I'm trying create-react-app for testing but can't get it to work.

```
npx create-react-app tester
cd tester
yarn
yarn test

```

OUTPUT:

```
yarn run v1.13.0
$ react-scripts test
Done in 0.59s.
terry@terry-sharewalker:~/myProjects/tester$ 

```

I thought I read that CRA starts in "watch mode", but it just jumps back to my cursor. Isn't is supposed to run something? I see a test in the src/ folder called App.test.js. But is it running? How can I test that the test is running?

EDIT -- HERE'S MY ENVIRONMENT INFO:

npx create-react-app testing --info
npx: installed 63 in 11.717s

Environment Info:

System:
 OS: Linux 4.15 Ubuntu 16.04.5 LTS (Xenial Xerus)
 CPU: x64 Intel(R) Core(TM) i5-4210M CPU @ 2.60GHz
 Binaries:
 Node: 10.15.3 - ~/.nvm/versions/node/v10.15.3/bin/node
 Yarn: 1.13.0 - ~/.nvm/versions/node/v10.15.3/bin/yarn
 npm: 6.9.0 - ~/.nvm/versions/node/v10.15.3/bin/npm
 Browsers:
 Chrome: 68.0.3440.106
 Firefox: 64.0
 npmPackages:
 react: Not Found
 react-dom: Not Found
 react-scripts: Not Found
 npmGlobalPackages:
 create-react-app: Not Found