Diff parser: Make sure dedent start pos are matching

test/test_diff_parser.py

@@ -47,7 +47,7 @@ def _assert_nodes_are_equal(node1, node2):
         assert node1.value == node2.value
         #assert node1.type == node2.type
         assert node1.prefix == node2.prefix
-        #assert node1.start_pos == node2.start_pos
+        assert node1.start_pos == node2.start_pos
         return
     else:
         try: