Merge branch 'copy-as-md' into 'master'

Copying a rendered issue/comment will paste into GFM textareas as actual GFM

See merge request !8597

5 files changed, 16 insertions, 6 deletions

diff --git a/lib/banzai/filter/abstract_reference_filter.rb b/lib/banzai/filter/abstract_reference_filter.rb
index 6d04f68c8f9..a3d495a5da0 100644
--- a/lib/banzai/filter/abstract_reference_filter.rb
+++ b/lib/banzai/filter/abstract_reference_filter.rb
@@ -153,7 +153,7 @@ module Banzai
             title = object_link_title(object)
             klass = reference_class(object_sym)
 
-            data = data_attributes_for(link_content || match, project, object)
+            data = data_attributes_for(link_content || match, project, object, link: !!link_content)
 
             if matches.names.include?("url") && matches[:url]
               url = matches[:url]
@@ -172,9 +172,10 @@ module Banzai
         end
       end
 
-      def data_attributes_for(text, project, object)
+      def data_attributes_for(text, project, object, link: false)
         data_attribute(
           original:     text,
+          link:         link,
           project:      project.id,
           object_sym => object.id
         )
diff --git a/lib/banzai/filter/issue_reference_filter.rb b/lib/banzai/filter/issue_reference_filter.rb
index 4d1bc687696..fd6b9704132 100644
--- a/lib/banzai/filter/issue_reference_filter.rb
+++ b/lib/banzai/filter/issue_reference_filter.rb
@@ -62,7 +62,7 @@ module Banzai
         end
       end
 
-      def data_attributes_for(text, project, object)
+      def data_attributes_for(text, project, object, link: false)
         if object.is_a?(ExternalIssue)
           data_attribute(
             project: project.id,
diff --git a/lib/banzai/filter/syntax_highlight_filter.rb b/lib/banzai/filter/syntax_highlight_filter.rb
index 026b81ac175..a447e2b8bff 100644
--- a/lib/banzai/filter/syntax_highlight_filter.rb
+++ b/lib/banzai/filter/syntax_highlight_filter.rb
@@ -20,17 +20,19 @@ module Banzai
         code = node.text
         css_classes = "code highlight"
         lexer = lexer_for(language)
+        lang = lexer.tag
 
         begin
           code = format(lex(lexer, code))
 
-          css_classes << " js-syntax-highlight #{lexer.tag}"
+          css_classes << " js-syntax-highlight #{lang}"
         rescue
+          lang = nil
           # Gracefully handle syntax highlighter bugs/errors to ensure
           # users can still access an issue/comment/etc.
         end
 
-        highlighted = %(<pre class="#{css_classes}" v-pre="true"><code>#{code}</code></pre>)
+        highlighted = %(<pre class="#{css_classes}" lang="#{lang}" v-pre="true"><code>#{code}</code></pre>)
 
         # Extracted to a method to measure it
         replace_parent_pre_element(node, highlighted)
diff --git a/lib/banzai/filter/video_link_filter.rb b/lib/banzai/filter/video_link_filter.rb
index ac7bbcb0d10..b64a1287d4d 100644
--- a/lib/banzai/filter/video_link_filter.rb
+++ b/lib/banzai/filter/video_link_filter.rb
@@ -35,7 +35,8 @@ module Banzai
           src: element['src'],
           width: '400',
           controls: true,
-          'data-setup' => '{}')
+          'data-setup' => '{}',
+          'data-title' => element['title'] || element['alt'])
 
         link = doc.document.create_element(
           'a',
diff --git a/lib/banzai/pipeline/gfm_pipeline.rb b/lib/banzai/pipeline/gfm_pipeline.rb
index 5a1f873496c..ac95a79009b 100644
--- a/lib/banzai/pipeline/gfm_pipeline.rb
+++ b/lib/banzai/pipeline/gfm_pipeline.rb
@@ -1,6 +1,12 @@
 module Banzai
   module Pipeline
     class GfmPipeline < BasePipeline
+      # These filters convert GitLab Flavored Markdown (GFM) to HTML.
+      # The handlers defined in app/assets/javascripts/copy_as_gfm.js.es6
+      # consequently convert that same HTML to GFM to be copied to the clipboard.
+      # Every filter that generates HTML from GFM should have a handler in
+      # app/assets/javascripts/copy_as_gfm.js.es6, in reverse order.
+      # The GFM-to-HTML-to-GFM cycle is tested in spec/features/copy_as_gfm_spec.rb.
       def self.filters
         @filters ||= FilterArray[
           Filter::SyntaxHighlightFilter,