Move uvx shell completion to uvx --generate-shell-completion

[bluss]

Summary

Because a problem was found with Powershell and combining the generated completion scripts for uv and uvx, let's try separating uv and uvx command completion scripts.

The generated powershell script template can be seen in clap_complete source, and it starts with using directives, which makes it impossible (apparently) to concatenate two of those script outputs.

As a side effect, this is available under uv tool run --generate-shell-completion too.

Fixes #7482

Test Plan

• eval "$(cargo run --bin uvx -- --generate-shell-completion bash)"
• Test Powershell

[bluss]

Link to the powershell generator template - https://docs.rs/clap_complete/4.5.28/src/clap_complete/aot/shells/powershell.rs.html#28 - IMO we should not try to patch the output of the generator, but it seems to be possible, feel free to go that route if you want to.

[bluss]

Cc @ilyagr if you are interested

[charliermarsh]

Why am I hitting this? 🤔

❯ cargo run --bin uvx -- --generate-shell-completion
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.15s
     Running `target/debug/uvx --generate-shell-completion`
error: unexpected argument '--generate-shell-completion' found

Usage: uvx [OPTIONS] [COMMAND]

For more information, try '--help'.

[charliermarsh]

Oh I think I had to build uv too.

[charliermarsh]

Thanks for following up.