Incorrect ESM types

[petertonysmith94]

As part of #1776, we fixed the runtime issues that were being thrown for ESM based packages. However, the side note of incorrect types as specified by AreTheTypeWrong.

• Masquerading as CJS

[petertonysmith94]

Pretty good resource on ESM related requirements

[danielbate]

I went down a bit of an ESM rabbit hole earlier with #2567 so I'll have a dig here...

[danielbate]

Just done a new check on arethetypeswrong and we have resolved some problems, only the masqueraded ESM now so going to update the description.

[petertonysmith94]

There is a CLI utility for testing the packages locally.

I think the following PR might be helpful.

I wouldn't linger too long upon this one, as no end-consumers have brought this up and I remember this one being a rabbit hole :)

Currently

From what I remember - the issue with our distribution is that we share the types between both ESM and CJS:

└─ dist
    ├── index.d.ts
    ├── index.d.ts.map
    ├── index.js
    ├── index.js.map
    ├── index.mjs
    └── index.mjs.map

Expected

So then the types aren't shared between them.

└─ dist
    ├─ cjs
        ├─ index.d.ts
        ├─ index.d.ts.map
        ├─ index.cjs
        └─ index.cjs.map
    └─ mjs
        ├─ index.d.ts
        ├─ index.d.ts.map
        ├─ index.mjs
        └─ index.mjs.map

[danielbate]

Ty, I will check those out, I think I am reading something similar. But agreed, I won't lose too much time on it.

[danielbate]

Okay so for this as @petertonysmith94 mentions we need to separate our distribution files between CJS and ESM. The expected way for this though is to create a *.d.mts file for ESM typings. Using a single dist seems to be a common problem for projects shipping using tsup. There's a couple open issues right now for tsup to provide more config around dist files for ESM. I think we keep an eye on these issues (1, 2) to see how things develop and me may be able to fix this through tsup. But shipping both CJS and ESM from a single package seems like a very prevalent issue in the TS lib world.

I'm going to close this for now as we haven't had any reports since #1776 and our AreTheTypeWrong report has improved since then. We only have the masqueraded types issue, which seems more nuanced and up for discussion.