1 files changed, 67 insertions, 0 deletions
diff --git a/spec/rubocop/cop/migration/prevent_single_statement_with_disable_ddl_transaction_spec.rb b/spec/rubocop/cop/migration/prevent_single_statement_with_disable_ddl_transaction_spec.rb
new file mode 100644
index 00000000000..968de7d2160
--- /dev/null
+++ b/spec/rubocop/cop/migration/prevent_single_statement_with_disable_ddl_transaction_spec.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+require 'rubocop_spec_helper'
+require_relative '../../../../rubocop/cop/migration/prevent_single_statement_with_disable_ddl_transaction'
+
+RSpec.describe RuboCop::Cop::Migration::PreventSingleStatementWithDisableDdlTransaction, feature_category: :database do
+  context 'when in migration' do
+    before do
+      allow(cop).to receive(:in_migration?).and_return(true)
+    end
+
+    it 'registers an offense when `disable_ddl_transaction!` is only for the :validate_foreign_key statement' do
+      code = <<~RUBY
+      class SomeMigration < Gitlab::Database::Migration[2.1]
+        disable_ddl_transaction!
+        def up
+          validate_foreign_key :emails, :user_id
+        end
+        def down
+          # no-op
+        end
+      end
+      RUBY
+
+      expect_offense(<<~RUBY, node: code, msg: described_class::MSG)
+        class SomeMigration < Gitlab::Database::Migration[2.1]
+          disable_ddl_transaction!
+          ^^^^^^^^^^^^^^^^^^^^^^^^ %{msg}
+          def up
+            validate_foreign_key :emails, :user_id
+          end
+          def down
+            # no-op
+          end
+        end
+      RUBY
+    end
+
+    it 'registers no offense when `disable_ddl_transaction!` is used with more than one statement' do
+      expect_no_offenses(<<~RUBY)
+        class SomeMigration < Gitlab::Database::Migration[2.1]
+          disable_ddl_transaction!
+          def up
+            add_concurrent_foreign_key :emails, :users, column: :user_id, on_delete: :cascade, validate: false
+            validate_foreign_key :emails, :user_id
+          end
+          def down
+            remove_foreign_key_if_exists :emails, column: :user_id
+          end
+        end
+      RUBY
+    end
+  end
+
+  context 'when outside of migration' do
+    it 'registers no offense' do
+      expect_no_offenses(<<~RUBY)
+        class SomeMigration
+          disable_ddl_transaction!
+          def up
+            validate_foreign_key :deployments, :environment_id
+          end
+        end
+      RUBY
+    end
+  end
+end