Various date parsing utilities in the email module, such as
email.utils.parsedate(), are supposed to gracefully handle invalid
input, typically by raising an appropriate exception or by returning
None.
The internal email._parseaddr._parsedate_tz() helper used by some of
these date parsing routines tries to be robust against malformed input,
but unfortunately it can still crash ungracefully when a non-empty but
whitespace-only input is passed. This manifests as an unexpected
IndexError.
In practice, this can happen when parsing an email with only a newline
inside a ‘Date:’ header, which unfortunately happens occasionally in the
real world.
Here's a minimal example:
$ python
Python 3.9.6 (default, Jun 30 2021, 10:22:16)
[GCC 11.1.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import email.utils
>>> email.utils.parsedate('foo')
>>> email.utils.parsedate(' ')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python3.9/email/_parseaddr.py", line 176, in parsedate
t = parsedate_tz(data)
File "/usr/lib/python3.9/email/_parseaddr.py", line 50, in parsedate_tz
res = _parsedate_tz(data)
File "/usr/lib/python3.9/email/_parseaddr.py", line 72, in _parsedate_tz
if data[0].endswith(',') or data[0].lower() in _daynames:
IndexError: list index out of range
The fix is rather straight-forward: guard against empty lists, after
splitting on whitespace, but before accessing the first element.
* Fix typo in __repr__ code
* Add more tests for global int flag reprs
* use last module if multi-module string
- when an enum's `__module__` contains several module names, only
use the last one
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
Co-authored-by: Ethan Furman <ethan@stoneleaf.us>
* Use binascii.a2b_base64 to validate b64decode input.
This change leads to exception messages changes (mostly).
* Added more information to docstring of b64decode
* Added a reference to binascii.a2b_base64 in the docs
Method stopTestRun() is now always called in pair with method startTestRun()
for TestResult objects implicitly created in TestCase.run().
Previously it was not called for test methods and classes decorated with
a skipping decorator.
Additional improvements:
- messages which were compiled regular expressions aren't unpacked back into
strings for unmatched warnings;
- removed unnecessary "if tokens:" check (there's one before the for loop);
- took `endswith` calculation out of the for loop.
While the comment said 'We don't bother resizing localspluskinds',
this would cause .replace() to crash when it happened.
(Also types.CodeType(), but testing that is tedious, and this tests all
code paths.)
This is part of an investigation of a non-deterministic reference leak. While we're looking for the root cause, this is included temporarily so that CI doesn't fail on this particular issue. This enables it to find other regressions in the meantime, which would otherwise be shadowed by our known issue.
Implements a two steps check in `importlib._bootstrap._find_and_load()` to avoid locking when the module has been already imported and it's ready.
---
Using `importlib.__import__()`, after this, does show a big difference:
Before:
```
$ ./python -c 'import timeit; print(timeit.timeit("__import__(\"timeit\")", setup="from importlib import __import__"))'
15.92248619502061
```
After:
```
$ ./python -c 'import timeit; print(timeit.timeit("__import__(\"timeit\")", setup="from importlib import __import__"))'
1.206068897008663
```
---
On non-Linux POSIX platforms, like FreeBSD or macOS,
the FD used to read a forked PTY may signal its exit not
by raising an error but by sending empty data to the read
syscall. This case wasn't handled, leading to hanging
`pty.spawn` calls.
Co-authored-by: Reilly Tucker Siemens <reilly@tuckersiemens.com>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>