Typically, the second positional argument for ``seek()`` is *whence*. That is the POSIX standard name (http://man7.org/linux/man-pages/man3/lseek.3p.html) and the name listed in the documentation for ``io`` module (https://docs.python.org/3/library/io.html#io.IOBase.seek).
The tutorial for IO is the only location where the second positional argument for ``seek()`` is referred to as *from_what*. I suspect this was created at an early point in Python's history, and was never updated (as this section predates the GitHub repository):
```
$ git grep "from_what"
Doc/tutorial/inputoutput.rst:To change the file object's position, use ``f.seek(offset, from_what)``. The position is computed
Doc/tutorial/inputoutput.rst:the *from_what* argument. A *from_what* value of 0 measures from the beginning
Doc/tutorial/inputoutput.rst:the reference point. *from_what* can be omitted and defaults to 0, using the
```
For consistency, I am suggesting that the tutorial be updated to use the same argument name as the IO documentation and POSIX standard for ``seek()``, particularly since this is the only location where *from_what* is being used.
Note: In the POSIX standard, *whence* is technically the third positional argument, but the first argument *fildes* (file descriptor) is implicit in Python.
https://bugs.python.org/issue37635
* This just copies the docs from `StreamWriter` and `StreamReader`.
* Add docstring for asyncio functions.
https://bugs.python.org/issue36889
Automerge-Triggered-By: @asvetlov
The usedforsecurity keyword only argument added to the hash constructors is useful for FIPS builds and similar restrictive environment with non-technical requirements that legacy algorithms be forbidden by their implementations without being explicitly annotated as not being used for any security related purposes. Linux distros with FIPS support benefit from this being standard rather than making up their own way(s) to do it.
Contributed and Signed-off-by: Christian Heimes christian@python.org
* subprocess: Add user, group and extra_groups paremeters to subprocess.Popen
This adds a `user` parameter to the Popen constructor that will call
setreuid() in the child before calling exec(). This allows processes
running as root to safely drop privileges before running the subprocess
without having to use a preexec_fn.
This also adds a `group` parameter that will call setregid() in
the child process before calling exec().
Finally an `extra_groups` parameter was added that will call
setgroups() to set the supplimental groups.
* Add a note to the PyModule_AddObject docs.
* Correct example usages of PyModule_AddObject.
* Whitespace.
* Clean up wording.
* 📜🤖 Added by blurb_it.
* First code review.
* Add < 0 in the tests with PyModule_AddObject
* bpo-13927: time.ctime and time.asctime return string explantion
* Add note explaining that time.ctime and time.asctime returns a space padded date value in case it contains a single digit date
* Reformat linebreaks
The socket module now has the socket.send_fds() and socket.recv.fds() functions.
Contributed by Joannah Nanjekye, Shinya Okano (original patch)
and Victor Stinner.
Co-Authored-By: Victor Stinner <vstinner@redhat.com>
* bpo-36260: Add pitfalls to zipfile module documentation
We saw vulnerability warning description (including zip bomb) in Doc/library/xml.rst file.
This gave us the idea of documentation improvement.
So, we moved a little bit forward :P
And the doc patch can be found (pr).
* fix trailing whitespace
* 📜🤖 Added by blurb_it.
* Reformat text for consistency.
* bpo-35168: Documentation about shlex.punctuation_chars now states that it should be set in __init__.py
* bpo-35168: Convert shlex.punctuation_chars to read-only property
* Add NEWS.d entry
* Document `unittest.IsolatedAsyncioTestCase` API
* Add a simple example with respect to order of evaluation of setup and teardown calls.
https://bugs.python.org/issue32972
Automerge-Triggered-By: @asvetlov
This is a restructuring of the datetime documentation to hopefully make
them more user-friendly and approachable to new users without losing any
of the detail.
Changes include:
- Creating dedicated subsections for some concepts such as:
- "Constants"
- "Naive vs Aware"
- "Determining if an Object is Aware"
- Give 'naive vs aware' its own subsection
- Give 'constants' their own subsection
- Overhauling the strftime-strptime section by:
- Breaking it into logical, linkable, and digestable parts
- Adding a high-level comparison table
- Moving the technical detail to bottom: readers come to this
section primarily to remind themselves to things:
- How do I write the format code for X?
- strptime/strftime: which one is which again?
- Touching up fromisoformat + isoformat sections by:
- Revising fromisoformat + isoformat for date, time, and
datetime
- Adding basic examples
- Enforcing consistency about putting formats (i.e. ``HH:MM``)
in double backticks. This was previously done in some places
but not all
- Putting long 'supported formats', on their own line to improve
readability
- Moving the 'seealso' section to the top and add a link to dateutil
Rationale: This doesn't really belong nested under the
'constants' section. Let readers know right away that
datetime is one of several related tools.
