repo/pull: detect case when no merge base found (#4434)

vendor/github.com/gogits/git-module/error.go

@@ -48,3 +48,14 @@ func IsErrUnsupportedVersion(err error) bool {
 func (err ErrUnsupportedVersion) Error() string {
 	return fmt.Sprintf("Operation requires higher version [required: %s]", err.Required)
 }
+
+type ErrNoMergeBase struct{}
+
+func IsErrNoMergeBase(err error) bool {
+	_, ok := err.(ErrNoMergeBase)
+	return ok
+}
+
+func (err ErrNoMergeBase) Error() string {
+	return "no merge based found"
+}

vendor/github.com/gogits/git-module/git.go

@@ -10,7 +10,7 @@ import (
 	"time"
 )
 
-const _VERSION = "0.6.1"
+const _VERSION = "0.6.2"
 
 func Version() string {
 	return _VERSION

vendor/github.com/gogits/git-module/repo_pull.go

@@ -22,7 +22,13 @@ type PullRequestInfo struct {
 // GetMergeBase checks and returns merge base of two branches.
 func (repo *Repository) GetMergeBase(base, head string) (string, error) {
 	stdout, err := NewCommand("merge-base", base, head).RunInDir(repo.Path)
-	return strings.TrimSpace(stdout), err
+	if err != nil {
+		if strings.HasSuffix(err.Error(), " 1") {
+			return "", ErrNoMergeBase{}
+		}
+		return "", err
+	}
+	return strings.TrimSpace(stdout), nil
 }
 
 // GetPullRequestInfo generates and returns pull request information
@@ -47,7 +53,7 @@ func (repo *Repository) GetPullRequestInfo(basePath, baseBranch, headBranch stri
 	prInfo := new(PullRequestInfo)
 	prInfo.MergeBase, err = repo.GetMergeBase(remoteBranch, headBranch)
 	if err != nil {
-		return nil, fmt.Errorf("GetMergeBase: %v", err)
+		return nil, err
 	}
 
 	logs, err := NewCommand("log", prInfo.MergeBase+"..."+headBranch, _PRETTY_LOG_FORMAT).RunInDirBytes(repo.Path)