Added a couple of new Python 3 checks for accessing dict methods in non-iterable context. Part of #377

1 files changed, 32 insertions, 0 deletions

diff --git a/pylint/test/unittest_checker_python3.py b/pylint/test/unittest_checker_python3.py
index 73732cdef..910a6b71e 100644
--- a/pylint/test/unittest_checker_python3.py
+++ b/pylint/test/unittest_checker_python3.py
@@ -167,6 +167,38 @@ class TestPython3Checker(testutils.CheckerTestCase):
             self.as_argument_to_callable_constructor_test(fxn, func)
 
     @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 = {}'
+        ]
+        non_iterating_code = [
+            'x = __({}())',
+            '__({}())[0]'
+        ]
+
+        for method in ('keys', 'items', 'values'):
+            dict_method = '{{}}.{}'.format(method)
+
+            for code in iterating_code:
+                with_value = code.format(dict_method)
+                module = astroid.parse(with_value)
+                with self.assertNoMessages():
+                    self.walk(module)
+
+            for code in non_iterating_code:
+                with_value = code.format(dict_method)
+                node = astroid.extract_node(with_value)
+
+                checker = 'dict-{}-not-iterating'.format(method)
+                message = testutils.Message(checker, node=node)
+                with self.assertAddsMessages(message):
+                    self.checker.visit_call(node)
+
+    @python2_only
     def test_map_in_iterating_context(self):
         self.iterating_context_tests('map')