- Moving common features of several types into one place:
Previously, each type went out of its way to note separately
that it was hashable and picklable. These can be brought
into one single place that is more prominent.
- Reducing some verbose explanations to improve readability
- Breaking up long paragraphs into digestable chunks
- Displaying longer "equivalent to" examples, as short code blocks
- Using the dot notation for datetime/time classes:
Use :class:`.time` and :class:`.datetime` rather than :class:`time` and
:class:`datetime`; otherwise, the generated links will route to the
respective modules, not classes.
- Rewording the tzinfo class description
The top paragraph should get straight to the point of telling the reader
what subclasses of tzinfo _do_. Previously, that was hidden in a later
paragraph.
- Adding a note on .today() versus .now()
- Rearranging and expanding example blocks, including:
- Moved long, multiline inline examples to standalone examples
- Simplified the example block for timedelta arithmetic:
- Broke the example into two logical sections:
1. normalization/parameter 'merging'
2. timedelta arithmetic
- Reduced the complexity of the some of the examples. Show
reasonable, real-world uses cases that are easy to follow
along with and progres in difficult slightly.
- Broke up the example sections for date and datetime sections by putting
the easy examples first, progressing to more esoteric situations and
breaking it up into logical sections based on what the methods are
doing at a high level.
- Simplified the KabulTz example:
- Put the class definition itself into a non-REPL block since there is
no interactive output involved there
- Briefly explained what's happening before launching into the code
- Broke the example section into visually separate chunks
- Various whitespace, formatting, style and grammar fixes including:
- Consistently using backctics for 'date_string' formats
- Consistently using one space after periods.
- Consistently using bold for vocab terms
- Consistently using italics when referring to params:
See https://devguide.python.org/documenting/#id4
- Using '::' to lead into code blocks
Per https://devguide.python.org/documenting/#source-code, this will
let the reader use the 'expand/collapse' top-right button for REPL
blocks to hide or show the prompt.
- Using consistent captialization schemes
- Removing use of the default role
- Put 'example' blocks in Markdown subsections
This is a combination of 66 commits.
See bpo-36960: https://bugs.python.org/issue36960
This PR deprecate explicit loop parameters in all public asyncio APIs
This issues is split to be easier to review.
fourth step: queue.py
https://bugs.python.org/issue36373
This PR deprecate explicit loop parameters in all public asyncio APIs
This issues is split to be easier to review.
Third step: locks.py
https://bugs.python.org/issue36373
* bpo-351428: Updates documentation to reflect AsyncMock call_count after await.
* Adds skip and fixes warning.
* Removes extra >>>.
* Adds ... in front of await mock().
The link we have points to the version from Unicode 6.0.0, dated 2010.
There have been numerous updates to it since then:
https://www.unicode.org/reports/tr44/#Modifications
Change the link to one that points to the current version. Also, use HTTPS.
* Minor changes.
* Update Doc/faq/library.rst
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>
* Apply suggestions from aeros167.
* Update Doc/faq/library.rst
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>
* Apply suggestions from aeros167 + re-add a "a" that was accidentally deleted.
* Update documentation for plistlib
- Update "Mac OS X" to "Apple" since plists are used more widely than just macOS
- Re-add the UID class documentation (oops, removed in GH-15615)
* Rename PyThreadState_DeleteCurrent()
to _PyThreadState_DeleteCurrent()
* Move it to the internal C API
Co-Authored-By: Carol Willing <carolcode@willingconsulting.com>
The purpose of the `unicodedata.is_normalized` function is to answer
the question `str == unicodedata.normalized(form, str)` more
efficiently than writing just that, by using the "quick check"
optimization described in the Unicode standard in UAX #15.
However, it turns out the code doesn't implement the full algorithm
from the standard, and as a result we often miss the optimization and
end up having to compute the whole normalized string after all.
Implement the standard's algorithm. This greatly speeds up
`unicodedata.is_normalized` in many cases where our partial variant
of quick-check had been returning MAYBE and the standard algorithm
returns NO.
At a quick test on my desktop, the existing code takes about 4.4 ms/MB
(so 4.4 ns per byte) when the partial quick-check returns MAYBE and it
has to do the slow normalize-and-compare:
$ build.base/python -m timeit -s 'import unicodedata; s = "\uf900"*500000' \
-- 'unicodedata.is_normalized("NFD", s)'
50 loops, best of 5: 4.39 msec per loop
With this patch, it gets the answer instantly (58 ns) on the same 1 MB
string:
$ build.dev/python -m timeit -s 'import unicodedata; s = "\uf900"*500000' \
-- 'unicodedata.is_normalized("NFD", s)'
5000000 loops, best of 5: 58.2 nsec per loop
This restores a small optimization that the original version of this
code had for the `unicodedata.normalize` use case.
