Capturing exceptions into names can lead to reference cycles though the __traceback__ attribute of the exceptions in some obscure cases that have been reported previously and fixed individually. As these variables are not used anyway, we can remove the binding to reduce the chances of creating reference cycles.
See for example GH-13135
Add explicit `asyncSetUp` and `asyncTearDown` methods.
The rest is the same as for #13228
`AsyncTestCase` create a loop instance for every test for the sake of test isolation.
Sometimes a loop shared between all tests can speed up tests execution time a lot but it requires control of closed resources after every test finish. Basically, it requires nested supervisors support that was discussed with @1st1 many times. Sorry, asyncio supervisors have no chance to land on Python 3.8.
The PR intentionally does not provide API for changing the used event loop or getting the test loop: use `asyncio.set_event_loop_policy()` and `asyncio.get_event_loop()` instead.
The PR adds four overridable methods to base `unittest.TestCase` class:
```
def _callSetUp(self):
self.setUp()
def _callTestMethod(self, method):
method()
def _callTearDown(self):
self.tearDown()
def _callCleanup(self, function, /, *args, **kwargs):
function(*args, **kwargs)
```
It allows using asyncio facilities with minimal influence on the unittest code.
The last but not least: the PR respects contextvars. The context variable installed by `asyncSetUp` is available on test, `tearDown` and a coroutine scheduled by `addCleanup`.
https://bugs.python.org/issue32972
Deprecated passing the following arguments as keyword arguments:
- "func" in functools.partialmethod(), weakref.finalize(),
profile.Profile.runcall(), cProfile.Profile.runcall(),
bdb.Bdb.runcall(), trace.Trace.runfunc() and
curses.wrapper().
- "function" in unittest.addModuleCleanup() and
unittest.TestCase.addCleanup().
- "fn" in the submit() method of concurrent.futures.ThreadPoolExecutor
and concurrent.futures.ProcessPoolExecutor.
- "callback" in contextlib.ExitStack.callback(),
contextlib.AsyncExitStack.callback() and
contextlib.AsyncExitStack.push_async_callback().
- "c" and "typeid" in the create() method of multiprocessing.managers.Server
and multiprocessing.managers.SharedMemoryServer.
- "obj" in weakref.finalize().
Also allowed to pass arbitrary keyword arguments (even "self" and "func")
if the above arguments are passed as positional argument.
* #30190 / unittest / assertAlmostEqual(delta=...) / error msg: show the difference between the 2 numbers in case of failure
* safe_repr() diff
* also show difference when passing 'places' argument
* refactoring
* update Misc/NEWS
Previously a non-string, non-regex second argument and missing callable
argument could cause the test to appear to always pass.
Initial patch by Kamilla Holanda.
Serhiy Storchaka
Batuhan Taşkaya
Steve Cirelli
Pablo Galindo
Naitree Zhu
Andrew Svetlov
jkleint
Lisa Roach
Bruno Oliveira
Ron
Giampaolo Rodola
Victor Stinner
Berker Peksag
Martin Panter
Robert Collins
Antoine Pitrou
R David Murray
Ezio Melotti
Benjamin Peterson
Florent Xicluna