The previous `_parse_args()` method pulled the `_parts` out of any supplied `PurePath` objects; these were subsequently joined in `_from_parts()` using `os.path.join()`. This is actually a slower form of joining than calling `fspath()` on the path object, because it doesn't take advantage of the fact that the contents of `_parts` is normalized!
This reduces the time taken to run `PurePath("foo", "bar")` by ~20%, and the time taken to run `PurePath(p, "cheese")`, where `p = PurePath("/foo", "bar", "baz")`, by ~40%.
Automerge-Triggered-By: GH:AlexWaygood
Fix a bug where `Path` takes and ignores `**kwargs` by adding to `PurePath` class `__init__` method which can take only positional arguments.
Automerge-Triggered-By: GH:brettcannon
Increase performance of the `absolute()` method by calling `os.getcwd()` directly, rather than using the `Path.cwd()` class method. This avoids constructing an extra `Path` object (and the parsing/normalization that comes with it).
Decrease performance of the `cwd()` class method by calling the `Path.absolute()` method, rather than using `os.getcwd()` directly. This involves constructing an extra `Path` object. We do this to maintain a longstanding pattern where `os` functions are called from only one place, which allows them to be more readily replaced by users. As `cwd()` is generally called at most once within user programs, it's a good bargain.
```shell
# before
$ ./python -m timeit -s 'from pathlib import Path; p = Path("foo", "bar")' 'p.absolute()'
50000 loops, best of 5: 9.04 usec per loop
# after
$ ./python -m timeit -s 'from pathlib import Path; p = Path("foo", "bar")' 'p.absolute()'
50000 loops, best of 5: 5.02 usec per loop
```
Automerge-Triggered-By: GH:AlexWaygood
Users may wish to define subclasses of `pathlib.Path` to add or modify
existing methods. Before this change, attempting to instantiate a subclass
raised an exception like:
AttributeError: type object 'PPath' has no attribute '_flavour'
Previously the `_flavour` attribute was assigned as follows:
PurePath._flavour = xxx not set!! xxx
PurePosixPath._flavour = _PosixFlavour()
PureWindowsPath._flavour = _WindowsFlavour()
This change replaces it with a `_pathmod` attribute, set as follows:
PurePath._pathmod = os.path
PurePosixPath._pathmod = posixpath
PureWindowsPath._pathmod = ntpath
Functionality from `_PosixFlavour` and `_WindowsFlavour` is moved into
`PurePath` as underscored-prefixed classmethods. Flavours are removed.
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Brett Cannon <brett@python.org>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Eryk Sun <eryksun@gmail.com>
`relative_to()` now treats naked drive paths as relative. This brings its
behaviour in line with other parts of pathlib, and with `ntpath.relpath()`,
and so allows us to factor out the pathlib-specific implementation.
By default, :meth:`pathlib.PurePath.relative_to` doesn't deal with paths that are not a direct prefix of the other, raising an exception in that instance. This change adds a *walk_up* parameter that can be set to allow for using ``..`` to calculate the relative path.
example:
```
>>> p = PurePosixPath('/etc/passwd')
>>> p.relative_to('/etc')
PurePosixPath('passwd')
>>> p.relative_to('/usr')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "pathlib.py", line 940, in relative_to
raise ValueError(error_message.format(str(self), str(formatted)))
ValueError: '/etc/passwd' does not start with '/usr'
>>> p.relative_to('/usr', strict=False)
PurePosixPath('../etc/passwd')
```
https://bugs.python.org/issue40358
Automerge-Triggered-By: GH:brettcannon
Have pathlib use `os.path.join()` to join arguments to the `PurePath` initialiser, which fixes a minor bug when handling relative paths with drives.
Previously:
```python
>>> from pathlib import PureWindowsPath
>>> a = 'C:/a/b'
>>> b = 'C:x/y'
>>> PureWindowsPath(a, b)
PureWindowsPath('C:x/y')
```
Now:
```python
>>> PureWindowsPath(a, b)
PureWindowsPath('C:/a/b/x/y')
```
Have `pathlib.WindowsPath.is_mount()` call `ntpath.ismount()`. Previously it raised `NotImplementedError` unconditionally.
https://bugs.python.org/issue42777
When a `_PathParents` object has a drive or a root, the length of the
object is *one less* than than the length of `self._parts`, which resulted
in an off-by-one error when `path.parents[-n]` was fed through to
`self._parts[:-n - 1]`. In particular, `path.parents[-1]` was a malformed
path object with spooky properties.
This is addressed by adding `len(self)` to negative indices.
We could try to remedy this by taking a slice, but we then run into an issue where the empty string will match altsep on POSIX. That rabbit hole could keep getting deeper.
A proper fix for the original issue involves making pathlib's path normalisation more configurable - in this case we want to retain trailing slashes, but in other we might want to preserve `./` prefixes, or elide `../` segments when we're sure we won't encounter symlinks.
This reverts commit ea2f5bcda1.
Per Pitrou:
> The original intent for the “accessor” thing was to have a variant that did all accesses under a filesystem tree in a race condition-free way using openat and friends. It turned out to be much too hairy to actually implement, so was entirely abandoned, but the accessor abstraction was left there.
https://discuss.python.org/t/make-pathlib-extensible/3428/2
Accessors are:
- Lacking any internal purpose - '_NormalAccessor' is the only implementation
- Lacking any firm conceptual difference to `Path` objects themselves (inc. subclasses)
- Non-public, i.e. underscore prefixed - '_Accessor' and '_NormalAccessor'
- Unofficially used to implement customized `Path` objects, but once once [bpo-24132]() is addressed there will be a supported route for that.
This patch preserves all existing behaviour.
`pathlib.PureWindowsPath.is_reserved()` now identifies as reserved
filenames with trailing spaces or colons.
Co-authored-by: Barney Gale <barney.gale@foundry.com>
Co-authored-by: Eryk Sun <eryksun@gmail.com>
The argument order of `link_to()` is reversed compared to what one may expect, so:
a.link_to(b)
Might be expected to create *a* as a link to *b*, in fact it creates *b* as a link to *a*, making it function more like a "link from". This doesn't match `symlink_to()` nor the documentation and doesn't seem to be the original author's intent.
This PR deprecates `link_to()` and introduces `hardlink_to()`, which has the same argument order as `symlink_to()`.
Previously we had identical behaviour but only allowed accessors to override os.open(). This change allows the override to also construct the IO wrapper as well.
This makes `ntpath.expanduser()` match `pathlib.Path.expanduser()` in this regard, and is more in line with `posixpath.expanduser()`'s cautious approach.
Also remove the near-duplicate implementation of `expanduser()` in pathlib, and by doing so fix a bug where KeyError could be raised when expanding another user's home directory.
See [PEP 597](https://www.python.org/dev/peps/pep-0597/).
* Add `-X warn_default_encoding` and `PYTHONWARNDEFAULTENCODING`.
* Add EncodingWarning
* Add io.text_encoding()
* open(), TextIOWrapper() emits EncodingWarning when encoding is omitted and warn_default_encoding is enabled.
* _pyio.TextIOWrapper() uses UTF-8 as fallback default encoding used when failed to import locale module. (used during building Python)
* bz2, configparser, gzip, lzma, pathlib, tempfile modules use io.text_encoding().
* What's new entry
Barney Gale
Yurii Karabas
Charles Machalow
Nikita Sobolev
domragusa
Stanislav Zmiev
Samuel Sloniker
Serhiy Storchaka
Gregory P. Smith
Eisuke Kawashima
andrei kulakov
Kevin Follstad
Steve Dower
Inada Naoki