* bpo-27578: Fix inspect.getsource() on empty file
For modules from empty files, `inspect.getsource()` now
returns an empty string, and `inspect.getsourcelines()` returns
a list of one empty string, fixing the expected invariant.
As indicated by `exec('')`, empty strings are valid Python
source code.
Co-authored-by: Oleg Iarygin <oleg@arhadthedev.net>
* GH-65056: Improve the IP address' is_global/is_private documentation
It wasn't clear what the semantics of is_global/is_private are and, when
one gets to the bottom of it, it's not quite so simple (hence the
exceptions listed).
Co-authored-by: Petr Viktorin <encukou@gmail.com>
In Lexical Analysis f-strings section, NULL in the description
of 'literal character' means '\0'. In the format_spec grammar
production, it is wrong with that meaning and redundant if
instead interpreted as <nothing>. Remove it there.
Even though it has no internal references to Python objects it still
has a reference to its type by virtue of being a heap type. We need
to provide a traverse function that visits the type, but we do not
need to provide a clear function.
Stop raising `ValueError` from `glob.translate()` when a `**` sub-string
appears in a non-recursive pattern segment. This matches `glob.glob()`
behaviour.
* Update titles and subtitles on landing page template
* address review from gvanrossum
* Edits from hugovk review
* Change word order back. Down the road we should split license and history
There is a race between when `Thread._tstate_lock` is released[^1] in `Thread._wait_for_tstate_lock()`
and when `Thread._stop()` asserts[^2] that it is unlocked. Consider the following execution
involving threads A, B, and C:
1. A starts.
2. B joins A, blocking on its `_tstate_lock`.
3. C joins A, blocking on its `_tstate_lock`.
4. A finishes and releases its `_tstate_lock`.
5. B acquires A's `_tstate_lock` in `_wait_for_tstate_lock()`, releases it, but is swapped
out before calling `_stop()`.
6. C is scheduled, acquires A's `_tstate_lock` in `_wait_for_tstate_lock()` but is swapped
out before releasing it.
7. B is scheduled, calls `_stop()`, which asserts that A's `_tstate_lock` is not held.
However, C holds it, so the assertion fails.
The race can be reproduced[^3] by inserting sleeps at the appropriate points in
the threading code. To do so, run the `repro_join_race.py` from the linked repo.
There are two main parts to this PR:
1. `_tstate_lock` is replaced with an event that is attached to `PyThreadState`.
The event is set by the runtime prior to the thread being cleared (in the same
place that `_tstate_lock` was released). `Thread.join()` blocks waiting for the
event to be set.
2. `_PyInterpreterState_WaitForThreads()` provides the ability to wait for all
non-daemon threads to exit. To do so, an `is_daemon` predicate was added to
`PyThreadState`. This field is set each time a thread is created. `threading._shutdown()`
now calls into `_PyInterpreterState_WaitForThreads()` instead of waiting on
`_tstate_lock`s.
[^1]: 441affc9e7/Lib/threading.py (L1201)
[^2]: 441affc9e7/Lib/threading.py (L1115)
[^3]: 8194653279
---------
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Antoine Pitrou <antoine@python.org>
Change automatically generated tkinter.Checkbutton widget names to
avoid collisions with automatically generated tkinter.ttk.Checkbutton
widget names within the same parent widget.
* Restore support of None and other false values.
* Raise TypeError for non-zero integers and non-empty sequences.
The regressions were introduced in gh-74668
(bdba8ef42b).
Any capitalization of "xn--" should be acceptable for the ACE prefix
(see https://tools.ietf.org/html/rfc3490#section-5).
Co-authored-by: Pepijn de Vos <pepijndevos@gmail.com>
Co-authored-by: Erlend E. Aasland <erlend@python.org>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Since 3.12, allocating a GC object cannot immediately trigger GC. This
allows us to simplify the logic for creating the canonical callback-less
weakref.
Use the NtQueryInformationProcess system call to efficiently retrieve the parent process ID in a single step, rather than using the process snapshots API which retrieves large amounts of unnecessary information and is more prone to failure (since it makes heap allocations).
Includes a fallback to the original win32_getppid implementation in case the unstable API appears to return strange results.
kernc
Victor Stinner
Jakub Stasiak
Erlend E. Aasland
AN Long
Terry Jan Reedy
Hugo van Kemenade
mpage
Barney Gale
Antoine Pitrou
John Sloboda
Carol Willing
Michael Droettboom
Donghee Na
jnchen
Serhiy Storchaka
Nikita Sobolev
Raymond Hettinger
Mark Shannon
Dino Viehland
Tian Gao
Zackery Spytz
vxiiduu
Jason R. Coombs