Possible Mongo Native Incompatibility

[michaelcox]

In Mongoose 4.0.4 I've found what I think is an incompatibility with the native Mongo driver. This issue is not present in 4.0.1. It appears to only happen if I also install the native mongo driver as a dependency in the project, even though it's not used in the sample code itself.

node version v0.10.37
npm version 1.4.28

I've simplified it down to the following code:

package.json

{
  "dependencies": {
    "mongoose": "4.0.4",
    "mongodb": "2.0.33"
  }
}

index.js

var assert = require('assert');
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var ObjectId = mongoose.Types.ObjectId;
mongoose.connect('mongodb://localhost/mongoose-test');

var Cat = mongoose.model('Cat', {
    name: String,
    bestFriend: {
        type: Schema.Types.ObjectId,
        ref: 'Cat'
    }
});

// Clear all cats
Cat.remove({}, function(err) {
    assert.equal(err, null);

    // Save a new cat
    var kitty = new Cat({ _id: '607f1f77bcf86cd799439012', name: 'Zildjian' });
    kitty.save(function (err) {
        assert.equal(err, null);

        // Save a cat using direct collection insert
        Cat.collection.insert({
            _id: ObjectId('507f1f77bcf86cd799439011'),
            name: 'Zildjian',
            bestFriend: ObjectId('607f1f77bcf86cd799439012')
        }, function (err) {
            assert.equal(err, null);

            // Asert that cat was saved correctly
            Cat.findById('507f1f77bcf86cd799439011', function(err, cat) {
                assert.equal(err, null);
                assert.equal(typeof cat.bestFriend, 'object'); // This fails

                process.exit(0);
            });

        });

    });

});

In the above code assert.equal(typeof cat.bestFriend, 'object'); will fail with AssertionError: "undefined" == "object". It appears for some reason it doesn't want to save that value.

[vkarpov15]

This is a duplicate of #3020 etc. Will be fixed for next release.