rescript-schema VS rescript-jest

I have seen something like this in real code, and it led to bugs. ReScript won't allow you to do this, you will have to parse the JSON with a library like rescript-schema (it's like Zod).

Hello, I’m Dmitry Zakharov, a Frontend-engineer at Carla and author of rescript-struct. After using ReScript for two years, of which 9 months are in production, I’ve gotten some insights about testing I wanted to share. I use ReScript not only for FE but for different areas, so if you’re a BE engineer or create a CLI tool, this article will also be useful for you.

Another popular option is to use bindings for Jest. However, in my opinion, Jest is a monstrous combine that is slow, has a hacky mock system, bad ESM support, and purely tries to mimic DOM API with JSDOM. AVA literally doesn't have any of these. Also, the available Jest bindings don't allow doing multiple assertions per test, which is often useful to me.

In order to write tests in ReScript, and thus test your code directly, you can use bs-jest, which provides ReScript bindings to Jest. If you prefer, you can also use the slightly less mature bs-mocha. You can also test the generated JavaScript or TypeScript files with no extra configuration.