[GITEA] Detect file rename and show in history

- Add a indication to the file history if the file has been renamed,
this indication contains a link to browse the history of the file
further.
- Added unit testing.
- Added integration testing.
- Resolves https://codeberg.org/forgejo/forgejo/issues/1279

(cherry picked from commit 72c297521b)
(cherry picked from commit 283f964894)

Conflicts:
	options/locale/locale_en-US.ini
	https://codeberg.org/forgejo/forgejo/pulls/1550
(cherry picked from commit 7c30af7fde)
(cherry picked from commit f3be6eb269)
(cherry picked from commit 78e1755b94)
(cherry picked from commit 73799479e0)
(cherry picked from commit 938359b941)
(cherry picked from commit b168a9c081)

[GITEA] Detect file rename and show in history (squash) ctx.Locale

(cherry picked from commit 40447752ff)
(cherry picked from commit ea23594cdb)
(cherry picked from commit cdc473850c)

modules/git/commit.go

@@ -509,6 +509,62 @@ func GetCommitFileStatus(ctx context.Context, repoPath, commitID string) (*Commi
 	return fileStatus, nil
 }
 
+func parseCommitRenames(renames *[][2]string, stdout io.Reader) {
+	rd := bufio.NewReader(stdout)
+	for {
+		// Skip (R || three digits || NULL byte)
+		_, err := rd.Discard(5)
+		if err != nil {
+			if err != io.EOF {
+				log.Error("Unexpected error whilst reading from git log --name-status. Error: %v", err)
+			}
+			return
+		}
+		oldFileName, err := rd.ReadString('\x00')
+		if err != nil {
+			if err != io.EOF {
+				log.Error("Unexpected error whilst reading from git log --name-status. Error: %v", err)
+			}
+			return
+		}
+		newFileName, err := rd.ReadString('\x00')
+		if err != nil {
+			if err != io.EOF {
+				log.Error("Unexpected error whilst reading from git log --name-status. Error: %v", err)
+			}
+			return
+		}
+		oldFileName = strings.TrimSuffix(oldFileName, "\x00")
+		newFileName = strings.TrimSuffix(newFileName, "\x00")
+		*renames = append(*renames, [2]string{oldFileName, newFileName})
+	}
+}
+
+// GetCommitFileRenames returns the renames that the commit contains.
+func GetCommitFileRenames(ctx context.Context, repoPath, commitID string) ([][2]string, error) {
+	renames := [][2]string{}
+	stdout, w := io.Pipe()
+	done := make(chan struct{})
+	go func() {
+		parseCommitRenames(&renames, stdout)
+		close(done)
+	}()
+
+	stderr := new(bytes.Buffer)
+	err := NewCommand(ctx, "show", "--name-status", "--pretty=format:", "-z", "--diff-filter=R").AddDynamicArguments(commitID).Run(&RunOpts{
+		Dir:    repoPath,
+		Stdout: w,
+		Stderr: stderr,
+	})
+	w.Close() // Close writer to exit parsing goroutine
+	if err != nil {
+		return nil, ConcatenateError(err, stderr.String())
+	}
+
+	<-done
+	return renames, nil
+}
+
 // GetFullCommitID returns full length (40) of commit ID by given short SHA in a repository.
 func GetFullCommitID(ctx context.Context, repoPath, shortID string) (string, error) {
 	commitID, _, err := NewCommand(ctx, "rev-parse").AddDynamicArguments(shortID).RunStdString(&RunOpts{Dir: repoPath})

modules/git/commit_test.go

@@ -278,3 +278,30 @@ func TestGetCommitFileStatusMerges(t *testing.T) {
 	assert.Equal(t, commitFileStatus.Removed, expected.Removed)
 	assert.Equal(t, commitFileStatus.Modified, expected.Modified)
 }
+
+func TestParseCommitRenames(t *testing.T) {
+	testcases := []struct {
+		output  string
+		renames [][2]string
+	}{
+		{
+			output:  "R090\x00renamed.txt\x00history.txt\x00",
+			renames: [][2]string{{"renamed.txt", "history.txt"}},
+		},
+		{
+			output:  "R090\x00renamed.txt\x00history.txt\x00R000\x00corruptedstdouthere",
+			renames: [][2]string{{"renamed.txt", "history.txt"}},
+		},
+		{
+			output:  "R100\x00renamed.txt\x00history.txt\x00R001\x00readme.md\x00README.md\x00",
+			renames: [][2]string{{"renamed.txt", "history.txt"}, {"readme.md", "README.md"}},
+		},
+	}
+
+	for _, testcase := range testcases {
+		renames := [][2]string{}
+		parseCommitRenames(&renames, strings.NewReader(testcase.output))
+
+		assert.Equal(t, testcase.renames, renames)
+	}
+}

