Introduce data-qa-selector to supplant .qa-class

In order to break away from using CSS classes as
our primary method of element identification, we
need to provide the ability to search for data
attributes.

Make Test::Sanity::Selectors now work

Utilize regex to match on literal strings of the element name

Suggest the data-qa-selector pattern vs the qa-

Add data-qa-selector to login page to start

We need a page that is heavily used in order to be
confident that this functionality works. Let's start
with the Login page

Use appropriate HAML data tag practices

6 files changed, 20 insertions, 9 deletions

diff --git a/app/views/devise/sessions/_new_base.html.haml b/app/views/devise/sessions/_new_base.html.haml
index 7dacd0b1d72..2f10f08c839 100644
--- a/app/views/devise/sessions/_new_base.html.haml
+++ b/app/views/devise/sessions/_new_base.html.haml
@@ -1,10 +1,10 @@
 = form_for(resource, as: resource_name, url: session_path(resource_name), html: { class: 'new_user gl-show-field-errors', 'aria-live' => 'assertive'}) do |f|
   .form-group
     = f.label "Username or email", for: "user_login", class: 'label-bold'
-    = f.text_field :login, class: "form-control top qa-login-field", autofocus: "autofocus", autocapitalize: "off", autocorrect: "off", required: true, title: "This field is required."
+    = f.text_field :login, class: "form-control top", autofocus: "autofocus", autocapitalize: "off", autocorrect: "off", required: true, title: "This field is required.", data: { qa_selector: 'login_field' }
   .form-group
     = f.label :password, class: 'label-bold'
-    = f.password_field :password, class: "form-control bottom qa-password-field", required: true, title: "This field is required."
+    = f.password_field :password, class: "form-control bottom", required: true, title: "This field is required.", data: { qa_selector: 'password_field' }
   - if devise_mapping.rememberable?
     .remember-me
       %label{ for: "user_remember_me" }
@@ -17,4 +17,4 @@
       = recaptcha_tags
 
   .submit-container.move-submit-down
-    = f.submit "Sign in", class: "btn btn-success qa-sign-in-button"
+    = f.submit "Sign in", class: "btn btn-success", data: { qa_selector: 'sign_in_button' }
diff --git a/app/views/layouts/devise.html.haml b/app/views/layouts/devise.html.haml
index ff3410f6268..e9a4a068599 100644
--- a/app/views/layouts/devise.html.haml
+++ b/app/views/layouts/devise.html.haml
@@ -1,7 +1,7 @@
 !!! 5
 %html.devise-layout-html{ class: system_message_class }
   = render "layouts/head"
-  %body.ui-indigo.login-page.application.navless.qa-login-page{ data: { page: body_data_page } }
+  %body.ui-indigo.login-page.application.navless{ data: { page: body_data_page, qa_selector: 'login_page' } }
     = header_message
     .page-wrap
       = render "layouts/header/empty"
diff --git a/app/views/layouts/header/_default.html.haml b/app/views/layouts/header/_default.html.haml
index f9ee6f42e23..36ae24fc4bf 100644
--- a/app/views/layouts/header/_default.html.haml
+++ b/app/views/layouts/header/_default.html.haml
@@ -5,7 +5,7 @@
 - else
   - search_path_url = search_path
 
-%header.navbar.navbar-gitlab.qa-navbar.navbar-expand-sm.js-navbar
+%header.navbar.navbar-gitlab.navbar-expand-sm.js-navbar{ data: { qa_selector: 'navbar' } }
   %a.sr-only.gl-accessibility{ href: "#content-body", tabindex: "1" } Skip to content
   .container-fluid
     .header-content
diff --git a/qa/qa/page/element.rb b/qa/qa/page/element.rb
index 7a01320901d..f9aa9cc6377 100644
--- a/qa/qa/page/element.rb
+++ b/qa/qa/page/element.rb
@@ -28,7 +28,7 @@ module QA
       end
 
       def selector_css
-        ".#{selector}"
+        "[data-qa-selector='#{@name}'],.#{selector}"
       end
 
       def expression
@@ -40,7 +40,7 @@ module QA
       end
 
       def matches?(line)
-        !!(line =~ expression)
+        !!(line =~ /["']#{name}['"]|#{expression}/)
       end
     end
   end
diff --git a/qa/spec/page/element_spec.rb b/qa/spec/page/element_spec.rb
index f746fe06e40..87c9fbf74a3 100644
--- a/qa/spec/page/element_spec.rb
+++ b/qa/spec/page/element_spec.rb
@@ -11,7 +11,7 @@ describe QA::Page::Element do
   describe '#selector_css' do
     it 'transforms element name into QA-specific clickable css selector' do
       expect(described_class.new(:sign_in_button).selector_css)
-        .to eq '.qa-sign-in-button'
+        .to include('.qa-sign-in-button')
     end
   end
 
@@ -49,6 +49,10 @@ describe QA::Page::Element do
     it 'does not match if QA selector is not there' do
       expect(subject.matches?('some_name selector')).to be false
     end
+
+    it 'matches when element name is specified' do
+      expect(subject.matches?('data:{qa:{selector:"some_name"}}')).to be true
+    end
   end
 
   describe 'attributes' do
@@ -106,4 +110,11 @@ describe QA::Page::Element do
       end
     end
   end
+
+  describe 'data-qa selectors' do
+    subject { described_class.new(:my_element) }
+    it 'properly translates to a data-qa-selector' do
+      expect(subject.selector_css).to include("[data-qa-selector='my_element']")
+    end
+  end
 end
diff --git a/rubocop/cop/qa/element_with_pattern.rb b/rubocop/cop/qa/element_with_pattern.rb
index d14eeaaeaf3..f7debf13151 100644
--- a/rubocop/cop/qa/element_with_pattern.rb
+++ b/rubocop/cop/qa/element_with_pattern.rb
@@ -30,7 +30,7 @@ module RuboCop
           return if args.first.nil?
 
           args.first.each_node(:str) do |arg|
-            add_offense(arg, message: MESSAGE % "qa-#{element_name.value.to_s.tr('_', '-')}")
+            add_offense(arg, message: MESSAGE % "data-qa-selector=\"#{element_name.value}\"")
           end
         end