File couldn't be moved to "tmp"

On the iOS simulator I get the error: `foo.jpg couldn't be moved to "tmp" because either the former doesn't exist or the folder containing the latter doesn't exist.`

I'm using the image picker to get the the `uri` on an Expo RN project.

My code that fails:

```javascript
// Move file to temp file path
const dest = `${RNFS.TemporaryDirectoryPath}/${uuid}.mp4`;
try {
await RNFS.moveFile(uri, dest);
} catch (e) {
console.error(e.message);
}
```

My package.json:

```
"react": "16.3.0-alpha.1",
"react-native": "https://github.com/expo/react-native/archive/sdk-26.0.0.tar.gz",
"expo": "^26.0.0",
"react-native-fs": "^2.9.11",
```

Any ideas?