With this, that case is actually faster than in master!
$ build.base/python -m timeit -s 'import unicodedata; s = "\u0338"*500000' \
-- 'unicodedata.normalize("NFD", s)'
500 loops, best of 5: 561 usec per loop
$ build.dev/python -m timeit -s 'import unicodedata; s = "\u0338"*500000' \
-- 'unicodedata.normalize("NFD", s)'
500 loops, best of 5: 512 usec per loop
Adds a link to `dateutil.parser.isoparse` in the documentation.
It would be nice to set up intersphinx for things like this, but I think we can leave that for a separate PR.
CC: @pitrou
[bpo-37979](https://bugs.python.org/issue37979)
https://bugs.python.org/issue37979
Automerge-Triggered-By: @pitrou
- drop TargetScopeError in favour of raising SyntaxError directly
as per the updated PEP 572
- comprehension iteration variables are explicitly local, but
named expression targets in comprehensions are nonlocal or
global. Raise SyntaxError as specified in PEP 572
- named expression targets in the outermost iterable of a
comprehension have an ambiguous target scope. Avoid resolving
that question now by raising SyntaxError. PEP 572
originally required this only for cases where the bound name
conflicts with the iteration variable in the comprehension,
but CPython can't easily restrict the exception to that case
(as it doesn't know the target variable names when visiting
the outermost iterator expression)
"Arguments may be integers... " could be misunderstand as they also
could be strings.
New wording makes it clear that arguments have to be integers.
modified: Doc/library/datetime.rst
Automerge-Triggered-By: @pganssle
Fix typo in description of link to mozilla bug report writing guidelines.
Though the URL is misleading, we're indeed trying to write bug _reports_, not to add bugs.
Automerge-Triggered-By: @ned-deily
The activation scripts generated by venv were inconsistent in how they changed the shell's prompt. Some used `__VENV_PROMPT__` exclusively, some used `__VENV_PROMPT__` if it was set even though by default `__VENV_PROMPT__` is always set and the fallback matched the default, and one ignored `__VENV_PROMPT__` and used `__VENV_NAME__` instead (and even used a differing format to the default prompt). This change now has all activation scripts use `__VENV_PROMPT__` only and relies on the fact that venv sets that value by default.
The color of the customization is also now set in fish to the blue from the Python logo for as hex color support is built into that shell (much like PowerShell where the built-in green color is used).
bpo-37834: Normalise handling of reparse points on Windows
* ntpath.realpath() and nt.stat() will traverse all supported reparse points (previously was mixed)
* nt.lstat() will let the OS traverse reparse points that are not name surrogates (previously would not traverse any reparse point)
* nt.[l]stat() will only set S_IFLNK for symlinks (previous behaviour)
* nt.readlink() will read destinations for symlinks and junction points only
bpo-1311: os.path.exists('nul') now returns True on Windows
* nt.stat('nul').st_mode is now S_IFCHR (previously was an error)
Added back mention that ensure_future actually scheduled obj. This documentation just mentions what ensure_future returns, so I did not realize that ensure_future also schedules obj.
There are plenty of legitimate scripts in the tree that begin with a
`#!`, but also a few that seem to be marked executable by mistake.
Found them with this command -- it gets executable files known to Git,
filters to the ones that don't start with a `#!`, and then unmarks
them as executable:
$ git ls-files --stage \
| perl -lane 'print $F[3] if (!/^100644/)' \
| while read f; do
head -c2 "$f" | grep -qxF '#!' \
|| chmod a-x "$f"; \
done
Looking at the list by hand confirms that we didn't sweep up any
files that should have the executable bit after all. In particular
* The `.psd` files are images from Photoshop.
* The `.bat` files sure look like things that can be run.
But we have lots of other `.bat` files, and they don't have
this bit set, so it must not be needed for them.
Automerge-Triggered-By: @benjaminp
The fact that keyword names are strings is now part of the vectorcall and `METH_FASTCALL` protocols. The biggest concrete change is that `_PyStack_UnpackDict` now checks that and raises `TypeError` if not.
CC @markshannon @vstinner
https://bugs.python.org/issue37540
The documented definition was much broader than the real one:
there are tons of characters with general category "Other",
and we don't (and shouldn't) treat most of them as whitespace.
Rewrite the definition to agree with the comment on
_PyUnicode_IsWhitespace, and with the logic in makeunicodedata.py,
which is what generates that function and so ultimately governs.
Add suitable breadcrumbs so that a reader who wants to pin down
exactly what this definition means (what's a "bidirectional class"
of "B"?) can do so. The `unicodedata` module documentation is an
appropriate central place for our references to Unicode's own copious
documentation, so point there.
Also add to the isspace() test a thorough check that the
implementation agrees with the intended definition.
* bpo-37256: Wording in Request class docs
* 📜🤖 Added by blurb_it.
