Add some functions for the fs package

fs/fs.go

@@ -2,7 +2,9 @@ package fs
 
 import (
 	"errors"
+	"fmt"
 	"io"
+	"io/fs"
 	"os"
 	"path/filepath"
 	"strings"
@@ -119,5 +121,32 @@ func IsSymlink(path string) (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	return fi.Mode()&os.ModeSymlink != 0, nil
+	return IsSymlinkMode(fi.Mode()), nil
+}
+
+// IsSymlinkMode check the mode is a symbolic link or not
+func IsSymlinkMode(mode fs.FileMode) bool {
+	return mode&fs.ModeSymlink != 0
+}
+
+// IsSymlinkSupported checks if the system supports symbolic links
+func IsSymlinkSupported() bool {
+	symlink := filepath.Join(os.TempDir(), "symlink_detect.symlink")
+	defer os.RemoveAll(symlink)
+	return Symlink(os.Args[0], symlink) == nil
+}
+
+// Symlink create a symbolic link
+func Symlink(oldname, newname string) error {
+	return os.Symlink(oldname, newname)
+}
+
+// Readlink returns the destination of the named symbolic link
+func Readlink(name string) (string, error) {
+	return os.Readlink(name)
+}
+
+// SymlinkText build custom symlink text content
+func SymlinkText(realPath string) string {
+	return fmt.Sprintf("# symlink\n%s", realPath)
 }

fs/fs_test.go

@@ -435,6 +435,25 @@ func TestIsSymlink(t *testing.T) {
 	}
 }
 
+func TestIsSymlinkSupported(t *testing.T) {
+	IsSymlinkSupported()
+}
+
+func TestReadlink_IsNotExistError(t *testing.T) {
+	_, err := Readlink(testNotFoundFilePath)
+	if !os.IsNotExist(err) {
+		t.Errorf("expect to get is not exist error, but actual get %v", err)
+	}
+}
+
+func TestSymlinkText(t *testing.T) {
+	expect := "# symlink\n/etc/profile"
+	actual := SymlinkText("/etc/profile")
+	if expect != actual {
+		t.Errorf("TestSymlinkText error, expect get %s, but actual get %s", expect, actual)
+	}
+}
+
 func isNotExistAlwaysFalseMock(err error) bool {
 	return false
 }