1 files changed, 110 insertions, 0 deletions
diff --git a/modules/assetfs/layered_test.go b/modules/assetfs/layered_test.go
new file mode 100644
index 0000000..58876d9
--- /dev/null
+++ b/modules/assetfs/layered_test.go
@@ -0,0 +1,110 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package assetfs
+
+import (
+	"io"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestLayered(t *testing.T) {
+	dir := filepath.Join(t.TempDir(), "assetfs-layers")
+	dir1 := filepath.Join(dir, "l1")
+	dir2 := filepath.Join(dir, "l2")
+
+	mkdir := func(elems ...string) {
+		require.NoError(t, os.MkdirAll(filepath.Join(elems...), 0o755))
+	}
+	write := func(content string, elems ...string) {
+		require.NoError(t, os.WriteFile(filepath.Join(elems...), []byte(content), 0o644))
+	}
+
+	// d1 & f1: only in "l1"; d2 & f2: only in "l2"
+	// da & fa: in both "l1" and "l2"
+	mkdir(dir1, "d1")
+	mkdir(dir1, "da")
+	mkdir(dir1, "da/sub1")
+
+	mkdir(dir2, "d2")
+	mkdir(dir2, "da")
+	mkdir(dir2, "da/sub2")
+
+	write("dummy", dir1, ".DS_Store")
+	write("f1", dir1, "f1")
+	write("fa-1", dir1, "fa")
+	write("d1-f", dir1, "d1/f")
+	write("da-f-1", dir1, "da/f")
+
+	write("f2", dir2, "f2")
+	write("fa-2", dir2, "fa")
+	write("d2-f", dir2, "d2/f")
+	write("da-f-2", dir2, "da/f")
+
+	assets := Layered(Local("l1", dir1), Local("l2", dir2))
+
+	f, err := assets.Open("f1")
+	require.NoError(t, err)
+	bs, err := io.ReadAll(f)
+	require.NoError(t, err)
+	assert.EqualValues(t, "f1", string(bs))
+	_ = f.Close()
+
+	assertRead := func(expected string, expectedErr error, elems ...string) {
+		bs, err := assets.ReadFile(elems...)
+		if err != nil {
+			require.ErrorIs(t, err, expectedErr)
+		} else {
+			require.NoError(t, err)
+			assert.Equal(t, expected, string(bs))
+		}
+	}
+	assertRead("f1", nil, "f1")
+	assertRead("f2", nil, "f2")
+	assertRead("fa-1", nil, "fa")
+
+	assertRead("d1-f", nil, "d1/f")
+	assertRead("d2-f", nil, "d2/f")
+	assertRead("da-f-1", nil, "da/f")
+
+	assertRead("", fs.ErrNotExist, "no-such")
+
+	files, err := assets.ListFiles(".", true)
+	require.NoError(t, err)
+	assert.EqualValues(t, []string{"f1", "f2", "fa"}, files)
+
+	files, err = assets.ListFiles(".", false)
+	require.NoError(t, err)
+	assert.EqualValues(t, []string{"d1", "d2", "da"}, files)
+
+	files, err = assets.ListFiles(".")
+	require.NoError(t, err)
+	assert.EqualValues(t, []string{"d1", "d2", "da", "f1", "f2", "fa"}, files)
+
+	files, err = assets.ListAllFiles(".", true)
+	require.NoError(t, err)
+	assert.EqualValues(t, []string{"d1/f", "d2/f", "da/f", "f1", "f2", "fa"}, files)
+
+	files, err = assets.ListAllFiles(".", false)
+	require.NoError(t, err)
+	assert.EqualValues(t, []string{"d1", "d2", "da", "da/sub1", "da/sub2"}, files)
+
+	files, err = assets.ListAllFiles(".")
+	require.NoError(t, err)
+	assert.EqualValues(t, []string{
+		"d1", "d1/f",
+		"d2", "d2/f",
+		"da", "da/f", "da/sub1", "da/sub2",
+		"f1", "f2", "fa",
+	}, files)
+
+	assert.Empty(t, assets.GetFileLayerName("no-such"))
+	assert.EqualValues(t, "l1", assets.GetFileLayerName("f1"))
+	assert.EqualValues(t, "l2", assets.GetFileLayerName("f2"))
+}