* Update Misc/NEWS.d/next/Documentation/2019-07-16-14-48-12.bpo-37256.qJTrBb.rst
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>
https://bugs.python.org/issue37814:
> The empty tuple syntax in type annotations, `Tuple[()]`, is not obvious from the examples given in the documentation (I naively expected `Tuple[]` to work); it has been documented in PEP 484 and in mypy, but not in the documentation for the typing module.
https://bugs.python.org/issue37814
DeprecationWarning will continue to be emitted for invalid escape
sequences in string and bytes literals just as it did in 3.7.
SyntaxWarning may be emitted in the future. But per mailing list
discussion, we don't yet know when because we haven't settled on how to
do so in a non-disruptive manner.
(Applies 4c5b6bac24 to the master branch).
(This is https://github.com/python/cpython/pull/15142 for master/3.9)
https://bugs.python.org/issue32912
Automerge-Triggered-By: @gpshead
There was a discrepancy between the Python and C implementations.
Add singletons ALWAYS_EQ, LARGEST and SMALLEST in test.support
to test mixed type comparison.
Imports now raise `TypeError` instead of `ValueError` for relative import failures. This makes things consistent between `builtins.__import__` and `importlib.__import__` as well as using a more natural import for the failure.
https://bugs.python.org/issue37444
Automerge-Triggered-By: @brettcannon
Expose the CAN_BCM SocketCAN constants used in the bcm_msg_head struct
flags (provided by <linux/can/bcm.h>) under the socket library.
This adds the following constants with a CAN_BCM prefix:
* SETTIMER
* STARTTIMER
* TX_COUNTEVT
* TX_ANNOUNCE
* TX_CP_CAN_ID
* RX_FILTER_ID
* RX_CHECK_DLC
* RX_NO_AUTOTIMER
* RX_ANNOUNCE_RESUME
* TX_RESET_MULTI_IDX
* RX_RTR_FRAME
* CAN_FD_FRAME
The CAN_FD_FRAME flag was introduced in the 4.8 kernel, while the other
ones were present since SocketCAN drivers were mainlined in 2.6.25. As
such, it is probably unnecessary to guard against these constants being
missing.
Deprecate the parser module and add a deprecation warning triggered on import and a warning block in the documentation.
https://bugs.python.org/issue37268
Automerge-Triggered-By: @pablogsal
Prior to this change the guard on an 'elif' used an assignment expression whose value was used in a later 'else' block, causing some confusion for people.
(Discussion on Twitter: https://twitter.com/brettsky/status/1153861041068994566.)
Automerge-Triggered-By: @brettcannon
* Fix the formatting in the documentation of the tostring() functions.
* bpo-34160: Document that the tostring() and tostringlist() functions also preserve the attribute order now.
* bpo-34160: Add an explanation of how users should deal with the attribute order.
* Remove a vague statement in documentation
* Remove another vague sentence
A sentence starting with "So it should be possible..." shouldn't be in the docs either.
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>
* Include the removal of the previous line
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>
* Remove an extra space
The `allow_abbrev` option for ArgumentParser is documented and intended to disable support for unique prefixes of --options, which may sometimes be ambiguous due to deferred parsing.
However, the initial implementation also broke parsing of grouped short flags, such as `-ab` meaning `-a -b` (or `-a=b`). Checking the argument for a leading `--` before rejecting it fixes this.
This was prompted by pytest-dev/pytest#5469, so a backport to at least 3.8 would be great 😄
And this is my first PR to CPython, so please let me know if I've missed anything!
https://bugs.python.org/issue26967
Hi,
I've faced an issue w/ `mailbox.Maildir()`. The case is following:
1. I create a folder with `tempfile.TemporaryDirectory()`, so it's empty
2. I pass that folder path as an argument when instantiating `mailbox.Maildir()`
3. Then I receive an exception happening because "there's no such file or directory" (namely `cur`, `tmp` or `new`) during interaction with Maildir
**Expected result:** subdirs are created during `Maildir()` instance creation.
**Actual result:** subdirs are assumed as existing which leads to exceptions during use.
**Workaround:** remove the actual dir before passing the path to `Maildir()`. It will be created automatically with all subdirs needed.
**Fix:** This PR. Basically it adds creation of subdirs regardless of whether the base dir existed before.
https://bugs.python.org/issue30088
Fix importlib examples to insert any newly created modules via importlib.util.module_from_spec() immediately into sys.modules instead of after calling loader.exec_module().
Thanks to Benjamin Mintz for finding the bug.
https://bugs.python.org/issue37521
This is done to compensate for the extra stack frames added by
IDLE itself, which cause problems when setting the recursion limit
to low values.
This wraps sys.setrecursionlimit() and sys.getrecursionlimit()
as invisibly as possible.