“mpromise (mongoose's default promise library) is deprecated” error when testing [duplicate]

Answer 1

From node 4.x you can just use ES6 promises:

const mongoose = require('mongoose');
mongoose.Promise = Promise;

Answer 2

you can refer to How to use mongoose Promise - mongo

the page content :

On this page:http://mongoosejs.com/docs/promises.html

The title is Plugging in your own Promises Library

Answer 3

Here's an example that may help. Using es6 modules (instead of CommonJS require) this works for me:

// mongoose's Promise library is deprecated, using es6's: 
import es6Promise from 'es6-promise';
mongoose.Promise = es6Promise.Promise;

Answer 4

You need to plugin a promise library (q, bluebird, the es6 one...)

mongoose.Promise = require('bluebird');