When i start my app with command npm start all ok, but when i build my app with command npm run build i get error 

```
13 verbose stack Error: test@0.1.0 build: `react-scripts build`
13 verbose stack Exit status 1
13 verbose stack     at EventEmitter.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/index.js:304:16)
13 verbose stack     at emitTwo (events.js:126:13)
13 verbose stack     at EventEmitter.emit (events.js:214:7)
13 verbose stack     at ChildProcess.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/lib/spawn.js:55:14)
13 verbose stack     at emitTwo (events.js:126:13)
13 verbose stack     at ChildProcess.emit (events.js:214:7)
13 verbose stack     at maybeClose (internal/child_process.js:925:16)
13 verbose stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:209:5)

```

What can be wrong?

**EDIT**
I create my app using command create-react-app myapp.
Index.js look like

```
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import registerServiceWorker from './registerServiceWorker';
import 'bootstrap/dist/css/bootstrap.css';
import {BrowserRouter} from 'react-router-dom';
ReactDOM.render(
    <BrowserRouter>
        <App/>
    </BrowserRouter>
    , document.getElementById('app'));
registerServiceWorker();

```

And package.json

```
{
"name": "mailsender-client",
"version": "0.1.0",
"private": true,
"dependencies": {
"bootstrap": "^4.1.3",
"jquery": "^3.3.1",
"moment": "^2.22.2",
"query-string": "^6.5.2",
"react": "^16.4.1",
"react-dom": "^16.4.1",
"react-router": "^3.2.1",
"react-router-dom": "^4.3.1",
"react-scripts": "1.1.4"
},
"scripts": {
 "start": "react-scripts start",
 "build": "react-scripts build",
"test": "react-scripts test --env=jsdom",
"eject": "react-scripts eject"
}
}

```