Improve checkBranchName (#17901)

The current implementation of checkBranchName is highly inefficient
involving opening the repository, the listing all of the branch names
checking them individually before then using using opened repo to get
the tags.

This PR avoids this by simply walking the references from show-ref
instead of opening the repository (in the nogogit case).

Signed-off-by: Andrew Thornton <art27@cantab.net>

1 files changed, 8 insertions, 3 deletions

diff --git a/modules/git/repo_branch.go b/modules/git/repo_branch.go
index 98b1bc8ae7..01933d7ade 100644
--- a/modules/git/repo_branch.go
+++ b/modules/git/repo_branch.go
@@ -95,7 +95,12 @@ func GetBranchesByPath(path string, skip, limit int) ([]*Branch, int, error) {
 	}
 	defer gitRepo.Close()
 
-	brs, countAll, err := gitRepo.GetBranches(skip, limit)
+	return gitRepo.GetBranches(skip, limit)
+}
+
+// GetBranches returns a slice of *git.Branch
+func (repo *Repository) GetBranches(skip, limit int) ([]*Branch, int, error) {
+	brs, countAll, err := repo.GetBranchNames(skip, limit)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -103,9 +108,9 @@ func GetBranchesByPath(path string, skip, limit int) ([]*Branch, int, error) {
 	branches := make([]*Branch, len(brs))
 	for i := range brs {
 		branches[i] = &Branch{
-			Path:    path,
+			Path:    repo.Path,
 			Name:    brs[i],
-			gitRepo: gitRepo,
+			gitRepo: repo,
 		}
 	}