Filter out ``Uninferable`` when inferring the call result result of a class with an uninferable ``__call__`` method.

Close PyCQA/pylint#2434

2 files changed, 15 insertions, 4 deletions

diff --git a/astroid/scoped_nodes.py b/astroid/scoped_nodes.py
index 92132a13..6b440f81 100644
--- a/astroid/scoped_nodes.py
+++ b/astroid/scoped_nodes.py
@@ -2063,11 +2063,9 @@ class ClassDef(mixins.FilterStmtsMixin, LocalsDictNodeNG,
                 dunder_call = next(metaclass.igetattr("__call__", context))
         except exceptions.AttributeInferenceError:
             pass
-        if (dunder_call is not None and
-                dunder_call.qname() != "builtins.type.__call__"):
+        if dunder_call and dunder_call.qname() != "builtins.type.__call__":
             context = contextmod.bind_context_to_node(context, self)
-            yield from dunder_call.infer_call_result(
-                caller, context)
+            yield from dunder_call.infer_call_result(caller, context)
         else:
             # Call type.__call__ if not set metaclass
             # (since type is the default metaclass)
diff --git a/astroid/tests/unittest_scoped_nodes.py b/astroid/tests/unittest_scoped_nodes.py
index 85a6256d..33f151cf 100644
--- a/astroid/tests/unittest_scoped_nodes.py
+++ b/astroid/tests/unittest_scoped_nodes.py
@@ -1799,5 +1799,18 @@ class ClassNodeTest(ModuleLoader, unittest.TestCase):
         self.assertEqual([x.arg for x in cls.keywords], ['foo', 'bar'])
 
 
+def test_metaclass_cannot_infer_call_yields_an_instance():
+    node = builder.extract_node('''
+    from undefined import Undefined
+    class Meta(type):
+        __call__ = Undefined
+    class A(metaclass=Meta):
+        pass
+    A()
+    ''')
+    inferred = next(node.infer())
+    assert isinstance(inferred, Instance)
+
+
 if __name__ == '__main__':
     unittest.main()