mirror of https://github.com/python/cpython
739 lines
24 KiB
Python
739 lines
24 KiB
Python
import asyncio
|
|
from contextlib import (
|
|
asynccontextmanager, AbstractAsyncContextManager,
|
|
AsyncExitStack, nullcontext, aclosing, contextmanager)
|
|
from test import support
|
|
import unittest
|
|
import traceback
|
|
|
|
from test.test_contextlib import TestBaseExitStack
|
|
|
|
support.requires_working_socket(module=True)
|
|
|
|
def tearDownModule():
|
|
asyncio.set_event_loop_policy(None)
|
|
|
|
|
|
class TestAbstractAsyncContextManager(unittest.IsolatedAsyncioTestCase):
|
|
|
|
async def test_enter(self):
|
|
class DefaultEnter(AbstractAsyncContextManager):
|
|
async def __aexit__(self, *args):
|
|
await super().__aexit__(*args)
|
|
|
|
manager = DefaultEnter()
|
|
self.assertIs(await manager.__aenter__(), manager)
|
|
|
|
async with manager as context:
|
|
self.assertIs(manager, context)
|
|
|
|
async def test_slots(self):
|
|
class DefaultAsyncContextManager(AbstractAsyncContextManager):
|
|
__slots__ = ()
|
|
|
|
async def __aexit__(self, *args):
|
|
await super().__aexit__(*args)
|
|
|
|
with self.assertRaises(AttributeError):
|
|
manager = DefaultAsyncContextManager()
|
|
manager.var = 42
|
|
|
|
async def test_async_gen_propagates_generator_exit(self):
|
|
# A regression test for https://bugs.python.org/issue33786.
|
|
|
|
@asynccontextmanager
|
|
async def ctx():
|
|
yield
|
|
|
|
async def gen():
|
|
async with ctx():
|
|
yield 11
|
|
|
|
g = gen()
|
|
async for val in g:
|
|
self.assertEqual(val, 11)
|
|
break
|
|
await g.aclose()
|
|
|
|
def test_exit_is_abstract(self):
|
|
class MissingAexit(AbstractAsyncContextManager):
|
|
pass
|
|
|
|
with self.assertRaises(TypeError):
|
|
MissingAexit()
|
|
|
|
def test_structural_subclassing(self):
|
|
class ManagerFromScratch:
|
|
async def __aenter__(self):
|
|
return self
|
|
async def __aexit__(self, exc_type, exc_value, traceback):
|
|
return None
|
|
|
|
self.assertTrue(issubclass(ManagerFromScratch, AbstractAsyncContextManager))
|
|
|
|
class DefaultEnter(AbstractAsyncContextManager):
|
|
async def __aexit__(self, *args):
|
|
await super().__aexit__(*args)
|
|
|
|
self.assertTrue(issubclass(DefaultEnter, AbstractAsyncContextManager))
|
|
|
|
class NoneAenter(ManagerFromScratch):
|
|
__aenter__ = None
|
|
|
|
self.assertFalse(issubclass(NoneAenter, AbstractAsyncContextManager))
|
|
|
|
class NoneAexit(ManagerFromScratch):
|
|
__aexit__ = None
|
|
|
|
self.assertFalse(issubclass(NoneAexit, AbstractAsyncContextManager))
|
|
|
|
|
|
class AsyncContextManagerTestCase(unittest.IsolatedAsyncioTestCase):
|
|
|
|
async def test_contextmanager_plain(self):
|
|
state = []
|
|
@asynccontextmanager
|
|
async def woohoo():
|
|
state.append(1)
|
|
yield 42
|
|
state.append(999)
|
|
async with woohoo() as x:
|
|
self.assertEqual(state, [1])
|
|
self.assertEqual(x, 42)
|
|
state.append(x)
|
|
self.assertEqual(state, [1, 42, 999])
|
|
|
|
async def test_contextmanager_finally(self):
|
|
state = []
|
|
@asynccontextmanager
|
|
async def woohoo():
|
|
state.append(1)
|
|
try:
|
|
yield 42
|
|
finally:
