Fix regression in previous commit on _ListProxy transformations (fixes #213)

mwparserfromhell/wikicode.py

@@ -111,16 +111,19 @@ class Wikicode(StringMixIn):
 
     def _is_child_wikicode(self, obj, recursive=True):
         """Return whether the given :class:`.Wikicode` is a descendant."""
-        nodes = obj.nodes
-        if isinstance(nodes, _ListProxy):
-            nodes = nodes._parent  # pylint: disable=protected-access
-        if nodes is self.nodes:
+        def deref(nodes):
+            if isinstance(nodes, _ListProxy):
+                return nodes._parent  # pylint: disable=protected-access
+            return nodes
+
+        target = deref(obj.nodes)
+        if target is deref(self.nodes):
             return True
         if recursive:
             todo = [self]
             while todo:
                 code = todo.pop()
-                if nodes is code.nodes:
+                if target is deref(code.nodes):
                     return True
                 for node in code.nodes:
                     todo += list(node.__children__())

tests/test_wikicode.py

@@ -225,6 +225,13 @@ class TestWikicode(TreeEqualityTestCase):
         func(sec2, "\nbody")
         self.assertEqual(expected[7], code8)
 
+        code9 = parse("{{foo}}")
+        meth(code9.get_sections()[0], code9.get_sections()[0], "{{bar}}")
+        meth(code9.get_sections()[0], code9, "{{baz}}")
+        meth(code9, code9, "{{qux}}")
+        meth(code9, code9.get_sections()[0], "{{quz}}")
+        self.assertEqual(expected[8], code9)
+
     def test_insert_before(self):
         """test Wikicode.insert_before()"""
         meth = lambda code, *args, **kw: code.insert_before(*args, **kw)
@@ -237,6 +244,7 @@ class TestWikicode(TreeEqualityTestCase):
             "here cdis {{some abtext and a {{template}}}}",
             "{{foo}}{{bar}}{{baz}}{{lol}}{{foo}}{{baz}}",
             "lead\n== header ==\nbody",
+            "{{quz}}{{qux}}{{baz}}{{bar}}{{foo}}",
         ]
         self._test_search(meth, expected)
 
@@ -252,6 +260,7 @@ class TestWikicode(TreeEqualityTestCase):
             "here is {{somecd text andab a {{template}}}}",
             "{{foo}}{{bar}}{{baz}}{{foo}}{{baz}}{{lol}}",
             "lead\n== header ==\nbody",
+            "{{foo}}{{bar}}{{baz}}{{qux}}{{quz}}",
         ]
         self._test_search(meth, expected)
 
@@ -267,6 +276,7 @@ class TestWikicode(TreeEqualityTestCase):
             "here cd ab a {{template}}}}",
             "{{foo}}{{bar}}{{baz}}{{lol}}",
             "lead\n== header ==\nbody",
+            "{{quz}}",
         ]
         self._test_search(meth, expected)
 
@@ -294,6 +304,7 @@ class TestWikicode(TreeEqualityTestCase):
             "here   a {{template}}}}",
             "{{foo}}{{bar}}{{baz}}",
             "== header ==",
+            "",
         ]
         self._test_search(meth, expected)