Merge branch 'code-blocks-vue-pre' into 'master'

Adds v-pre to code blocks in comments

## What does this MR do?

Allows users to comment on discussions with code that contains `{{`

Previously because of the discussion part being a Vue app it was being converted by Vue & therefore creating JS errors & the code not displaying correctly. This adds `v-pre` onto the code element to allow the user to write code that would contain `{{`

## What are the relevant issue numbers?

Closes #22911

See merge request !6674

CHANGELOG

@@ -15,6 +15,7 @@ v 8.13.0 (unreleased)
   - Simplify Mentionable concern instance methods
   - Fix permission for setting an issue's due date
   - Expose expires_at field when sharing project on API
+  - Fix VueJS template tags being rendered in code comments
   - Fix issue with page scrolling to top when closing or pinning sidebar (lukehowell)
   - Allow the Koding integration to be configured through the API
   - Added soft wrap button to repository file/blob editor

lib/banzai/filter/sanitization_filter.rb

@@ -25,7 +25,7 @@ module Banzai
         return if customized?(whitelist[:transformers])
 
         # Allow code highlighting
-        whitelist[:attributes]['pre'] = %w(class)
+        whitelist[:attributes]['pre'] = %w(class v-pre)
         whitelist[:attributes]['span'] = %w(class)
 
         # Allow table alignment

lib/banzai/filter/syntax_highlight_filter.rb

@@ -30,7 +30,7 @@ module Banzai
           # users can still access an issue/comment/etc.
         end
 
-        highlighted = %(<pre class="#{css_classes}"><code>#{code}</code></pre>)
+        highlighted = %(<pre class="#{css_classes}" v-pre="true"><code>#{code}</code></pre>)
 
         # Extracted to a method to measure it
         replace_parent_pre_element(node, highlighted)

spec/features/notes_on_merge_requests_spec.rb

@@ -240,6 +240,18 @@ describe 'Comments', feature: true do
           is_expected.to have_css('.notes_holder .note', count: 1)
           is_expected.to have_button('Reply...')
         end
+
+        it 'adds code to discussion' do
+          click_button 'Reply...'
+
+          page.within(first('.js-discussion-note-form')) do
+            fill_in 'note[note]', with: '```{{ test }}```'
+
+            click_button('Comment')
+          end
+
+          expect(page).to have_content('{{ test }}')
+        end
       end
     end
   end

spec/lib/banzai/filter/syntax_highlight_filter_spec.rb

@@ -6,21 +6,21 @@ describe Banzai::Filter::SyntaxHighlightFilter, lib: true do
   context "when no language is specified" do
     it "highlights as plaintext" do
       result = filter('<pre><code>def fun end</code></pre>')
-      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight plaintext"><code>def fun end</code></pre>')
+      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight plaintext" v-pre="true"><code>def fun end</code></pre>')
     end
   end
 
   context "when a valid language is specified" do
     it "highlights as that language" do
       result = filter('<pre><code class="ruby">def fun end</code></pre>')
-      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight ruby"><code><span class="k">def</span> <span class="nf">fun</span> <span class="k">end</span></code></pre>')
+      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight ruby" v-pre="true"><code><span class="k">def</span> <span class="nf">fun</span> <span class="k">end</span></code></pre>')
     end
   end
 
   context "when an invalid language is specified" do
     it "highlights as plaintext" do
       result = filter('<pre><code class="gnuplot">This is a test</code></pre>')
-      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight plaintext"><code>This is a test</code></pre>')
+      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight plaintext" v-pre="true"><code>This is a test</code></pre>')
     end
   end
 
@@ -31,7 +31,7 @@ describe Banzai::Filter::SyntaxHighlightFilter, lib: true do
 
     it "highlights as plaintext" do
       result = filter('<pre><code class="ruby">This is a test</code></pre>')
-      expect(result.to_html).to eq('<pre class="code highlight"><code>This is a test</code></pre>')
+      expect(result.to_html).to eq('<pre class="code highlight" v-pre="true"><code>This is a test</code></pre>')
     end
   end
 end