Improve performance of pathlib.Path.absolute() #100562
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3.12
only security fixes
performance
Performance or resource usage
topic-pathlib
type-feature
A feature request or enhancement
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AlexWaygood
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barneygale
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Dec 28, 2022
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.
AlexWaygood
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Jan 5, 2023
miss-islington
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Jan 5, 2023
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
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The current implementation of
pathlib.Path.absolute()callsself.cwd()rather thanos.getcwd(), and so constructs twoPathobjects rather than one. As path objects are slow to construct, this has a performance impact.Linked PRs
pathlib.Path.absolute()#100563The text was updated successfully, but these errors were encountered: