Ensure that APPENDS and SETITEMS are never used for a batch of size 1.
Ensure that ADDITEMS and SETITEMS are never used for a batch of size 0.
This harmonizes the C implementation with the Python implementation
which already guarantees this and makes a pickle a tiny bit smaller
with a tiny chance (about 0.1%).
Saves 1 byte for list and dict with size 1001, 2001, ...
Saves 2 bytes for set and dict with size 1000, 2000, ...
Since the code for rule NR2 is already here, to support CJK unified
ideographs and Tangut ideographs, it can also be used for other names
derived by rule NR2.
* Docs: a start on an 'improve this page' feature
* pr feedback: simplify the link, and don't scare people with the cla
* pr feedback answered
- use the actual page URL
- tighten the wording
* fix the improve link on the improve page
* news item
* Update Doc/improve-page.rst
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
* fix whitespace
* A nojs version of the page
* comments to help people keep the two pages in sync
* protect against XSS
* use template for issues from the nojs page
* use the template from the JS page as well
* give the docs issue template a fillable description field
* ugh, getting sloppy
* remove more sloppiness
---------
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
Align the QSBR thread state array to a 64-byte cache line boundary
and add padding at the end of _PyThreadStateImpl. Depending on heap
layout, the QSBR array could end up sharing a cache line with a
thread's tlbc_index, causing QSBR quiescent state updates to contend
with reads of tlbc_index in RESUME_CHECK. This is sensitive to
earlier allocations during interpreter init and can appear or
disappear with seemingly unrelated changes.
Either change alone is sufficient to fix the specific issue, but both
are worthwhile to avoid similar problems in the future.
Add TYPE_FROZENDICT to the marshal module.
Add C API functions:
* PyAnyDict_Check()
* PyAnyDict_CheckExact()
* PyFrozenDict_Check()
* PyFrozenDict_CheckExact()
* PyFrozenDict_New()
Add PyFrozenDict_Type C type.
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: Adam Johnson <me@adamj.eu>
Co-authored-by: Benedikt Johannes <benedikt.johannes.hofer@gmail.com>
The unparser was not handling the `is_lazy` attribute on Import and
ImportFrom AST nodes, causing lazy imports to be unparsed as regular
imports. This broke the round-trip (parse → unparse → reparse) for
any file containing `lazy import` statements.
* %D support for strptime, including test and Doc update
* additional %D test
* change documentation example date for %D so it is more legible to non-US readers
* change testing date for %D so it is more legible to non-US readers
* mv News blurb to Library, consistent with previous %F change
* change invalid format code from %D to C-standard unused %!
* Fix erroneous and misleading example Doc to %y from %Y, use correct C99+ definition for C99 %D; update additional tests
---------
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
In newPySSLSocket(), when SSL_new() returns NULL, Py_DECREF(self)
was called before _setSSLError(get_state_ctx(self), ...), causing
a use-after-free. Additionally, get_state_ctx() was called with
self (PySSLSocket*) instead of sslctx (PySSLContext*), which is
a type confusion bug.
Fix by calling _setSSLError() before Py_DECREF() and using
sslctx instead of self for get_state_ctx().
Adds `prefixmatch` APIs to the re module as an alternate name for our long existing `match` APIs to help alleviate a common Python confusion for those coming from other languages regular expression libraries.
These alleviate common confusion around what "match" means as Python is different than other popular languages regex libraries in our use of the term as an API name. The original `match` names are **NOT being deprecated**. Source tooling like linters, IDEs, and LLMs could suggest using `prefixmatch` instead of match to improve code health and reduce cognitive burden of understanding the intent of code when configured for a modern minimum Python version.
See the documentation changes for a better description.
Discussions took place in the PR, in the issue, and finally at https://discuss.python.org/t/add-re-prefixmatch-deprecate-re-match/105927
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: Shantanu <12621235+hauntsaninja@users.noreply.github.com>
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add a regression test ensuring that circular lazy imports raise a proper
error (ImportCycleError) instead of crashing with a segfault. The crash
was fixed in gh-144733 but no test was added at the time.
Guard against NULL pointer arithmetic in `_PyLexer_remember_fstring_buffers`
and `_PyLexer_restore_fstring_buffers`. When `start` or `multi_line_start`
are NULL (uninitialized in tok_mode_stack[0]), performing `NULL - tok->buf`
is undefined behavior. Add explicit NULL checks to store -1 as sentinel
and restore NULL accordingly.
Add test_lexer_buffer_realloc_with_null_start to test_repl.py that
exercises the code path where the lexer buffer is reallocated while
tok_mode_stack[0] has NULL start/multi_line_start pointers. This
triggers _PyLexer_remember_fstring_buffers and verifies the NULL
checks prevent undefined behavior.
To avoid duplicate content in the Enum HOWTO and
API documentation which is not automatically synced,
the section about supported __dunder__ and _sunder
names is moved from HOWTO to API docs.
See also https://github.com/python/cpython/pull/136791
