File isinstance_w_gen_prot_subcls.patch of Package python-typing.15192

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File isinstance_w_gen_prot_subcls.patch of Package python-typing.15192

From a75292e5aa5aafb4b25207c2cc2a9d4647754bd0 Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <ilevkivskyi@dropbox.com>
Date: Thu, 22 Aug 2019 13:15:51 +0100
Subject: [PATCH 1/2] Fix isinstance() with generic protocol subclasses after
 subscripting

---
 python2/test_typing.py | 21 +++++++++++++++++++++
 python2/typing.py      | 19 +++++++++++--------
 2 files changed, 32 insertions(+), 8 deletions(-)

--- a/python2/test_typing.py
+++ b/python2/test_typing.py
@@ -749,6 +749,27 @@ class ProtocolTests(BaseTestCase):
         self.assertIsInstance(C(1), P)
         self.assertIsInstance(C(1), PG)
 
+    def test_protocol_checks_after_subscript(self):
+        class P(Protocol[T]): pass
+        class C(P[T]): pass
+        class Old1: pass
+        class New1(object): pass
+        class Old2: pass
+        class New2(object): pass
+        CA = C[Any]  # noqa
+
+        self.assertNotIsInstance(Old1(), C)
+        self.assertNotIsInstance(New1(), C)
+        self.assertNotIsSubclass(Old2, C)
+        self.assertNotIsSubclass(New2, C)
+
+        class D1(C[Any]): pass
+        class D2(C[Any]): pass
+        CI = C[int]  # noqa
+
+        self.assertIsInstance(D1(), C)
+        self.assertIsSubclass(D2, C)
+
     def test_protocols_support_register(self):
         @runtime_checkable
         class P(Protocol):
--- a/python2/typing.py
+++ b/python2/typing.py
@@ -1393,14 +1393,17 @@ class GenericMeta(TypingMeta, abc.ABCMet
 
     def __subclasscheck__(self, cls):
         if self.__origin__ is not None:
-            # This should only be modules within the standard
-            # library. singledispatch is the only exception, because
-            # it's a Python 2 backport of functools.singledispatch.
-            if sys._getframe(1).f_globals['__name__'] not in ['abc', 'functools',
-                                                              'singledispatch']:
-                raise TypeError("Parameterized generics cannot be used with class "
-                                "or instance checks")
-            return False
+            # These should only be modules within the standard library.
+            # singledispatch is an exception, because it's a Python 2 backport
+            # of functools.singledispatch.
+            whitelist = ['abc', 'functools', 'singledispatch']
+            if (sys._getframe(1).f_globals['__name__'] in whitelist or
+                    # The second frame is needed for the case where we came
+                    # from _ProtocolMeta.__subclasscheck__.
+                    sys._getframe(2).f_globals['__name__'] in whitelist):
+                return False
+            raise TypeError("Parameterized generics cannot be used with class "
+                            "or instance checks")
         if self is Generic:
             raise TypeError("Class %r cannot be used with class "
                             "or instance checks" % self)

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File isinstance_w_gen_prot_subcls.patch of Package python-typing.15192

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