Add .diff and .patch support to compare

modules/git/tree.go

@@ -73,3 +73,14 @@ func (repo *Repository) GetTreePathLatestCommit(refName, treePath string) (*Comm
 	}
 	return repo.GetCommit(strings.TrimSpace(stdout))
 }
+
+// RevParse resolves a revision reference to other git-related objects
+func (repo *Repository) RevParse(ref, file string) (string, error) {
+	stdout, _, err := NewCommand("rev-parse").
+		AddDynamicArguments(ref+":"+file).
+		RunStdString(repo.Ctx, &RunOpts{Dir: repo.Path})
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(stdout), nil
+}

routers/common/compare.go

@@ -18,4 +18,5 @@ type CompareInfo struct {
 	BaseBranch       string
 	HeadBranch       string
 	DirectComparison bool
+	RawDiffType      git.RawDiffType
 }

routers/web/repo/compare.go

@@ -228,10 +228,31 @@ func ParseCompareInfo(ctx *context.Context) *common.CompareInfo {
 	)
 
 	infoPath = ctx.PathParam("*")
+
 	var infos []string
+
 	if infoPath == "" {
 		infos = []string{baseRepo.DefaultBranch, baseRepo.DefaultBranch}
 	} else {
+		// check if head is a branch or tag only if infoPath ends with .diff or .patch
+		if strings.HasSuffix(infoPath, ".diff") || strings.HasSuffix(infoPath, ".patch") {
+			infos = strings.SplitN(infoPath, "...", 2)
+			if len(infos) != 2 {
+				infos = strings.SplitN(infoPath, "..", 2) // match github behavior
+			}
+			ref2IsBranch := gitrepo.IsBranchExist(ctx, ctx.Repo.Repository, infos[1])
+			ref2IsTag := gitrepo.IsTagExist(ctx, ctx.Repo.Repository, infos[1])
+			if !ref2IsBranch && !ref2IsTag {
+				if strings.HasSuffix(infoPath, ".diff") {
+					ci.RawDiffType = git.RawDiffNormal
+					infoPath = strings.TrimSuffix(infoPath, ".diff")
+				} else if strings.HasSuffix(infoPath, ".patch") {
+					ci.RawDiffType = git.RawDiffPatch
+					infoPath = strings.TrimSuffix(infoPath, ".patch")
+				}
+			}
+		}
+
 		infos = strings.SplitN(infoPath, "...", 2)
 		if len(infos) != 2 {
 			if infos = strings.SplitN(infoPath, "..", 2); len(infos) == 2 {
@@ -729,6 +750,7 @@ func CompareDiff(ctx *context.Context) {
 		return
 	}
 
+	ctx.Data["PageIsCompareDiff"] = true
 	ctx.Data["PullRequestWorkInProgressPrefixes"] = setting.Repository.PullRequest.WorkInProgressPrefixes
 	ctx.Data["DirectComparison"] = ci.DirectComparison
 	ctx.Data["OtherCompareSeparator"] = ".."
@@ -743,6 +765,16 @@ func CompareDiff(ctx *context.Context) {
 		return
 	}
 
+	if ci.RawDiffType != "" {
+		err := git.GetRepoRawDiffForFile(ci.HeadGitRepo, ci.BaseBranch, ci.HeadBranch, ci.RawDiffType, "", ctx.Resp)
+		if err != nil {
+			ctx.ServerError("GetRepoRawDiffForFile", err)
+			return
+		}
+		ctx.Resp.Flush()
+		return
+	}
+
 	baseTags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
 	if err != nil {
 		ctx.ServerError("GetTagNamesByRepoID", err)

templates/repo/diff/options_dropdown.tmpl

@@ -10,6 +10,9 @@
 		{{else if .Commit.ID.String}}
 			<a class="item" href="{{$.RepoLink}}/commit/{{PathEscape .Commit.ID.String}}.patch" download="{{ShortSha .Commit.ID.String}}.patch">{{ctx.Locale.Tr "repo.diff.download_patch"}}</a>
 			<a class="item" href="{{$.RepoLink}}/commit/{{PathEscape .Commit.ID.String}}.diff" download="{{ShortSha .Commit.ID.String}}.diff">{{ctx.Locale.Tr "repo.diff.download_diff"}}</a>
+		{{else if $.PageIsCompareDiff}}
+			<a class="item" href="{{$.Link}}.patch" download="{{$.BaseBranch}}...{{$.HeadBranch}}.patch">{{ctx.Locale.Tr "repo.diff.download_patch"}}</a>
+			<a class="item" href="{{$.Link}}.diff" download="{{$.BaseBranch}}...{{$.HeadBranch}}.diff">{{ctx.Locale.Tr "repo.diff.download_diff"}}</a>
 		{{end}}
 		<a id="expand-files-btn" class="item">{{ctx.Locale.Tr "repo.pulls.expand_files"}}</a>
 		<a id="collapse-files-btn" class="item">{{ctx.Locale.Tr "repo.pulls.collapse_files"}}</a>

tests/integration/compare_test.go

@@ -9,10 +9,12 @@ import (
 	"net/url"
 	"strings"
 	"testing"
+	"time"
 
