argparse: Remove unused name variable when handling ArgumentTypeError (#96549)
This removes the unused `name` variable in the block where `ArgumentTypeError` is handled.
`ArgumentTypeError` errors are handled by showing just the string of the exception; unlike `ValueError`, the name (`__name__`) of the function is not included in the error message.
gh-92986: Fix ast.unparse when ImportFrom.level is None (#92992)
This doesn't happen naturally, but is allowed by the ASDL and compiler.
We don't want to change ASDL for backward compatibility reasons
(#57645, #92987)
Mark Dickinson [Sun, 4 Sep 2022 16:21:18 +0000 (17:21 +0100)]
gh-95778: Correctly pre-check for int-to-str conversion (#96537)
Converting a large enough `int` to a decimal string raises `ValueError` as expected. However, the raise comes _after_ the quadratic-time base-conversion algorithm has run to completion. For effective DOS prevention, we need some kind of check before entering the quadratic-time loop. Oops! =)
The quick fix: essentially we catch _most_ values that exceed the threshold up front. Those that slip through will still be on the small side (read: sufficiently fast), and will get caught by the existing check so that the limit remains exact.
The justification for the current check. The C code check is:
```c
max_str_digits / (3 * PyLong_SHIFT) <= (size_a - 11) / 10
```
In GitHub markdown math-speak, writing $M$ for `max_str_digits`, $L$ for `PyLong_SHIFT` and $s$ for `size_a`, that check is:
$$\left\lfloor\frac{M}{3L}\right\rfloor \le \left\lfloor\frac{s - 11}{10}\right\rfloor$$
From this it follows that
$$\frac{M}{3L} < \frac{s-1}{10}$$
hence that
$$\frac{L(s-1)}{M} > \frac{10}{3} > \log_2(10).$$
So
$$2^{L(s-1)} > 10^M.$$
But our input integer $a$ satisfies $|a| \ge 2^{L(s-1)}$, so $|a|$ is larger than $10^M$. This shows that we don't accidentally capture anything _below_ the intended limit in the check.
Charlie Zhao [Sun, 4 Sep 2022 10:37:04 +0000 (18:37 +0800)]
gh-93884: Improve test coverage of `PyNumber_ToBase` (GH-93932)
Link to #93884
* Test with some large negative and positive values(out of range of a longlong,i.e.[-2\*\*63, 2\*\*63-1])
* Test with objects of non-int type
bpo-30419: DOC: Update missing information in bdb docs (#1687)
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com> Co-authored-by: Martin Panter <vadmium@users.noreply.github.com> Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
gh-95778: CVE-2020-10735: Prevent DoS by very large int() (#96499)
Integer to and from text conversions via CPython's bignum `int` type is not safe against denial of service attacks due to malicious input. Very large input strings with hundred thousands of digits can consume several CPU seconds.
This PR comes fresh from a pile of work done in our private PSRT security response team repo.
Signed-off-by: Christian Heimes [Red Hat] <christian@python.org> Tons-of-polishing-up-by: Gregory P. Smith [Google] <greg@krypto.org>
Reviews via the private PSRT repo via many others (see the NEWS entry in the PR).
I wrote up [a one pager for the release managers](https://docs.google.com/document/d/1KjuF_aXlzPUxTK4BMgezGJ2Pn7uevfX7g0_mvgHlL7Y/edit#). Much of that text wound up in the Issue. Backports PRs already exist. See the issue for links.
gh-96143: Allow Linux perf profiler to see Python calls (GH-96123)
:warning: :warning: Note for reviewers, hackers and fellow systems/low-level/compiler engineers :warning: :warning:
If you have a lot of experience with this kind of shenanigans and want to improve the **first** version, **please make a PR against my branch** or **reach out by email** or **suggest code changes directly on GitHub**.
If you have any **refinements or optimizations** please, wait until the first version is merged before starting hacking or proposing those so we can keep this PR productive.
Christian Heimes [Tue, 30 Aug 2022 05:56:26 +0000 (07:56 +0200)]
gh-95853: Improve WASM build script (GH-96389)
- pre-build Emscripten ports and system libraries
- check for broken EMSDK versions
- use EMSDK's node for wasm32-emscripten
- warn when PKG_CONFIG_PATH is set
- add support level information
Victor Stinner [Mon, 29 Aug 2022 12:55:46 +0000 (14:55 +0200)]
Fix Py_INCREF() statistics in limited C API 3.10 (#96120)
In the limited C API with a debug build, Py_INCREF() is implemented
by calling _Py_IncRef() which calls Py_INCREF(). Only call
_Py_INCREF_STAT_INC() once.
Petr Viktorin [Mon, 29 Aug 2022 11:10:52 +0000 (13:10 +0200)]
gh-90814: Correct NEWS wording re. optional C11 features (GH-96309)
The previous wording of this entry suggests that CPython
won't work if optional compiler features are enabled.
That's not the case. The change is that we require C11 rather
than C89.
Note that PEP 7 does say "Python 3.11 and newer versions use C11
without optional features." It is correct there: that's
not a guide for users who compile Python, but for CPython devs
who must avoid the features.
TW [Sun, 28 Aug 2022 21:27:42 +0000 (23:27 +0200)]
gh-69142: add %:z strftime format code (gh-95983)
datetime.isoformat generates the tzoffset with colons, but there
was no format code to make strftime output the same format.
for simplicity and consistency the %:z formatting behaves mostly
as %z, with the exception of adding colons. this includes the
dynamic behaviour of adding seconds and microseconds only when
needed (when not 0).
this fixes the still open "generate" part of this issue:
Pankaj Pandey [Fri, 26 Aug 2022 14:20:48 +0000 (10:20 -0400)]
bpo-33587: inspect.getsource: reorder stat on file in linecache (GH-6805)
* inspect.getsource: avoid stat on file in linecache
The check for os.path.exists() on source file is postponed in
inspect.getsourcefile() until needed avoiding an expensive filesystem
stat call and PEP 302 module loader check is moved last for performance
since it is an uncommon case.