From 09f7d84f4cbbfdf81caec922638d8fec4cb7dfca Mon Sep 17 00:00:00 2001
From: zeripath <art27@cantab.net>
Date: Mon, 8 Jun 2020 19:07:41 +0100
Subject: Ensure rejected push to refs/pull/index/head fails nicely (#11724)

A pre-receive hook that rejects pushes to refs/pull/index/head
will cause a broken PR which causes an internal server error
whenever it is viewed. This PR handles prevents the internal server
error by handling non-existent pr heads and sends a flash error
informing the creator there was a problem.

Signed-off-by: Andrew Thornton <art27@cantab.net>
---
 routers/repo/pull.go | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

(limited to 'routers/repo/pull.go')

diff --git a/routers/repo/pull.go b/routers/repo/pull.go
index 30913e4766..42846fb93d 100644
--- a/routers/repo/pull.go
+++ b/routers/repo/pull.go
@@ -430,6 +430,20 @@ func PrepareViewPullInfo(ctx *context.Context, issue *models.Issue) *git.Compare
 
 	sha, err := baseGitRepo.GetRefCommitID(pull.GetGitRefName())
 	if err != nil {
+		if git.IsErrNotExist(err) {
+			ctx.Data["IsPullRequestBroken"] = true
+			if pull.IsSameRepo() {
+				ctx.Data["HeadTarget"] = pull.HeadBranch
+			} else if pull.HeadRepo == nil {
+				ctx.Data["HeadTarget"] = "<deleted>:" + pull.HeadBranch
+			} else {
+				ctx.Data["HeadTarget"] = pull.HeadRepo.OwnerName + ":" + pull.HeadBranch
+			}
+			ctx.Data["BaseTarget"] = pull.BaseBranch
+			ctx.Data["NumCommits"] = 0
+			ctx.Data["NumFiles"] = 0
+			return nil
+		}
 		ctx.ServerError(fmt.Sprintf("GetRefCommitID(%s)", pull.GetGitRefName()), err)
 		return nil
 	}
@@ -464,12 +478,10 @@ func PrepareViewPullInfo(ctx *context.Context, issue *models.Issue) *git.Compare
 		ctx.Data["IsPullRequestBroken"] = true
 		if pull.IsSameRepo() {
 			ctx.Data["HeadTarget"] = pull.HeadBranch
+		} else if pull.HeadRepo == nil {
+			ctx.Data["HeadTarget"] = "<deleted>:" + pull.HeadBranch
 		} else {
-			if pull.HeadRepo == nil {
-				ctx.Data["HeadTarget"] = "<deleted>:" + pull.HeadBranch
-			} else {
-				ctx.Data["HeadTarget"] = pull.HeadRepo.OwnerName + ":" + pull.HeadBranch
-			}
+			ctx.Data["HeadTarget"] = pull.HeadRepo.OwnerName + ":" + pull.HeadBranch
 		}
 	}
 
@@ -952,6 +964,16 @@ func CompareAndPullRequestPost(ctx *context.Context, form auth.CreateIssueForm)
 		if models.IsErrUserDoesNotHaveAccessToRepo(err) {
 			ctx.Error(400, "UserDoesNotHaveAccessToRepo", err.Error())
 			return
+		} else if git.IsErrPushRejected(err) {
+			pushrejErr := err.(*git.ErrPushRejected)
+			message := pushrejErr.Message
+			if len(message) == 0 {
+				ctx.Flash.Error(ctx.Tr("repo.pulls.push_rejected_no_message"))
+			} else {
+				ctx.Flash.Error(ctx.Tr("repo.pulls.push_rejected", utils.SanitizeFlashErrorString(pushrejErr.Message)))
+			}
+			ctx.Redirect(ctx.Repo.RepoLink + "/pulls/" + com.ToStr(pullIssue.Index))
+			return
 		}
 		ctx.ServerError("NewPullRequest", err)
 		return
-- 
cgit v1.2.3