|
|
state.append(999)
|
|
with self.assertRaises(ZeroDivisionError):
|
|
async with woohoo() as x:
|
|
self.assertEqual(state, [1])
|
|
self.assertEqual(x, 42)
|
|
state.append(x)
|
|
raise ZeroDivisionError()
|
|
self.assertEqual(state, [1, 42, 999])
|
|
|
|
async def test_contextmanager_traceback(self):
|
|
@asynccontextmanager
|
|
async def f():
|
|
yield
|
|
|
|
try:
|
|
async with f():
|
|
1/0
|
|
except ZeroDivisionError as e:
|
|
frames = traceback.extract_tb(e.__traceback__)
|
|
|
|
self.assertEqual(len(frames), 1)
|
|
self.assertEqual(frames[0].name, 'test_contextmanager_traceback')
|
|
self.assertEqual(frames[0].line, '1/0')
|
|
|
|
# Repeat with RuntimeError (which goes through a different code path)
|
|
class RuntimeErrorSubclass(RuntimeError):
|
|
pass
|
|
|
|
try:
|
|
async with f():
|
|
raise RuntimeErrorSubclass(42)
|
|
except RuntimeErrorSubclass as e:
|
|
frames = traceback.extract_tb(e.__traceback__)
|
|
|
|
self.assertEqual(len(frames), 1)
|
|
self.assertEqual(frames[0].name, 'test_contextmanager_traceback')
|
|
self.assertEqual(frames[0].line, 'raise RuntimeErrorSubclass(42)')
|
|
|
|
class StopIterationSubclass(StopIteration):
|
|
pass
|
|
|
|
class StopAsyncIterationSubclass(StopAsyncIteration):
|
|
pass
|
|
|
|
for stop_exc in (
|
|
StopIteration('spam'),
|
|
StopAsyncIteration('ham'),
|
|
StopIterationSubclass('spam'),
|
|
StopAsyncIterationSubclass('spam')
|
|
):
|
|
with self.subTest(type=type(stop_exc)):
|
|
try:
|
|
async with f():
|
|
raise stop_exc
|
|
except type(stop_exc) as e:
|
|
self.assertIs(e, stop_exc)
|
|
frames = traceback.extract_tb(e.__traceback__)
|
|
else:
|
|
self.fail(f'{stop_exc} was suppressed')
|
|
|
|
self.assertEqual(len(frames), 1)
|
|
self.assertEqual(frames[0].name, 'test_contextmanager_traceback')
|
|
self.assertEqual(frames[0].line, 'raise stop_exc')
|
|
|
|
async def test_contextmanager_no_reraise(self):
|
|
@asynccontextmanager
|
|
async def whee():
|
|
yield
|
|
ctx = whee()
|
|
await ctx.__aenter__()
|
|
# Calling __aexit__ should not result in an exception
|
|
self.assertFalse(await ctx.__aexit__(TypeError, TypeError("foo"), None))
|
|
|
|
async def test_contextmanager_trap_yield_after_throw(self):
|
|
@asynccontextmanager
|
|
async def whoo():
|
|
try:
|
|
yield
|
|
except:
|
|
yield
|
|
ctx = whoo()
|
|
await ctx.__aenter__()
|
|
with self.assertRaises(RuntimeError):
|
|
await ctx.__aexit__(TypeError, TypeError('foo'), None)
|
|
if support.check_impl_detail(cpython=True):
|
|
# The "gen" attribute is an implementation detail.
|
|
self.assertFalse(ctx.gen.ag_suspended)
|
|
|
|
async def test_contextmanager_trap_no_yield(self):
|
|
@asynccontextmanager
|
|
async def whoo():
|
|
if False:
|
|
yield
|
|
ctx = whoo()
|
|
with self.assertRaises(RuntimeError):
|
|
await ctx.__aenter__()
|
|
|
|
async def test_contextmanager_trap_second_yield(self):
|
|
@asynccontextmanager
|
|
async def whoo():
|
|
yield
|
|
yield
|
|
ctx = whoo()
|
|
await ctx.__aenter__()
|
|
with self.assertRaises(RuntimeError):
|
|
await ctx.__aexit__(None, None, None)
|
|
if support.check_impl_detail(cpython=True):
