feature request: emit index urls in uv export same way as uv pip compile --emit-index-url

[Fogapod]

I am exporting uv.lock to requirements.txt for bazel.
I have torch index overrides which aren't exported and produce impossible to insall requirements file:

[tool.uv.sources]
torch = [
    { index = "pytorch-cpu" },
]

[[tool.uv.index]]
name = "pytorch-cpu"
url = "https://download.pytorch.org/whl/cpu"
explicit = true

results in:

torch==2.5.1+cpu \
    --hash=sha256:4856f9d6925121d13c2df07aa7580b767f449dfe71ae5acde9c27535d5da4840 \
    --hash=sha256:a6b720410350765d3d77c01a5ce098a6c45af446284e45e87a98b8a16e7d564d

Looks like lock file contains index info so this should be possible:

[[package]]
name = "torch"
version = "2.5.1+cpu"
source = { registry = "https://download.pytorch.org/whl/cpu" }

This probably isn't as simple as writing all indexes to requirements file because ordering matters. Maybe there could be a way to manually give it indexes instead?

[ant0nsc]

+1 on this issue. We have the exactly same problem with multiple indexes that contain different flavours of torch. It would be great to be able to export a requirements file that contains the full URL where uv is taking the package from.
The format of a requirements.txt file does support supplying the full URL: https://pip.pypa.io/en/stable/reference/requirements-file-format/