2 files changed, 39 insertions, 1 deletions
diff --git a/src/testing/fstest/testfs.go b/src/testing/fstest/testfs.go
index ddb6080882..78b0b82640 100644
--- a/src/testing/fstest/testfs.go
+++ b/src/testing/fstest/testfs.go
@@ -270,7 +270,7 @@ func (t *fsTester) checkDir(dir string) {
 		}
 	}
 
-	t.checkGlob(dir, list)
+	t.checkGlob(dir, list2)
 }
 
 // formatEntry formats an fs.DirEntry into a string for error messages and comparison.
diff --git a/src/testing/fstest/testfs_test.go b/src/testing/fstest/testfs_test.go
index aefb4b3361..a48c597ff4 100644
--- a/src/testing/fstest/testfs_test.go
+++ b/src/testing/fstest/testfs_test.go
@@ -6,8 +6,10 @@ package fstest
 
 import (
 	"internal/testenv"
+	"io/fs"
 	"os"
 	"path/filepath"
+	"sort"
 	"testing"
 )
 
@@ -38,3 +40,39 @@ func TestDash(t *testing.T) {
 		t.Error(err)
 	}
 }
+
+type shuffledFS MapFS
+
+func (fsys shuffledFS) Open(name string) (fs.File, error) {
+	f, err := MapFS(fsys).Open(name)
+	if err != nil {
+		return nil, err
+	}
+	return &shuffledFile{File: f}, nil
+}
+
+type shuffledFile struct{ fs.File }
+
+func (f *shuffledFile) ReadDir(n int) ([]fs.DirEntry, error) {
+	dirents, err := f.File.(fs.ReadDirFile).ReadDir(n)
+	// Shuffle in a deterministic way, all we care about is making sure that the
+	// list of directory entries is not is the lexicographic order.
+	//
+	// We do this to make sure that the TestFS test suite is not affected by the
+	// order of directory entries.
+	sort.Slice(dirents, func(i, j int) bool {
+		return dirents[i].Name() > dirents[j].Name()
+	})
+	return dirents, err
+}
+
+func TestShuffledFS(t *testing.T) {
+	fsys := shuffledFS{
+		"tmp/one":   {Data: []byte("1")},
+		"tmp/two":   {Data: []byte("2")},
+		"tmp/three": {Data: []byte("3")},
+	}
+	if err := TestFS(fsys, "tmp/one", "tmp/two", "tmp/three"); err != nil {
+		t.Error(err)
+	}
+}