|
|
# The "gen" attribute is an implementation detail.
|
|
self.assertFalse(ctx.gen.ag_suspended)
|
|
|
|
async def test_contextmanager_non_normalised(self):
|
|
@asynccontextmanager
|
|
async def whoo():
|
|
try:
|
|
yield
|
|
except RuntimeError:
|
|
raise SyntaxError
|
|
|
|
ctx = whoo()
|
|
await ctx.__aenter__()
|
|
with self.assertRaises(SyntaxError):
|
|
await ctx.__aexit__(RuntimeError, None, None)
|
|
|
|
async def test_contextmanager_except(self):
|
|
state = []
|
|
@asynccontextmanager
|
|
async def woohoo():
|
|
state.append(1)
|
|
try:
|
|
yield 42
|
|
except ZeroDivisionError as e:
|
|
state.append(e.args[0])
|
|
self.assertEqual(state, [1, 42, 999])
|
|
async with woohoo() as x:
|
|
self.assertEqual(state, [1])
|
|
self.assertEqual(x, 42)
|
|
state.append(x)
|
|
raise ZeroDivisionError(999)
|
|
self.assertEqual(state, [1, 42, 999])
|
|
|
|
async def test_contextmanager_except_stopiter(self):
|
|
@asynccontextmanager
|
|
async def woohoo():
|
|
yield
|
|
|
|
class StopIterationSubclass(StopIteration):
|
|
pass
|
|
|
|
class StopAsyncIterationSubclass(StopAsyncIteration):
|
|
pass
|
|
|
|
for stop_exc in (
|
|
StopIteration('spam'),
|
|
StopAsyncIteration('ham'),
|
|
StopIterationSubclass('spam'),
|
|
StopAsyncIterationSubclass('spam')
|
|
):
|
|
with self.subTest(type=type(stop_exc)):
|
|
try:
|
|
async with woohoo():
|
|
raise stop_exc
|
|
except Exception as ex:
|
|
self.assertIs(ex, stop_exc)
|
|
else:
|
|
self.fail(f'{stop_exc} was suppressed')
|
|
|
|
async def test_contextmanager_wrap_runtimeerror(self):
|
|
@asynccontextmanager
|
|
async def woohoo():
|
|
try:
|
|
yield
|
|
except Exception as exc:
|
|
raise RuntimeError(f'caught {exc}') from exc
|
|
|
|
with self.assertRaises(RuntimeError):
|
|
async with woohoo():
|
|
1 / 0
|
|
|
|
# If the context manager wrapped StopAsyncIteration in a RuntimeError,
|
|
# we also unwrap it, because we can't tell whether the wrapping was
|
|
# done by the generator machinery or by the generator itself.
|
|
with self.assertRaises(StopAsyncIteration):
|
|
async with woohoo():
|
|
raise StopAsyncIteration
|
|
|
|
def _create_contextmanager_attribs(self):
|
|
def attribs(**kw):
|
|
def decorate(func):
|
|
for k,v in kw.items():
|
|
setattr(func,k,v)
|
|
return func
|
|
return decorate
|
|
@asynccontextmanager
|
|
@attribs(foo='bar')
|
|
async def baz(spam):
|
|
"""Whee!"""
|
|
yield
|
|
return baz
|
|
|
|
def test_contextmanager_attribs(self):
|
|
baz = self._create_contextmanager_attribs()
|
|
self.assertEqual(baz.__name__,'baz')
|
|
self.assertEqual(baz.foo, 'bar')
|
|
|
|
@support.requires_docstrings
|
|
def test_contextmanager_doc_attrib(self):
|
|
baz = self._create_contextmanager_attribs()
|
|
self.assertEqual(baz.__doc__, "Whee!")
|
|
|
|
@support.requires_docstrings
|
|
async def test_instance_docstring_given_cm_docstring(self):
|
|
baz = self._create_contextmanager_attribs()(None)
|
|
self.assertEqual(baz.__doc__, "Whee!")
