Refactor "dump" sub-command (#30240)

Major changes:

* Move some functions like "addReader" / "isSubDir" /
"addRecursiveExclude" to a separate package, and add tests
* Clarify the filename&dump type logic and add tests
* Clarify the logger behavior and remove FIXME comments

Co-authored-by: Giteabot <teabot@gitea.io>

modules/dump/dumper_test.go

@@ -0,0 +1,113 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package dump
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"testing"
+	"time"
+
+	"code.gitea.io/gitea/modules/timeutil"
+
+	"github.com/mholt/archiver/v3"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPrepareFileNameAndType(t *testing.T) {
+	defer timeutil.MockSet(time.Unix(1234, 0))()
+	test := func(argFile, argType, expFile, expType string) {
+		outFile, outType := PrepareFileNameAndType(argFile, argType)
+		assert.Equal(t,
+			fmt.Sprintf("outFile=%s, outType=%s", expFile, expType),
+			fmt.Sprintf("outFile=%s, outType=%s", outFile, outType),
+			fmt.Sprintf("argFile=%s, argType=%s", argFile, argType),
+		)
+	}
+
+	test("", "", "gitea-dump-1234.zip", "zip")
+	test("", "tar.gz", "gitea-dump-1234.tar.gz", "tar.gz")
+	test("", "no-such", "", "")
+
+	test("-", "", "-", "zip")
+	test("-", "tar.gz", "-", "tar.gz")
+	test("-", "no-such", "", "")
+
+	test("a", "", "a", "zip")
+	test("a", "tar.gz", "a", "tar.gz")
+	test("a", "no-such", "", "")
+
+	test("a.zip", "", "a.zip", "zip")
+	test("a.zip", "tar.gz", "a.zip", "tar.gz")
+	test("a.zip", "no-such", "", "")
+
+	test("a.tar.gz", "", "a.tar.gz", "zip")
+	test("a.tar.gz", "tar.gz", "a.tar.gz", "tar.gz")
+	test("a.tar.gz", "no-such", "", "")
+}
+
+func TestIsSubDir(t *testing.T) {
+	tmpDir := t.TempDir()
+	_ = os.MkdirAll(filepath.Join(tmpDir, "include/sub"), 0o755)
+
+	isSub, err := IsSubdir(filepath.Join(tmpDir, "include"), filepath.Join(tmpDir, "include"))
+	assert.NoError(t, err)
+	assert.True(t, isSub)
+
+	isSub, err = IsSubdir(filepath.Join(tmpDir, "include"), filepath.Join(tmpDir, "include/sub"))
+	assert.NoError(t, err)
+	assert.True(t, isSub)
+
+	isSub, err = IsSubdir(filepath.Join(tmpDir, "include/sub"), filepath.Join(tmpDir, "include"))
+	assert.NoError(t, err)
+	assert.False(t, isSub)
+}
+
+type testWriter struct {
+	added []string
+}
+
+func (t *testWriter) Create(out io.Writer) error {
+	return nil
+}
+
+func (t *testWriter) Write(f archiver.File) error {
+	t.added = append(t.added, f.Name())
+	return nil
+}
+
+func (t *testWriter) Close() error {
+	return nil
+}
+
+func TestDumper(t *testing.T) {
+	sortStrings := func(s []string) []string {
+		sort.Strings(s)
+		return s
+	}
+	tmpDir := t.TempDir()
+	_ = os.MkdirAll(filepath.Join(tmpDir, "include/exclude1"), 0o755)
+	_ = os.MkdirAll(filepath.Join(tmpDir, "include/exclude2"), 0o755)
+	_ = os.MkdirAll(filepath.Join(tmpDir, "include/sub"), 0o755)
+	_ = os.WriteFile(filepath.Join(tmpDir, "include/a"), nil, 0o644)
+	_ = os.WriteFile(filepath.Join(tmpDir, "include/sub/b"), nil, 0o644)
+	_ = os.WriteFile(filepath.Join(tmpDir, "include/exclude1/a-1"), nil, 0o644)
+	_ = os.WriteFile(filepath.Join(tmpDir, "include/exclude2/a-2"), nil, 0o644)
+
+	tw := &testWriter{}
+	d := &Dumper{Writer: tw}
+	d.GlobalExcludeAbsPath(filepath.Join(tmpDir, "include/exclude1"))
+	err := d.AddRecursiveExclude("include", filepath.Join(tmpDir, "include"), []string{filepath.Join(tmpDir, "include/exclude2")})
+	assert.NoError(t, err)
+	assert.EqualValues(t, sortStrings([]string{"include/a", "include/sub", "include/sub/b"}), sortStrings(tw.added))
+
+	tw = &testWriter{}
+	d = &Dumper{Writer: tw}
+	err = d.AddRecursiveExclude("include", filepath.Join(tmpDir, "include"), nil)
+	assert.NoError(t, err)
+	assert.EqualValues(t, sortStrings([]string{"include/exclude2", "include/exclude2/a-2", "include/a", "include/sub", "include/sub/b", "include/exclude1", "include/exclude1/a-1"}), sortStrings(tw.added))
+}