1 files changed, 23 insertions, 0 deletions
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 7457efef013..c72b6e9033d 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -31,6 +31,29 @@ describe MergeRequest do
     end
   end
 
+  describe 'locking' do
+    using RSpec::Parameterized::TableSyntax
+
+    where(:lock_version) do
+      [
+        [0],
+        ["0"]
+      ]
+    end
+
+    with_them do
+      it 'works when a merge request has a NULL lock_version' do
+        merge_request = create(:merge_request)
+
+        described_class.where(id: merge_request.id).update_all('lock_version = NULL')
+
+        merge_request.update!(lock_version: lock_version, title: 'locking test')
+
+        expect(merge_request.reload.title).to eq('locking test')
+      end
+    end
+  end
+
   describe '#squash_in_progress?' do
     let(:repo_path) do
       Gitlab::GitalyClient::StorageSettings.allow_disk_access do