fix: override rust type to javascript

[nilslice]

the rust type seems to only have been added as a way to automatically trigger wasm-pack, but it's much better to put that in a custom [build] step instead. eventually, we really should phase out the rust type from wrangler altogether, but this at minimum makes the new rust template work.

[threepointone]

will this break existing projects?

[nilslice]

@threepointone, nope! this only takes affect when calling wrangler generate. all existing type = rust projects remain unaffected.

[threepointone]

But new rust projects won't use wasm-pack? As in, they'll work differently from what they work like before? (Sorry for the noob question, just wondering if this is a breaking change). Rust projects will have to do their own compilation after this, and will behave like a 'javascript' (aka no build) project?

(Long term I agree we should do away with 'type' completely)

[nilslice]

The build for new rust projects uses a "custom build" command, and is not compatible with old-style rust projects. But this change doesn't affect any old projects who still use type = "rust". Those will still be recognized by wrangler build and continue to compile.

With this change, only new projects which are generated with --type rust will have different behavior.

[nilslice]

Rust projects will have to do their own compilation after this, and will behave like a 'javascript' (aka no build) project?

Yes, but in the new template, we provide a new build command that handles the compilation specifically how workers-rs projects need to be built.