Allow commenting on older versions of the diff and comparisons between diff versionsdm-link-discussion-to-outdated-diff

1 files changed, 19 insertions, 1 deletions

diff --git a/app/models/diff_discussion.rb b/app/models/diff_discussion.rb
index 6a6466b493b..d627fbe327f 100644
--- a/app/models/diff_discussion.rb
+++ b/app/models/diff_discussion.rb
@@ -10,7 +10,6 @@ class DiffDiscussion < Discussion
 
   delegate  :position,
             :original_position,
-            :latest_merge_request_diff,
 
             to: :first_note
 
@@ -18,6 +17,25 @@ class DiffDiscussion < Discussion
     false
   end
 
+  def merge_request_version_params
+    return unless for_merge_request?
+
+    if active?
+      {}
+    else
+      diff_refs = position.diff_refs
+
+      if diff = noteable.merge_request_diff_for(diff_refs)
+        { diff_id: diff.id }
+      elsif diff = noteable.merge_request_diff_for(diff_refs.head_sha)
+        {
+          diff_id: diff.id,
+          start_sha: diff_refs.start_sha
+        }
+      end
+    end
+  end
+
   def reply_attributes
     super.merge(
       original_position: original_position.to_json,