options/locale/locale_en-US.ini

@@ -1280,6 +1280,8 @@ commits.find = Search
 commits.search_all = All Branches
 commits.author = Author
 commits.message = Message
+commits.browse_further = Browse further
+commits.renamed_from = Renamed from %s
 commits.date = Date
 commits.older = Older
 commits.newer = Newer

routers/web/repo/commit.go

@@ -239,6 +239,22 @@ func FileHistory(ctx *context.Context) {
 		ctx.ServerError("CommitsByFileAndRange", err)
 		return
 	}
+	oldestCommit := commits[len(commits)-1]
+
+	renamedFiles, err := git.GetCommitFileRenames(ctx, ctx.Repo.GitRepo.Path, oldestCommit.ID.String())
+	if err != nil {
+		ctx.ServerError("GetCommitFileRenames", err)
+		return
+	}
+
+	for _, renames := range renamedFiles {
+		if renames[1] == fileName {
+			ctx.Data["OldFilename"] = renames[0]
+			ctx.Data["OldFilenameHistory"] = fmt.Sprintf("%s/commits/commit/%s/%s", ctx.Repo.RepoLink, oldestCommit.ID.String(), renames[0])
+			break
+		}
+	}
+
 	ctx.Data["Commits"] = git_model.ConvertFromGitCommit(ctx, commits, ctx.Repo.Repository)
 
 	ctx.Data["Username"] = ctx.Repo.Owner.Name

templates/repo/commits.tmpl

@@ -13,6 +13,11 @@
 			</div>
 		</div>
 		{{template "repo/commits_table" .}}
+		{{if .OldFilename}}
+			<div class="ui bottom attached header">
+				<span>{{ctx.Locale.Tr "repo.commits.renamed_from" .OldFilename}} (<a href="{{.OldFilenameHistory}}">{{ctx.Locale.Tr "repo.commits.browse_further"}}</a>)</span>
+			</div>
+		{{end}}
 	</div>
 </div>
 {{template "base/footer" .}}

tests/gitea-repositories-meta/user2/repo59.git/objects/info/packs

@@ -0,0 +1,2 @@
+P pack-6dd3a6fe138f1d77e14c2e6b8e6c41e5ae242adf.pack
+

tests/gitea-repositories-meta/user2/repo59.git/packed-refs

@@ -1,3 +1,4 @@
 # pack-refs with: peeled fully-peeled sorted 
-d8f53dfb33f6ccf4169c34970b5e747511c18beb refs/heads/master
+d8f53dfb33f6ccf4169c34970b5e747511c18beb refs/heads/cake-recipe
+80b83c5c8220c3aa3906e081f202a2a7563ec879 refs/heads/master
 d8f53dfb33f6ccf4169c34970b5e747511c18beb refs/tags/v1.0

tests/gitea-repositories-meta/user2/repo59.git/refs/heads/cake-recipe

@@ -1 +0,0 @@
-d8f53dfb33f6ccf4169c34970b5e747511c18beb

tests/integration/repo_test.go

@@ -552,3 +552,33 @@ func TestGeneratedSourceLink(t *testing.T) {
 		assert.Equal(t, "/user27/repo49/src/commit/aacbdfe9e1c4b47f60abe81849045fa4e96f1d75/test/test.txt", dataURL)
 	})
 }
+
+func TestRenamedFileHistory(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	t.Run("Renamed file", func(t *testing.T) {
+		defer tests.PrintCurrentTest(t)()
+
+		req := NewRequest(t, "GET", "/user2/repo59/commits/branch/master/license")
+		resp := MakeRequest(t, req, http.StatusOK)
+
+		htmlDoc := NewHTMLParser(t, resp.Body)
+
+		renameNotice := htmlDoc.doc.Find(".ui.bottom.attached.header")
+		assert.Equal(t, 1, renameNotice.Length())
+		assert.Contains(t, renameNotice.Text(), "Renamed from licnse (Browse further)")
+
+		oldFileHistoryLink, ok := renameNotice.Find("a").Attr("href")
+		assert.True(t, ok)
+		assert.Equal(t, "/user2/repo59/commits/commit/80b83c5c8220c3aa3906e081f202a2a7563ec879/licnse", oldFileHistoryLink)
+	})
+
+	t.Run("Non renamed file", func(t *testing.T) {
+		req := NewRequest(t, "GET", "/user2/repo59/commits/branch/master/README.md")
+		resp := MakeRequest(t, req, http.StatusOK)
+
+		htmlDoc := NewHTMLParser(t, resp.Body)
+
+		htmlDoc.AssertElement(t, ".ui.bottom.attached.header", false)
+	})
+}