3 ms·

Many other languages have similar easy ways of running tests on file changes. For example, in (Node)JS, you can just do `npx jest -o` if you are using Jest tes

Many other languages have similar easy ways of running tests on file changes. For example, in (Node)JS, you can just do `npx jest -o` if you are using Jest testing library, and with Scala you would usually use `~ test` in sbt shell.

stmblast 3y ago
This is likely just a me problem, but I always found Jest extremely annoying to set up with React and TypeScript - particularly with attempting to follow the documentation for jest and then failing spectacularly (in spite of using React Testing Library, jsdom + jest). Cypress on the other hand I found to be really, really good
- pcthrowaway 3y ago
  Cypress and Jest aren't really operating at the same level though. Cypress competes more with Playwright (functional, E2E tests), and Jest competes more with Vitest, Chai, Mocha, Jasmine for unit tests (though it can also do much more). Personally I prefer Vitest to Jest... if it will work for the codebase I'm in.
- brainbag 3y ago
  vitest, like everything to do with vite, just works. The API is almost identical to Jest so you can swap over easily.
riquito 3y ago
That's not the same thing, I think he's referring to the fact that in Rust you can keep unit tests and code in the same file, and strip them away at build time. That's not a thing in the js world (and most other languages), where tests must be in a different file and you are forced to export functions to test them, even if you wanted to keep them private in that file.
norman784 3y ago
To be honest you might be able to use just the built in node test runner (deno and bun also have their own test runners), but IMHO are not as ergonomic as Rust, in Rust you can test private functions in the same file, and that let's you prototype faster, you write a simple function and a test (even when the prototype is not fully functional). In JS land you could do the same I think, but you would need to export all methods that you want to test and they are in other files, and to make things worse you need to setup Typescript to make your IDE more useful and also write less tests, I would argue that in that case vite/vitest will be more helpful because the tests runs with the same config as the bundler, but still, it does not work out of the box as Rust, there might be other languages that have also good ergonomics as Rust in that regard, but none of the languages that I use besides Rust do that.

stmblast 3y ago

This is likely just a me problem, but I always found Jest extremely annoying to set up with React and TypeScript - particularly with attempting to follow the documentation for jest and then failing spectacularly (in spite of using React Testing Library, jsdom + jest). Cypress on the other hand I found to be really, really good

pcthrowaway 3y ago
Cypress and Jest aren't really operating at the same level though. Cypress competes more with Playwright (functional, E2E tests), and Jest competes more with Vitest, Chai, Mocha, Jasmine for unit tests (though it can also do much more). Personally I prefer Vitest to Jest... if it will work for the codebase I'm in.
brainbag 3y ago
vitest, like everything to do with vite, just works. The API is almost identical to Jest so you can swap over easily.

riquito 3y ago

That's not the same thing, I think he's referring to the fact that in Rust you can keep unit tests and code in the same file, and strip them away at build time. That's not a thing in the js world (and most other languages), where tests must be in a different file and you are forced to export functions to test them, even if you wanted to keep them private in that file.

norman784 3y ago

To be honest you might be able to use just the built in node test runner (deno and bun also have their own test runners), but IMHO are not as ergonomic as Rust, in Rust you can test private functions in the same file, and that let's you prototype faster, you write a simple function and a test (even when the prototype is not fully functional). In JS land you could do the same I think, but you would need to export all methods that you want to test and they are in other files, and to make things worse you need to setup Typescript to make your IDE more useful and also write less tests, I would argue that in that case vite/vitest will be more helpful because the tests runs with the same config as the bundler, but still, it does not work out of the box as Rust, there might be other languages that have also good ergonomics as Rust in that regard, but none of the languages that I use besides Rust do that.