如何解决UnhandledPromiseRejectionWarning：ValidationError？

Question

I tested all solutions I found on Stackoverflow associated with mongoose error.

Anyways, I am facing a problem with the below piece of code. I think the problem is in something else, but I can't find it.

I have other files linked with this one.

.finally catch ( it resolves part of the error)

const assert = require('assert');
const User = require('../src/users');

describe('Test de virtualType', () => {

    it("Test que le virtualType retourne bien le nombre de livre de l'utilisateur", (done) => {
    const user1 = new User({
        userName: 'Robin',
         shopslist: [{ shopName: 'Le seigneur des anneaux' },{articleName:'Les raisins de la colère'}]
    });

    user1.save()
      .then(() => User.findOne({ userName: 'Robin' }))

      .then((User) => {
        assert(user1.countShops.length===2);
      }) 
      .finally(done);

     });


});

Terminal indicates :

(node:19900) UnhandledPromiseRejectionWarning: ValidationError: user validation failed: shopslist.0.articleName: L'articleName est requis, shopslist.1.shopName: Le shopName est requis
    at new ValidationError 
    at process._tickCallback (internal/process/next_tick.js:61:11)
(node:19900) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 9)```

Answer 1

UnhandledPromiseRejectionWarning - You should handle error by using resolve() and reject() when you get a promise via .save() method for User .Then you can use:

 const user1 = new User(...);

 user1.save()
.then(done =>{ //Do stuff here })
.catch(error =>{ console.log(error); })