|
|
async with baz:
|
|
pass # suppress warning
|
|
|
|
async def test_keywords(self):
|
|
# Ensure no keyword arguments are inhibited
|
|
@asynccontextmanager
|
|
async def woohoo(self, func, args, kwds):
|
|
yield (self, func, args, kwds)
|
|
async with woohoo(self=11, func=22, args=33, kwds=44) as target:
|
|
self.assertEqual(target, (11, 22, 33, 44))
|
|
|
|
async def test_recursive(self):
|
|
depth = 0
|
|
ncols = 0
|
|
|
|
@asynccontextmanager
|
|
async def woohoo():
|
|
nonlocal ncols
|
|
ncols += 1
|
|
|
|
nonlocal depth
|
|
before = depth
|
|
depth += 1
|
|
yield
|
|
depth -= 1
|
|
self.assertEqual(depth, before)
|
|
|
|
@woohoo()
|
|
async def recursive():
|
|
if depth < 10:
|
|
await recursive()
|
|
|
|
await recursive()
|
|
|
|
self.assertEqual(ncols, 10)
|
|
self.assertEqual(depth, 0)
|
|
|
|
async def test_decorator(self):
|
|
entered = False
|
|
|
|
@asynccontextmanager
|
|
async def context():
|
|
nonlocal entered
|
|
entered = True
|
|
yield
|
|
entered = False
|
|
|
|
@context()
|
|
async def test():
|
|
self.assertTrue(entered)
|
|
|
|
self.assertFalse(entered)
|
|
await test()
|
|
self.assertFalse(entered)
|
|
|
|
async def test_decorator_with_exception(self):
|
|
entered = False
|
|
|
|
@asynccontextmanager
|
|
async def context():
|
|
nonlocal entered
|
|
try:
|
|
entered = True
|
|
yield
|
|
finally:
|
|
entered = False
|
|
|
|
@context()
|
|
async def test():
|
|
self.assertTrue(entered)
|
|
raise NameError('foo')
|
|
|
|
self.assertFalse(entered)
|
|
with self.assertRaisesRegex(NameError, 'foo'):
|
|
await test()
|
|
self.assertFalse(entered)
|
|
|
|
async def test_decorating_method(self):
|
|
|
|
@asynccontextmanager
|
|
async def context():
|
|
yield
|
|
|
|
|
|
class Test(object):
|
|
|
|
@context()
|
|
async def method(self, a, b, c=None):
|
|
self.a = a
|
|
self.b = b
|
|
self.c = c
|
|
|
|
# these tests are for argument passing when used as a decorator
|
|
test = Test()
|
|
await test.method(1, 2)
|
|
self.assertEqual(test.a, 1)
|
|
self.assertEqual(test.b, 2)
|
|
self.assertEqual(test.c, None)
|
|
|
|
test = Test()
|
|
await test.method('a', 'b', 'c')
|
|
self.assertEqual(test.a, 'a')
|
|
self.assertEqual(test.b, 'b')
|
|
self.assertEqual(test.c, 'c')
|
|
|
|
test = Test()
|
|
await test.method(a=1, b=2)
|
|
self.assertEqual(test.a, 1)
|
|
self.assertEqual(test.b, 2)
|
|
|
|
|
|
class AclosingTestCase(unittest.IsolatedAsyncioTestCase):
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docs(self):
|
|
cm_docstring = aclosing.__doc__
|
|
obj = aclosing(None)
|
|
self.assertEqual(obj.__doc__, cm_docstring)
|
|
|
|
async def test_aclosing(self):
|
|
state = []
|
|
class C:
|
|
async def aclose(self):
|
|
state.append(1)
|
|
x = C()
|
|
self.assertEqual(state, [])
|
|
async with aclosing(x) as y:
|
|
self.assertEqual(x, y)
|
|
self.assertEqual(state, [1])
|
|
|
|
async def test_aclosing_error(self):
|
|
state = []
|
|
class C:
|
|
async def aclose(self):
|
|
state.append(1)
|
|
x = C()
|
|
self.assertEqual(state, [])
|
|
with self.assertRaises(ZeroDivisionError):
|
|
async with aclosing(x) as y:
|
|
self.assertEqual(x, y)
|
|
1 / 0
|
|
self.assertEqual(state, [1])
|
|
|
|
async def test_aclosing_bpo41229(self):
|
|
state = []
|
|
|
|
@contextmanager
|
|
def sync_resource():
|
|
try:
|
|
yield
|
|
