Not working for typescript

[theKashey]

Actually the problem is not with typescript - the problem is with rollup.

https://unpkg.com/memoize-one@4.0.2/dist/memoize-one.cjs.js contains

module.exports = index;

which should be imported as import * as memoizeOne

while https://unpkg.com/memoize-one@4.0.2/dist/memoize-one.esm.js contains

export default index;

which should be imported as import memoizeOne

Result - the code for nodejs (~jest) require one behaviour, while the code for webpack(uses esm bundle) requires another.

It is not a problem for js/flow, as long babel is doing some around magic default imports, but typescript is quite strict about it.

The cjs bundle should match esm bundle.

(and fixing this would introduce a breaking change)

[alexreardon]

@TrySound thoughts?

[alexreardon]

As you mentioned @theKashey we are using rollup to generate the bundles. It sounds like there is an issue with the cjs bundle. Is there an option we can change for the rollup build...?

[TrySound]

This is the old issue with typescript itself and default exports. My solution is getting rid from default exports in the next major release. They are quite useless.

I'm not alone.
jaredpalmer/formik#973 (comment)

[TrySound]

@theKashey cjs bundle is matched to esm bundle by the way, it's typescript fault.

[MrKWatkins]

I've added the following function as a workaround which I call at the start of my tests:

export function ensureMemoizeOneInitialized()
{
    if (typeof memoize === "undefined")
    {
        /* tslint:disable:no-var-requires */
        (memoize as any) = require("memoize-one");
    }
}

[alexreardon]

I would be keen to find a way forward in our generated code. Ideally it would work with TS out of the box. Any thoughts @TrySound?

[TrySound]

This is the best and not only for typescript
https://basarat.gitbooks.io/typescript/docs/tips/defaultIsBad.html

[TrySound]

Actually there is esModuleInterop flag which fixes this behaviour in typescript similar to "magical" (it's not) babel way.

[TrySound]

It should be default since v3 but "TS has such big ecosystem".

[alexreardon]

Could you make a PR? 🤘

…

On Mon, 22 Oct 2018 at 6:27 pm, Bogdan Chadkin ***@***.***> wrote: It should be default since v3 but "TS has such big ecosystem". — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#37 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ACFN7RU3hwk_4gHF4hKLyNKm9gx3Cr9rks5unXNKgaJpZM4XT298> .

[TrySound]

To typescript? I'm not. Users should enable it and fix all modules in DefinitelyTyped.

[TrySound]

Or do you mean named export?

[theKashey]

Please don't use esModuleInterop or allowSyntheticDefaultImports, it will require target consumer to set it, and this is something you shall not ask for.
PS: And also affects imports, not exports.

[TrySound]

@theKashey That's the point. It should be default. Ecosystem is broken now. It's just doesn't work for many packages.

[alexreardon]

To typescript? I'm not. Users should enable it and fix all modules in DefinitelyTyped.

@TrySound I misunderstood you. I thought we could add a simple rollup plugin and be done with this issue

It sounds like you have some insight into this @theKashey, any thoughts on how to proceed?