Modifies commit branches section

- Display the default branch (if the limit is not exceeded)
- Requires '...' to be clicked before showing the rest of the branches and/or tags
- Fixes haml lints

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

@@ -61,7 +61,7 @@
     %span.cgray= n_('parent', 'parents', @commit.parents.count)
     - @commit.parents.each do |parent|
       = link_to parent.short_id, project_commit_path(@project, parent), class: "commit-sha"
-    %div.commit-info.branches
+    .commit-info.branches
       %i.fa.fa-spinner.fa-spin
   - if @commit.last_pipeline

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

-.has-tooltip{class: "limit-box limit-box-#{objects.singularize}", data: { title: "Project has too many #{objects} to search"} }
+.has-tooltip{ class: "limit-box limit-box-#{objects.singularize}", data: { title: "Project has too many #{objects} to search"} }
   .limit-icon
     - if objects == "branches"
       = icon('code-fork')
     - else
       = icon('tag')
   .limit-message
-    %span= "#{objects.capitalize} unavailable"
+    %span #{objects.capitalize} unavailable

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

 - if @branches_limit_exceeded
   = render 'limit_exceeded_message', objects: 'branches'
-- elsif @branches.any?
-  = commit_branches_links(@project, @branches)
-- if @tags_limit_exceeded
-  = render 'limit_exceeded_message', objects: 'tags'
-- elsif @tags.any?
-  = commit_tags_links(@project, @tags)
+- else
+  - branch = commit_default_branch(@project, @branches)
+  = commit_branch_link(project_ref_path(@project, branch), branch)
+- if @branches.any? || @tags.any? || @tags_limit_exceeded
+  %span
+    = link_to "…", "#", class: "js-details-expand label label-gray"
+    %span.js-details-content.hide
+      = commit_branches_links(@project, @branches)
+      - if @tags_limit_exceeded
+        = render 'limit_exceeded_message', objects: 'tags'
+      - else
+        = commit_tags_links(@project, @tags)

spec/views/projects/commit/branches.html.haml_spec.rb

@@ -7,7 +7,7 @@ describe 'projects/commit/branches.html.haml' do
     assign(:project, project)
   end
-  context 'branches and tags' do
+  context 'when branches and tags are available' do
     before do
       assign(:branches, ['master', 'test-branch'])
       assign(:branches_limit_exceeded, false)
@@ -17,16 +17,75 @@ describe 'projects/commit/branches.html.haml' do
       render
     end
+    it 'shows default branch' do
+      expect(rendered).to have_link('master')
+    end
+
+    it 'shows js expand link' do
+      expect(rendered).to have_selector('.js-details-expand')
+    end
+
     it 'shows branch and tag links' do
+      expect(rendered).to have_link('test-branch')
+      expect(rendered).to have_link('tag1')
+    end
+  end
+
+  context 'when branches are available but no tags' do
+    before do
+      assign(:branches, ['master', 'test-branch'])
+      assign(:branches_limit_exceeded, false)
+      assign(:tags, [])
+      assign(:tags_limit_exceeded, true)
+
+      render
+    end
+
+    it 'shows branches' do
       expect(rendered).to have_link('master')
       expect(rendered).to have_link('test-branch')
+    end
+
+    it 'shows js expand link' do
+      expect(rendered).to have_selector('.js-details-expand')
+    end
+
+    it 'shows limit exceeded message for tags' do
+      expect(rendered).to have_text('Tags unavailable')
+    end
+  end
+
+  context 'when tags are available but no branches (just default)' do
+    before do
+      assign(:branches, ['master'])
+      assign(:branches_limit_exceeded, true)
+      assign(:tags, ['tag1', 'tag2'])
+      assign(:tags_limit_exceeded, false)
+
+      render
+    end
+
+    it 'shows default branch' do
+      expect(rendered).to have_text('master')
+    end
+
+    it 'shows js expand link' do
+      expect(rendered).to have_selector('.js-details-expand')
+    end
+
+    it 'shows tags' do
       expect(rendered).to have_link('tag1')
+      expect(rendered).to have_link('tag2')
+    end
+
+    it 'shows limit exceeded for branches' do
+      expect(rendered).to have_text('Branches unavailable')
     end
   end
-  context 'throttled branches and tags' do
+  context 'when branches and tags are not available' do
     before do
-      assign(:branches, [])
+      assign(:branches, ['master'])
       assign(:branches_limit_exceeded, true)
       assign(:tags, [])
       assign(:tags_limit_exceeded, true)
@@ -34,6 +93,14 @@ describe 'projects/commit/branches.html.haml' do
       render
     end
+    it 'shows default branch' do
+      expect(rendered).to have_text('master')
+    end
+
+    it 'shows js expand link' do
+      expect(rendered).to have_selector('.js-details-expand')
+    end
+
     it 'shows too many to search' do
       expect(rendered).to have_text('Branches unavailable')
       expect(rendered).to have_text('Tags unavailable')