bpo-38013: make async_generator_athrow object tolerant to throwing exceptions (GH-16070)
Even when the helper is not started yet.
This behavior follows conventional generator one.
There is no reason for `async_generator_athrow` to handle `gen.throw()` differently.
https://bugs.python.org/issue38013
diff --git a/Lib/test/test_asyncgen.py b/Lib/test/test_asyncgen.py
index 71b0968..3a8d5fd 100644
--- a/Lib/test/test_asyncgen.py
+++ b/Lib/test/test_asyncgen.py
@@ -1125,6 +1125,28 @@
res = self.loop.run_until_complete(run())
self.assertEqual(res, [i * 2 for i in range(1, 10)])
+ def test_asyncgen_nonstarted_hooks_are_cancellable(self):
+ # See https://bugs.python.org/issue38013
+ messages = []
+
+ def exception_handler(loop, context):
+ messages.append(context)
+
+ async def async_iterate():
+ yield 1
+ yield 2
+
+ async def main():
+ loop = asyncio.get_running_loop()
+ loop.set_exception_handler(exception_handler)
+
+ async for i in async_iterate():
+ break
+
+ asyncio.run(main())
+
+ self.assertEqual([], messages)
+
if __name__ == "__main__":
unittest.main()
diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-09-12-19-50-01.bpo-38013.I7btD0.rst b/Misc/NEWS.d/next/Core and Builtins/2019-09-12-19-50-01.bpo-38013.I7btD0.rst
new file mode 100644
index 0000000..a61aa48
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2019-09-12-19-50-01.bpo-38013.I7btD0.rst
@@ -0,0 +1,3 @@
+Allow to call ``async_generator_athrow().throw(...)`` even for non-started
+async generator helper. It fixes annoying warning at the end of
+:func:`asyncio.run` call.
diff --git a/Objects/genobject.c b/Objects/genobject.c
index 9f490b4..82e6e55 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -1884,11 +1884,6 @@
{
PyObject *retval;
- if (o->agt_state == AWAITABLE_STATE_INIT) {
- PyErr_SetString(PyExc_RuntimeError, NON_INIT_CORO_MSG);
- return NULL;
- }
-
if (o->agt_state == AWAITABLE_STATE_CLOSED) {
PyErr_SetNone(PyExc_StopIteration);
return NULL;