Fix generation of diff line positions

lib/bitbucket_server/representation/pull_request_comment.rb

@@ -34,16 +34,26 @@ module BitbucketServer
         file_type == 'FROM'
       end
 
+      def added?
+        line_type  == 'ADDED'
+      end
+
+      def removed?
+        line_type == 'REMOVED'
+      end
+
       def new_pos
-        return unless to?
+        return if removed?
+        return unless line_position
 
-        comment_anchor['line']
+        line_position[1]
       end
 
       def old_pos
-        return unless from?
+        return if added?
+        return unless line_position
 
-        comment_anchor['line']
+        line_position[0]
       end
 
       def file_path
@@ -52,9 +62,36 @@ module BitbucketServer
 
       private
 
+      def line_type
+        comment_anchor['lineType']
+      end
+
+      def line_position
+        @line_position ||=
+          diff_hunks.each do |hunk|
+            segments = hunk.fetch('segments', [])
+            segments.each do |segment|
+              lines = segment.fetch('lines', [])
+              lines.each do |line|
+                if line['commentIds']&.include?(id)
+                  return [line['source'], line['destination']]
+                end
+              end
+            end
+        end
+      end
+
       def comment_anchor
         raw.fetch('commentAnchor', {})
       end
+
+      def diff
+        raw.fetch('diff', {})
+      end
+
+      def diff_hunks
+        diff.fetch('hunks', [])
+      end
     end
   end
 end

lib/gitlab/bitbucket_server_import/importer.rb

@@ -143,7 +143,7 @@ module Gitlab
             attributes = pull_request_comment_attributes(reply)
             attributes.merge!(
               position: build_position(merge_request, comment),
-              line_code: line_code_map.fetch(reply.id)
+              line_code: line_code_map.fetch(reply.id),
               discussion_id: parent.discussion_id,
               type: 'DiffNote')
             merge_request.notes.create!(attributes)