How to test fable-library-ts ?

[goswinr]

How can I test fable-library-ts ?
By running tsc in its folder?

@MangelMaxime I am picking up on thoth-org/Thoth.Json#217 and #3586

Is it possible that fable-library-ts compiles with tsc only for Node but not for the browser?

For example this line fails to compile because TS doesn't know what Buffer is in a browser context.

Could I manually just edit these fable-library-ts files so that tsc works?

(I found some context here: #3420 )

[MangelMaxime]

That's a good question.

I think there are several solutions:

1. Remove Buffer usage and rely only on TextEncoder and the polyfill

2. When targeting browser specify that people need mark Buffer as external in their bundler (this can perhaps do the trick)

   However, I don't think tsc as a setting for that out of the box

3. Use a global.d.ts file say "I know what I am doing" 😅

   // global.d.ts
   declare const Buffer: any;

Thinking about it and looking at support for TextEncoder API I think we should go with solution 1.

TextEncoder & TextDecoder as 96.34% supports

@ncave What do you think?

[goswinr]

Thanks for looking at this @MangelMaxime and @ncave.
So editing the ts files here would be the right way?
I think we should make sure all of @fable-org/fable-library-ts can be compiled with tsc and a specified tsconfig.json ( currently there are two. at src/fable-library-ts and at src/fable-library-ts/ts . Does such a test exist?
(Bundeling @fable-org/fable-library-ts wih Vite just works in a TS projects because vite skips the checks by default. but tsc not.)

[goswinr]

another option:

// Use globalThis to check for Buffer safely
  const g = globalThis as any;
  if (typeof g.Buffer !== "undefined") {
    const bytes = g.Buffer.from(str, "utf16le");
``

[MangelMaxime]

I think we should make sure all of @fable-org/fable-library-ts can be compiled with tsc and a specified tsconfig.json ( currently there are two. at src/fable-library-ts and at src/fable-library-ts/ts .

This is already happening because fable-library-js is the result of the compiling fable-library-ts with tsc.

However, because we have @types/node installed in the repo it didn't failed the compilation as Buffer is defined from that package.

[ncave]

@MangelMaxime

@ncave What do you think?

I think @goswinr 's workaround is better, we shouldn't be using polyfills if we can avoid it.

[olivercoad]

Is this for testing something different to ./build.sh test typescript? I didn't run into this issue when working on it last week

[goswinr]

@olivercoad yes, when you have @types/node installed the issue does not show. I think there should be a TSC test running without @types/node installed.