1 files changed, 28 insertions, 0 deletions
diff --git a/spec/lib/gitlab/background_migration/cleanup_concurrent_schema_change_spec.rb b/spec/lib/gitlab/background_migration/cleanup_concurrent_schema_change_spec.rb
new file mode 100644
index 00000000000..2931b5e6dd3
--- /dev/null
+++ b/spec/lib/gitlab/background_migration/cleanup_concurrent_schema_change_spec.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+require 'spec_helper'
+
+RSpec.describe Gitlab::BackgroundMigration::CleanupConcurrentSchemaChange do
+  describe '#perform' do
+    it 'new column does not exist' do
+      expect(subject).to receive(:column_exists?).with(:issues, :closed_at_timestamp).and_return(false)
+      expect(subject).not_to receive(:column_exists?).with(:issues, :closed_at)
+      expect(subject).not_to receive(:define_model_for)
+
+      expect(subject.perform(:issues, :closed_at, :closed_at_timestamp)).to be_nil
+    end
+
+    it 'old column does not exist' do
+      expect(subject).to receive(:column_exists?).with(:issues, :closed_at_timestamp).and_return(true)
+      expect(subject).to receive(:column_exists?).with(:issues, :closed_at).and_return(false)
+      expect(subject).not_to receive(:define_model_for)
+
+      expect(subject.perform(:issues, :closed_at, :closed_at_timestamp)).to be_nil
+    end
+
+    it 'has both old and new columns' do
+      expect(subject).to receive(:column_exists?).twice.and_return(true)
+
+      expect { subject.perform('issues', :closed_at, :created_at) }.to raise_error(NotImplementedError)
+    end
+  end
+end