Next.js 12 introduced next/jest, an experimental jest transformer that integrates swc/jest with little config. Problems can be added to the respective discussion.
This repo is here to reproduce some issues.
As some others reported, next/jest has problems with Jest's mocking.
In addition, I found no way to temporarily delete the window object to simulate an SSR environment. Admittedly, it does require a decent amount of gymnastics to get working in the first place. Handy non the less.
There are different ways to set window to undefined. None worked. Be it deleting it, nor messing with jests mocking.
Changing Jest's environment to node using docblocks also doesn't solve our problems.
# install
yarn
# run tests
yarn testThree commits on total.
- setup
jest/swc(broken)babel-jest(works)
Check out commit #2 or #3 to verify.