Add links to the note source if the note is mixed in

app/helpers/notes_helper.rb

@@ -12,5 +12,15 @@ module NotesHelper
     !@mixed_targets || @main_target_type == note.noteable_type
   end
 
+  def link_to_commit_diff_line_note(note)
+    return unless note.line_note?
+
+    commit = note.target
+    diff_index, diff_old_line, diff_new_line = note.line_code.split('_')
+
+    link_file = commit.diffs[diff_index.to_i].new_path
+    link_line = diff_new_line
+
+    link_to "#{link_file}:L#{link_line}", project_commit_path(@project, commit, anchor: note.line_code)
   end
 end

app/views/commits/_text_file.html.haml

@@ -4,7 +4,7 @@
 
 %table{class: "#{'hide' if too_big}"}
   - each_diff_line(diff.diff.lines.to_a, index) do |line, type, line_code, line_new, line_old|
-    %tr.line_holder
+    %tr.line_holder{ id: line_code }
       - if type == "match"
         %td.old_line= "..."
         %td.new_line= "..."

app/views/notes/_note.html.haml

@@ -7,6 +7,12 @@
         = time_ago_in_words(note.updated_at)
         ago
 
+    - unless note_for_main_target?(note)
+      - if note.commit?
+        %span.cgray
+          on #{link_to note.target.short_id, project_commit_path(@project, note.target)}
+          = link_to_commit_diff_line_note(note) if note.line_note?
+
     -# only show vote if it's a note for the main target
     - if note_for_main_target?(note)
       - if note.upvote?