1 files changed, 23 insertions, 54 deletions

diff --git a/app/helpers/notes_helper.rb b/app/helpers/notes_helper.rb
index b0331f36a2f..eab0738a368 100644
--- a/app/helpers/notes_helper.rb
+++ b/app/helpers/notes_helper.rb
@@ -24,57 +24,24 @@ module NotesHelper
   end
 
   def diff_view_data
-    return {} unless @comments_target
+    return {} unless @new_diff_note_attrs
 
-    @comments_target.slice(:noteable_id, :noteable_type, :commit_id)
+    @new_diff_note_attrs.slice(:noteable_id, :noteable_type, :commit_id)
   end
 
   def diff_view_line_data(line_code, position, line_type)
     return if @diff_notes_disabled
 
-    use_legacy_diff_note = @use_legacy_diff_notes
-    # If the controller doesn't force the use of legacy diff notes, we
-    # determine this on a line-by-line basis by seeing if there already exist
-    # active legacy diff notes at this line, in which case newly created notes
-    # will use the legacy technology as well.
-    # We do this because the discussion_id values of legacy and "new" diff
-    # notes, which are used to group notes on the merge request discussion tab,
-    # are incompatible.
-    # If we didn't, diff notes that would show for the same line on the changes
-    # tab, would show in different discussions on the discussion tab.
-    use_legacy_diff_note ||= begin
-      discussion = @grouped_diff_discussions[line_code]
-      discussion && discussion.legacy_diff_discussion?
-    end
-
     data = {
       line_code: line_code,
       line_type: line_type,
     }
 
-    if use_legacy_diff_note
-      discussion_id = LegacyDiffNote.discussion_id(
-        @comments_target[:noteable_type],
-        @comments_target[:noteable_id] || @comments_target[:commit_id],
-        line_code
-      )
-
-      data.merge!(
-        note_type: LegacyDiffNote.name,
-        discussion_id: discussion_id
-      )
+    if @use_legacy_diff_notes
+      data[:note_type] = LegacyDiffNote.name
     else
-      discussion_id = DiffNote.discussion_id(
-        @comments_target[:noteable_type],
-        @comments_target[:noteable_id] || @comments_target[:commit_id],
-        position
-      )
-
-      data.merge!(
-        position: position.to_json,
-        note_type: DiffNote.name,
-        discussion_id: discussion_id
-      )
+      data[:note_type] = DiffNote.name
+      data[:position] = position.to_json
     end
 
     data
@@ -83,32 +50,34 @@ module NotesHelper
   def link_to_reply_discussion(discussion, line_type = nil)
     return unless current_user
 
-    data = discussion.reply_attributes.merge(line_type: line_type)
+    data = { discussion_id: discussion.id, line_type: line_type }
 
     button_tag 'Reply...', class: 'btn btn-text-field js-discussion-reply-button',
                            data: data, title: 'Add a reply'
   end
 
-  def preload_max_access_for_authors(notes, project)
-    user_ids = notes.map(&:author_id)
-    project.team.max_member_access_for_user_ids(user_ids)
-  end
-
-  def preload_noteable_for_regular_notes(notes)
-    ActiveRecord::Associations::Preloader.new.preload(notes.select { |note| !note.for_commit? }, :noteable)
-  end
-
   def note_max_access_for_user(note)
     note.project.team.human_max_access(note.author_id)
   end
 
   def discussion_diff_path(discussion)
-    return unless discussion.diff_discussion?
-
-    if discussion.for_merge_request? && discussion.active?
-      diffs_namespace_project_merge_request_path(discussion.project.namespace, discussion.project, discussion.noteable, anchor: discussion.line_code)
+    if discussion.for_merge_request? && discussion.diff_discussion?
+      if discussion.active?
+        # Without a diff ID, the link always points to the latest diff version
+        diff_id = nil
+      elsif merge_request_diff = discussion.latest_merge_request_diff
+        diff_id = merge_request_diff.id
+      else
+        # If the discussion is not active, and we cannot find the latest
+        # merge request diff for this discussion, we return no path at all.
+        return
+      end
+
+      diffs_namespace_project_merge_request_path(discussion.project.namespace, discussion.project, discussion.noteable, diff_id: diff_id, anchor: discussion.line_code)
     elsif discussion.for_commit?
-      namespace_project_commit_path(discussion.project.namespace, discussion.project, discussion.noteable, anchor: discussion.line_code)
+      anchor = discussion.line_code if discussion.diff_discussion?
+
+      namespace_project_commit_path(discussion.project.namespace, discussion.project, discussion.noteable, anchor: anchor)
     end
   end
 end