rescript-react VS rescript-jest

Another cool example is that this also works for React component props (ReScript has first class support for React and JSX!).

ReScript (before BuckleScript) https://rescript-lang.org/ is a functional language that can also use OOP. Ideal for Javascript and Typescript projects, React and servers. It integrates perfectly with Javascript and Typescript code https://rescript-lang.org/docs/react/latest/introduction

@rescript/react: ReScript bindings to React and support for JSX

@rescript/react comes with a router already so we don't need to install anything else to get started. Here are the full docs, but let's walk through each step in detail to make sure we understand it.

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.