Example repo showcasing an issue with debugging in jest.
Run npm install and then run node debug ./node_modules/.bin/jest -i
Look at the Component.js file. There are two debugger statements.
The one in the render method breaks, but the one in the clickHandler doesn't.
However, the code inside the clickHandler runs, because the console.log output is visible.
There's a known issue with this where breakpoints don't break at all: jestjs/jest#1652
In the particular project I'm having this issue in, I'm using sinon's fakeServer which has issues with jsdom on this version of Node. There's also a known issue about this: jsdom/jsdom#1706
In any case, whenever I tried to use this, the browser just disconnects and it doesn't really work, probably due to its still experimental nature.