react-native-fs DocumentDirectoryPath Where is the catalog on the phone？

https://github.com/itinance/react-native-fs

import RNFS from 'react-native-fs';console.log(RNFS.DocumentDirectoryPath);// /data/data/a.a.a/filesRNFS.writeFile(  RNFS.DocumentDirectoryPath +'/test.txt','Lorem ipsum dolor sit amet','utf8',)  .then(success => console.log('FILE WRITTEN!'))  .catch(err => console.log(err.message));

But this file is not on the phone /Android/data/a.a.a/files/test.txt

Where is this file ?