npm test doesn't find files in CRA3

[TomasHubelbauer]

I have run into an issue where npm test which works perfectly with current stable CRA doesn't work with CRA3 if the testing instructions in the docs are followed.

I have created a repro showcasing this deterministically, just run npm test in it.

The steps to reproduce are:

1. npm create-react-app . --typescript
2. npm install --save enzyme enzyme-adapter-react-16 react-test-renderer
3. npm install --save-dev @types/enzyme @types/enzyme-adapter-react-16
4. setupTests.ts as per https://facebook.github.io/create-react-app/docs/running-tests#src-setuptestsjs
5. npm test still works!
6. npm install react-scripts@3.0.0-next.b0cbf2ca Roadmap for version 3.0 #6475
7. npm test now says it cannot find any files! App.test.tsx sits right there.

Now sure if this is caused by TypeScript or not, I have not tried to see if this reproduces with the JavaScript version of CRA3.

[ianschmitz]

Sounds like #6313 will solve your problem. Can you confirm?