operations: fix rmdirs failing on directories which only look empty - f…

…ixes #9907 Google Drive leaves out of its listings any Google Doc it has no export format for, such as a .gform. rmdirs therefore saw a directory holding only such a file as empty, tried to remove it, and failed the whole run with "directory not empty". A directory which turns out not to be empty is not a failure for rmdirs, whose job is to remove the empty ones, so skip it and carry on. This also covers a file arriving between the listing and the removal. sync already ignores this error when it prunes empty directories. The drive backend reported this case as a bare error rather than fs.ErrorDirectoryNotEmpty, so it now returns the standard error like the other backends, which is what makes it recognisable here.
Karthikvanabhojana1 · Sep 30, 2026 · Sep 30, 2026 · 4b54841962255a92043c1f3740ea23f8bc92caff
commit 4b54841962255a92043c1f3740ea23f8bc92caff
@@ -2784,7 +2784,7 @@ func (f *Fs) purgeCheck(ctx context.Context, dir string, check bool) error {
 			return err
 		}
 		if found {
-			return fmt.Errorf("directory not empty")
+			return fs.ErrorDirectoryNotEmpty
 		}
 	}
 	if root != "" {

@@ -1601,6 +1601,14 @@ func Rmdirs(ctx context.Context, f fs.Fs, dir string, leaveRoot bool) error {
 			dir := dir
 			g.Go(func() error {
 				err := TryRmdir(gCtx, f, dir)
+				if errors.Is(err, fs.ErrorDirectoryNotEmpty) {
+					// The listing above showed this directory as empty but the
+					// backend disagrees, either because it hides some files from
+					// listings or because something was written in the meantime.
+					// Leaving it in place is what was asked for.
+					fs.Infof(dir, "Not removing directory as it is not empty")
+					return nil
+				}
 				if err != nil {
 					err = fs.CountError(ctx, err)
 					fs.Errorf(dir, "Failed to rmdir: %v", err)

@@ -815,6 +815,41 @@ func TestRmdirsWithFilter(t *testing.T) {
 	)
 }
 
+// dirNotEmptyFs is an Fs whose directories always refuse to be removed,
+// standing in for a backend which hides some files from its listings.
+type dirNotEmptyFs struct {
+	fs.Fs
+}
+
+// Rmdir reports the directory as not empty
+func (f dirNotEmptyFs) Rmdir(ctx context.Context, dir string) error {
+	return fs.ErrorDirectoryNotEmpty
+}
+
+func TestRmdirsDirectoryNotEmpty(t *testing.T) {
+	ctx := context.Background()
+	r := fstest.NewRun(t)
+	r.Mkdir(ctx, r.Fremote)
+
+	r.ForceMkdir(ctx, r.Fremote)
+
+	require.NoError(t, operations.Mkdir(ctx, r.Fremote, "A1"))
+
+	accounting.Stats(ctx).ResetErrors()
+	require.NoError(t, operations.Rmdirs(ctx, dirNotEmptyFs{r.Fremote}, "", false))
+	assert.Equal(t, int64(0), accounting.Stats(ctx).GetErrors())
+
+	fstest.CheckListingWithPrecision(
+		t,
+		r.Fremote,
+		[]fstest.Item{},
+		[]string{
+			"A1",
+		},
+		fs.GetModifyWindow(ctx, r.Fremote),
+	)
+}
+
 func TestCopyURL(t *testing.T) {
 	ctx := context.Background()
 	ctx, ci := fs.AddConfig(ctx)