PR #4906 changed the typing.Generic class hierarchy, leaving an
outdated comment in the library reference. User-defined Generic ABCs now
must get a abc.ABCMeta metaclass from something other than typing.Generic
inheritance.
Prior to 3.7, re.escape escaped many characters that don't have
special meaning in Python, but that use to require escaping in other
tools and languages. This commit aims to make it clear which characters
were, but are no longer escaped.
The `required` argument to `argparse.add_subparsers` was added in #3027. This PR specifies the earliest version of Python where it is available.
https://bugs.python.org/issue26510
Automerge-Triggered-By: @merwok
Important work originally done by @emilyemorehouse two years ago and nearly ready to go in.
This bug has affected many people and in some cases has been a dealbreaker to the adoption of the otherwise wonderful pathlib and PEP519. https://stackoverflow.com/questions/33625931/copy-file-with-pathlib-in-python.
This adds the outstanding test request from that PR @vstinner (https://github.com/python/cpython/pull/5393).
Test fails without the change, passes with it, along with every other test in test_shutil.
Some variants were experimented with to make the one line change and the most performant one was picked.
# Added Test for PathLike directory destination, the current fail case
```
Lib/test/test_shutil.py::TestMove::test_move_file_pathlike FAILED [100%]
============================================================== FAILURES ===============================================================
__________________________________________________ TestMove.test_move_file_pathlike ___________________________________________________
self = <test.test_shutil.TestMove testMethod=test_move_file_pathlike>
def test_move_file_pathlike(self):
# Move a file to another location on the same filesystem.
src = pathlib.Path(self.src_file)
> self._check_move_file(src, self.dst_dir, self.dst_file)
Lib/test/test_shutil.py:1563:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Lib/test/test_shutil.py:1545: in _check_move_file
shutil.move(src, dst)
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/shutil.py:562: in move
real_dst = os.path.join(dst, _basename(src))
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
path = PosixPath('/var/folders/r2/psq74t5x3nbfzlph8bh2pvdw0000gn/T/tmp9ie0wh9_/foo')
def _basename(path):
# A basename() variant which first strips the trailing slash, if present.
# Thus we always get the last component of the path, even for directories.
sep = os.path.sep + (os.path.altsep or '')
> return os.path.basename(path.rstrip(sep))
E AttributeError: 'PosixPath' object has no attribute 'rstrip'
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/shutil.py:526: AttributeError
============================================== 1 failed, 102 deselected in 0.30 seconds ===============================================
```
After change:
```
========================================================= test session starts =========================================================
platform darwin -- Python 3.7.4, pytest-5.0.1, py-1.8.0, pluggy-0.12.0 -- /Users/maxwellmckinnon/.venvs/TA3.7/bin/python3.7
cachedir: .pytest_cache
rootdir: /Users/maxwellmckinnon/dev/cpython
plugins: cov-2.7.1, mock-1.10.4
collected 103 items / 102 deselected / 1 selected
Lib/test/test_shutil.py::TestMove::test_move_file_pathlike PASSED [100%]
============================================== 1 passed, 102 deselected in 0.06 seconds ===============================================
```
Running all the tests in test_shutil.py
```
╰─ pytest Lib/test/test_shutil.py -v
========================================================= test session starts =========================================================
platform darwin -- Python 3.7.4, pytest-5.0.1, py-1.8.0, pluggy-0.12.0 -- /Users/maxwellmckinnon/.venvs/TA3.7/bin/python3.7
cachedir: .pytest_cache
rootdir: /Users/maxwellmckinnon/dev/cpython
plugins: cov-2.7.1, mock-1.10.4
collected 103 items
Lib/test/test_shutil.py::TestShutil::test_chown PASSED [ 0%]
Lib/test/test_shutil.py::TestShutil::test_copy PASSED [ 1%]
...
