Document that datasets support pathlib.Path

[NicolasHug]

All datasets' root param already supports pathlib.Path because they just call os.expanduser() under the hood, which will nicely handle Path. So this PR just adds that to the docstrings.

This isn't explicitly tested, but #8320 should prove that Path works fine (@pmeier if there's a better way to test that consistently, LMK).

I'm not updating the type annotations because in all honestly I really, REALLY don't want to spend my time doing that. I gave it a go adding the annotations mentioned in #8120 (comment) to just the imagenet file, and after running for 3+ minutes mypy started to give me hell. So I'm just not doing it. If someone wants to spend the time and add the annotations, I'll be happy to stamp the PR.

With that and #8314, #8120 could be closed.

[pytorch-bot]

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❌ 16 New Failures, 21 Unrelated Failures

As of commit fdf85eb with merge base 0325175 ():

NEW FAILURES - The following jobs have failed:

• CMake / macos (macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• CMake / macos (macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• CMake / windows (windows.4xlarge, cpu) / windows-job (gh)
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• CMake / windows (windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
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• Lint / bc (gh)
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• Tests / unittests-macos (3.10, macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• Tests / unittests-macos (3.11, macos-12) / macos-job (gh)
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• Tests / unittests-macos (3.12, macos-12) / macos-job (gh)
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• Tests / unittests-macos (3.8, macos-12) / macos-job (gh)
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• Tests / unittests-macos (3.9, macos-12) / macos-job (gh)
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• Tests / unittests-windows (3.10, windows.4xlarge, cpu) / windows-job (gh)
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• Tests / unittests-windows (3.11, windows.4xlarge, cpu) / windows-job (gh)
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• Tests / unittests-windows (3.12, windows.4xlarge, cpu) / windows-job (gh)
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• Tests / unittests-windows (3.8, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.8, windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
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• Tests / unittests-windows (3.9, windows.4xlarge, cpu) / windows-job (gh)
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FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• CMake / linux (linux.12xlarge, cpu) / linux-job (gh)
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• CMake / linux (linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh)
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• Docs / build / linux-job (gh)
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• Lint / c-source / linux-job (gh)
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• Lint / python-source-and-configs / linux-job (gh)
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• Lint / python-types / linux-job (gh)
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• Prototype tests on Linux / unittests-prototype (3.10, linux.12xlarge, cpu) / linux-job (gh)
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• Prototype tests on Linux / unittests-prototype (3.11, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.12, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.8, linux.12xlarge, cpu) / linux-job (gh)
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• Prototype tests on Linux / unittests-prototype (3.8, linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh)
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• Prototype tests on Linux / unittests-prototype (3.9, linux.12xlarge, cpu) / linux-job (gh)
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• Tests / onnx / linux-job (gh)
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• Tests / unittests-extended / linux-job (gh)
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• Tests / unittests-linux (3.10, linux.12xlarge, cpu) / linux-job (gh)
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• Tests / unittests-linux (3.11, linux.12xlarge, cpu) / linux-job (gh)
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• Tests / unittests-linux (3.8, linux.12xlarge, cpu) / linux-job (gh)
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• Tests / unittests-linux (3.8, linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh)
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• Tests / unittests-linux (3.9, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128

BROKEN TRUNK - The following job failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• Tests / unittests-macos (3.8, macos-m1-stable) / macos-job (gh)

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[vfdev-5]

Can you post here some of the mypy errors you see with imagenet and updated typing hints?

[NicolasHug]

Sorry, mypy takes 3+ minutes to run on my machine and honestly I just don't want to go back to it knowing that I won't be addressing type annotations for all those 40+ files anyway.

[pmeier]

I've added the type annotations. Regarding testing, #8320 is what I would have done as well. If you want the extra security, we could potentially implement a smoke test for that, but not sure if its worth it.

[pmeier]

BC linter fails with these warnings:

Warning: Function find_classes: directory changed from str to Union[str, Path]
Warning: Function make_dataset: directory changed from str to Union[str, Path]
Warning: Function DatasetFolder.make_dataset: directory changed from str to Union[str, Path]
Warning: Function DatasetFolder.find_classes: directory changed from str to Union[str, Path]
Warning: Function load_meta_file: root changed from str to Union[str, Path]
Warning: Function parse_devkit_archive: root changed from str to Union[str, Path]
Warning: Function parse_train_archive: root changed from str to Union[str, Path]
Warning: Function parse_val_archive: root changed from str to Union[str, Path]

Yes, annotations have changed, but they were expanded. Passing str is still fully acceptable.

[pmeier]

Here is the green mypy job.

[NicolasHug]

Thanks @pmeier

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