Fix creating discussion when diff view is set to parallel

app/assets/javascripts/notes.js

@@ -338,7 +338,7 @@ require('./task_list');
      */
 
     Notes.prototype.renderDiscussionNote = function(note, $form) {
-      var discussionContainer, form, note_html, row, lineType, diffAvatarContainer;
+      var discussionContainer, form, row, lineType, diffAvatarContainer;
       if (!this.isNewNote(note)) {
         return;
       }
@@ -347,45 +347,37 @@ require('./task_list');
       row = form.closest("tr");
       lineType = this.isParallelView() ? form.find('#line_type').val() : 'old';
       diffAvatarContainer = row.prevAll('.line_holder').first().find('.js-avatar-container.' + lineType + '_line');
-      note_html = $(note.html);
-      note_html.renderGFM();
       // is this the first note of discussion?
       discussionContainer = $(".notes[data-discussion-id='" + note.discussion_id + "']");
       if (!discussionContainer.length) {
         discussionContainer = form.closest('.discussion').find('.notes');
       }
       if (discussionContainer.length === 0) {
+        if (note.diff_discussion_html) {
+          var $discussion = $(note.diff_discussion_html).renderGFM();
+
           if (!this.isParallelView() || row.hasClass('js-temp-notes-holder')) {
             // insert the note and the reply button after the temp row
-          row.after(note.diff_discussion_html);
-
-          // remove the note (will be added again below)
-          row.next().find(".note").remove();
+            row.after($discussion);
           } else {
             // Merge new discussion HTML in
-          var $discussion = $(note.diff_discussion_html);
             var $notes = $discussion.find('.notes[data-discussion-id="' + note.discussion_id + '"]');
             var contentContainerClass = '.' + $notes.closest('.notes_content')
               .attr('class')
               .split(' ')
               .join('.');
 
-          // remove the note (will be added again below)
-          $notes.find('.note').remove();
-
             row.find(contentContainerClass + ' .content').append($notes.closest('.content').children());
           }
-        // Before that, the container didn't exist
-        discussionContainer = $(".notes[data-discussion-id='" + note.discussion_id + "']");
-        // Add note to 'Changes' page discussions
-        discussionContainer.append(note_html);
+        }
+
         // Init discussion on 'Discussion' page if it is merge request page
         if ($('body').attr('data-page').indexOf('projects:merge_request') === 0 || !note.diff_discussion_html) {
-          $('ul.main-notes-list').append(note.discussion_html).renderGFM();
+          $('ul.main-notes-list').append($(note.discussion_html).renderGFM());
         }
       } else {
         // append new note to all matching discussions
-        discussionContainer.append(note_html);
+        discussionContainer.append($(note.html).renderGFM());
       }
 
       if (typeof gl.diffNotesCompileComponents !== 'undefined' && note.discussion_resolvable) {

app/assets/javascripts/render_gfm.js

@@ -8,6 +8,7 @@
   $.fn.renderGFM = function() {
     this.find('.js-syntax-highlight').syntaxHighlight();
     this.find('.js-render-math').renderMath();
+    return this;
   };
 
   $(document).on('ready load', function() {