Enable pipeline activity limit and add EE specs

app/services/ci/create_pipeline_service.rb

@@ -6,7 +6,8 @@ module Ci
                 Gitlab::Ci::Pipeline::Chain::Validate::Repository,
                 Gitlab::Ci::Pipeline::Chain::Validate::Config,
                 Gitlab::Ci::Pipeline::Chain::Skip,
-                Gitlab::Ci::Pipeline::Chain::Create].freeze
+                Gitlab::Ci::Pipeline::Chain::Create,
+                EE::Gitlab::Ci::Pipeline::Chain::Limit::Activity].freeze
 
     def execute(source, ignore_skip_ci: false, save_on_errors: true, trigger_request: nil, schedule: nil, mirror_update: false, &block)
       @pipeline = Ci::Pipeline.new(

spec/ee/spec/services/ci/create_pipeline_service_spec.rb

+require 'spec_helper'
+
+describe Ci::CreatePipelineService, '#execute' do
+  set(:namespace) { create(:namespace, plan: EE::Namespace::GOLD_PLAN) }
+  set(:project) { create(:project, :repository, namespace: namespace) }
+  set(:user) { create(:user) }
+
+  let(:service) do
+    params = { ref: 'master',
+               before: '00000000',
+               after: project.commit.id,
+               commits: [{ message: 'some commit' }] }
+
+    described_class.new(project, user, params)
+  end
+
+  before do
+    project.add_developer(user)
+    stub_ci_pipeline_to_return_yaml_file
+  end
+
+  describe 'CI/CD Quotas / Limits' do
+    context 'when there are not limits enabled' do
+      it 'enqueues a new pipeline' do
+        pipeline = create_pipeline!
+
+        expect(pipeline).to be_persisted
+        expect(pipeline).to be_pending
+      end
+    end
+
+    context 'when pipeline activity limit is exceeded' do
+      before do
+        namespace.plan.update_column(:active_pipelines_limit, 2)
+
+        create(:ci_pipeline, project: project, status: 'pending')
+        create(:ci_pipeline, project: project, status: 'running')
+      end
+
+      it 'drops the pipeline and cancels all jobs' do
+        pipeline = create_pipeline!
+
+        # TODO, check failure reason
+        expect(pipeline).to be_persisted
+        expect(pipeline).to be_failed
+        expect(pipeline.statuses).to all(be_canceled)
+      end
+    end
+
+    context 'when pipeline size limit is exceeded' do
+    end
+  end
+
+  def create_pipeline!
+    service.execute(:push)
+  end
+end