neverMarkModified.js

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var assert = require('assert')

console.log('\n===========');
console.log('    mongoose version: %s', mongoose.version);
console.log('========\n\n');

var dbname = 'testing_neverMarkModified';
console.log('dbname: %s', dbname);
mongoose.connect('localhost', dbname);
mongoose.connection.on('error', function () {
  console.error('connection error', arguments);
});

var schema = new Schema({
    _name: String
});

schema.virtual('name').set(function (v) {
  console.log('ignoring', v);
}).get(function () {
  return this._name;
});

schema.pre('save', function (next) {
  this.set('_name', 'set from pre-save only');
  next();
})

var A = mongoose.model('A', schema);

mongoose.connection.on('open', function () {
  var a = new A({ name: 'neverMarkModified' });
  console.log(a);
  a.name = 'trying to set directly';
  console.log('name is %s', a.name);

  a.save(function (err, a) {
    if (err) return done(err);
    console.log('name is %s', a.name);

    A.findById(a, function (err, doc) {
      console.error('found', doc);
      done(err);
    });
  })
});

function done (err) {
  if (err) console.error(err.stack);
  mongoose.connection.db.dropDatabase(function () {
    mongoose.connection.close();
  });
}