Improvement: print worlds to choose from in the error message for multi-world packages

[tschneidereit]

When trying to create bindings for a package with multiple worlds, one has to choose which world to target. It'd be great if the error message printed when no choice has been made would print the available options, and ideally also what the option name is for choosing them.

[primoly]

I extended the error message in: bytecodealliance/wasm-tools#1654. This does not fully address the issue about the specific cli option, since this is wit-bindgen specific. This would have to go here:

wit-bindgen/src/bin/wit-bindgen.rs

Line 185 in 749bacc

let world = resolve.select_world(&pkgs, opts.world.as_deref())?;

I don’t know how to best go about this since the select_world method returns an error for other reasons as well.