override favicon for development to find tabs more easily

app/helpers/page_layout_helper.rb

@@ -34,6 +34,10 @@ module PageLayoutHelper
     end
   end
 
+  def favicon
+    Rails.env.development? ? 'favicon-purple.ico' : 'favicon.ico'
+  end
+
   def page_image
     default = image_url('gitlab_logo.png')
 

app/views/layouts/_head.html.haml

@@ -23,7 +23,7 @@
   %title= page_title(site_name)
   %meta{ name: "description", content: page_description }
 
-  = favicon_link_tag 'favicon.ico'
+  = favicon_link_tag favicon
 
   = stylesheet_link_tag "application", media: "all"
   = stylesheet_link_tag "print",       media: "print"

spec/helpers/page_layout_helper_spec.rb

@@ -40,6 +40,18 @@ describe PageLayoutHelper do
     end
   end
 
+  describe 'favicon' do
+    it 'defaults to favicon.ico' do
+      allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new('production'))
+      expect(helper.favicon).to eq 'favicon.ico'
+    end
+
+    it 'has purple favicon for development' do
+      allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new('development'))
+      expect(helper.favicon).to eq 'favicon-purple.ico'
+    end
+  end
+
   describe 'page_image' do
     it 'defaults to the GitLab logo' do
       expect(helper.page_image).to end_with 'assets/gitlab_logo.png'