Alyssa Coghlan [Tue, 21 May 2024 03:32:15 +0000 (13:32 +1000)]
gh-74929: PEP 667 general docs update (gh-119201)
* expand on What's New entry for PEP 667 (including porting notes)
* define 'optimized scope' as a glossary term
* cover comprehensions and generator expressions in locals() docs
* review all mentions of "locals" in documentation (updating if needed)
* review all mentions of "f_locals" in documentation (updating if needed)
Victor Stinner [Mon, 20 May 2024 21:05:39 +0000 (17:05 -0400)]
gh-119050: Add XML support to libregrtest refleak checker (#119148)
regrtest test runner: Add XML support to the refleak checker
(-R option).
* run_unittest() now stores XML elements as string, rather than
objects, in support.junit_xml_list.
* runtest_refleak() now saves/restores XML strings before/after
checking for reference leaks. Save XML into a temporary file.
Toshio Kuratomi [Mon, 20 May 2024 19:10:47 +0000 (12:10 -0700)]
gh-92081: Fix for email.generator.Generator with whitespace between encoded words. (#92281)
* Fix for email.generator.Generator with whitespace between encoded words.
email.generator.Generator currently does not handle whitespace between
encoded words correctly when the encoded words span multiple lines. The
current generator will create an encoded word for each line. If the end
of the line happens to correspond with the end real word in the
plaintext, the generator will place an unencoded space at the start of
the subsequent lines to represent the whitespace between the plaintext
words.
A compliant decoder will strip all the whitespace from between two
encoded words which leads to missing spaces in the round-tripped
output.
The fix for this is to make sure that whitespace between two encoded
words ends up inside of one or the other of the encoded words. This
fix places the space inside of the second encoded word.
A second problem happens with continuation lines. A continuation line that
starts with whitespace and is followed by a non-encoded word is fine because
the newline between such continuation lines is defined as condensing to
a single space character. When the continuation line starts with whitespace
followed by an encoded word, however, the RFCs specify that the word is run
together with the encoded word on the previous line. This is because normal
words are filded on syntactic breaks by encoded words are not.
The solution to this is to add the whitespace to the start of the encoded word
on the continuation line.
Test cases are from #92081
* Rename a variable so it's not confused with the final variable.
Hood Chatham [Mon, 20 May 2024 17:42:15 +0000 (13:42 -0400)]
DOCS: Suggest always calling exec with a globals argument and no locals argument (GH-119235)
Many users think they want a locals argument for various reasons but they do not
understand that it makes code be treated as a class definition. They do not want
their code treated as a class definition and get surprised. The reason not
to pass locals specifically is that the following code raises a `NameError`:
```py
exec("""
def f():
print("hi")
f()
def g():
f()
g()
""", {}, {})
```
The reason not to leave out globals is as follows:
pulkin [Sun, 19 May 2024 21:46:37 +0000 (23:46 +0200)]
gh-119105: difflib: improve recursion for degenerate cases (#119131)
Code from https://github.com/pulkin, in PR
https://github.com/python/cpython/pull/119131
Greatly speeds `Differ` when there are many identically scoring pairs, by splitting the recursion near the inputs' midpoints instead of degenerating (as now) into just peeling off the first two lines.
Jelle Zijlstra [Sun, 19 May 2024 02:15:14 +0000 (22:15 -0400)]
marshal docs: Remove reference to "Sun" (#119161)
Nobody has been using a Sun machine for a long time. When I saw
this sentence in a lightning talk just now, I thought it was talking
about sending Python code on a spacecraft.
Tim Peters [Sun, 19 May 2024 01:54:23 +0000 (20:54 -0500)]
Try to repair oddball test bots timing out in test_int (#119166)
Various test bots (outside the ones GH normally runs) are timing out during test_int after ecd8664 (asymptotically faster str->int). Best guess is that they don't build the C _decimal module. So require that module in the most likely tests to time out then. Flying mostly blind, though!
Asymptotically faster (O(n log n)) str->int for very large strings, leveraging the faster multiplication scheme in the C-coded `_decimal` when available. This is used instead of the current Karatsuba-limited method starting at 2 million digits.
Lots of opportunity remains for fine-tuning. Good targets include changing BYTELIM, and possibly changing the internal output base (from 256 to a higher number of bytes).
Doing this was substantial work, and many of the new lines are actually comments giving correctness proofs. The obvious approaches sticking to integers were too slow to be useful, so this is doing variable-precision decimal floating-point arithmetic. Much faster, but worst-possible rounding errors have to be wholly accounted for, using as little precision as possible.
Special thanks to Serhiy Storchaka for asking many good questions in his code reviews!
Jelle Zijlstra [Wed, 15 May 2024 02:39:12 +0000 (22:39 -0400)]
3.13 What's New: Add PEP 702 (#118922)
I honestly forgot this slipped into 3.13, but I think it's worth highlighting more, as it is a PEP-sized change that makes the type system significantly more powerful.
@Yhg1s I think it's also worth mentioning in your release announcements.
Barney Gale [Tue, 14 May 2024 17:53:15 +0000 (18:53 +0100)]
GH-101357: Suppress `OSError` from `pathlib.Path.exists()` and `is_*()` (#118243)
Suppress all `OSError` exceptions from `pathlib.Path.exists()` and `is_*()`
rather than a selection of more common errors as we do presently. Also
adjust the implementations to call `os.path.exists()` etc, which are much
faster on Windows thanks to GH-101196.
Sam Gross [Fri, 10 May 2024 20:29:29 +0000 (16:29 -0400)]
gh-118846: Fix free-threading test failures when run sequentially (#118864)
The free-threaded build currently immortalizes some objects once the
first thread is started. This can lead to test failures depending on the
order in which tests are run. This PR addresses those failures by
suppressing immortalization or skipping the affected tests.
Victor Stinner [Fri, 10 May 2024 19:08:24 +0000 (21:08 +0200)]
gh-118702: Implement vectorcall for BaseException (#118703)
* BaseException_vectorcall() now creates a tuple from 'args' array.
* Creation an exception using BaseException_vectorcall() is now a
single function call, rather than having to call
BaseException_new() and then BaseException_init().
Calling BaseException_init() is inefficient since it overrides
the 'args' attribute.
* _PyErr_SetKeyError() now uses PyObject_CallOneArg() to create the
KeyError instance to use BaseException_vectorcall().
Jelle Zijlstra [Fri, 10 May 2024 16:55:49 +0000 (09:55 -0700)]
Rename typing._collect_parameters (#118900)
Unfortunately, released versions of typing_extensions
monkeypatch this function without the extra parameter, which makes
it so things break badly if current main is used with typing_extensions.
Fortunately, the monkeypatching is not needed on Python 3.13, because CPython
now implements PEP 696. By renaming the function, we prevent the monkeypatch
from breaking typing.py internals.
We keep the old name (raising a DeprecationWarning) to help other external users who call it.
Barney Gale [Fri, 10 May 2024 15:53:46 +0000 (16:53 +0100)]
GH-78707: Drop deprecated `pathlib.PurePath.[is_]relative_to()` arguments (#118780)
Remove support for supplying additional positional arguments to
`PurePath.relative_to()` and `is_relative_to()`. This has been deprecated
since Python 3.12.