GH-119169: Implement `pathlib.Path.walk()` using `os.walk()` (GH-119573)
For silly reasons, pathlib's generic implementation of `walk()` currently
resides in `glob._Globber`. This commit moves it into
`pathlib._abc.PathBase.walk()` where it really belongs, and makes
`pathlib.Path.walk()` call `os.walk()`.
(cherry picked from commit 7ff61f51b6)
Co-authored-by: Barney Gale <barney.gale@gmail.com>
Restore behaviour from 3.12 when `path.with_suffix(None)` is called.
(cherry picked from commit 3c28510b98)
Co-authored-by: Barney Gale <barney.gale@gmail.com>
Moving this code under the `pathlib` package makes it quite a lot easier
to backport in the `pathlib-abc` PyPI package. It was a bit foolish of me
to add it to `glob` in the first place.
Also add `translate()` to `__all__` in `glob`. This function is new in
3.13, so there's no NEWS needed.
* docs: tiny grammar change: "pointed by" -> "pointed to by"
This commit uses "file pointed to by" to replace "file pointed by" in
- doc for shutil.copytree
- docstring for shutil.copytree
- docstring _abc.PathBase.open
- docstring for pathlib.Path.open
- doc for os.copy_file_range
- doc for os.splice
The docs use "file pointed to by" more frequently than
"file pointed by". So, this commit replaces the uses of
"file pointed by" in order to make the uses consistent
through the docs.
```bash
$ grep -ri 'pointed to by' cpython/
```
yields more results than
```bash
$ grep -ri 'pointed by' cpython/
```
Separately:
There are two occurrences of "tree pointed by":
- cpython/Doc/library/xml.etree.elementtree.rst for
`xml.etree.ElementInclude.include`
- cpython/Lib/xml/etree/ElementInclude.py for `include`
For those uses of "tree pointed by", I expect "tree pointed to by"
instead. However, I found enough uses online of (a) "tree pointed by"
rather than (b) "tree pointed to by" to convince me that (a) is in
common use.
So, this commit does not replace those occurrences of "tree pointed by"
to "tree pointed to by". But I will replace them if a reviewer
believes it is correct to replace them.
* docs: typo: "exists and executable" -> "exists and is executable"
---------
Co-authored-by: Andrew-Zipperer <atzipperer@gmail.com>
The second item in the tuple returned from `__reduce__()` is a tuple of arguments to supply to path constructor. Previously we returned the `parts` tuple here, which entailed joining, parsing and normalising the path object, and produced a compact pickle representation.
With this patch, we instead return a tuple of paths that were originally given to the path constructor. This makes pickling much faster (at the expense of compactness).
It's worth noting that, in the olden times, pathlib performed this parsing/normalization up-front in every case, and so using `parts` for pickling was almost free. Nowadays pathlib only parses/normalises paths when it's necessary or advantageous to do so (e.g. computing a path parent, or iterating over a directory, respectively).
Since 6258844c, paths that might not exist can be fed into pathlib's
globbing implementation, which will call `os.scandir()` / `os.lstat()` only
when strictly necessary. This allows us to drop an initial `self.is_dir()`
call, which saves a `stat()`.
Co-authored-by: Shantanu <12621235+hauntsaninja@users.noreply.github.com>
Replace use of `os.listdir()` with `os.scandir()`. Forgo setting `_drv`,
`_root` and `_tail_cached`, as these usually aren't needed. Use
`os.DirEntry.path` to set `_str`.
Don't bother calling `os.scandir()` to scan for literal pattern segments,
like `foo` in `foo/*.py`. Instead, append the segment(s) as-is and call
through to the next selector with `exists=False`, which signals that the
path might not exist. Subsequent selectors will call `os.scandir()` or
`os.lstat()` to filter out missing paths as needed.
Move `pathlib.Path.walk()` implementation into `glob._Globber`. The new
`glob._Globber.walk()` classmethod works with strings internally, which is
a little faster than generating `Path` objects and keeping them normalized.
The `pathlib.Path.walk()` method converts the strings back to path objects.
In the private pathlib ABCs, our existing subclass of `_Globber` ensures
that `PathBase` instances are used throughout.
Follow-up to #117589.
Move pathlib globbing implementation into a new private class: `glob._Globber`. This class implements fast string-based globbing. It's called by `pathlib.Path.glob()`, which then converts strings back to path objects.
In the private pathlib ABCs, add a `pathlib._abc.Globber` subclass that works with `PathBase` objects rather than strings, and calls user-defined path methods like `PathBase.stat()` rather than `os.stat()`.
This sets the stage for two more improvements:
- GH-115060: Query non-wildcard segments with `lstat()`
- GH-116380: Unify `pathlib` and `glob` implementations of globbing.
No change to the implementations of `glob.glob()` and `glob.iglob()`.
Replace tri-state `follow_symlinks` with boolean `recurse_symlinks` argument. The new argument controls whether symlinks are followed when expanding recursive `**` wildcards. The possible argument values correspond as follows:
follow_symlinks recurse_symlinks
=============== ================
False N/A
None False
True True
We therefore drop support for not following symlinks when expanding non-recursive pattern parts; it wasn't requested in the original issue, and it's a feature not found in any shells.
