Use `force: true` for fetch_source_branchfix-rugged-fetch-source-branch

2 files changed, 16 insertions, 1 deletions

diff --git a/lib/gitlab/git/repository.rb b/lib/gitlab/git/repository.rb
index 848a782446a..ec4b4a4c993 100644
--- a/lib/gitlab/git/repository.rb
+++ b/lib/gitlab/git/repository.rb
@@ -1376,7 +1376,7 @@ module Gitlab
       def rugged_fetch_source_branch(source_repository, source_branch, local_ref)
         with_repo_branch_commit(source_repository, source_branch) do |commit|
           if commit
-            write_ref(local_ref, commit.sha)
+            write_ref(local_ref, commit.sha, force: true)
             true
           else
             false
diff --git a/spec/lib/gitlab/git/repository_spec.rb b/spec/lib/gitlab/git/repository_spec.rb
index 03a9cc488ca..65144dc7f24 100644
--- a/spec/lib/gitlab/git/repository_spec.rb
+++ b/spec/lib/gitlab/git/repository_spec.rb
@@ -1643,6 +1643,21 @@ describe Gitlab::Git::Repository, seed_helper: true do
             expect(repository.commit(local_ref).sha).to eq(expected_oid)
           end
         end
+
+        context 'when the ref exists locally' do
+          let(:source_branch) { 'master' }
+          let(:expected_oid) { SeedRepo::LastCommit::ID }
+
+          it 'writes the ref' do
+            # Sanity check: the commit should already exist
+            expect(repository.commit(expected_oid)).not_to be_nil
+
+            # Make sure the ref exists
+            expect(repository.fetch_source_branch!(source_repository, source_branch, local_ref)).to eq(true)
+            # Writing it once more should succeed
+            expect(repository.fetch_source_branch!(source_repository, source_branch, local_ref)).to eq(true)
+          end
+        end
       end
 
       context 'when the branch does not exist' do