Lib/test/test_shutil.py::TermsizeTests::test_stty_match SKIPPED [ 99%]
Lib/test/test_shutil.py::PublicAPITests::test_module_all_attribute PASSED [100%]
================================================ 96 passed, 7 skipped in 1.25 seconds =================================================
```
# Performance Considerations
Is it considered poor form to get rid of _basename altogether and make use of pathlib in the move function? I'm not sure if the idea is for all these modules to strictly avoid circular dependencies. They are already using os.path which is just as much a citizen in 3.8 as pathlib right?
e.g.
`real_dst = os.path.join(dst, _basename(src))`
becomes
`real_dst = Path(dst) / Path(src).name`
I've looked around and familiarized myself, and I now think importing pathlib here is fine. My only remaining concern is that of performance.
Here's the performance difference for this step.
```
In [46]: %timeit real_dst = os.path.join("a/b/c", _basename('b/'))
2.71 µs ± 62.6 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)
In [47]: %timeit real_dst = Path("a/b/c") / Path('b/').name
12.4 µs ± 65.3 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)
```
Is 10us significant or insignificant compared to the least expensive operation this function will do? I don't know. Let's find out.
```
In [55]: %timeit os.rename('/tmp/a/a.txt', '/tmp/a/b.txt'); os.rename('/tmp/a/b.txt', '/tmp/a/a.txt')
124 µs ± 2.18 µs per loop (mean ± std. dev. of 7 runs, 10000 loops each)
```
62us to rename. 10us seems significant enough that we wouldn't want to favor the Path sugar suggestion. 16% speed decrease from adding the 10us.
What do people think? I was hoping to get to use pathlib.Path here, but I suspect for this low level move, it should be as fast as possible, and 16% is not worth one line of sugary code to me.
https://bugs.python.org/issue32689
Automerge-Triggered-By: @gvanrossum
* Raise the limit of maximum path depth to actual recursion limit
* Add posibilities to adjust a path compiled in .pyc file.
Now, you can:
- Strip a part of path from a beggining of path into compiled file
example "-s /test /test/build/real/test.py" → "build/real/test.py"
- Append some new path to a beggining of path into compiled file
example "-p /boo real/test.py" → "/boo/real/test.py"
You can also use both options in the same time. In that case,
striping is done before appending.
* Add a possibility to specify multiple optimization levels
Each optimization level then leads to separated compiled file.
Use `action='append'` instead of `nargs='+'` for the -o option.
Instead of `-o 0 1 2`, specify `-o 0 -o 1 -o 2`. It's more to type,
but much more explicit.
* Add a symlinks limitation feature
This feature allows us to limit byte-compilation of symbolic
links if they are pointing outside specified dir (build root
for example).
Mention frame.f_trace in sys.settrace docs, as well as the fact you still
need to call `sys.settrace` to enable the tracing machinery before setting
`frame.f_trace` will have any effect.
This PR replaces the old note mentioning that `typing` is a provisional module with a new one mentioning types are not enforced at runtime. I am not sure if there was any official announcement about making `typing` non-provisional, but _de-facto_ no new features were added during Python 3.7, and no backwards incompatible changes were made except for few small things that were considered bugs.
* 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.
Ivan Levkivskyi
Serhiy Storchaka
Gregory P. Smith
Samuel Colvin
Kyle Stanley
M. Eric Irrgang
Ricardo Bánffy
Adam J. Stewart
Ashley Whetter
Maxwell A McKinnon
Yury Selivanov
Lisa Roach
Pascal Chambon
Prateek Nayak
Stéphane Wirtel
Lumír 'Frenzy' Balhar
Raymond Hettinger
Emmanuel Arias
Ammar Askar
Ram Rachum
toonarmycaptain
Victor Stinner
Jörn Heissler
Hrvoje Nikšić
Adorilson Bezerra
Anthony Sottile
Eric O. LEBIGOT (EOL)
bchhabra2490
Windson yang
Kexuan Sun
Ashwin Ramaswami
Xtreak
Rémi Lapeyre
Kishore Vancheeshwaran
Christian Heimes
Patrick McLean
Hai Shi
Andrew Svetlov
Julien Palard