Add file tree to file view page (#32721)

Resolve #29328

This pull request introduces a file tree on the left side when reviewing
files of a repository.

---------

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

3 files changed, 163 insertions, 11 deletions

diff --git a/services/contexttest/context_tests.go b/services/contexttest/context_tests.go
index 98b8bdd63e..c895de3569 100644
--- a/services/contexttest/context_tests.go
+++ b/services/contexttest/context_tests.go
@@ -20,6 +20,7 @@ import (
 	"code.gitea.io/gitea/models/unittest"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/cache"
+	git_module "code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/reqctx"
 	"code.gitea.io/gitea/modules/session"
@@ -30,6 +31,7 @@ import (
 
 	"github.com/go-chi/chi/v5"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func mockRequest(t *testing.T, reqPath string) *http.Request {
@@ -85,7 +87,7 @@ func MockAPIContext(t *testing.T, reqPath string) (*context.APIContext, *httptes
 	base := context.NewBaseContext(resp, req)
 	base.Data = middleware.GetContextData(req.Context())
 	base.Locale = &translation.MockLocale{}
-	ctx := &context.APIContext{Base: base}
+	ctx := &context.APIContext{Base: base, Repo: &context.Repository{}}
 	chiCtx := chi.NewRouteContext()
 	ctx.SetContextValue(chi.RouteCtxKey, chiCtx)
 	return ctx, resp
@@ -106,13 +108,13 @@ func MockPrivateContext(t *testing.T, reqPath string) (*context.PrivateContext,
 // LoadRepo load a repo into a test context.
 func LoadRepo(t *testing.T, ctx gocontext.Context, repoID int64) {
 	var doer *user_model.User
-	repo := &context.Repository{}
+	var repo *context.Repository
 	switch ctx := ctx.(type) {
 	case *context.Context:
-		ctx.Repo = repo
+		repo = ctx.Repo
 		doer = ctx.Doer
 	case *context.APIContext:
-		ctx.Repo = repo
+		repo = ctx.Repo
 		doer = ctx.Doer
 	default:
 		assert.FailNow(t, "context is not *context.Context or *context.APIContext")
@@ -140,15 +142,17 @@ func LoadRepoCommit(t *testing.T, ctx gocontext.Context) {
 	}
 
 	gitRepo, err := gitrepo.OpenRepository(ctx, repo.Repository)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 	defer gitRepo.Close()
-	branch, err := gitRepo.GetHEADBranch()
-	assert.NoError(t, err)
-	assert.NotNil(t, branch)
-	if branch != nil {
-		repo.Commit, err = gitRepo.GetBranchCommit(branch.Name)
-		assert.NoError(t, err)
+
+	if repo.RefFullName == "" {
+		repo.RefFullName = git_module.RefNameFromBranch(repo.Repository.DefaultBranch)
+	}
+	if repo.RefFullName.IsPull() {
+		repo.BranchName = repo.RefFullName.ShortName()
 	}
+	repo.Commit, err = gitRepo.GetCommit(repo.RefFullName.String())
+	require.NoError(t, err)
 }
 
 // LoadUser load a user into a test context
diff --git a/services/repository/files/tree.go b/services/repository/files/tree.go
index 6775186afd..9142416347 100644
--- a/services/repository/files/tree.go
+++ b/services/repository/files/tree.go
@@ -7,9 +7,13 @@ import (
 	"context"
 	"fmt"
 	"net/url"
+	"path"
+	"sort"
+	"strings"
 
