show group runners on runners page

app/controllers/projects/settings/ci_cd_controller.rb

@@ -67,10 +67,14 @@ module Projects
 
       def define_runners_variables
         @project_runners = @project.runners.ordered
+
         @assignable_runners = current_user.ci_authorized_runners
           .assignable_for(project).ordered.page(params[:page]).per(20)
         @shared_runners = ::Ci::Runner.shared.active
+
         @shared_runners_count = @shared_runners.count(:all)
+
+        @group_runners = ::Ci::Runner.belonging_to_group(@project.id)
       end
 
       def define_secret_variables

app/views/projects/runners/_group_runners.html.haml

+%h3 Group Runners
+
+.bs-callout.bs-callout-warning
+  GitLab Group Runners can execute code for all the projects in this group.
+  They can be managed using the #{link_to 'Runners API', help_page_path('api/runners.md')}.
+
+- if !@project.group
+  This project does not belong to a group and can therefore not make use of group Runners.
+
+- elsif @group_runners.empty?
+  This group does not provide any group Runners yet.
+
+  = render partial: 'ci/runner/how_to_setup_runner',
+           locals: { registration_token: @project.group.runners_token, type: 'group' }
+
+- else
+  %h4.underlined-title Available group Runners : #{@group_runners.count}
+  %ul.bordered-list
+    = render partial: 'projects/runners/runner', collection: @group_runners, as: :runner

app/views/projects/runners/_index.html.haml

@@ -23,3 +23,7 @@
     = render 'projects/runners/specific_runners'
   .col-sm-6
     = render 'projects/runners/shared_runners'
+.row
+  .col-sm-6
+  .col-sm-6
+    = render 'projects/runners/group_runners'

app/views/projects/runners/_runner.html.haml

@@ -26,7 +26,7 @@
         - else
           - runner_project = @project.runner_projects.find_by(runner_id: runner)
           = link_to 'Disable for this project', project_runner_project_path(@project, runner_project), data: { confirm: "Are you sure?" }, method: :delete, class: 'btn btn-danger btn-sm'
-      - elsif runner.specific?
+      - elsif runner.project?
         = form_for [@project.namespace.becomes(Namespace), @project, @project.runner_projects.new] do |f|
           = f.hidden_field :runner_id, value: runner.id
           = f.submit 'Enable for this project', class: 'btn btn-sm'

spec/features/runners_spec.rb

@@ -181,4 +181,44 @@ feature 'Runners' do
       expect(page.find('.shared-runners-description')).to have_content('Disable shared Runners')
     end
   end
+
+  context 'group runners' do
+    background do
+      project.add_master(user)
+    end
+
+    context 'project without a group' do
+      given(:project) { create :project }
+
+      scenario 'group runners are not available' do
+        visit runners_path(project)
+
+        expect(page).to have_content 'This project does not belong to a group and can therefore not make use of group Runners.'
+      end
+    end
+
+    context 'project with a group but no group runner' do
+      given(:group) { create :group }
+      given(:project) { create :project, group: group }
+
+      scenario 'group runners are not available' do
+        visit runners_path(project)
+
+        expect(page).to have_content 'This group does not provide any group Runners yet.'
+      end
+    end
+
+    context 'project with a group and a group runner' do
+      given(:group) { create :group }
+      given(:project) { create :project, group: group }
+      given!(:ci_runner) { create :ci_runner, groups: [group], description: 'group-runner' }
+
+      scenario 'group runners are available' do
+        visit runners_path(project)
+
+        expect(page).to have_content 'Available group Runners : 1'
+        expect(page).to have_content 'group-runner'
+      end
+    end
+  end
 end