Add checking what components use govuk-frontend

If a component being used in an application is uses govuk-frontend
ES6 JS, then a tag will be added to indicate this in the Component
Audit view.

app/models/govuk_publishing_components/audit_comparer.rb

@@ -279,6 +279,7 @@ def get_components_by_application
 
         results << {
           name: component_name,
+          govuk_frontend: component[:uses_govuk_frontend],
           count: locations.length,
           locations:,
         }

app/models/govuk_publishing_components/audit_components.rb

@@ -118,6 +118,11 @@ def get_component_asset_detail(detail, component)
         else
           @component_numbers[type.to_sym] += 1
           details["#{type}_exists".to_sym] = true
+
+          if type == "javascript" && uses_govuk_frontend?(file)
+            details[:uses_govuk_frontend] = true
+          end
+
           details["#{type}_lines".to_sym] = count_lines_in(file)
           details["#{type}_link".to_sym] = get_asset_link(type, component)
         end
@@ -130,6 +135,10 @@ def count_lines_in(file)
       File.read(file).each_line.count
     end
 
+    def uses_govuk_frontend?(file)
+      File.read(file).match(/require govuk\/components/)
+    end
+
     def clean_files(files, replace)
       files.map { |file| clean_file_name(file.gsub(replace, "")) }.sort
     end

app/views/govuk_publishing_components/audit/_items_in_applications.html.erb

@@ -6,6 +6,9 @@
           <div class="govuk-summary-list__row">
             <dt class="govuk-summary-list__key">
               <%= item[:name] %> (<%= pluralize(item[:count], 'use') %>)
+              <% if item[:govuk_frontend] %>
+                <span class="govuk-tag">ES6 JS</span>
+              <% end %>
             </dt>
             <dd class="govuk-summary-list__value">
               <% item[:locations].each do |application| %>