model-hasMany-error.js

var
    // $ npm install model@0.2.10
    model = require( 'model'),
    Adapter = require('./node_modules/model/lib/adapters/memory/').Adapter,
    adapter = new Adapter({})

var User = function () {
    this.adapter = adapter;
    this.property('login', 'string', {required: true});
    this.property('password', 'string', {required: true});
    this.property('confirmPassword', 'string', {required: true});

    this.hasMany('Accounts');
};
User = model.register( 'User', User );

var Account = function() {
    this.adapter = adapter;
};
Account = model.register( 'Account', Account );

var user = User.create({
    login: 'asdf'
    , password: 'zerb'
    , confirmPassword: 'zerb'
});
user.save(function (err, data) {
    if (err) {
        throw err;
    }
    user.addAccount(Account.create({}));
    user.addAccount(Account.create({}));
    user.save(function (err, data) {
        if (err) {
            throw err;
        }
        user.getAccounts(function (err, data) {
            if (err) {
                throw err;
            }
            console.log('This number should be 2: ' + data.length);
        });
    });
});

// Its throw that error:
//
// .../node_modules/model/lib/query/query.js:184
//          datatype = descr.datatype;
//                          ^
// TypeError: Cannot read property 'datatype' of undefined