If the nl_langinfo(CODESET) function returns an empty string, Python
now uses UTF-8 as the filesystem encoding.
In May 2010 (commit b744ba1d14), I
modified Python to log a warning and use UTF-8 as the filesystem
encoding (instead of None) if nl_langinfo(CODESET) returns an empty
string.
In August 2020 (commit 94908bbc15), I
modified Python startup to fail with a fatal error and a specific
error message if nl_langinfo(CODESET) returns an empty string. The
intent was to prevent guessing the encoding and also investigate user
configuration where this case happens.
In 10 years (2010 to 2020), I saw zero user report about the error
message related to nl_langinfo(CODESET) returning an empty string.
Today, UTF-8 became the defacto standard and it's safe to make the
assumption that the user expects UTF-8. For example,
nl_langinfo(CODESET) can return an empty string on macOS if the
LC_CTYPE locale is not supported, and UTF-8 is the default encoding
on macOS.
While this change is likely to not affect anyone in practice, it
should make UTF-8 lover happy ;-)
Rewrite also the documentation explaining how Python selects the
filesystem encoding and error handler.
No backport is required since union is only in 3.10.
This addresses "3. Consistency nitpicks for Union's docs" in the bpo.
Please skip news. Thank you.
Follow up to 7cdf30fff3 and 4173320920. This addresses the point "1. Update links in typing, subscription and union to point to GenericAlias." in the bpo for this PR.
Removed the unicodedata.ucnhash_CAPI attribute which was an internal
PyCapsule object. The related private _PyUnicode_Name_CAPI structure
was moved to the internal C API.
Rename unicodedata.ucnhash_CAPI as unicodedata._ucnhash_CAPI.
I am re-submitting an older PR which was abandoned but is still relevant, #10783 by @timb07.
The issue being solved () is still relevant. The original PR #10783 was closed as
the final request changes were not applied and since abandoned.
In this new PR I have re-used the original patch plus applied both comments from the review, by @maxking and @pganssle.
For reference, here is the original PR description:
In email.utils.parsedate_to_datetime(), a failure to parse the date, or invalid date components (such as hour outside 0..23) raises an exception. Document this behaviour, and add tests to test_email/test_utils.py to confirm this behaviour.
In email.headerregistry.DateHeader.parse(), check when parsedate_to_datetime() raises an exception and add a new defect InvalidDateDefect; preserve the invalid value as the string value of the header, but set the datetime attribute to None.
Add tests to test_email/test_headerregistry.py to confirm this behaviour; also added test to test_email/test_inversion.py to confirm emails with such defective date headers round trip successfully.
This pull request incorporates feedback gratefully received from @bitdancer, @brettcannon, @Mariatta and @warsaw, and replaces the earlier PR #2254.
Automerge-Triggered-By: GH:warsaw
* UCD_Check() uses PyModule_Check()
* Simplify the internal _PyUnicode_Name_CAPI structure:
* Remove size and state members
* Remove state and self parameters of getcode() and getname()
functions
* Remove global_module_state
The private _PyUnicode_Name_CAPI structure of the PyCapsule API
unicodedata.ucnhash_CAPI moves to the internal C API. Moreover, the
structure gets a new state member which must be passed to the
getcode() and getname() functions.
* Move Include/ucnhash.h to Include/internal/pycore_ucnhash.h
* unicodedata module is now built with Py_BUILD_CORE_MODULE.
* unicodedata: move hashAPI variable into unicodedata_module_state.
Add documentation to help diagnose CDLL dependent DLL loading errors
on windows for OSError with message:
"[WinError 126] The specified module could not be found"
This error is otherwise difficult to diagnose.
@ericsnowcurrently This PR will change the following:
In the library documentation importlib.rst:
- `module.__package__` can be `module.__name__` for packages;
- `spec.parent` can be `spec.__name__` for packages;
- `spec.loader` is not `None` for namespaces packages.
In the language documentation import.rst:
- `spec.loader` is not `None` for namespace packages.
Automerge-Triggered-By: GH:warsaw
This is a trivial fix to [bpo-39416](), which didn't come up until it was already committed
```
Change "Numeric" to "numeric".
I believe this is trivial enough to not need an issue or a NEWS entry, although
I'm unclear on what branches the original pull request received backports.
```
Automerge-Triggered-By: GH:merwok
[bpo-39416](): Document string representations of the Numeric classes
This is a change to the specification of the Python language.
The idea here is to put sane minimal limits on the Python language's default
representations of its Numeric classes. That way "Marty's Robotic Massage Parlor
and Python Interpreter" implementation of Python won't do anything too
crazy.
Some discussion in the email thread:
Subject: Documenting Python's float.__str__()
https://mail.python.org/archives/list/python-dev@python.org/thread/FV22TKT3S2Q3P7PNN6MCXI6IX3HRRNAL/
* Add _newline_ parameter to `pathlib.Path.write_text()`
* Update documentation of `pathlib.Path.write_text()`
* Add test case for `pathlib.Path.write_text()` calls with _newline_ parameter passed
Automerge-Triggered-By: GH:methane
Clarify in the subprocess documentation how searching for the executable to run works, noting that ``sys.executable`` is the recommended way to find the current interpreter.
* Add F_SETPIPE_SZ and F_GETPIPE_SZ to fcntl module
* Add pipesize parameter for subprocess.Popen class
This will allow the user to control the size of the pipes.
On linux the default is 64K. When a pipe is full it blocks for writing.
When a pipe is empty it blocks for reading. On processes that are
very fast this can lead to a lot of wasted CPU cycles. On a typical
Linux system the max pipe size is 1024K which is much better.
For high performance-oriented libraries such as xopen it is nice to
be able to set the pipe size.
The workaround without this feature is to use my_popen_process.stdout.fileno() in
conjuction with fcntl and 1031 (value of F_SETPIPE_SZ) to acquire this behavior.
Remove complex special methods __int__, __float__, __floordiv__,
__mod__, __divmod__, __rfloordiv__, __rmod__ and __rdivmod__
which always raised a TypeError.
`site.getusersitepackages()` returns the location of the user-specific site-packages directory
even when the user-specific site-packages is disabled.
```
$ python -s -m site
sys.path = [
'/home/user/conda/lib/python37.zip',
'/home/user/conda/lib/python3.7',
'/home/user/conda/lib/python3.7/lib-dynload',
'/home/user/conda/lib/python3.7/site-packages',
]
USER_BASE: '/home/user/.local' (exists)
USER_SITE: '/home/user/.local/lib/python3.7/site-packages' (doesn't exist)
ENABLE_USER_SITE: False
```
It was not practical to prevent the function from returning None if user-specific site-packages are disabled, since there are other uses of the function which are relying on this behaviour (e.g. `python -m site`).
This special marker annotation is intended to help in distinguishing
proper PEP 484-compliant type aliases from regular top-level variable
assignments.
The hard part was making all the tests pass; there are some subtle issues here, because apparently the future import wasn't tested very thoroughly in previous Python versions.
For example, `inspect.signature()` returned type objects normally (except for forward references), but strings with the future import. We changed it to try and return type objects by calling `typing.get_type_hints()`, but fall back on returning strings if that function fails (which it may do if there are future references in the annotations that require passing in a specific namespace to resolve).