This makes the API a easier to grok by eliminating `None` as an option.
No news blurb as `follow_symlinks` was new in 3.13.
Switch the default value of *follow_symlinks* from `None` to `True` in
`pathlib._abc.PathBase.glob()` and `rglob()`. This speeds up recursive
globbing.
No change to the public pathlib classes.
When expanding and filtering paths for a `**` wildcard segment, build an `re.Pattern` object from the subsequent pattern parts, rather than the entire pattern, and match against the `os.DirEntry` object prior to instantiating a path object. Also skip compiling a pattern when expanding a `*` wildcard segment.
When expanding `**` wildcards, ensure we add a trailing slash to the
topmost directory path. This matches `glob.glob()` behaviour:
>>> glob.glob('dirA/**', recursive=True)
['dirA/', 'dirA/dirB', 'dirA/dirB/dirC']
This does not affect `pathlib.Path.glob()`, because trailing slashes aren't
supported in pathlib proper.
Methods like `full_match()`, `glob()`, etc, are difficult to make work with
byte paths, and it's not worth the effort. This patch makes `PurePathBase`
raise `TypeError` when given non-`str` path segments.
Raise `UnsupportedOperation` directly, rather than via an `_unsupported()`
helper, to give human readers and IDEs/typecheckers/etc a bigger hint that
these methods are abstract.
Return files and directories from `pathlib.Path.glob()` if the pattern ends
with `**`. This is more compatible with `PurePath.full_match()` and with
other glob implementations such as bash and `glob.glob()`. Users can add a
trailing slash to match only directories.
In my previous patch I added a `FutureWarning` with the intention of fixing
this in Python 3.15. Upon further reflection I think this was an
unnecessarily cautious remedy to a clear bug.
Raise `ValueError` if `with_suffix('.ext')` is called on a path without a
stem. Paths may only have a non-empty suffix if they also have a non-empty
stem.
ABC-only bugfix; no effect on public classes.
Remove `self.joinpath('')` call that should have been removed in 6313cdde.
This makes `PathBase.glob('')` yield itself *without* adding a trailing slash. It's hard to say whether this is more or less correct, but at least everything else is faster, and there's no behaviour change in the public classes where empty glob patterns are disallowed.
Add `ntpath.isreserved()`, which identifies reserved pathnames such as "NUL", "AUX" and "CON".
Deprecate `pathlib.PurePath.is_reserved()`.
---------
Co-authored-by: Eryk Sun <eryksun@gmail.com>
Co-authored-by: Brett Cannon <brett@python.org>
Co-authored-by: Steve Dower <steve.dower@microsoft.com>
In 49f90ba we added support for the recursive wildcard `**` in
`pathlib.PurePath.match()`. This should allow arbitrary prefix and suffix
matching, like `p.match('foo/**')` or `p.match('**/foo')`, but there's a
problem: for relative patterns only, `match()` implicitly inserts a `**`
token on the left hand side, causing all patterns to match from the right.
As a result, it's impossible to match relative patterns from the left:
`PurePath('foo/bar').match('bar/**')` is true!
This commit reverts the changes to `match()`, and instead adds a new
`full_match()` method that:
- Allows empty patterns
- Supports the recursive wildcard `**`
- Matches the *entire* path when given a relative pattern
Use `_make_child_entry()` rather than `_make_child_relpath()` to retrieve
path objects for directories to visit. This saves the allocation of one
path object per directory in user subclasses of `PathBase`, and avoids a
second loop.
This trick does not apply when walking top-down, because users can affect
the walk by modifying *dirnames* in-place.
A side effect of this change is that, in bottom-up mode, subdirectories of
each directory are visited in reverse order, and that this order doesn't
match that of the names in *dirnames*. I suspect this is fine as the
order is arbitrary anyway.
Allow `os.PathLike` objects to be passed as patterns to `pathlib.Path.glob()` and `rglob()`. (It's already possible to use them in `PurePath.match()`)
While we're in the area:
- Allow empty glob patterns in `PathBase` (but not `Path`)
- Speed up globbing in `PathBase` by generating paths with trailing slashes only as a final step, rather than for every intermediate directory.
- Simplify and speed up handling of rare patterns involving both `**` and `..` segments.
This allows users of the `pathlib-abc` PyPI package to use `posixpath` or
`ntpath` as a path module in versions of Python lacking
`os.path.splitroot()` (3.11 and before).
Path modules provide a subset of the `os.path` API, specifically those
functions needed to provide `PurePathBase` functionality. Each
`PurePathBase` subclass references its path module via a `pathmod` class
attribute.
This commit adds a new `PathModuleBase` class, which provides abstract
methods that unconditionally raise `UnsupportedOperation`. An instance of
this class is assigned to `PurePathBase.pathmod`, replacing `posixpath`.
As a result, `PurePathBase` is no longer POSIX-y by default, and
all its methods raise `UnsupportedOperation` courtesy of `pathmod`.
