Serve .patch for pull requests (#3305)

* Serve .patch for pull requests

Closes #3259
Updates "git" module, for GetFormatPatch

* Handle io.Copy error

2 files changed, 48 insertions, 1 deletions

diff --git a/routers/repo/pull.go b/routers/repo/pull.go
index 9de8268957..515b6a91f8 100644
--- a/routers/repo/pull.go
+++ b/routers/repo/pull.go
@@ -9,6 +9,7 @@ package repo
 import (
 	"container/list"
 	"fmt"
+	"io"
 	"path"
 	"strings"
 
@@ -1033,7 +1034,7 @@ func DownloadPullDiff(ctx *context.Context) {
 		return
 	}
 
-	// Redirect elsewhere if it's not a pull request
+	// Return not found if it's not a pull request
 	if !issue.IsPull {
 		ctx.Handle(404, "DownloadPullDiff",
 			fmt.Errorf("Issue is not a pull request"))
@@ -1054,3 +1055,48 @@ func DownloadPullDiff(ctx *context.Context) {
 
 	ctx.ServeFileContent(patch)
 }
+
+// DownloadPullPatch render a pull's raw patch
+func DownloadPullPatch(ctx *context.Context) {
+	issue, err := models.GetIssueByIndex(ctx.Repo.Repository.ID, ctx.ParamsInt64(":index"))
+	if err != nil {
+		if models.IsErrIssueNotExist(err) {
+			ctx.Handle(404, "GetIssueByIndex", err)
+		} else {
+			ctx.Handle(500, "GetIssueByIndex", err)
+		}
+		return
+	}
+
+	// Return not found if it's not a pull request
+	if !issue.IsPull {
+		ctx.Handle(404, "DownloadPullDiff",
+			fmt.Errorf("Issue is not a pull request"))
+		return
+	}
+
+	pr := issue.PullRequest
+
+	if err = pr.GetHeadRepo(); err != nil {
+		ctx.Handle(500, "GetHeadRepo", err)
+		return
+	}
+
+	headGitRepo, err := git.OpenRepository(pr.HeadRepo.RepoPath())
+	if err != nil {
+		ctx.Handle(500, "OpenRepository", err)
+		return
+	}
+
+	patch, err := headGitRepo.GetFormatPatch(pr.MergeBase, pr.HeadBranch)
+	if err != nil {
+		ctx.Handle(500, "GetFormatPatch", err)
+		return
+	}
+
+	_, err = io.Copy(ctx, patch)
+	if err != nil {
+		ctx.Handle(500, "io.Copy", err)
+		return
+	}
+}
diff --git a/routers/routes/routes.go b/routers/routes/routes.go
index 3e00f55ebf..fc7401fc9a 100644
--- a/routers/routes/routes.go
+++ b/routers/routes/routes.go
@@ -625,6 +625,7 @@ func RegisterRoutes(m *macaron.Macaron) {
 
 		m.Group("/pulls/:index", func() {
 			m.Get(".diff", repo.DownloadPullDiff)
+			m.Get(".patch", repo.DownloadPullPatch)
 			m.Get("/commits", context.RepoRef(), repo.ViewPullCommits)
 			m.Get("/files", context.RepoRef(), repo.SetEditorconfigIfExists, repo.SetDiffViewStyle, repo.ViewPullFiles)
 			m.Post("/merge", reqRepoWriter, bindIgnErr(auth.MergePullRequestForm{}), repo.MergePullRequest)