Handle dict subclasses for dict-not-iterating checks

1 files changed, 19 insertions, 2 deletions

diff --git a/pylint/test/unittest_checker_python3.py b/pylint/test/unittest_checker_python3.py
index f97d6e54c..12b82b0e3 100644
--- a/pylint/test/unittest_checker_python3.py
+++ b/pylint/test/unittest_checker_python3.py
@@ -181,17 +181,34 @@ class TestPython3Checker(testutils.CheckerTestCase):
             self.as_argument_to_callable_constructor_test(fxn, func)
 
     @python2_only
+    def test_dict_subclasses_methods_in_iterating_context(self):
+        iterating, not_iterating = astroid.extract_node('''
+        from __future__ import absolute_import
+        from collections import defaultdict
+        d = defaultdict(list)
+        a, b = d.keys() #@
+        x = d.keys() #@
+        ''')
+
+        with self.assertNoMessages():
+            self.checker.visit_call(iterating.value)
+
+        message = testutils.Message('dict-keys-not-iterating', node=not_iterating.value)
+        with self.assertAddsMessages(message):
+            self.checker.visit_call(not_iterating.value)
+
+    @python2_only
     def test_dict_methods_in_iterating_context(self):
         iterating_code = [
             'for x in {}: pass',
             '(x for x in {})',
             '[x for x in {}]',
             'func({})',
-            'a, b = {}'
+            'a, b = {}',
         ]
         non_iterating_code = [
             'x = __({}())',
-            '__({}())[0]'
+            '__({}())[0]',
         ]
 
         for method in ('keys', 'items', 'values'):