gh-132561: Fix the public multiprocessing.SemLock.locked method

[YvesDup]

Fix the public multiprocessing.SemLock.lockedmethod, add a docstring.
Add 2 tests for multiprocessing.Lock and multiprocessing.RLock.

• Issue: The new multiprocessing.[R]Lock.locked() method fails. #132561

[ZeroIntensity]

LGTM

[sobolevn]

CC @vstinner and @gpshead

Thanks again!

[vstinner]

Python 3.13 doesn't have the locked() method, it's a new feature in Python 3.14.

[vstinner]

LGTM

[vstinner]

Merged, thanks for the fix.

[YvesDup]

Sorry for my late awaken , but as the locked method is defined in the multiprocessing.SemLock base class, should not we modify documentation for multiprocessing.[Bounded]Semaphore classes by adding an entry for this public method ?

[vstinner]

If you consider that the doc is wrong, please go ahead and propose a doc change.

[chris-eibl]

If my analysis is correct, this has broken the AMD64 FreeBSD14 3.x and AMD64 FreeBSD15 3.x build bots, see #132719 (comment).

[sobolevn]

Thanks for the info! I will try to fix this ASAP :)

[YvesDup]

From https://buildbot.python.org/#/builders/1232/builds/5389/steps/6/logs/stdio

======================================================================
ERROR: test_rlock_locked_2processes (test.test_multiprocessing_fork.test_processes.WithProcessesTestLock.test_rlock_locked_2processes)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/buildbot/buildarea/3.x.opsec-fbsd14/build/Lib/test/_test_multiprocessing.py", line 1591, in test_rlock_locked_2processes
res = Value('b', 0)
^^^^^
NameError: name 'Value' is not defined. Did you mean: 'self.Value'?

See

cpython/Lib/test/_test_multiprocessing.py

Line 1591 in 71da68d

res=Value('b', 0)

The fix should be: res = self.Value('b', 0)

I don't figure out why tests failed for AMD64 FreeBSD14 3.x and succeeded on Ubuntu.

Edit: I will send a fix tomorrow

[sobolevn]

@YvesDup because of this line: from multiprocessing.sharedctypes import Value, copy
It is not always available :)

Please, send a PR.