Reset column information after the schema is migrated in MigrationsHelpers.schema_migrate_up!

spec/lib/gitlab/background_migration/deserialize_merge_request_diffs_and_commits_spec.rb

@@ -15,10 +15,6 @@ describe Gitlab::BackgroundMigration::DeserializeMergeRequestDiffsAndCommits, :m
         .to receive(:commits_count=).and_return(nil)
     end
 
-    after do
-      [Project, MergeRequest, MergeRequestDiff].each(&:reset_column_information)
-    end
-
     def diffs_to_hashes(diffs)
       diffs.as_json(only: Gitlab::Git::Diff::SERIALIZE_KEYS).map(&:with_indifferent_access)
     end

spec/lib/gitlab/background_migration/populate_merge_request_metrics_with_events_data_spec.rb

@@ -7,10 +7,6 @@ describe Gitlab::BackgroundMigration::PopulateMergeRequestMetricsWithEventsData,
       .to receive(:commits_count=).and_return(nil)
   end
 
-  after do
-    [Project, MergeRequest, MergeRequestDiff].each(&:reset_column_information)
-  end
-
   describe '#perform' do
     let(:mr_with_event) { create(:merge_request) }
     let!(:merged_event) { create(:event, :merged, target: mr_with_event) }

spec/migrations/convert_custom_notification_settings_to_columns_spec.rb

@@ -21,7 +21,7 @@ describe ConvertCustomNotificationSettingsToColumns, :migration do
         events[event] = true
       end
 
-      user = build(:user).becomes(user_class).tap(&:save!)
+      user = user_class.create!(email: "user-#{SecureRandom.hex}@example.org", username: "user-#{SecureRandom.hex}", encrypted_password: '12345678')
       create_params = { user_id: user.id, level: params[:level], events: events }
       notification_setting = described_class::NotificationSetting.create(create_params)
 
@@ -37,7 +37,7 @@ describe ConvertCustomNotificationSettingsToColumns, :migration do
         events[event] = true
       end
 
-      user = build(:user).becomes(user_class).tap(&:save!)
+      user = user_class.create!(email: "user-#{SecureRandom.hex}@example.org", username: "user-#{SecureRandom.hex}", encrypted_password: '12345678')
       create_params = events.merge(user_id: user.id, level: params[:level])
       notification_setting = described_class::NotificationSetting.create(create_params)
 

spec/support/migrations_helpers.rb

@@ -15,18 +15,22 @@ module MigrationsHelpers
     ActiveRecord::Migrator.migrations(migrations_paths)
   end
 
-  def reset_column_in_migration_models
+  def clear_schema_cache!
     ActiveRecord::Base.connection_pool.connections.each do |conn|
       conn.schema_cache.clear!
     end
+  end
 
-    described_class.constants.sort.each do |name|
-      const = described_class.const_get(name)
+  def reset_column_in_all_models
+    clear_schema_cache!
 
-      if const.is_a?(Class) && const < ActiveRecord::Base
-        const.reset_column_information
-      end
-    end
+    # Reset column information for the most offending classes **after** we
+    # migrated the schema up, otherwise, column information could be outdated
+    ActiveRecord::Base.descendants.each { |klass| klass.reset_column_information }
+
+    # Without that, we get errors because of missing attributes, e.g.
+    # super: no superclass method `elasticsearch_indexing' for #<ApplicationSetting:0x00007f85628508d8>
+    ApplicationSetting.define_attribute_methods
   end
 
   def previous_migration
@@ -45,7 +49,7 @@ module MigrationsHelpers
                                      migration_schema_version)
     end
 
-    reset_column_in_migration_models
+    reset_column_in_all_models
   end
 
   def schema_migrate_up!
@@ -53,7 +57,7 @@ module MigrationsHelpers
       ActiveRecord::Migrator.migrate(migrations_paths)
     end
 
-    reset_column_in_migration_models
+    reset_column_in_all_models
   end
 
   def disable_migrations_output