Zanie Blue

> Should you have an enum for version? Where the display of the Version::Root is the empty string? Hm interesting I hadn't considered that. Then we'd end often up with...

https://github.com/pubgrub-rs/pubgrub/tree/RPITIT is proving helpful for this — that's what I used in our prototypes to produce the "ideal" message.

We shouldn't be seeing null sets in errors. I'm not sure about the direct dependency conflict thing.

Actually we do show a nullset in this different case: https://github.com/astral-sh/uv/blob/d7cc622d6cf2f53d64abd20bcddcffca41b67c6e/crates/uv/tests/pip_compile.rs#L8796

> Users can implement the "banned list" themselves by simply filtering the versions out before providing them to PubGrub. Although this doesn't provide a way to customize the error message....

Another use-case: We're filtering out package versions that are only available for other platforms (i.e. not published for the current/target platform) but PubGrub cannot be aware of this and consequently...

It turns out cargo-dist [supports aliases](https://opensource.axo.dev/cargo-dist/book/reference/config.html?highlight=alias#bin-aliases)! but I don't think that's actually what we want here, we have more control this way.

I think we'd follow this with some special-casing to the help menu to display `uvx` instead of `uv tool run` when used.

@charliermarsh great question — ideally we'd make this binary teeeenie tiny. I'll investigate that but it sounds like I'll need to duplicate a lot more code?

Mm yeah each of these is going to be large... ``` ❯ ls -lah target/debug/uv target/debug/uvx -rwxr-xr-x 1 zb staff 80M Jun 28 16:53 target/debug/uv -rwxr-xr-x 1 zb staff 80M...