Inconsistent behaviour between `pathlib.PurePath.match` and `glob.glob`

[zhukoff-pavel]

Bug report

Bug description:

Prerequisites

Hello! I have a structure of directories as follows:

% tree
.
└── a
    └── b
        └── c
            └── d
                └── e

Problem

Here Pathlib.PurePath a/b/c/d/e won't match with **/b/c/**, but will match with **/c/d/**:

Python 3.12.3 (main, Apr  9 2024, 08:09:14) [Clang 15.0.0 (clang-1500.3.9.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pathlib
>>> path = pathlib.PurePath("a/b/c/d/e")
>>> path.match("**/b/c/**")
False
>>> path.match("**/c/d/**")
True

However, glob on this structure yields different results:

>>> import glob
>>> glob.glob("**/b/c/**")
['a/b/c/d']
>>> glob.glob("**/c/d/**")
[]
>>> glob.glob("**/b/c/**", recursive=True)
['a/b/c/', 'a/b/c/d', 'a/b/c/d/e']
>>> glob.glob("**/c/d/**", recursive=True)
['a/b/c/d/', 'a/b/c/d/e']

i.e. **/b/c/** and **/c/d/** will match to the named path only in recursive mode.

Ideas

I'd expect pathlib.match to behave more like recursive glob.glob (as in prior code block) or pathlib.Path.glob:

>>> sorted(pathlib.Path(".").glob("**/b/c/**"))
[PosixPath('a/b/c'), PosixPath('a/b/c/d'), PosixPath('a/b/c/d/e')]
>>> sorted(pathlib.Path(".").glob("**/c/d/**"))
[PosixPath('a/b/c/d'), PosixPath('a/b/c/d/e')]

CPython versions tested on:

3.10, 3.12

Operating systems tested on:

Linux, macOS

Linked PRs

• [3.12] GH-118701: Note that recursive wildcards aren't supported in PurePath.match() #118713

[zhukoff-pavel]

Follow-up: May be connected with #106747

[sobolevn]

cc @barneygale

[barneygale]

PurePath.match() has a couple of important differences from Path.glob() and glob.glob():

1. Recursive expansion isn't supported, and so ** wildcards work exactly like *
2. If a relative pattern is given, matching is performed from the right

Could you try using Path.full_match() in an alpha or (upcoming) beta of 3.13? I think it does what you want:

>>> import pathlib
>>> path = pathlib.PurePath("a/b/c/d/e")
>>> path.full_match("**/b/c/**")
True
>>> path.full_match("**/c/d/**")
True

[zhukoff-pavel]

Recursive expansion isn't supported, and so ** wildcards work exactly like *

Oh, I see. So, this is intended. Thank you for quick reply!

Is it possible then to add this note to the documentation of previous Python versions? (e.g. Python 3.12)

By the way, side-question regarding naming: Doesn't full_match sound more strict than just match? :)
full_match seems more relaxed than the regular match, because of allowing for recursive patterns to be used, thus allowing more matches per recursive glob.

[barneygale]

By the way, side-question regarding naming: Doesn't full_match sound more strict than just match? :) full_match seems more relaxed than the regular match, because of allowing for recursive patterns to be used, thus allowing more matches per recursive glob.

full_match() matches against the entire path, whereas match() matches from the right, so:

>>> from pathlib import PurePath
>>> PurePath('foo/bar.py').match('*.py')
True
>>> PurePath('foo/bar.py').full_match('*.py')
False

It's analogous to re.match() vs re.fullmatch().

Support for recursive ** wildcards only really makes sense once you eliminate the right-hand-side matching, otherwise all your patterns have an implicit **/ prefix, which makes it much less useful.

[zhukoff-pavel]

I see now.

Thank you for detailed explanations and for documenting!

[barneygale]

No worries, thank you very much for the report :)