Add spec for CSP subfolder

spec/lib/content_security_policy_spec.rb

@@ -99,6 +99,35 @@ describe ContentSecurityPolicy do
         http://test.localhost/extra-locales/
       ])
     end
+
+    it 'adds subfolder to CDN assets' do
+      set_cdn_url('https://cdn.com')
+      set_subfolder('/forum')
+
+      script_srcs = parse(policy)['script-src']
+      expect(script_srcs).to include(*%w[
+        https://cdn.com/forum/assets/
+        https://cdn.com/forum/brotli_asset/
+        https://cdn.com/forum/highlight-js/
+        https://cdn.com/forum/javascripts/
+        https://cdn.com/forum/plugins/
+        https://cdn.com/forum/theme-javascripts/
+        http://test.localhost/forum/extra-locales/
+      ])
+
+      global_setting(:s3_cdn_url, 'https://s3-cdn.com')
+
+      script_srcs = parse(policy)['script-src']
+      expect(script_srcs).to include(*%w[
+        https://s3-cdn.com/assets/
+        https://s3-cdn.com/brotli_asset/
+        https://cdn.com/forum/highlight-js/
+        https://cdn.com/forum/javascripts/
+        https://cdn.com/forum/plugins/
+        https://cdn.com/forum/theme-javascripts/
+        http://test.localhost/forum/extra-locales/
+      ])
+    end
   end
 
   it 'can be extended by plugins' do