SequelizeMock as a drop-in replacement

[fantactuka]

I'm trying to use sequelize-mock as a drop-in replacement of regular sequelize. Following snippet is from models/index.js that is using either sequelize-mock or sequelize based on environment

const Sequelize = isTest ? require('sequelize-mock') : require('sequelize');
const sequelize = new Sequelize(dbConfig);

loadFiles(modelsDir).forEach(file => {
  const model = sequelize.import(file);
  db[model.name] = model;
});

db.sequelize = sequelize;
db.Sequelize = Sequelize;

module.exports = db;

All works great except that Sequelize.define from sequelize-mock behaves different. It using its second argument as columns default values, while the one from sequelize using second argument as columns configuration. So given model's code is

Sequelize.define('Class', {
 name: {
   type: Sequelize.STRING,
   field: 'class_name'
 },
 ...
});

then sequelize-mock will be using { type: Sequelize.STRING, field: 'class_name' } as a default value for name column.

Question: Is it something that never supposed to work this way or am I missing something?

P.S. Since apart from that it works for me I've overridden define method to reset _defaults field that there're no default values for columns:

const { define } = SequelizeMock.prototype;
SequelizeMock.prototype.define = (...args) => {
  const model = define(...args);
  model._defaults = {}; // or going through model attributes and using `defaultValue` if it exists
  return model;
};