 	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/models/unittest"
 	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/test"
 	repo_service "code.gitea.io/gitea/services/repository"
 	"code.gitea.io/gitea/tests"
@@ -158,3 +160,99 @@ func TestCompareCodeExpand(t *testing.T) {
 		}
 	})
 }
+
+func TestCompareRawDiffNormal(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, u *url.URL) {
+		user1 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
+		repo, err := repo_service.CreateRepositoryDirectly(db.DefaultContext, user1, user1, repo_service.CreateRepoOptions{
+			Name:          "test_raw_diff",
+			Readme:        "Default",
+			AutoInit:      true,
+			DefaultBranch: "main",
+		}, true)
+		assert.NoError(t, err)
+		session := loginUser(t, user1.Name)
+
+		r, _ := gitrepo.OpenRepository(db.DefaultContext, repo)
+
+		oldRef, _ := r.GetBranchCommit(repo.DefaultBranch)
+		oldBlobRef, _ := r.RevParse(oldRef.ID.String(), "README.md")
+
+		testEditFile(t, session, user1.Name, repo.Name, "main", "README.md", strings.Repeat("a\n", 2))
+
+		newRef, _ := r.GetBranchCommit(repo.DefaultBranch)
+		newBlobRef, _ := r.RevParse(newRef.ID.String(), "README.md")
+
+		req := NewRequest(t, "GET", fmt.Sprintf("/user1/test_raw_diff/compare/%s...%s.diff", oldRef.ID.String(), newRef.ID.String()))
+		resp := session.MakeRequest(t, req, http.StatusOK)
+
+		expected := fmt.Sprintf(`diff --git a/README.md b/README.md
+index %s..%s 100644
+--- a/README.md
++++ b/README.md
+@@ -1,2 +1,2 @@
+-# test_raw_diff
+-
++a
++a
+`, oldBlobRef[:7], newBlobRef[:7])
+		assert.Equal(t, expected, resp.Body.String())
+	})
+}
+
+func TestCompareRawDiffPatch(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, u *url.URL) {
+		user1 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
+		repo, err := repo_service.CreateRepositoryDirectly(db.DefaultContext, user1, user1, repo_service.CreateRepoOptions{
+			Name:          "test_raw_diff",
+			Readme:        "Default",
+			AutoInit:      true,
+			DefaultBranch: "main",
+		}, true)
+		assert.NoError(t, err)
+		session := loginUser(t, user1.Name)
+
+		r, _ := gitrepo.OpenRepository(db.DefaultContext, repo)
+
+		// Get the old commit and blob reference
+		oldRef, _ := r.GetBranchCommit(repo.DefaultBranch)
+		oldBlobRef, _ := r.RevParse(oldRef.ID.String(), "README.md")
+
+		resp := testEditFile(t, session, user1.Name, repo.Name, "main", "README.md", strings.Repeat("a\n", 2))
+
+		newRef, _ := r.GetBranchCommit(repo.DefaultBranch)
+		newBlobRef, _ := r.RevParse(newRef.ID.String(), "README.md")
+
+		// Get the last modified time from the response header
+		respTs, _ := time.Parse(time.RFC1123, resp.Result().Header.Get("Last-Modified"))
+		respTs = respTs.In(time.Local)
+
+		// Format the timestamp to match the expected format in the patch
+		customFormat := "Mon, 02 Jan 2006 15:04:05 -0700"
+		respTsStr := respTs.Format(customFormat)
+
+		req := NewRequest(t, "GET", fmt.Sprintf("/user1/test_raw_diff/compare/%s...%s.patch", oldRef.ID.String(), newRef.ID.String()))
+		resp = session.MakeRequest(t, req, http.StatusOK)
+
+		expected := fmt.Sprintf(`From %s Mon Sep 17 00:00:00 2001
+From: User One <[email protected]>
+Date: %s
+Subject: [PATCH] Update README.md
+
+---
+ README.md | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/README.md b/README.md
+index %s..%s 100644
+--- a/README.md
++++ b/README.md
+@@ -1,2 +1,2 @@
+-# test_raw_diff
+-
++a
++a
+`, newRef.ID.String(), respTsStr, oldBlobRef[:7], newBlobRef[:7])
+		assert.Equal(t, expected, resp.Body.String())
+	})
+}