Add .diff and .patch support to compare

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

@@ -221,13 +221,9 @@
 	// base<-head: master...head:feature
 	// same repo: master...feature
 
-	var (
-		isSameRepo bool
-		infoPath   string
-		err        error
-	)
+	var isSameRepo bool
 
-	infoPath = ctx.PathParam("*")
+	infoPath := ctx.PathParam("*")
 	var infos []string
 	if infoPath == "" {
 		infos = []string{baseRepo.DefaultBranch, baseRepo.DefaultBranch}
@@ -247,12 +243,14 @@
 	ci.BaseBranch = infos[0]
 	ctx.Data["BaseBranch"] = ci.BaseBranch
 
-	// If there is no head repository, it means compare between same repository.
+	var err error
+
+	// If there is no head repository, it means compare between the same repository.
 	headInfos := strings.Split(infos[1], ":")
 	if len(headInfos) == 1 {
 		isSameRepo = true
 		ci.HeadUser = ctx.Repo.Owner
-		ci.HeadBranch = headInfos[0]
+		ci.HeadBranch, ci.RawDiffType = parseRefForRawDiff(ctx, ctx.Repo.Repository, headInfos[0])
 	} else if len(headInfos) == 2 {
 		headInfosSplit := strings.Split(headInfos[0], "/")
 		if len(headInfosSplit) == 1 {
@@ -265,20 +263,21 @@
 				}
 				return nil
 			}
-			ci.HeadBranch = headInfos[1]
+			// FIXME: how to correctly choose the head repository? The logic below (3-8) is quite complex, the real head repo is determined there
+			ci.HeadBranch, ci.RawDiffType = parseRefForRawDiff(ctx, ..., headInfos[1])
 			isSameRepo = ci.HeadUser.ID == ctx.Repo.Owner.ID
 			if isSameRepo {
 				ci.HeadRepo = baseRepo
 			}
 		} else {
 			ci.HeadRepo, err = repo_model.GetRepositoryByOwnerAndName(ctx, headInfosSplit[0], headInfosSplit[1])
 			if err != nil {
 				if repo_model.IsErrRepoNotExist(err) {
 					ctx.NotFound(nil)
 				} else {
 					ctx.ServerError("GetRepositoryByOwnerAndName", err)
 				}
 				return nil
 			}
 			if err := ci.HeadRepo.LoadOwner(ctx); err != nil {
 				if user_model.IsErrUserNotExist(err) {
@@ -288,7 +287,7 @@
 				}
 				return nil
 			}
-			ci.HeadBranch = headInfos[1]
+			ci.HeadBranch, ci.RawDiffType = parseRefForRawDiff(ctx, ci.HeadRepo, headInfos[1])
 			ci.HeadUser = ci.HeadRepo.Owner
 			isSameRepo = ci.HeadRepo.ID == ctx.Repo.Repository.ID
 		}
@@ -729,6 +728,7 @@
 		return
 	}
 
+	ctx.Data["PageIsCompareDiff"] = true
 	ctx.Data["PullRequestWorkInProgressPrefixes"] = setting.Repository.PullRequest.WorkInProgressPrefixes
 	ctx.Data["DirectComparison"] = ci.DirectComparison
 	ctx.Data["OtherCompareSeparator"] = ".."
@@ -743,6 +743,15 @@
 		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
+		}
+		return
+	}
+
 	baseTags, err := repo_model.GetTagNamesByRepoID(ctx, ctx.Repo.Repository.ID)
 	if err != nil {
 		ctx.ServerError("GetTagNamesByRepoID", err)
@@ -984,3 +993,20 @@
 	}
 	return diffLines, nil
 }
+
+func parseRefForRawDiff(ctx *context.Context, refRepo *repo_model.Repository, refShortName string) (string, git.RawDiffType) {
+	if !strings.HasSuffix(refShortName, ".diff") && !strings.HasSuffix(refShortName, ".patch") {
+		return refShortName, ""
+	}
+
+	if gitrepo.IsBranchExist(ctx, refRepo, refShortName) || gitrepo.IsTagExist(ctx, refRepo, refShortName) {
+		return refShortName, ""
+	}
+
+	if s, ok := strings.CutSuffix(refShortName, ".diff"); ok {
+		return s, git.RawDiffNormal
+	} else if s, ok = strings.CutSuffix(refShortName, ".patch"); ok {
+		return s, git.RawDiffPatch
+	}
+	return refShortName, ""
+}