Users who subclass `PurePathBase` or `PathBase` should choose the path
syntax by setting `pathmod` to `posixpath`, `ntpath`, `os.path`, or their
own subclass of `PathModuleBase`, as circumstances demand.
It's wrong for the `PurePathBase` methods to rely so much on `__str__()`.
Instead, they should treat the raw path(s) as opaque objects and leave the
details to `pathmod`.
This commit adds a `PurePathBase._raw_path` property and uses it through
many of the other ABC methods. These methods are all redefined in
`PurePath` and `Path`, so this has no effect on the public classes.
On Windows, `os.path.isabs()` now returns `False` when given a path that
starts with exactly one (back)slash. This is more compatible with other
functions in `os.path`, and with Microsoft's own documentation.
Also adjust `pathlib.PureWindowsPath.is_absolute()` to call
`ntpath.isabs()`, which corrects its handling of partial UNC/device paths
like `//foo`.
Co-authored-by: Jon Foster <jon@jon-foster.co.uk>
Refuse to guess what a user means when they initialise a pathlib ABC
without any positional arguments. In mainline pathlib it's normalised to
`.`, but in the ABCs this guess isn't appropriate; for example, the path
type may not represent the current directory as `.`, or may have no concept
of a "current directory" at all.
Apply pathlib's normalization and performance tuning in `pathlib.PurePath`, but not `pathlib._abc.PurePathBase`.
With this change, the pathlib ABCs do not normalize away alternate path separators, empty segments, or dot segments. A single string given to the initialiser will round-trip by default, i.e. `str(PurePathBase(my_string)) == my_string`. Implementors can set their own path domain-specific normalization scheme by overriding `__str__()`
Eliminating path normalization makes maintaining and caching the path's parts and string representation both optional and not very useful, so this commit moves the `_drv`, `_root`, `_tail_cached` and `_str` slots from `PurePathBase` to `PurePath`. Only `_raw_paths` and `_resolving` slots remain in `PurePathBase`. This frees the ABCs from the burden of some of pathlib's hardest-to-understand code.
Restore full battle-tested implementations of `PurePath.[is_]relative_to()`. These were recently split up in 3375dfe and a15a773.
In `PurePathBase`, add entirely new implementations based on `_stack`, which itself calls `pathmod.split()` repeatedly to disassemble a path. These new implementations preserve features like trailing slashes where possible, while still observing that a `..` segment cannot be added to traverse an empty or `.` segment in *walk_up* mode. They do not rely on `parents` nor `__eq__()`, nor do they spin up temporary path objects.
Unfortunately calling `pathmod.relpath()` isn't an option, as it calls `abspath()` and in turn `os.getcwd()`, which is impure.
Implement `parts` using `_stack`, which itself calls `pathmod.split()`
repeatedly. This avoids use of `_tail`, which will be moved to `PurePath`
shortly.
- Add `__slots__` to dummy path classes.
- Return namedtuple rather than `os.stat_result` from `DummyPath.stat()`.
- Reduce maximum symlink count in `DummyPathWithSymlinks.resolve()`.
Replace use of `_from_parsed_parts()` with `with_segments()` in
`PurePathBase.relative_to()`, and move the assignment of `_drv`, `_root`
and `_tail_cached` slots into `PurePath.relative_to()`.
Raise auditing events in `pathlib.Path.glob()`, `rglob()` and `walk()`,
but not in `pathlib._abc.PathBase` methods. Also move generation of a
deprecation warning into `pathlib.Path` so it gets the right stack level.
The `pathlib._abc` module will be made available as a PyPI backport
supporting Python 3.8+. The `warnings._deprecated()` function was only
added last year, and it's private from an external package perspective, so
here we switch to `warnings.warn()` instead.
Do not use the locale-specific default encoding in `PathBase.read_text()`
and `write_text()`. Locale settings shouldn't influence the operation of
these base classes, which are intended mostly for implementing rich paths
on *nonlocal* filesystems.
Change the value of `pathlib._abc.PurePathBase.pathmod` from `os.path` to
`posixpath`.
User subclasses of `PurePathBase` and `PathBase` previously used the host
OS's path syntax, e.g. backslashes as separators on Windows. This is wrong
in most use cases, and likely to catch developers out unless they test on
both Windows and non-Windows machines.
In this patch we change the default to POSIX syntax, regardless of OS. This
is somewhat arguable (why not make all aspects of syntax abstract and
individually configurable?) but an improvement all the same.
This change has no effect on `PurePath`, `Path`, nor their subclasses. Only
private APIs are affected.
`PurePathBase.__repr__()` produces a string like `MyPath('/foo')`. This
repr is incorrect/misleading when a subclass's `__init__()` method is
customized, which I expect to be the very common.
This commit moves the `__repr__()` method to `PurePath`, leaving
`PurePathBase` with the default `object` repr.
No user-facing changes because the `pathlib._abc` module remains private.
Miss Islington (bot)
Barney Gale
Andrew Zipperer