Add tests of failing behaviour of some @Property inference

Ref pylint-dev#940. Would cause `Enum.__members__` to fail for enum classes
defined as subclasses of `enum.Enum`

tests/unittest_scoped_nodes.py

@@ -1923,6 +1923,95 @@ def update(self):
         builder.parse(data)
 
 
+def test_issue940_metaclass_subclass_property():
+    node = builder.extract_node(
+        """
+    class BaseMeta(type):
+        @property
+        def __members__(cls):
+            return ['a', 'property']
+    class Parent(metaclass=BaseMeta):
+        pass
+    class Derived(Parent):
+        pass
+    Derived.__members__
+    """
+    )
+    inferred = next(node.infer())
+    assert isinstance(inferred, nodes.List)
+    assert [c.value for c in inferred.elts] == ['a', 'property']
+
+
+def test_issue940_property_grandchild():
+    node = builder.extract_node(
+        """
+    class Grandparent:
+        @property
+        def __members__(self):
+            return ['a', 'property']
+    class Parent(Grandparent):
+        pass
+    class Child(Parent):
+        pass
+    Child().__members__
+    """
+    )
+    inferred = next(node.infer())
+    assert isinstance(inferred, nodes.List)
+    assert [c.value for c in inferred.elts] == ['a', 'property']
+
+
+def test_issue940_metaclass_property():
+    node = builder.extract_node(
+        """
+    class BaseMeta(type):
+        @property
+        def __members__(cls):
+            return ['a', 'property']
+    class Parent(metaclass=BaseMeta):
+        pass
+    Parent.__members__
+    """
+    )
+    inferred = next(node.infer())
+    assert isinstance(inferred, nodes.List)
+    assert [c.value for c in inferred.elts] == ['a', 'property']
+
+
+def test_issue940_metaclass_values_funcdef():
+    node = builder.extract_node(
+        """
+    class BaseMeta(type):
+        def __members__(cls):
+            return ['a', 'func']
+    class Parent(metaclass=BaseMeta):
+        pass
+    Parent.__members__()
+    """
+    )
+    inferred = next(node.infer())
+    assert isinstance(inferred, nodes.List)
+    assert [c.value for c in inferred.elts] == ['a', 'func']
+
+
+def test_issue940_metaclass_derived_funcdef():
+    node = builder.extract_node(
+        """
+    class BaseMeta(type):
+        def __members__(cls):
+            return ['a', 'func']
+    class Parent(metaclass=BaseMeta):
+        pass
+    class Derived(Parent):
+        pass
+    Derived.__members__()
+    """
+    )
+    inferred_result = next(node.infer())
+    assert isinstance(inferred_result, nodes.List)
+    assert [c.value for c in inferred_result.elts] == ['a', 'func']
+
+
 def test_metaclass_cannot_infer_call_yields_an_instance():
     node = builder.extract_node(
         """