finally:
|
|
state.append(1)
|
|
|
|
async def agenfunc():
|
|
with sync_resource():
|
|
yield -1
|
|
yield -2
|
|
|
|
x = agenfunc()
|
|
self.assertEqual(state, [])
|
|
with self.assertRaises(ZeroDivisionError):
|
|
async with aclosing(x) as y:
|
|
self.assertEqual(x, y)
|
|
self.assertEqual(-1, await x.__anext__())
|
|
1 / 0
|
|
self.assertEqual(state, [1])
|
|
|
|
|
|
class TestAsyncExitStack(TestBaseExitStack, unittest.IsolatedAsyncioTestCase):
|
|
class SyncAsyncExitStack(AsyncExitStack):
|
|
@staticmethod
|
|
def run_coroutine(coro):
|
|
loop = asyncio.get_event_loop_policy().get_event_loop()
|
|
t = loop.create_task(coro)
|
|
t.add_done_callback(lambda f: loop.stop())
|
|
loop.run_forever()
|
|
|
|
exc = t.exception()
|
|
if not exc:
|
|
return t.result()
|
|
else:
|
|
context = exc.__context__
|
|
|
|
try:
|
|
raise exc
|
|
except:
|
|
exc.__context__ = context
|
|
raise exc
|
|
|
|
def close(self):
|
|
return self.run_coroutine(self.aclose())
|
|
|
|
def __enter__(self):
|
|
return self.run_coroutine(self.__aenter__())
|
|
|
|
def __exit__(self, *exc_details):
|
|
return self.run_coroutine(self.__aexit__(*exc_details))
|
|
|
|
exit_stack = SyncAsyncExitStack
|
|
callback_error_internal_frames = [
|
|
('__exit__', 'return self.run_coroutine(self.__aexit__(*exc_details))'),
|
|
('run_coroutine', 'raise exc'),
|
|
('run_coroutine', 'raise exc'),
|
|
('__aexit__', 'raise exc'),
|
|
('__aexit__', 'cb_suppress = cb(*exc_details)'),
|
|
]
|
|
|
|
async def test_async_callback(self):
|
|
expected = [
|
|
((), {}),
|
|
((1,), {}),
|
|
((1,2), {}),
|
|
((), dict(example=1)),
|
|
((1,), dict(example=1)),
|
|
((1,2), dict(example=1)),
|
|
]
|
|
result = []
|
|
async def _exit(*args, **kwds):
|
|
"""Test metadata propagation"""
|
|
result.append((args, kwds))
|
|
|
|
async with AsyncExitStack() as stack:
|
|
for args, kwds in reversed(expected):
|
|
if args and kwds:
|
|
f = stack.push_async_callback(_exit, *args, **kwds)
|
|
elif args:
|
|
f = stack.push_async_callback(_exit, *args)
|
|
elif kwds:
|
|
f = stack.push_async_callback(_exit, **kwds)
|
|
else:
|
|
f = stack.push_async_callback(_exit)
|
|
self.assertIs(f, _exit)
|
|
for wrapper in stack._exit_callbacks:
|
|
self.assertIs(wrapper[1].__wrapped__, _exit)
|
|
self.assertNotEqual(wrapper[1].__name__, _exit.__name__)
|
|
self.assertIsNone(wrapper[1].__doc__, _exit.__doc__)
|
|
|
|
self.assertEqual(result, expected)
|
|
|
|
result = []
|
|
async with AsyncExitStack() as stack:
|
|
with self.assertRaises(TypeError):
|
|
stack.push_async_callback(arg=1)
|
|
with self.assertRaises(TypeError):
|
|
self.exit_stack.push_async_callback(arg=2)
|
|
with self.assertRaises(TypeError):
|
|
stack.push_async_callback(callback=_exit, arg=3)
|
|
self.assertEqual(result, [])
|
|
|
|
async def test_async_push(self):
|
|
exc_raised = ZeroDivisionError
|
|
async def _expect_exc(exc_type, exc, exc_tb):
|
|
self.assertIs(exc_type, exc_raised)
|
|
async def _suppress_exc(*exc_details):
|
|
return True
|
|
async def _expect_ok(exc_type, exc, exc_tb):
|
|
self.assertIsNone(exc_type)
|
|
self.assertIsNone(exc)
|
|
self.assertIsNone(exc_tb)
|
|
class ExitCM(object):
|
|
def __init__(self, check_exc):
|
|
self.check_exc = check_exc
|
|
async def __aenter__(self):
|
|
self.fail("Should not be called!")
