UV_INDEX breaks when using newlines as delimiters

[winstonallo]

Summary

Hey, we are migrating our Dockerfiles from pip to uv (lifechanging by the way), and when assigning the value of our PIP_EXTRA_INDEX_URL to UV_INDEX, we noticed that URLs were being merged:

DEBUG No cache entry for: https://****/00000/packages/pypi/simple/internal-package
DEBUG No cache entry for: https://****/11111/packages/pypi/simplehttps://****/22222/packages/pypi/simple/internal-package

The difference is that 00000 and 11111 are separated by a normal whitespace, while 11111 and 22222 are separated by a newline. pip has no issue with newline-separated indices, so it might be cool to support them as well to make the jump to uv even easier.

If this is something you would like to support, feel free to assign me this and I will be happy to make a PR! clap::Arg's value_delimiter only supports single characters I believe (here), but I could write a custom parsing function :)

Sorry in advance if this was reported before 😅

Platform

Debian Bookworm

Version

0.6.14

Python version

3.12

[Gankra]

Would definitely appreciate a patch for this, cleaner migration is always great.