Add feature flag async_add_build_failure_todo

Rollout: https://gitlab.com/gitlab-org/gitlab/-/issues/326726

app/models/commit_status.rb

@@ -179,6 +179,18 @@ class CommitStatus < ApplicationRecord
         ExpireJobCacheWorker.perform_async(id)
       end
     end
+
+    after_transition any => :failed do |commit_status|
+      next if Feature.enabled?(:async_add_build_failure_todo, commit_status.project, default_enabled: :yaml)
+      next unless commit_status.project
+
+      # rubocop: disable CodeReuse/ServiceClass
+      commit_status.run_after_commit do
+        MergeRequests::AddTodoWhenBuildFailsService
+          .new(project, nil).execute(self)
+      end
+      # rubocop: enable CodeReuse/ServiceClass
+    end
   end
 
   def self.names

app/workers/build_finished_worker.rb

@@ -36,7 +36,10 @@ class BuildFinishedWorker # rubocop:disable Scalability/IdempotentWorker
     BuildHooksWorker.perform_async(build.id)
     ExpirePipelineCacheWorker.perform_async(build.pipeline_id)
     ChatNotificationWorker.perform_async(build.id) if build.pipeline.chat?
-    ::Ci::MergeRequests::AddTodoWhenBuildFailsWorker.perform_async(build.id) if build.failed?
+
+    if build.failed? && Feature.enabled?(:async_add_build_failure_todo, build.project, default_enabled: :yaml)
+      ::Ci::MergeRequests::AddTodoWhenBuildFailsWorker.perform_async(build.id)
+    end
 
     ##
     # We want to delay sending a build trace to object storage operation to

config/feature_flags/development/async_add_build_failure_todo.yml

+---
+name: async_add_build_failure_todo
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/57490/diffs
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/326726
+milestone: '13.11'
+type: development
+group: group::continuous integration
+default_enabled: false

spec/models/ci/build_spec.rb

@@ -3670,15 +3670,42 @@ RSpec.describe Ci::Build do
         subject.drop!
       end
 
-      it 'creates a todo', :sidekiq_inline do
-        project.add_developer(user)
+      context 'when async_add_build_failure_todo flag enabled' do
+        it 'creates a todo async', :sidekiq_inline do
+          project.add_developer(user)
+
+          expect_next_instance_of(TodoService) do |todo_service|
+            expect(todo_service)
+              .to receive(:merge_request_build_failed).with(merge_request)
+          end
 
-        expect_next_instance_of(TodoService) do |todo_service|
-          expect(todo_service)
-            .to receive(:merge_request_build_failed).with(merge_request)
+          subject.drop!
         end
 
-        subject.drop!
+        it 'does not create a sync todo' do
+          project.add_developer(user)
+
+          expect(TodoService).not_to receive(:new)
+
+          subject.drop!
+        end
+      end
+
+      context 'when async_add_build_failure_todo flag disabled' do
+        before do
+          stub_feature_flags(async_add_build_failure_todo: false)
+        end
+
+        it 'creates a todo sync' do
+          project.add_developer(user)
+
+          expect_next_instance_of(TodoService) do |todo_service|
+            expect(todo_service)
+              .to receive(:merge_request_build_failed).with(merge_request)
+          end
+
+          subject.drop!
+        end
       end
     end
 

spec/workers/build_finished_worker_spec.rb

@@ -39,6 +39,18 @@ RSpec.describe BuildFinishedWorker do
 
           subject
         end
+
+        context 'when async_add_build_failure_todo disabled' do
+          before do
+            stub_feature_flags(async_add_build_failure_todo: false)
+          end
+
+          it 'does not add a todo' do
+            expect(::Ci::MergeRequests::AddTodoWhenBuildFailsWorker).not_to receive(:perform_async)
+
+            subject
+          end
+        end
       end
 
       context 'when build has a chat' do