|
|
async def __aexit__(self, *exc_details):
|
|
await self.check_exc(*exc_details)
|
|
|
|
async with self.exit_stack() as stack:
|
|
stack.push_async_exit(_expect_ok)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _expect_ok)
|
|
cm = ExitCM(_expect_ok)
|
|
stack.push_async_exit(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1].__self__, cm)
|
|
stack.push_async_exit(_suppress_exc)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _suppress_exc)
|
|
cm = ExitCM(_expect_exc)
|
|
stack.push_async_exit(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1].__self__, cm)
|
|
stack.push_async_exit(_expect_exc)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _expect_exc)
|
|
stack.push_async_exit(_expect_exc)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _expect_exc)
|
|
1/0
|
|
|
|
async def test_enter_async_context(self):
|
|
class TestCM(object):
|
|
async def __aenter__(self):
|
|
result.append(1)
|
|
async def __aexit__(self, *exc_details):
|
|
result.append(3)
|
|
|
|
result = []
|
|
cm = TestCM()
|
|
|
|
async with AsyncExitStack() as stack:
|
|
@stack.push_async_callback # Registered first => cleaned up last
|
|
async def _exit():
|
|
result.append(4)
|
|
self.assertIsNotNone(_exit)
|
|
await stack.enter_async_context(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1].__self__, cm)
|
|
result.append(2)
|
|
|
|
self.assertEqual(result, [1, 2, 3, 4])
|
|
|
|
async def test_enter_async_context_errors(self):
|
|
class LacksEnterAndExit:
|
|
pass
|
|
class LacksEnter:
|
|
async def __aexit__(self, *exc_info):
|
|
pass
|
|
class LacksExit:
|
|
async def __aenter__(self):
|
|
pass
|
|
|
|
async with self.exit_stack() as stack:
|
|
with self.assertRaisesRegex(TypeError, 'asynchronous context manager'):
|
|
await stack.enter_async_context(LacksEnterAndExit())
|
|
with self.assertRaisesRegex(TypeError, 'asynchronous context manager'):
|
|
await stack.enter_async_context(LacksEnter())
|
|
with self.assertRaisesRegex(TypeError, 'asynchronous context manager'):
|
|
await stack.enter_async_context(LacksExit())
|
|
self.assertFalse(stack._exit_callbacks)
|
|
|
|
async def test_async_exit_exception_chaining(self):
|
|
# Ensure exception chaining matches the reference behaviour
|
|
async def raise_exc(exc):
|
|
raise exc
|
|
|
|
saved_details = None
|
|
async def suppress_exc(*exc_details):
|
|
nonlocal saved_details
|
|
saved_details = exc_details
|
|
return True
|
|
|
|
try:
|
|
async with self.exit_stack() as stack:
|
|
stack.push_async_callback(raise_exc, IndexError)
|
|
stack.push_async_callback(raise_exc, KeyError)
|
|
stack.push_async_callback(raise_exc, AttributeError)
|
|
stack.push_async_exit(suppress_exc)
|
|
stack.push_async_callback(raise_exc, ValueError)
|
|
1 / 0
|
|
except IndexError as exc:
|
|
self.assertIsInstance(exc.__context__, KeyError)
|
|
self.assertIsInstance(exc.__context__.__context__, AttributeError)
|
|
# Inner exceptions were suppressed
|
|
self.assertIsNone(exc.__context__.__context__.__context__)
|
|
else:
|
|
self.fail("Expected IndexError, but no exception was raised")
|
|
# Check the inner exceptions
|
|
inner_exc = saved_details[1]
|
|
self.assertIsInstance(inner_exc, ValueError)
|
|
self.assertIsInstance(inner_exc.__context__, ZeroDivisionError)
|
|
|
|
async def test_async_exit_exception_explicit_none_context(self):
|
|
# Ensure AsyncExitStack chaining matches actual nested `with` statements
|
|
# regarding explicit __context__ = None.
|
|
|
|
class MyException(Exception):
|
|
pass
|
|
|
|
@asynccontextmanager
|
|
async def my_cm():
|
|
try:
|
|
yield
|
|
except BaseException:
|
|
exc = MyException()
|
|
try:
|
|
raise exc
|
|
finally:
|
|
exc.__context__ = None
|
|
|
|
@asynccontextmanager
|
|
async def my_cm_with_exit_stack():
|
|
async with self.exit_stack() as stack:
|
|
await stack.enter_async_context(my_cm())
|
|
yield stack
|
|
|
|
for cm in (my_cm, my_cm_with_exit_stack):
|
|
with self.subTest():
|
|
try:
|
|
async with cm():
|
|
raise IndexError()
|
|
except MyException as exc:
|
|
self.assertIsNone(exc.__context__)
|
|
else:
|
|
self.fail("Expected IndexError, but no exception was raised")
|
|
|
|
async def test_instance_bypass_async(self):
|
|
class Example(object): pass
|
|
cm = Example()
|
|
cm.__aenter__ = object()
|
|
cm.__aexit__ = object()
|
|
stack = self.exit_stack()
|
|
with self.assertRaisesRegex(TypeError, 'asynchronous context manager'):
|
|
await stack.enter_async_context(cm)
|
|
stack.push_async_exit(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1], cm)
|
|
|
|
|
|
class TestAsyncNullcontext(unittest.IsolatedAsyncioTestCase):
|
|
async def test_async_nullcontext(self):
|
|
class C:
|
|
pass
|
|
c = C()
|
|
async with nullcontext(c) as c_in:
|
|
self.assertIs(c_in, c)
|
|
|
|
|
|
if __name__ == '__main__':
|
|
unittest.main()
|