model.test.js

  'pushing to an array of Mixed works': function () {
    var db = start();

    mongoose.model('MySchema_', new Schema({
      arrays: []
    }));

    var DooDad = db.model('MySchema_')
      , doodad = new DooDad({ arrays: [] })
      , date = 1234567890;

    doodad.arrays.push(["+10", "yup", date]);

    doodad.save(function (err) {
      should.strictEqual(err, null);

      DooDad.findById(doodad._id, function (err, doodad) {
        should.strictEqual(err, null);

        doodad.arrays.toObject().should.eql([['+10','yup',date]]);

        doodad.arrays.push(["another", 1]);

        doodad.save(function (err) {
          should.strictEqual(err, null);

          DooDad.findById(doodad._id, function (err, doodad) {
            should.strictEqual(err, null);

            doodad
            .arrays
            .toObject()
            .should.eql([['+10','yup',date], ["another", 1]]);

            db.close();
          });
        });
      })
    });

  },