### Is this a bug report? Yes ### Did you try recovering your dependencies? Yes ### Which terms did you search for in User Guide? Troubleshoting section `npm test hangs on macOS Sierra` didn't help me. ### Environment 1. `node -v`: v9.8.0 2. `npm -v`: 5.6.0 3. `yarn --version` (if you use Yarn): 1.5.1 4. `npm ls react-scripts` (if you haven’t ejected): react-scripts@1.1.1 1. Operating system: macOS Sierra 10.13.3 2. Browser and version (if relevant): Google Chrome 64.0.3282.186 ### Steps to Reproduce 1. npx create-react-app demo 2. cd ./demo 3. yarn 4. yarn test (...and all works fine) 5. yarn add antd 6. yarn test (...and there is an error) ### Expected Behavior All must work fine. Because it's nonscence when installing some library have influence to environment.  ### Actual Behavior Got an error: 