The registry() method of functools.singledispatch() functions checks now
the first argument or the first parameter annotation and raises a TypeError if it is
not supported. Previously unsupported "types" were ignored (e.g. typing.List[int])
or caused an error at calling time (e.g. list[int]).
In order to fix a bug in the 3.9 branch in #29394, more tests were added to
``test_functools.py`` to ensure that ``singledispatchmethod`` still correctly
wrapped a target method, even if the target method had already been wrapped by
multiple other decorators. This PR brings the new tests into the 3.11 and 3.10
branches as well.
In Python 3.8 and 3.9, stacking `@functools.singledispatchmethod` on top of
`@classmethod` or `@staticmethod` caused an exception to be raised if the
method was registered using type-annotations rather than
`@method.register(int)`. This was not caught by unit tests, however, as the
tests only tested the `@method.register(int)` way of registering additional
implementations. The bug is no longer present in Python 3.10+, but
`test_functools.py` is still lacking regression tests for these cases. This
commit adds these test cases.
The hard part was making all the tests pass; there are some subtle issues here, because apparently the future import wasn't tested very thoroughly in previous Python versions.
For example, `inspect.signature()` returned type objects normally (except for forward references), but strings with the future import. We changed it to try and return type objects by calling `typing.get_type_hints()`, but fall back on returning strings if that function fails (which it may do if there are future references in the annotations that require passing in a specific namespace to resolve).
The topological sort functionality that was introduced initially in the
functools module has been moved to a new graphlib module to
better accommodate the new tools and keep the original scope of the
functools module.
This commit contains the implementation of PEP570: Python positional-only parameters.
* Update Grammar/Grammar with new typedarglist and varargslist
* Regenerate grammar files
* Update and regenerate AST related files
* Update code object
* Update marshal.c
* Update compiler and symtable
* Regenerate importlib files
* Update callable objects
* Implement positional-only args logic in ceval.c
* Regenerate frozen data
* Update standard library to account for positional-only args
* Add test file for positional-only args
* Update other test files to account for positional-only args
* Add News entry
* Update inspect module and related tests
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.