From a7c0da02e8d8515e47880e12d6bbc73bbdb966f8 Mon Sep 17 00:00:00 2001
From: Alan Crosswell <alan@columbia.edu>
Date: Sun, 17 Jan 2021 18:16:19 -0500
Subject: [PATCH] pass in the specified git branch ref when cloning a single
 branch

---
 packages/backend-common/src/scm/git.ts                         | 3 ++-
 .../scaffolder-backend/src/scaffolder/stages/prepare/gitlab.ts | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/backend-common/src/scm/git.ts b/packages/backend-common/src/scm/git.ts
index b0a1df6541..55a8746d6e 100644
--- a/packages/backend-common/src/scm/git.ts
+++ b/packages/backend-common/src/scm/git.ts
@@ -86,13 +86,14 @@ export class Git {
     return git.commit({ fs, dir, message, author, committer });
   }
 
-  async clone({ url, dir }: { url: string; dir: string }): Promise<void> {
+  async clone({ url, dir, ref }: { url: string; dir: string; ref?: string }): Promise<void> {
     this.config.logger?.info(`Cloning repo {dir=${dir},url=${url}}`);
     return git.clone({
       fs,
       http,
       url,
       dir,
+      ref,
       singleBranch: true,
       depth: 1,
       onProgress: this.onProgressHandler(),
diff --git a/plugins/scaffolder-backend/src/scaffolder/stages/prepare/gitlab.ts b/plugins/scaffolder-backend/src/scaffolder/stages/prepare/gitlab.ts
index 1fca2ff0f9..7824687155 100644
--- a/plugins/scaffolder-backend/src/scaffolder/stages/prepare/gitlab.ts
+++ b/plugins/scaffolder-backend/src/scaffolder/stages/prepare/gitlab.ts
@@ -42,6 +42,7 @@ export class GitlabPreparer implements PreparerBase {
 
     const parsedGitLocation = parseGitUrl(location);
     const repositoryCheckoutUrl = parsedGitLocation.toString('https');
+    const ref = parsedGitLocation.toString('ref');
     const tempDir = await fs.promises.mkdtemp(
       path.join(workingDirectory, templateId),
     );
@@ -61,6 +62,7 @@ export class GitlabPreparer implements PreparerBase {
 
     await git.clone({
       url: repositoryCheckoutUrl,
+      ref: ref,
       dir: tempDir,
     });