Do not display ci build status if builds enabled but no `.gitlab-ci.yml`

Ref #3827

app/models/ci/commit.rb

@@ -220,6 +220,16 @@ module Ci
       update!(committed_at: DateTime.now)
     end
 
+    ##
+    # This method checks if build status should be displayed.
+    #
+    # Build status should be available only if builds are enabled
+    # on project level and `.gitlab-ci.yml` file is present.
+    #
+    def show_build_status?
+      gl_project.builds_enabled? && ci_yaml_file
+    end
+
     private
 
     def save_yaml_error(error)

app/views/projects/commit/_commit_box.html.haml

@@ -40,7 +40,7 @@
   - @commit.parents.each do |parent|
     = link_to parent.short_id, namespace_project_commit_path(@project.namespace, @project, parent), class: "monospace"
 
-- if @ci_commit
+- if @ci_commit && @ci_commit.show_build_status?
   .pull-right
     = link_to ci_status_path(@ci_commit), class: "ci-status ci-#{@ci_commit.status}" do
       = ci_status_icon(@ci_commit)

app/views/projects/commits/_commit.html.haml

@@ -9,7 +9,7 @@
 - cache_key.push(ci_commit.status) if ci_commit
 
 = cache(cache_key) do
-  %li.commit.js-toggle-container
+  %li.commit.js-toggle-container{ id: "commit-#{commit.short_id}" }
     .commit-row-title
       %strong.str-truncated
         = link_to_gfm commit.title, namespace_project_commit_path(project.namespace, project, commit.id), class: "commit-row-message"
@@ -17,7 +17,7 @@
           %a.text-expander.js-toggle-button ...
 
       .pull-right
-        - if ci_commit
+        - if ci_commit && ci_commit.show_build_status?
           = render_ci_status(ci_commit)
            
         = clipboard_button(clipboard_text: commit.id)

spec/features/commits_spec.rb

@@ -19,7 +19,36 @@ describe 'Commits' do
 
     let!(:build) { FactoryGirl.create :ci_build, commit: commit }
 
-    describe 'GET /:project/commits/:sha/ci' do
+    describe 'Project commits' do
+      context 'builds enabled' do
+        context '.gitlab-ci.yml found' do
+          before do
+            visit namespace_project_commits_path(project.namespace, project, :master)
+          end
+
+          it 'should show build status' do
+            page.within("//li[@id='commit-#{commit.short_sha}']") do
+              expect(page).to have_css(".ci-status-link")
+            end
+          end
+        end
+
+        context 'no .gitlab-ci.yml found' do
+          before do
+            stub_ci_commit_yaml_file(nil)
+            visit namespace_project_commits_path(project.namespace, project, :master)
+          end
+
+          it 'should not show build status' do
+            page.within("//li[@id='commit-#{commit.short_sha}']") do
+              expect(page).to have_no_css(".ci-status-link")
+            end
+          end
+        end
+      end
+    end
+
+    describe 'Commit builds' do
       before do
         visit ci_status_path(commit)
       end