jco exports uses invalid alias based on WIT world package name

[DougAnderson444]

Hi, it's me again

Given the following WIT that exports an interface named reactivity:

package wurbo:vowels;

interface reactivity {
  render: func(name: string) -> string;
  listen: func();
}

world example {
    import imports;
    export reactivity;
}

the resulting ES module code is invalid because the world package name is also used:

// ... 

await $init;
const reactivity = {
  listen: listen,
  render: render,
  
};

export { reactivity, reactivity as wurbo:vowels/reactivity };
//                                  ^^^^^^^^^^^^^^^^^^^______invalid javascript

The : is invalid JS syntax unfortunately

[DougAnderson444]

The workaround is to not use export interfaces, but it's probably better to just remove the invalid alias?

[guybedford]

export { reactivity, reactivity as "wurbo:vowels/reactivity" }; is very much valid JavaScript, I'm pretty sure you'll find it's quoted.

The problem is that TypeScript doesn't support the above. We have a flag for supporting this via --no-namespaced-exports, at least until TypeScript adds support in microsoft/TypeScript#40594.

[DougAnderson444]

No Typescript was involved at all in this process. The export was definitely not in "quotes" in my code, I wonder if Rollup removed it during the bundling process? I will try the flag and see what happens, thank you

[DougAnderson444]

Tried the flag and it works nicely thank you Guy.

You were right, jco outputs the export in quotes and Rollup is removing them when bundling the files together. Looks like this is an issue with Rollup not jco! Yeah!

I'll close and shift this to Rollup

[guybedford]

Thanks for following up on the Rollup issue here!

[DougAnderson444]

This issue has been resolved via rollup/rollup#5298 as part of [email protected].

[James-Mart]

The problem is that TypeScript doesn't support the above. We have a flag for supporting this via --no-namespaced-exports, at least until TypeScript adds support in microsoft/TypeScript#40594.

FYI microsoft/TypeScript#58640
CC @guybedford