Add basic test for code coverage stats

Add simplecov regex to code coverage field in project level CI/CD
general pipeline settings.

Add qa data selectors to the general pipelines section and to the
coverage regex field in the form so they can be validated, used
for selection, and modified.

Create new page object for general pipelines settings and initialize in
QA module. Verify required elements and add method for modifying
coverage regex.

Modify ci_cd page object to validate general pipelines element and
add method to expand the section.

app/views/projects/settings/ci_cd/_form.html.haml

@@ -103,7 +103,7 @@
           .input-group
             %span.input-group-prepend
               .input-group-text /
-            = f.text_field :build_coverage_regex, class: 'form-control', placeholder: 'Regular expression'
+            = f.text_field :build_coverage_regex, class: 'form-control', placeholder: 'Regular expression', data: { qa_selector: 'build_coverage_regex_field' }
             %span.input-group-append
               .input-group-text /
           %p.form-text.text-muted
@@ -143,7 +143,7 @@
                 go test -cover (Go)
                 %code coverage: \d+.\d+% of statements
 
-        = f.submit _('Save changes'), class: "btn btn-success"
+        = f.submit _('Save changes'), class: "btn btn-success", data: { qa_selector: 'save_general_pipelines_changes_button' }
 
 %hr
 

app/views/projects/settings/ci_cd/show.html.haml

@@ -5,7 +5,7 @@
 - expanded = expanded_by_default?
 - general_expanded = @project.errors.empty? ? expanded : true
 
-%section.settings#js-general-pipeline-settings.no-animate{ class: ('expanded' if general_expanded) }
+%section.settings#js-general-pipeline-settings.no-animate{ class: ('expanded' if general_expanded), data: { qa_selector: 'general_pipelines_settings_content' } }
   .settings-header
     %h4
       = _("General pipelines")

qa/qa.rb

@@ -252,6 +252,7 @@ module QA
         autoload :Main, 'qa/page/project/settings/main'
         autoload :Repository, 'qa/page/project/settings/repository'
         autoload :CICD, 'qa/page/project/settings/ci_cd'
+        autoload :GeneralPipelines, 'qa/page/project/settings/general_pipelines'
         autoload :AutoDevops, 'qa/page/project/settings/auto_devops'
         autoload :DeployKeys, 'qa/page/project/settings/deploy_keys'
         autoload :DeployTokens, 'qa/page/project/settings/deploy_tokens'

qa/qa/page/project/settings/ci_cd.rb

@@ -11,6 +11,13 @@ module QA
             element :autodevops_settings_content
             element :runners_settings_content
             element :variables_settings_content
+            element :general_pipelines_settings_content
+          end
+
+          def expand_general_pipelines(&block)
+            expand_section(:general_pipelines_settings_content) do
+              Settings::GeneralPipelines.perform(&block)
+            end
           end
 
           def expand_runners_settings(&block)

qa/qa/page/project/settings/general_pipelines.rb

+# frozen_string_literal: true
+
+module QA
+  module Page
+    module Project
+      module Settings
+        class GeneralPipelines < Page::Base
+          include Common
+
+          view 'app/views/projects/settings/ci_cd/_form.html.haml' do
+            element :build_coverage_regex_field
+            element :save_general_pipelines_changes_button
+          end
+
+          def configure_coverage_regex(pattern)
+            fill_element :build_coverage_regex_field, pattern
+            click_element :save_general_pipelines_changes_button
+          end
+        end
+      end
+    end
+  end
+end

qa/qa/specs/features/browser_ui/4_verify/testing/view_code_coverage_spec.rb

+# frozen_string_literal: true
+
+module QA
+  context 'Verify', :docker, :runner, quarantine: { type: :new } do
+    describe 'Code coverage statistics' do
+      let(:simplecov) { '\(\d+.\d+\%\) covered' }
+      let(:executor) { "qa-runner-#{Time.now.to_i}" }
+      let(:runner) do
+        Resource::Runner.fabricate_via_api! do |runner|
+          runner.name = executor
+        end
+      end
+
+      let(:merge_request) do
+        Resource::MergeRequest.fabricate_via_api! do |mr|
+          mr.project = runner.project
+          mr.file_name = '.gitlab-ci.yml'
+          mr.file_content = <<~EOF
+            test:
+              tags:
+                - qa
+                - e2e
+              script:
+                - echo '(66.67%) covered'
+          EOF
+        end
+      end
+
+      before do
+        Flow::Login.sign_in
+      end
+
+      after do
+        runner.remove_via_api!
+      end
+
+      it 'creates an MR with code coverage statistics' do
+        runner.project.visit!
+        configure_code_coverage(simplecov)
+        merge_request.visit!
+
+        Page::MergeRequest::Show.perform do |mr_widget|
+          Support::Retrier.retry_until(max_attempts: 5, sleep_interval: 5) do
+            mr_widget.has_pipeline_status?(/Pipeline #\d+ passed/)
+          end
+          expect(mr_widget).to have_content('Coverage 66.67%')
+        end
+      end
+    end
+
+    private
+
+    def configure_code_coverage(coverage_tool_pattern)
+      Page::Project::Menu.perform(&:go_to_ci_cd_settings)
+      Page::Project::Settings::CICD.perform do |settings|
+        settings.expand_general_pipelines do |coverage|
+          coverage.configure_coverage_regex(coverage_tool_pattern)
+        end
+      end
+    end
+  end
+end