Merge branch 'feature/test-coverage-badge' into 'master'

Add test coverage badge

## What does this MR do?

This MR adds a test coverage badge.

Test coverage badge will be a SVG image you can embed in README.md or on your website that will be created dynamically by GitLab, to show information about how much of the code is being covered by tests. In addition to coverage-regexp feature we currently have, this feature will make it possible to use the coverage data obtained from the build log. We will support both - pipeline coverage, or test coverage for particular job in the pipeline. 

![coverage_badges](/uploads/dfa307339eb58c8138e551b42c0d8756/coverage_badges.png)

![coverage_badge](/uploads/30406e4bdcf979b2900ffe8996728c97/coverage_badge.png)

## What are the relevant issue numbers?

Closes #3714

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] ~~API support added~~
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5708

2 files changed, 105 insertions, 14 deletions

diff --git a/spec/features/projects/badges/coverage_spec.rb b/spec/features/projects/badges/coverage_spec.rb
new file mode 100644
index 00000000000..af86d3c338a
--- /dev/null
+++ b/spec/features/projects/badges/coverage_spec.rb
@@ -0,0 +1,73 @@
+require 'spec_helper'
+
+feature 'test coverage badge' do
+  given!(:user) { create(:user) }
+  given!(:project) { create(:project, :private) }
+
+  given!(:pipeline) do
+    create(:ci_pipeline, project: project,
+                         ref: 'master',
+                         sha: project.commit.id)
+  end
+
+  context 'when user has access to view badge' do
+    background do
+      project.team << [user, :developer]
+      login_as(user)
+    end
+
+    scenario 'user requests coverage badge image for pipeline' do
+      create_job(coverage: 100, name: 'test:1')
+      create_job(coverage: 90, name: 'test:2')
+
+      show_test_coverage_badge
+
+      expect_coverage_badge('95%')
+    end
+
+    scenario 'user requests coverage badge for specific job' do
+      create_job(coverage: 50, name: 'test:1')
+      create_job(coverage: 50, name: 'test:2')
+      create_job(coverage: 85, name: 'coverage')
+
+      show_test_coverage_badge(job: 'coverage')
+
+      expect_coverage_badge('85%')
+    end
+
+    scenario 'user requests coverage badge for pipeline without coverage' do
+      create_job(coverage: nil, name: 'test')
+
+      show_test_coverage_badge
+
+      expect_coverage_badge('unknown')
+    end
+  end
+
+  context 'when user does not have access to view badge' do
+    background { login_as(user) }
+
+    scenario 'user requests test coverage badge image' do
+      show_test_coverage_badge
+
+      expect(page).to have_http_status(404)
+    end
+  end
+
+  def create_job(coverage:, name:)
+    create(:ci_build, name: name,
+                      coverage: coverage,
+                      pipeline: pipeline)
+  end
+
+  def show_test_coverage_badge(job: nil)
+    visit coverage_namespace_project_badges_path(
+      project.namespace, project, ref: :master, job: job, format: :svg)
+  end
+
+  def expect_coverage_badge(coverage)
+    svg = Nokogiri::XML.parse(page.body)
+    expect(page.response_headers['Content-Type']).to include('image/svg+xml')
+    expect(svg.at(%Q{text:contains("#{coverage}")})).to be_truthy
+  end
+end
diff --git a/spec/features/projects/badges/list_spec.rb b/spec/features/projects/badges/list_spec.rb
index 75166bca119..67a4a5d1ab1 100644
--- a/spec/features/projects/badges/list_spec.rb
+++ b/spec/features/projects/badges/list_spec.rb
@@ -9,25 +9,43 @@ feature 'list of badges' do
     visit namespace_project_pipelines_settings_path(project.namespace, project)
   end
 
-  scenario 'user displays list of badges' do
-    expect(page).to have_content 'build status'
-    expect(page).to have_content 'Markdown'
-    expect(page).to have_content 'HTML'
-    expect(page).to have_css('.highlight', count: 2)
-    expect(page).to have_xpath("//img[@alt='build status']")
-
-    page.within('.highlight', match: :first) do
-      expect(page).to have_content 'badges/master/build.svg'
+  scenario 'user wants to see build status badge' do
+    page.within('.build-status') do
+      expect(page).to have_content 'build status'
+      expect(page).to have_content 'Markdown'
+      expect(page).to have_content 'HTML'
+      expect(page).to have_css('.highlight', count: 2)
+      expect(page).to have_xpath("//img[@alt='build status']")
+
+      page.within('.highlight', match: :first) do
+        expect(page).to have_content 'badges/master/build.svg'
+      end
     end
   end
 
-  scenario 'user changes current ref on badges list page', js: true do
-    first('.js-project-refs-dropdown').click
+  scenario 'user wants to see coverage report badge' do
+    page.within('.coverage-report') do
+      expect(page).to have_content 'coverage report'
+      expect(page).to have_content 'Markdown'
+      expect(page).to have_content 'HTML'
+      expect(page).to have_css('.highlight', count: 2)
+      expect(page).to have_xpath("//img[@alt='coverage report']")
 
-    page.within '.project-refs-form' do
-      click_link 'improve/awesome'
+      page.within('.highlight', match: :first) do
+        expect(page).to have_content 'badges/master/coverage.svg'
+      end
     end
+  end
+
+  scenario 'user changes current ref of build status badge', js: true do
+    page.within('.build-status') do
+      first('.js-project-refs-dropdown').click
 
-    expect(page).to have_content 'badges/improve/awesome/build.svg'
+      page.within '.project-refs-form' do
+        click_link 'improve/awesome'
+      end
+
+      expect(page).to have_content 'badges/improve/awesome/build.svg'
+    end
   end
 end