Documentation: Package Id Spec `kind` lists `file` as an option instead of `path`

[Skgland]

Problem

While working on rust-lang/crater#758 in noticed that https://doc.rust-lang.org/cargo/reference/pkgid-spec.html defines kind as

kind = "registry" | "git" | "file"

but based on the examples I think it should be

kind = "registry" | "git" | "path"

[epage]

I've posted #15049 for the docs but have you considered using PackageIdSpec::parse?

[Skgland]

I have not as I wasn't aware of it, that appears to be a better option.

[Skgland]

@epage it looks like the sparse kind for the sparse registry protocol is also missing

The index key should be a URL to a git repository with the registry’s index or a Cargo sparse registry URL with the sparse+ prefix.
- https://doc.rust-lang.org/cargo/reference/registries.html#using-an-alternate-registry

[epage]

iirc we paper over that difference when it comes to PackageIdSpec, e.g. I ran cargo pkgid <registry-dep> and got back a registry+https:// prefix

[Skgland]

Ok, I assumed based on the parsing of PackageIdSpec at https://docs.rs/cargo-util-schemas/latest/src/cargo_util_schemas/core/package_id_spec.rs.html#125 and the test at https://docs.rs/cargo-util-schemas/latest/src/cargo_util_schemas/core/package_id_spec.rs.html#425