mpage [Wed, 8 May 2024 20:03:39 +0000 (13:03 -0700)]
gh-117657: Fix data races when writing / reading `ob_gc_bits` (#118292)
Use relaxed atomics when reading / writing to the field. There are still a
few places in the GC where we do not use atomics. Those should be safe as
the world is stopped.
Tim Peters [Wed, 8 May 2024 00:09:09 +0000 (19:09 -0500)]
gh-118610: Centralize power caching in `_pylong.py` (#118611)
A new `compute_powers()` function computes all and only the powers of the base the various base-conversion functions need, as efficiently as reasonably possible (turns out that invoking `**`is needed at most once). This typically gives a few % speedup, but the primary point is to simplify the base-conversion functions, which no longer need their own, ad hoc, and less efficient power-caching schemes.
T. Wouters [Tue, 7 May 2024 21:00:25 +0000 (23:00 +0200)]
gh-109975: Make a rough editorial pass over What's New (#118711)
Make a rough editorial pass over Python 3.13's What's New document. Add the
release highlights, remove or merge some duplicated entries, and reorder
some of the sections (removals should really go before future deprecations).
The `pool_in_threads.py` test file may crash in free-threaded builds,
which can lead to the Tsan test hanging. Skip it for now until we fix
the underlying issue.
gh-66410: Do not stringify arguments of Tkinter callback (GH-98592)
Callbacks registered in the tkinter module now take arguments as
various Python objects (int, float, bytes, tuple), not just str.
To restore the previous behavior set tkinter module global wantobject to 1
before creating the Tk object or call the wantobject() method of the Tk object
with argument 1.
Calling it with argument 2 restores the current default behavior.
gh-118310: Fix documentation for `enum.Enum.__new__` (GH-118311)
The provided example was incorrect:
- The example enum was missing the `int` mixin as implied by the context
- The value of `int('1a', 16)` was incorrectly given as 17
(should be 26)
argparse performs a complex formatting of the usage for argument grouping
and for line wrapping to fit the terminal width. This formatting has been
a constant source of bugs for at least 10 years (see linked issues below)
where defensive assertion errors are triggered or brackets and paranthesis
are not properly handeled.
Problem
=======
The current implementation of argparse usage formatting relies on regular
expressions to group arguments usage only to separate them again later
with another set of regular expressions. This is a complex and error prone
approach that caused all the issues linked below. Special casing certain
argument formats has not solved the problem. The following are some of
the most common issues:
- empty `metavar`
- mutually exclusive groups with `SUPPRESS`ed arguments
- metavars with whitespace
- metavars with brackets or paranthesis
Solution
========
The following two comments summarize the solution:
- https://github.com/python/cpython/issues/82091#issuecomment-1093832187
- https://github.com/python/cpython/issues/77048#issuecomment-1093776995
Mainly, the solution is to rewrite the usage formatting to avoid the
group-then-separate approach. Instead, the usage parts are kept separate
and only joined together at the end. This allows for a much simpler
implementation that is easier to understand and maintain. It avoids the
regular expressions approach and fixes the corresponding issues.
This closes the following GitHub issues:
- #62090
- #62549
- #77048
- #82091
- #89743
- #96310
- #98666
Eric Snow [Tue, 7 May 2024 04:21:51 +0000 (22:21 -0600)]
gh-117953: Always Run Extension Init Func in Main Interpreter First (gh-118157)
This change makes sure all extension/builtin modules have their init function run first by the main interpreter before proceeding with import in the original interpreter (main or otherwise). This means when the import of a single-phase init module fails in an isolated subinterpreter, it won't tie any global state/callbacks to the subinterpreter.
Brett Simmers [Tue, 7 May 2024 03:07:23 +0000 (20:07 -0700)]
gh-116322: Enable the GIL while loading C extension modules (#118560)
Add the ability to enable/disable the GIL at runtime, and use that in
the C module loading code.
We can't know before running a module init function if it supports
free-threading, so the GIL is temporarily enabled before doing so. If
the module declares support for running without the GIL, the GIL is
later disabled. Otherwise, the GIL is permanently enabled, and will
never be disabled again for the life of the current interpreter.
Sam Gross [Tue, 7 May 2024 00:12:39 +0000 (20:12 -0400)]
gh-118527: Intern code consts in free-threaded build (#118667)
We already intern and immortalize most string constants. In the
free-threaded build, other constants can be a source of reference count
contention because they are shared by all threads running the same code
objects.
Jelle Zijlstra [Mon, 6 May 2024 22:57:27 +0000 (15:57 -0700)]
gh-117486: Improve behavior for user-defined AST subclasses (#118212)
Now, such classes will no longer require changes in Python 3.13 in the normal case.
The test suite for robotframework passes with no DeprecationWarnings under this PR.
I also added a new DeprecationWarning for the case where `_field_types` exists
but is incomplete, since that seems likely to indicate a user mistake.
Dino Viehland [Mon, 6 May 2024 17:50:35 +0000 (10:50 -0700)]
gh-118362: Fix thread safety around lookups from the type cache in the face of concurrent mutators (#118454)
Add _PyType_LookupRef and use incref before setting attribute on type
Makes setting an attribute on a class and signaling type modified atomic
Avoid adding re-entrancy exposing the type cache in an inconsistent state by decrefing after type is updated
gh-71592: Add ability to trace Tcl commands executed by Tkinter (GH-118291)
This is an experimental feature, for internal use.
Setting tkinter._debug = True before creating the root window enables
printing every executed Tcl command (or a Tcl command equivalent to the
used Tcl C API).
This will help to convert a Tkinter example into Tcl script to check
whether the issue is caused by Tkinter or exists in the underlying Tcl/Tk
library.
gh-118271: Support more options for reading/writing images in Tkinter (GH-118273)
* Add PhotoImage.read() to read an image from a file.
* Add PhotoImage.data() to get the image data.
* Add background and grayscale parameters to PhotoImage.write().
gh-118225: Support more options for copying images in Tkinter (GH-118228)
* Add the PhotoImage method copy_replace() to copy a region
from one image to other image, possibly with pixel zooming and/or
subsampling.
* Add from_coords parameter to PhotoImage methods copy(), zoom() and subsample().
* Add zoom and subsample parameters to PhotoImage method copy().