fix yield from return value on custom iterators (closes #15568)
diff --git a/Lib/test/test_pep380.py b/Lib/test/test_pep380.py
index 658bcb9..9569e10 100644
--- a/Lib/test/test_pep380.py
+++ b/Lib/test/test_pep380.py
@@ -940,6 +940,20 @@
for stack in spam(eggs(gen())):
self.assertTrue('spam' in stack and 'eggs' in stack)
+ def test_custom_iterator_return(self):
+ # See issue #15568
+ class MyIter:
+ def __iter__(self):
+ return self
+ def __next__(self):
+ raise StopIteration(42)
+ def gen():
+ nonlocal ret
+ ret = yield from MyIter()
+ ret = None
+ list(gen())
+ self.assertEqual(ret, 42)
+
def test_main():
from test import support
diff --git a/Misc/NEWS b/Misc/NEWS
index 6f7b0fc..d062df4 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,9 @@
Core and Builtins
-----------------
+- Issue #15568: Fix the return value of "yield from" when StopIteration is
+ raised by a custom iterator.
+
- Issue #13119: sys.stdout and sys.stderr are now using "\r\n" newline on
Windows, as Python 2.
diff --git a/Python/ceval.c b/Python/ceval.c
index 7e9318b..82bfcc6 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -1843,7 +1843,7 @@
} else {
_Py_IDENTIFIER(send);
if (u == Py_None)
- retval = PyIter_Next(x);
+ retval = Py_TYPE(x)->tp_iternext(x);
else
retval = _PyObject_CallMethodId(x, &PyId_send, "O", u);
}