tarfile: Fix FileSection.skip to not rely on extended readinto args. #1069
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Tests TarFile iteration and extracting file information. Signed-off-by: Damien George <damien@micropython.org>
Commit 2ca1527 optimized `FileSection.skip()` for memory use. But that introduced a dependency on the MicroPython-extension to stream read methods for an additional argument specifying a maximum read size. This optimization meant that all file-like objects passed into TarFile must support the extended 2-argument `readinto` form. This is problematic for at least two use cases: 1. Nested tar files, because `FileSetion` itself doesn't support 2-argument `readinto`. 2. Using `mpremote mount` and reading a tar file from the remote mount, which also doesn't support 2-argument `readinto`. Instead of requiring all file-like objects to implement this extended form of `readinto`, this commit changes `FileSection.skip()` so that it doesn't use this form. A test is added for this case which fails without the fix here. Signed-off-by: Damien George <damien@micropython.org>
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Alternative to #1032. |
projectgus
approved these changes
Dec 3, 2025
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Commit 2ca1527 optimized
FileSection.skip()for memory use. But that introduced a dependency on the MicroPython-extension to stream read methods for an additional argument specifying a maximum read size. This optimization meant that all file-like objects passed into TarFile must support the extended 2-argumentreadintoform.This is problematic for at least two use cases:
FileSetionitself doesn't support 2-argumentreadinto.mpremote mountand reading a tar file from the remote mount, which also doesn't support 2-argumentreadinto.Instead of requiring all file-like objects to implement this extended form of
readinto, this commit changesFileSection.skip()so that it doesn't use this form.A test is added for this case which fails without the fix here.