ensure linenumber data attribute is correct for the last line in a diff chunk

app/views/projects/blob/diff.html.haml

@@ -27,4 +27,4 @@
 
   - if @form.unfold? && @form.bottom? && @form.to < @blob.loc
     %tr.line_holder{ id: @form.to, class: line_class }
-      = diff_match_line @form.to, @form.to, text: @match_line, view: diff_view, bottom: true
+      = diff_match_line @form.to - @form.offset, @form.to, text: @match_line, view: diff_view, bottom: true

app/views/projects/diffs/_parallel_view.html.haml

 / Side-by-side diff view
 .text-file.diff-wrap-lines.code.js-syntax-highlight{ data: diff_view_data }
   %table
-    - last_line = 0
     - diff_file.parallel_diff_lines.each do |line|
       - left = line[:left]
       - right = line[:right]
-      - last_line = right.new_pos if right
       %tr.line_holder.parallel
         - if left
           - if left.meta?
@@ -37,6 +35,7 @@
         - discussion_left, discussion_right = parallel_diff_discussions(left, right, diff_file)
         - if discussion_left || discussion_right
           = render "discussions/parallel_diff_discussion", discussion_left: discussion_left, discussion_right: discussion_right
-    - if !diff_file.new_file && last_line > 0
+    - if !diff_file.new_file && diff_file.diff_lines.any?
+      - last_line = diff_file.diff_lines.last
       %tr.line_holder.parallel
-        = diff_match_line last_line, last_line, bottom: true, view: :parallel
+        = diff_match_line last_line.old_pos, last_line.new_pos, bottom: true, view: :parallel

app/views/projects/diffs/_text_file.html.haml

@@ -4,14 +4,13 @@
     %a.show-suppressed-diff.js-show-suppressed-diff Changes suppressed. Click to show.
 
 %table.text-file.code.js-syntax-highlight{ data: diff_view_data, class: too_big ? 'hide' : '' }
-  - last_line = 0
   - discussions = @grouped_diff_discussions unless @diff_notes_disabled
   = render partial: "projects/diffs/line",
     collection: diff_file.highlighted_diff_lines,
     as: :line,
     locals: { diff_file: diff_file, discussions: discussions }
 
-  - last_line = diff_file.highlighted_diff_lines.last.new_pos
-  - if !diff_file.new_file && last_line > 0
+  - if !diff_file.new_file && diff_file.highlighted_diff_lines.any?
+    - last_line = diff_file.highlighted_diff_lines.last
     %tr.line_holder
-      = diff_match_line last_line, last_line, bottom: true
+      = diff_match_line last_line.old_pos, last_line.new_pos, bottom: true