code review 6257059: path/filepath: implement documented SkipDir behavior

src/pkg/path/filepath/path.go

 // Copyright 2009 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 filepath implements utility routines for manipulating filename paths
 // in a way compatible with the target operating system-defined file paths.
 package filepath
 
 import (
         "errors"
@@ skipping 302 matching lines @@
         if !info.IsDir() {
                 return nil
         }
 
         list, err := readDir(path)
         if err != nil {
                 return walkFn(path, info, err)
         }
 
         for _, fileInfo := range list {
-                if err = walk(Join(path, fileInfo.Name()), fileInfo, walkFn); err != nil && err != SkipDir {
-                        return err
+                err = walk(Join(path, fileInfo.Name()), fileInfo, walkFn)
+                if err != nil {
+                        if !fileInfo.IsDir() || err != SkipDir {
+                                return err
+                        }
                 }
         }
         return nil
 }
 
 // Walk walks the file tree rooted at root, calling walkFn for each file or
 // directory in the tree, including root. All errors that arise visiting files
 // and directories are filtered by walkFn. The files are walked in lexical
 // order, which makes the output deterministic but means that for very
 // large directories Walk can be inefficient.
@@ skipping 72 matching lines @@
         dir := Clean(path[len(vol) : i+1])
         last := len(dir) - 1
         if last > 0 && os.IsPathSeparator(dir[last]) {
                 dir = dir[:last]
         }
         if dir == "" {
                 dir = "."
         }
         return vol + dir
 }