Issue #24400: Resurrect inspect.isawaitable()
collections.abc.Awaitable and collections.abc.Coroutine no longer
use __instancecheck__ hook to detect generator-based coroutines.
inspect.isawaitable() can be used to detect generator-based coroutines
and to distinguish them from regular generator objects.
diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py
index ab2b733..fbaf712 100644
--- a/Lib/test/test_collections.py
+++ b/Lib/test/test_collections.py
@@ -511,8 +511,10 @@
self.assertTrue(issubclass(type(x), Awaitable))
c = coro()
- self.assertIsInstance(c, Awaitable)
- c.close() # awoid RuntimeWarning that coro() was not awaited
+ # Iterable coroutines (generators with CO_ITERABLE_COROUTINE
+ # flag don't have '__await__' method, hence can't be instances
+ # of Awaitable. Use inspect.isawaitable to detect them.
+ self.assertNotIsInstance(c, Awaitable)
c = new_coro()
self.assertIsInstance(c, Awaitable)
@@ -559,8 +561,10 @@
self.assertTrue(issubclass(type(x), Awaitable))
c = coro()
- self.assertIsInstance(c, Coroutine)
- c.close() # awoid RuntimeWarning that coro() was not awaited
+ # Iterable coroutines (generators with CO_ITERABLE_COROUTINE
+ # flag don't have '__await__' method, hence can't be instances
+ # of Coroutine. Use inspect.isawaitable to detect them.
+ self.assertNotIsInstance(c, Coroutine)
c = new_coro()
self.assertIsInstance(c, Coroutine)
diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
index ab22c7d..a02f2e1 100644
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -151,6 +151,29 @@
coro.close(); gen_coro.close() # silence warnings
+ def test_isawaitable(self):
+ def gen(): yield
+ self.assertFalse(inspect.isawaitable(gen()))
+
+ coro = coroutine_function_example(1)
+ gen_coro = gen_coroutine_function_example(1)
+
+ self.assertTrue(inspect.isawaitable(coro))
+ self.assertTrue(inspect.isawaitable(gen_coro))
+
+ class Future:
+ def __await__():
+ pass
+ self.assertTrue(inspect.isawaitable(Future()))
+ self.assertFalse(inspect.isawaitable(Future))
+
+ class NotFuture: pass
+ not_fut = NotFuture()
+ not_fut.__await__ = lambda: None
+ self.assertFalse(inspect.isawaitable(not_fut))
+
+ coro.close(); gen_coro.close() # silence warnings
+
def test_isroutine(self):
self.assertTrue(inspect.isroutine(mod.spam))
self.assertTrue(inspect.isroutine([].count))
diff --git a/Lib/test/test_types.py b/Lib/test/test_types.py
index ba8a1b9..738588e 100644
--- a/Lib/test/test_types.py
+++ b/Lib/test/test_types.py
@@ -1447,6 +1447,19 @@
with self.assertRaisesRegex(Exception, 'ham'):
wrapper.throw(Exception, Exception('ham'))
+ def test_returning_itercoro(self):
+ @types.coroutine
+ def gen():
+ yield
+
+ gencoro = gen()
+
+ @types.coroutine
+ def foo():
+ return gencoro
+
+ self.assertIs(foo(), gencoro)
+
def test_genfunc(self):
def gen(): yield
self.assertIs(types.coroutine(gen), gen)
@@ -1457,9 +1470,6 @@
g = gen()
self.assertTrue(g.gi_code.co_flags & inspect.CO_ITERABLE_COROUTINE)
self.assertFalse(g.gi_code.co_flags & inspect.CO_COROUTINE)
- self.assertIsInstance(g, collections.abc.Coroutine)
- self.assertIsInstance(g, collections.abc.Awaitable)
- g.close() # silence warning
self.assertIs(types.coroutine(gen), gen)