From: Yury Selivanov <yselivanov@gmail.com>
Date: Sun, 12 Mar 2017 21:03:46 +0000 (-0400)
Subject: Fix wrapping into StopIteration of return values in generators and coroutines (#644... 
X-Git-Tag: v3.5.4rc1~279
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=216803d8e10615c769571fbfbd1f341557f25a14;p=thirdparty%2FPython%2Fcpython.git

Fix wrapping into StopIteration of return values in generators and coroutines (#644) (#648)
---

diff --git a/Lib/test/test_coroutines.py b/Lib/test/test_coroutines.py
index 4a327b5ba9f1..6d63cdb5f0fc 100644
--- a/Lib/test/test_coroutines.py
+++ b/Lib/test/test_coroutines.py
@@ -975,6 +975,21 @@ class CoroutineTest(unittest.TestCase):
                                     "coroutine is being awaited already"):
             waiter(coro).send(None)
 
+    def test_await_16(self):
+        # See https://bugs.python.org/issue29600 for details.
+
+        async def f():
+            return ValueError()
+
+        async def g():
+            try:
+                raise KeyError
+            except:
+                return await f()
+
+        _, result = run_async(g())
+        self.assertIsNone(result.__context__)
+
     def test_with_1(self):
         class Manager:
             def __init__(self, name):
diff --git a/Misc/NEWS b/Misc/NEWS
index 98b47bdab4a8..e56c0914b1b8 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,8 @@ Release date: XXXX-XX-XX
 Core and Builtins
 -----------------
 
+- bpo-29600: Fix wrapping coroutine return values in StopIteration.
+
 - Issue #29537: Restore runtime compatibility with bytecode files generated by
   CPython 3.5.0 to 3.5.2, and adjust the eval loop to avoid the problems that
   could be caused by the malformed variant of the BUILD_MAP_UNPACK_WITH_CALL
diff --git a/Objects/genobject.c b/Objects/genobject.c
index d403598181ab..0de540898d5e 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -466,8 +466,7 @@ _PyGen_SetStopIterationValue(PyObject *value)
     PyObject *e;
 
     if (value == NULL ||
-        (!PyTuple_Check(value) &&
-         !PyObject_TypeCheck(value, (PyTypeObject *) PyExc_StopIteration)))
+        (!PyTuple_Check(value) && !PyExceptionInstance_Check(value)))
     {
         /* Delay exception instantiation if we can */
         PyErr_SetObject(PyExc_StopIteration, value);