Using Sinon to stub chained Mongoose calls
If you use Promise, you can try sinon-as-promised:
sinon.stub(Mongoose.Model, 'findOne').returns({
exec: sinon.stub().rejects(new Error('pants'))
//exec: sinon.stub(). resolves(yourExepctedValue)
});
Take a look to sinon-mongoose. You can expects chained methods with just a few lines:
sinon.mock(YourModel).expects('findOne')
.chain('where').withArgs('someBooleanProperty')
.chain('exec')
.yields(someError, someResult);
You can find working examples on the repo.
Also, a recommendation: use mock
method instead of stub
, that will check the method really exists.
I've solved it by doing the following:
var mockFindOne = {
where: function () {
return this;
},
equals: function () {
return this;
},
exec: function (callback) {
callback(null, "some fake expected return value");
}
};
sinon.stub(mongoose.Model, "findOne").returns(mockFindOne);
Another way is to stub or spy the prototype functions of the created Query (using sinon):
const mongoose = require('mongoose');
sinon.spy(mongoose.Query.prototype, 'where');
sinon.spy(mongoose.Query.prototype, 'equals');
const query_result = [];
sinon.stub(mongoose.Query.prototype, 'exec').yieldsAsync(null, query_result);