copygo122_test.go

//go:build go1.22 && !go1.23

// Copyright 2016 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 tagliatelle_test

import (
	"io"
	"io/fs"
	"os"
	"path/filepath"
)

// CopyFS IMPORTANT:
// This is a modified copy of os.CopyFS.
// os.CopyFS is available in go1.23.
// TODO(ldez) remove this file when bump to go1.23.
//
//nolint:all // code from Go.
func CopyFS(dir string, fsys fs.FS) error {
	return fs.WalkDir(fsys, ".", func(path string, d fs.DirEntry, err error) error {
		if err != nil {
			return err
		}

		fpath := path

		newPath := filepath.Join(dir, fpath)
		if d.IsDir() {
			return os.MkdirAll(newPath, 0777)
		}

		// TODO(panjf2000): handle symlinks with the help of fs.ReadLinkFS
		// 		once https://go.dev/issue/49580 is done.
		//		we also need filepathlite.IsLocal from https://go.dev/cl/564295.
		if !d.Type().IsRegular() {
			return &os.PathError{Op: "CopyFS", Path: path, Err: os.ErrInvalid}
		}

		r, err := fsys.Open(path)
		if err != nil {
			return err
		}
		defer r.Close()
		info, err := r.Stat()
		if err != nil {
			return err
		}
		w, err := os.OpenFile(newPath, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0666|info.Mode()&0777)
		if err != nil {
			return err
		}

		if _, err := io.Copy(w, r); err != nil {
			w.Close()
			return &os.PathError{Op: "Copy", Path: newPath, Err: err}
		}
		return w.Close()
	})
}