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 +9,13 @@ 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"
+	git_module "code.gitea.io/gitea/modules/git"
+	"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 +161,212 @@ 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, _ := revParse(r, 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, _ := revParse(r, 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, _ := revParse(r, 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, _ := revParse(r, 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 <user1@example.com>
+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())
+	})
+}
+
+func TestCompareRawDiffNormalSameOwnerDifferentRepo(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)
+
+		headRepo, err := repo_service.CreateRepositoryDirectly(db.DefaultContext, user1, user1, repo_service.CreateRepoOptions{
+			Name:          "test_raw_diff_head",
+			Readme:        "Default",
+			AutoInit:      true,
+			DefaultBranch: "main",
+		}, true)
+		assert.NoError(t, err)
+
+		r, _ := gitrepo.OpenRepository(db.DefaultContext, repo)
+		hr, _ := gitrepo.OpenRepository(db.DefaultContext, headRepo)
+
+		oldRef, _ := r.GetBranchCommit(repo.DefaultBranch)
+		oldBlobRef, _ := revParse(r, oldRef.ID.String(), "README.md")
+
+		testEditFile(t, session, user1.Name, headRepo.Name, "main", "README.md", strings.Repeat("a\n", 2))
+
+		newRef, _ := hr.GetBranchCommit(headRepo.DefaultBranch)
+		newBlobRef, _ := revParse(hr, newRef.ID.String(), "README.md")
+
+		req := NewRequest(t, "GET", fmt.Sprintf("/user1/test_raw_diff/compare/%s...%s/%s:%s.diff", oldRef.ID.String(), user1.LowerName, headRepo.LowerName, 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 TestCompareRawDiffNormalAcrossForks(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, u *url.URL) {
+		user1 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
+		user2 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+
+		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)
+
+		headRepo, err := repo_service.ForkRepository(db.DefaultContext, user2, user2, repo_service.ForkRepoOptions{
+			BaseRepo:     repo,
+			Name:         repo.Name,
+			Description:  repo.Description,
+			SingleBranch: "",
+		})
+		assert.NoError(t, err)
+
+		session := loginUser(t, user2.Name)
+
+		r, _ := gitrepo.OpenRepository(db.DefaultContext, repo)
+		hr, _ := gitrepo.OpenRepository(db.DefaultContext, headRepo)
+
+		oldRef, _ := r.GetBranchCommit(repo.DefaultBranch)
+		oldBlobRef, _ := revParse(r, oldRef.ID.String(), "README.md")
+
+		testEditFile(t, session, user2.Name, headRepo.Name, "main", "README.md", strings.Repeat("a\n", 2))
+
+		newRef, _ := hr.GetBranchCommit(headRepo.DefaultBranch)
+		newBlobRef, _ := revParse(hr, newRef.ID.String(), "README.md")
+
+		session = loginUser(t, user1.Name)
+
+		req := NewRequest(t, "GET", fmt.Sprintf("/user1/test_raw_diff/compare/%s...%s:%s.diff", oldRef.ID.String(), user2.LowerName, 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())
+	})
+}
+
+// helper function to use rev-parse
+// revParse resolves a revision reference to other git-related objects
+func revParse(repo *git_module.Repository, ref, file string) (string, error) {
+	stdout, _, err := git_module.NewCommand("rev-parse").
+		AddDynamicArguments(ref+":"+file).
+		RunStdString(repo.Ctx, &git_module.RunOpts{Dir: repo.Path})
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(stdout), nil
+}