Split UV_INDEX on all whitespace

[winstonallo]

Summary

Closes #12806

Split UV_INDEX by any whitespace rather than only ASCII 32, which does not align with the behavior of PIP_EXTRA_INDEX_URL and can possibly lead to difficulties when migrating from pip to uv.

Clap unfortunately does not support passing multiple delimiters, writing a custom parsing function involved parsing index into a Vec<Vec> and flattening it afterwards in order to avoid breaking the --index command line option.

There might be a prettier solution I overlooked, let me know if there is anything I should change!

[Gankra]

Could you add a test that's a copy of repeated_index_cli that tests the new whitespace support?

uv/crates/uv/tests/it/edit.rs

Lines 9948 to 9956 in 7a18e44

	/// If an index is repeated on the CLI, the last-provided index should take precedence.
	///
	/// The index that appears in the `pyproject.toml` should also be consistent with the index that
	/// appears in the `uv.lock`.
	///
	/// See: <https://github.com/astral-sh/uv/issues/11312>
	#[test]
	fn repeated_index_cli() -> Result<()> {
	let context = TestContext::new("3.12");

(see repeated_index_cli_environment_variable for an example of how to set env vars in invocations -- note that it uses UV_DEFAULT_INDEX and you want UV_INDEX)

[Gankra]

Oops this looks like a mistake

[winstonallo]

Yes haha, fixed

[Gankra]

Might be nice to add some more context here to note that this function exists because clap value_delimiter only lets you split on a single character, and we need to split on all whitespace (notably spaces OR newlines).

And also that the --index arguments have to have a Vec<Vec<Maybe<Index>>> because when clap parses an environment variable with value_parser it expects to only parse one value.

[Gankra]

Suggested change

	///
	/// The nested Vec structure (`Vec<Vec<Maybe<Index>>>`) is required for clap's
	/// value parsing mechanism, which processes one value at a time, in order to handle
	/// `UV_INDEX` the same way pip handles `PIP_EXTRA_INDEX_URL`.
	//
	// The nested Vec structure (`Vec<Vec<Maybe<Index>>>`) is required for clap's
	// value parsing mechanism, which processes one value at a time, in order to handle
	// `UV_INDEX` the same way pip handles `PIP_EXTRA_INDEX_URL`.

[Gankra]

(This kind of detail shouldn't be part of --help)

[Gankra]

Thanks for the quick and evil fix!

[winstonallo]

Thanks for the quick and evil fix!

Thank you for your quick feedback :))