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/util"
@@ -118,3 +122,98 @@ func GetTreeBySHA(ctx context.Context, repo *repo_model.Repository, gitRepo *git
 	}
 	return tree, nil
 }
+
+func entryModeString(entryMode git.EntryMode) string {
+	switch entryMode {
+	case git.EntryModeBlob:
+		return "blob"
+	case git.EntryModeExec:
+		return "exec"
+	case git.EntryModeSymlink:
+		return "symlink"
+	case git.EntryModeCommit:
+		return "commit" // submodule
+	case git.EntryModeTree:
+		return "tree"
+	}
+	return "unknown"
+}
+
+type TreeViewNode struct {
+	EntryName    string          `json:"entryName"`
+	EntryMode    string          `json:"entryMode"`
+	FullPath     string          `json:"fullPath"`
+	SubmoduleURL string          `json:"submoduleUrl,omitempty"`
+	Children     []*TreeViewNode `json:"children,omitempty"`
+}
+
+func (node *TreeViewNode) sortLevel() int {
+	return util.Iif(node.EntryMode == "tree" || node.EntryMode == "commit", 0, 1)
+}
+
+func newTreeViewNodeFromEntry(ctx context.Context, commit *git.Commit, parentDir string, entry *git.TreeEntry) *TreeViewNode {
+	node := &TreeViewNode{
+		EntryName: entry.Name(),
+		EntryMode: entryModeString(entry.Mode()),
+		FullPath:  path.Join(parentDir, entry.Name()),
+	}
+
+	if node.EntryMode == "commit" {
+		if subModule, err := commit.GetSubModule(node.FullPath); err != nil {
+			log.Error("GetSubModule: %v", err)
+		} else if subModule != nil {
+			submoduleFile := git.NewCommitSubmoduleFile(subModule.URL, entry.ID.String())
+			webLink := submoduleFile.SubmoduleWebLink(ctx)
+			node.SubmoduleURL = webLink.CommitWebLink
+		}
+	}
+
+	return node
+}
+
+// sortTreeViewNodes list directory first and with alpha sequence
+func sortTreeViewNodes(nodes []*TreeViewNode) {
+	sort.Slice(nodes, func(i, j int) bool {
+		a, b := nodes[i].sortLevel(), nodes[j].sortLevel()
+		if a != b {
+			return a < b
+		}
+		return nodes[i].EntryName < nodes[j].EntryName
+	})
+}
+
+func listTreeNodes(ctx context.Context, commit *git.Commit, tree *git.Tree, treePath, subPath string) ([]*TreeViewNode, error) {
+	entries, err := tree.ListEntries()
+	if err != nil {
+		return nil, err
+	}
+
+	subPathDirName, subPathRemaining, _ := strings.Cut(subPath, "/")
+	nodes := make([]*TreeViewNode, 0, len(entries))
+	for _, entry := range entries {
+		node := newTreeViewNodeFromEntry(ctx, commit, treePath, entry)
+		nodes = append(nodes, node)
+		if entry.IsDir() && subPathDirName == entry.Name() {
+			subTreePath := treePath + "/" + node.EntryName
+			if subTreePath[0] == '/' {
+				subTreePath = subTreePath[1:]
+			}
+			subNodes, err := listTreeNodes(ctx, commit, entry.Tree(), subTreePath, subPathRemaining)
+			if err != nil {
+				log.Error("listTreeNodes: %v", err)
+			} else {
+				node.Children = subNodes
+			}
+		}
+	}
+	sortTreeViewNodes(nodes)
+	return nodes, nil
+}
+
+func GetTreeViewNodes(ctx context.Context, commit *git.Commit, treePath, subPath string) ([]*TreeViewNode, error) {
+	entry, err := commit.GetTreeEntryByPath(treePath)
+	if err != nil {
+		return nil, err
+	}
+	return listTreeNodes(ctx, commit, entry.Tree(), treePath, subPath)
+}
diff --git a/services/repository/files/tree_test.go b/services/repository/files/tree_test.go
index 0c60fddf7b..8ea54969ce 100644
--- a/services/repository/files/tree_test.go
+++ b/services/repository/files/tree_test.go
@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/git"
 	api "code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/services/contexttest"
 
@@ -50,3 +51,51 @@ func TestGetTreeBySHA(t *testing.T) {
 
 	assert.EqualValues(t, expectedTree, tree)
 }
+
+func TestGetTreeViewNodes(t *testing.T) {
+	unittest.PrepareTestEnv(t)
+	ctx, _ := contexttest.MockContext(t, "user2/repo1")
+	ctx.Repo.RefFullName = git.RefNameFromBranch("sub-home-md-img-check")
+	contexttest.LoadRepo(t, ctx, 1)
+	contexttest.LoadRepoCommit(t, ctx)
+	contexttest.LoadUser(t, ctx, 2)
+	contexttest.LoadGitRepo(t, ctx)
+	defer ctx.Repo.GitRepo.Close()
+
+	treeNodes, err := GetTreeViewNodes(ctx, ctx.Repo.Commit, "", "")
+	assert.NoError(t, err)
+	assert.Equal(t, []*TreeViewNode{
+		{
+			EntryName: "docs",
+			EntryMode: "tree",
+			FullPath:  "docs",
+		},
+	}, treeNodes)
+
+	treeNodes, err = GetTreeViewNodes(ctx, ctx.Repo.Commit, "", "docs/README.md")
+	assert.NoError(t, err)
+	assert.Equal(t, []*TreeViewNode{
+		{
+			EntryName: "docs",
+			EntryMode: "tree",
+			FullPath:  "docs",
+			Children: []*TreeViewNode{
+				{
+					EntryName: "README.md",
+					EntryMode: "blob",
+					FullPath:  "docs/README.md",
+				},
+			},
+		},
+	}, treeNodes)
+
+	treeNodes, err = GetTreeViewNodes(ctx, ctx.Repo.Commit, "docs", "README.md")
+	assert.NoError(t, err)
+	assert.Equal(t, []*TreeViewNode{
+		{
+			EntryName: "README.md",
+			EntryMode: "blob",
+			FullPath:  "docs/README.md",
+		},
+	}, treeNodes)
+}