diff --git a/services/context/repo.go b/services/context/repo.go
index 2df2b7ea40..68c404e571 100644
--- a/services/context/repo.go
+++ b/services/context/repo.go
@@ -823,7 +823,7 @@ func getRefName(ctx *Base, repo *Repository, pathType RepoRefType) string {
 		// For legacy and API support only full commit sha
 		parts := strings.Split(path, "/")
 
-		if len(parts) > 0 && len(parts[0]) == git.ObjectFormatFromName(repo.Repository.ObjectFormatName).FullLength() {
+		if len(parts) > 1 && len(parts[0]) == git.ObjectFormatFromName(repo.Repository.ObjectFormatName).FullLength() {
 			repo.TreePath = strings.Join(parts[1:], "/")
 			return parts[0]
 		}