Fix FilterFS when skipping lazy parent directories

filter.go

@@ -176,6 +176,7 @@ func (fs *filterFS) Walk(ctx context.Context, target string, fn gofs.WalkDirFunc
 		includeMatchInfo patternmatcher.MatchInfo
 		excludeMatchInfo patternmatcher.MatchInfo
 		calledFn         bool
+		skipFn           bool
 	}
 
 	// used only for include/exclude handling
@@ -333,6 +334,9 @@ func (fs *filterFS) Walk(ctx context.Context, target string, fn gofs.WalkDirFunc
 				}
 			}
 			for i, parentDir := range parentDirs {
+				if parentDir.skipFn {
+					return filepath.SkipDir
+				}
 				if parentDir.calledFn {
 					continue
 				}
@@ -352,15 +356,21 @@ func (fs *filterFS) Walk(ctx context.Context, target string, fn gofs.WalkDirFunc
 				}
 				if fs.mapFn != nil {
 					result := fs.mapFn(parentStat.Path, parentStat)
-					if result == MapResultSkipDir || result == MapResultExclude {
+					if result == MapResultExclude {
 						continue
+					} else if result == MapResultSkipDir {
+						parentDirs[i].skipFn = true
+						return filepath.SkipDir
 					}
 				}
 
-				if err := fn(parentStat.Path, &DirEntryInfo{Stat: parentStat}, nil); err != nil {
+				parentDirs[i].calledFn = true
+				if err := fn(parentStat.Path, &DirEntryInfo{Stat: parentStat}, nil); err == filepath.SkipDir {
+					parentDirs[i].skipFn = true
+					return filepath.SkipDir
+				} else if err != nil {
 					return err
 				}
-				parentDirs[i].calledFn = true
 			}
 			if err := fn(stat.Path, &DirEntryInfo{Stat: stat}, nil); err != nil {
 				return err

filter_test.go

@@ -143,6 +143,30 @@ file bar/foo
 `), b.String())
 }
 
+func TestWalkerIncludeReturnSkipDir(t *testing.T) {
+	d, err := tmpDir(changeStream([]string{
+		"ADD foo dir",
+		"ADD foo/x dir",
+		"ADD foo/y dir",
+		"ADD foo/x/a.txt file",
+		"ADD foo/y/b.txt file",
+	}))
+	assert.NoError(t, err)
+	defer os.RemoveAll(d)
+
+	found := []string{}
+
+	err = Walk(context.Background(), d, &FilterOpt{
+		IncludePatterns: []string{"**/*.txt"},
+	}, func(path string, info gofs.FileInfo, err error) error {
+		found = append(found, path)
+		return filepath.SkipDir
+	})
+	assert.NoError(t, err)
+
+	assert.Equal(t, []string{"foo"}, found)
+}
+
 func TestWalkerExclude(t *testing.T) {
 	d, err := tmpDir(changeStream([]string{
 		"ADD bar file",
@@ -308,6 +332,33 @@ file includeDir/a.txt
 	assert.Equal(t, []string{"excludeDir", "includeDir", filepath.FromSlash("includeDir/a.txt")}, walked)
 }
 
+func TestWalkerMapSkipDirWithPattern(t *testing.T) {
+	d, err := tmpDir(changeStream([]string{
+		"ADD x dir",
+		"ADD x/a.txt file",
+		"ADD y dir",
+		"ADD y/b.txt file",
+	}))
+	assert.NoError(t, err)
+	defer os.RemoveAll(d)
+
+	b := &bytes.Buffer{}
+	err = Walk(context.Background(), d, &FilterOpt{
+		IncludePatterns: []string{"**/*.txt"},
+		Map: func(_ string, s *types.Stat) MapResult {
+			if filepath.Base(s.Path) == "x" {
+				return MapResultSkipDir
+			}
+			return MapResultKeep
+		},
+	}, bufWalk(b))
+	assert.NoError(t, err)
+
+	assert.Equal(t, filepath.FromSlash(`dir y
+file y/b.txt
+`), b.String())
+}
+
 func TestWalkerPermissionDenied(t *testing.T) {
 	if runtime.GOOS == "windows" {
 		t.Skip("os.Chmod not fully supported on Windows")