ntool/ncli/cmdline/builder.go

package cmdline

import (
	"git.noahlan.cn/noahlan/ntool/nstr"
	"strings"
)

// LineBuilder build command line string.
// codes refer from strings.Builder
type LineBuilder struct {
	strings.Builder
}

// NewBuilder create
func NewBuilder(binFile string, args ...string) *LineBuilder {
	b := &LineBuilder{}

	if binFile != "" {
		b.AddArg(binFile)
	}

	b.AddArray(args)
	return b
}

// AddArg to builder
func (b *LineBuilder) AddArg(arg string) {
	_, _ = b.WriteString(arg)
}

// AddArgs to builder
func (b *LineBuilder) AddArgs(args ...string) {
	b.AddArray(args)
}

// AddArray to builder
func (b *LineBuilder) AddArray(args []string) {
	for _, arg := range args {
		_, _ = b.WriteString(arg)
	}
}

// AddAny args to builder
func (b *LineBuilder) AddAny(args ...any) {
	for _, arg := range args {
		_, _ = b.WriteString(nstr.SafeString(arg))
	}
}

// WriteString arg string to the builder, will auto quote special string.
// refer strconv.Quote()
func (b *LineBuilder) WriteString(a string) (int, error) {
	var quote byte
	if pos := strings.IndexByte(a, '"'); pos > -1 {
		quote = '\''
		// fix: a = `--pretty=format:"one two three"`
		if pos > 0 && '"' == a[len(a)-1] {
			quote = 0
		}
	} else if pos := strings.IndexByte(a, '\''); pos > -1 {
		quote = '"'
		// fix: a = "--pretty=format:'one two three'"
		if pos > 0 && '\'' == a[len(a)-1] {
			quote = 0
		}
	} else if a == "" || strings.ContainsRune(a, ' ') {
		quote = '"'
	}

	// add sep on not-first write.
	if b.Len() != 0 {
		_ = b.WriteByte(' ')
	}

	// no quote char OR not need quote
	if quote == 0 {
		return b.Builder.WriteString(a)
	}

	_ = b.WriteByte(quote) // add start quote
	n, err := b.Builder.WriteString(a)
	_ = b.WriteByte(quote) // add end quote
	return n, err
}