GH-125413: Add private metadata methods to pathlib.Path.info
#129897
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Add the following private methods to `pathlib.Path.info`: - `_get_mode()`: returns the POSIX file mode (`st_mode`), or zero if `os.stat()` fails. - `_get_times_ns()`: returns the access and modify times in nanoseconds (`st_atime_ns` and `st_mtime_ns`), or zeroes if `os.stat()` fails. - `_get_flags()`: returns the BSD file flags (`st_flags`), or zero if `os.stat()` fails. - `_get_xattrs()`: returns the file extended attributes as a list of key, value pairs, or an empty list if `listxattr()` or `getattr()` fail. These methods replace `LocalCopyReader.read_metadata()`, and so we can delete the `CopyReader` and `LocalCopyReader` classes. Rather than reading metadata via `source._copy_reader.read_metadata()`, we instead call `source.info._get_mode()`, `_get_times_ns()`, etc. Copying metadata is only supported for local-to-local copies at the moment. To support copying between arbitrary `ReadablePath` and `WritablePath` objects, we'd need to make the new methods public and documented.
(not 100% sure about this)
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Should
Is that the plan? It seems to me that people will want their subclasses to support such copying, and are might resort to underscored functions to get it. |
Sounds good to me. Would we (eventually) document it as returning
Yes, I think it will be part of the PEP for making Joinable/Readable/WritablePath public. |
The tuple for the local FS†, a comparable/hashable object in general? I can imagine a path class that would add extra functionality to Path (or limit the functionality), but expose local files. |
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Thanks :) I've deleted |
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Thanks for the review! |
Replace `WritablePath._copy_writer` with a new `_write_info()` method. This method allows the target of a `copy()` to preserve metadata. Replace `pathlib._os.CopyWriter` and `LocalCopyWriter` classes with new `copy_file()` and `copy_info()` functions. The `copy_file()` function uses `source_path.info` wherever possible to save on `stat()`s.
Add the following private methods to
pathlib.Path.info:_posix_permissions(): the POSIX file permissions (S_IMODE(st_mode))_file_id(): the file ID ((st_dev, st_ino))_access_time_ns(): the access time in nanoseconds (st_atime_ns)_mod_time_ns(): the modify time in nanoseconds (st_mtime_ns)_bsd_flags(): the BSD file flags (st_flags)_xattrs(): the file extended attributes as a list of key, value pairs, or an empty list iflistxattr()orgetxattr()fail in an ignorable way.These methods replace
LocalCopyReader.read_metadata(), and so we can delete theCopyReaderandLocalCopyReaderclasses. Rather than reading metadata viasource._copy_reader.read_metadata(), we instead callsource.info._posix_permissions(),_access_time_ns(), etc.Preserving metadata is only supported for local-to-local copies at the moment. To support copying metadata between arbitrary
ReadablePathandWritablePathobjects, we'd need to make the new methods public and documented.os.DirEntryobjects from pathlib #125413