Improve spec for pipeline metrics worker

app/workers/pipeline_metrics_worker.rb

@@ -5,11 +5,26 @@ class PipelineMetricsWorker
 
   def perform(pipeline_id)
     Ci::Pipeline.find_by(id: pipeline_id).try do |pipeline|
-      merge_requests = pipeline.merge_requests.map(&:id)
-
-      metrics = MergeRequest::Metrics.where(merge_request_id: merge_requests)
-      metrics.update_all(latest_build_started_at: pipeline.started_at) if pipeline.active?
-      metrics.update_all(latest_build_finished_at: pipeline.finished_at) if pipeline.success?
+      update_metrics_for_active_pipeline(pipeline) if pipeline.active?
+      update_metrics_for_succeeded_pipeline(pipeline) if pipeline.success?
     end
   end
+
+  private
+
+  def update_metrics_for_active_pipeline(pipeline)
+    metrics(pipeline).update_all(latest_build_started_at: pipeline.started_at, latest_build_finished_at: nil)
+  end
+
+  def update_metrics_for_succeeded_pipeline(pipeline)
+    metrics(pipeline).update_all(latest_build_started_at: pipeline.started_at, latest_build_finished_at: pipeline.finished_at)
+  end
+
+  def metrics(pipeline)
+    MergeRequest::Metrics.where(merge_request_id: merge_requests(pipeline))
+  end
+
+  def merge_requests(pipeline)
+    pipeline.merge_requests.map(&:id)
+  end
 end

spec/models/ci/pipeline_spec.rb

@@ -187,33 +187,24 @@ describe Ci::Pipeline, models: true do
       end
     end
 
-    describe "merge request metrics" do
+    describe 'merge request metrics' do
       let(:project) { FactoryGirl.create :project }
       let(:pipeline) { FactoryGirl.create(:ci_empty_pipeline, status: 'created', project: project, ref: 'master', sha: project.repository.commit('master').id) }
       let!(:merge_request) { create(:merge_request, source_project: project, source_branch: pipeline.ref) }
 
+      before do
+        expect(PipelineMetricsWorker).to receive(:perform_async).with(pipeline.id)
+      end
+
       context 'when transitioning to running' do
-        it 'records the build start time' do
-          time = Time.now
-          Timecop.freeze(time) { build.run }
-
-          expect(merge_request.reload.metrics.latest_build_started_at).to be_within(1.second).of(time)
-        end
-
-        it 'clears the build end time' do
-          build.run
-
-          expect(merge_request.reload.metrics.latest_build_finished_at).to be_nil
+        it 'schedules metrics workers' do
+          pipeline.run
         end
       end
 
       context 'when transitioning to success' do
-        it 'records the build end time' do
-          build.run
-          time = Time.now
-          Timecop.freeze(time) { build.success }
-
-          expect(merge_request.reload.metrics.latest_build_finished_at).to be_within(1.second).of(time)
+        it 'schedules metrics workers' do
+          pipeline.succeed
         end
       end
     end

spec/workers/pipeline_metrics_worker_spec.rb

@@ -0,0 +1,46 @@
+require 'spec_helper'
+
+describe PipelineMetricsWorker do
+  let(:project) { create(:project) }
+  let!(:merge_request) { create(:merge_request, source_project: project, source_branch: pipeline.ref) }
+
+  let(:pipeline) do
+    create(:ci_empty_pipeline,
+           status: status,
+           project: project,
+           ref: 'master',
+           sha: project.repository.commit('master').id,
+           started_at: 1.hour.ago,
+           finished_at: Time.now)
+  end
+
+  describe '#perform' do
+    subject { described_class.new.perform(pipeline.id) }
+
+    context 'when pipeline is running' do
+      let(:status) { 'running' }
+
+      it 'records the build start time' do
+        subject
+
+        expect(merge_request.reload.metrics.latest_build_started_at).to eq(pipeline.started_at)
+      end
+
+      it 'clears the build end time' do
+        subject
+
+        expect(merge_request.reload.metrics.latest_build_finished_at).to be_nil
+      end
+    end
+
+    context 'when pipeline succeeded' do
+      let(:status) { 'success' }
+
+      it 'records the build end time' do
+        subject
+
+        expect(merge_request.reload.metrics.latest_build_finished_at).to eq(pipeline.finished_at)
+      end
+    end
+  end
+end