Package multiple license files in .dist-info

[idavis]

Summary

Add support for license-files option in metadata for PEP 639 so that licenses are added to the .dist-info wheel folder. This extends the work of #837 (#829).

There are three separate pieces covered here:

• Supporting license-files.paths
• Supporting license-files.globs
• Supporting convention for automatically including license files

I think a minimum version of this feature with the highest return would be to add the convention for automatically including license files with the license-files option being treated as dynamic to trigger the default behavior. I have a working spike of the implementation but I need to write tests.

Looking through the code, we'd need to add license-files to the pyproject-toml-rs project to deal with serializing the new metadata option to unblock support for license-files.(paths|globs) which can build on the work done in #837 to append the license files to the merging metadata.

Current State

The single license specified in the pyproject.toml will be copied into the .dist-info wheel folder:

[project]
license = {file = "LICENSE"}

Desired State

The link used for multiple file use in #837 is broken (and in the code). The advanced example for PEP 639 shows the use of license-files.paths or license-files.globs for listing multiple licenses:

Example with notice:

[project]
license-files.paths = [
    "LICENSE",
    "NOTICE.txt",
]

Multiple license files:

[project]
license-files.paths = [
    "LICENSE",
    "_vendor/LICENSE",
    "_vendor/LICENSE.APACHE",
    "_vendor/LICENSE.BSD",
]

Or alternatively, matched via glob patterns:

[project]
license-files.globs = [
    "LICENSE*",
    "_vendor/LICENSE*",
]

PEP 649 - I maintain an existing package that’s already licensed gives further defaults used by setuptools for automatically including these files.

[messense]

Thanks for the issue, feel free to implement it and send PRs.

[idavis]

@messense I have created a PR for Adding license_expression and license_files serialization to support this work in the PyO3/pyproject-toml-rs repo.

[idavis]

@messense Submitted PR #862 which has just the default license packaging from PEP 639. The other items in this issue require the serialization updates.