Fix pull view when head repository or head branch missed and close related pull requests when delete head repository or head branch (#9927)

* fix pull view when head repository or head branch missed and close related pull requests when delete branch

* fix pull view broken when head repository deleted

* close pull requests when head repositories deleted

* Add tests for broken pull request head repository or branch

* fix typo

* ignore special error when close pull request

Co-authored-by: Lauris BH <lauris@nix.lv>

services/pull/pull.go

@@ -355,3 +355,79 @@ func PushToBaseRepo(pr *models.PullRequest) (err error) {
 
 	return nil
 }
+
+type errlist []error
+
+func (errs errlist) Error() string {
+	if len(errs) > 0 {
+		var buf strings.Builder
+		for i, err := range errs {
+			if i > 0 {
+				buf.WriteString(", ")
+			}
+			buf.WriteString(err.Error())
+		}
+		return buf.String()
+	}
+	return ""
+}
+
+// CloseBranchPulls close all the pull requests who's head branch is the branch
+func CloseBranchPulls(doer *models.User, repoID int64, branch string) error {
+	prs, err := models.GetUnmergedPullRequestsByHeadInfo(repoID, branch)
+	if err != nil {
+		return err
+	}
+
+	prs2, err := models.GetUnmergedPullRequestsByBaseInfo(repoID, branch)
+	if err != nil {
+		return err
+	}
+
+	prs = append(prs, prs2...)
+	if err := models.PullRequestList(prs).LoadAttributes(); err != nil {
+		return err
+	}
+
+	var errs errlist
+	for _, pr := range prs {
+		if err = issue_service.ChangeStatus(pr.Issue, doer, true); err != nil && !models.IsErrIssueWasClosed(err) {
+			errs = append(errs, err)
+		}
+	}
+	if len(errs) > 0 {
+		return errs
+	}
+	return nil
+}
+
+// CloseRepoBranchesPulls close all pull requests which head branches are in the given repository
+func CloseRepoBranchesPulls(doer *models.User, repo *models.Repository) error {
+	branches, err := git.GetBranchesByPath(repo.RepoPath())
+	if err != nil {
+		return err
+	}
+
+	var errs errlist
+	for _, branch := range branches {
+		prs, err := models.GetUnmergedPullRequestsByHeadInfo(repo.ID, branch.Name)
+		if err != nil {
+			return err
+		}
+
+		if err = models.PullRequestList(prs).LoadAttributes(); err != nil {
+			return err
+		}
+
+		for _, pr := range prs {
+			if err = issue_service.ChangeStatus(pr.Issue, doer, true); err != nil && !models.IsErrIssueWasClosed(err) {
+				errs = append(errs, err)
+			}
+		}
+	}
+
+	if len(errs) > 0 {
+		return errs
+	}
+	return nil
+}