 		// ignore parsing errors here, and let regular code handle them
 		return true

cli/command/system/version.go

@@ -209,8 +209,7 @@ func newVersionTemplate(templateFormat string) (*template.Template, error) {
 	case formatter.JSONFormatKey:
 		templateFormat = formatter.JSONFormat
 	}
-	tmpl := templates.New("version").Funcs(template.FuncMap{"getDetailsOrder": getDetailsOrder})
-	tmpl, err := tmpl.Parse(templateFormat)
+	tmpl, err := templates.New("version").Funcs(template.FuncMap{"getDetailsOrder": getDetailsOrder}).Parse(templateFormat)
 	if err != nil {
 		return nil, errors.Wrap(err, "template parsing error")
 	}