path/filepath: reuse os.ReadDir

While reading the source code, I noticed that readDir
seemed extremely similar to os.ReadDir. They indeed appear to be copies.

Note that there's readDirNames as well, but it has no corresponding
os.ReadDirNames top-level helper to be replaced by.

Change-Id: I6fe1d0aeda35dc69bb4531986fe3a21ebda1d877
Reviewed-on: https://go-review.googlesource.com/c/go/+/530795
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

1 files changed, 1 insertions, 17 deletions

diff --git a/src/path/filepath/path.go b/src/path/filepath/path.go
index 6dcb0e1fb9..b1f1bf0e3f 100644
--- a/src/path/filepath/path.go
+++ b/src/path/filepath/path.go
@@ -463,7 +463,7 @@ func walkDir(path string, d fs.DirEntry, walkDirFn fs.WalkDirFunc) error {
 		return err
 	}
 
-	dirs, err := readDir(path)
+	dirs, err := os.ReadDir(path)
 	if err != nil {
 		// Second call, to report ReadDir error.
 		err = walkDirFn(path, d, err)
@@ -580,22 +580,6 @@ func Walk(root string, fn WalkFunc) error {
 	return err
 }
 
-// readDir reads the directory named by dirname and returns
-// a sorted list of directory entries.
-func readDir(dirname string) ([]fs.DirEntry, error) {
-	f, err := os.Open(dirname)
-	if err != nil {
-		return nil, err
-	}
-	dirs, err := f.ReadDir(-1)
-	f.Close()
-	if err != nil {
-		return nil, err
-	}
-	sort.Slice(dirs, func(i, j int) bool { return dirs[i].Name() < dirs[j].Name() })
-	return dirs, nil
-}
-
 // readDirNames reads the directory named by dirname and returns
 // a sorted list of directory entry names.
 func readDirNames(dirname string) ([]string, error) {