* math.perm() and math.comb()
* math.isqrt()
* Add singledispatchmethod()
* itertools.accumulate()
* Optional headers for xmlrpc.client.ServerProxy
* IDLE non-BMP characters
* import collections.abc directly
* @coroutine is deprecated
* pprint.pp()
* New options for object.__reduce__()
* DictReader no longer returns OrderedDicts
* "force" option for logging.basicConfig()
* Fix spelling
* cProfile context manager
* Various markup/grammar fixes from Kyle Stanley.
Other minor fixes as well.
Also, dedup the __reduce__ entry.
* Fix markup
* Fix grammar nits found by MS Word
Also updates the documentation to clarify the situation surrounding
the digestmod parameter that is required despite its position in the
argument list as of 3.8.0 as well as removing old python2 era
references to "binary strings".
We indavertently had this raise ValueError in 3.8.0 for the missing
arg. This is not considered an API change as no reasonable code would
be catching this missing argument error in order to handle it.
Add a total_nframe field to the traces collected by the tracemalloc module.
This field indicates the original number of frames before it was truncated.
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outdated comment in the library reference.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
For now, we'll rely on the fact that the config structures aren't covered by the stable ABI.
We may revisit this in the future if we further explore the idea of offering a stable embedding API.
(cherry picked from commit bdace21b76)
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
Fix warnings options priority: PyConfig.warnoptions has the highest
priority, as stated in the PEP 587.
* Document options order in PyConfig.warnoptions documentation.
* Make PyWideStringList_INIT macro private: replace "Py" prefix
with "_Py".
* test_embed: add test_init_warnoptions().
Add a new struct_size field to PyPreConfig and PyConfig structures to
allow to modify these structures in the future without breaking the
backward compatibility.
* Replace private _config_version field with public struct_size field
in PyPreConfig and PyConfig.
* Public PyPreConfig_InitIsolatedConfig() and
PyPreConfig_InitPythonConfig()
return type becomes PyStatus, instead of void.
* Internal _PyConfig_InitCompatConfig(),
_PyPreConfig_InitCompatConfig(), _PyPreConfig_InitFromConfig(),
_PyPreConfig_InitFromPreConfig() return type becomes PyStatus,
instead of void.
* Remove _Py_CONFIG_VERSION
* Update the Initialization Configuration documentation.
* 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).