Add a feature tests to check if a view can be rendered properly

spec/features/merge_requests/pipelines_spec.rb

+require 'spec_helper'
+
+feature 'Pipelines for Merge Requests', feature: true, js: true do
+  include WaitForAjax
+
+  given(:user) { create(:user) }
+  given(:merge_request) { create(:merge_request) }
+  given(:project) { merge_request.target_project }
+
+  before do
+    project.team << [user, :master]
+    login_as user
+  end
+
+  context 'with pipelines' do
+    let!(:pipeline) do
+      create(:ci_empty_pipeline,
+             project: merge_request.source_project,
+             ref: merge_request.source_branch,
+             sha: merge_request.diff_head_sha)
+    end
+
+    before do
+      visit namespace_project_merge_request_path(project.namespace, project, merge_request)
+    end
+
+    scenario 'does click a pipeline tab and sees a list of pipelines' do
+      page.within('.merge-request-tabs') do
+        click_link('Pipelines')
+      end
+      wait_for_ajax
+
+      expect(page).to have_selector('.pipeline-actions')
+    end
+  end
+
+  context 'without pipelines' do
+    before do
+      visit namespace_project_merge_request_path(project.namespace, project, merge_request)
+    end
+
+    scenario 'does not find a pipeline link' do
+      page.within('.merge-request-tabs') do
+        expect(page).not_to have_link('Pipelines')
+      end
+    end
+  end
+end