Inheritance via discriminator, hooks are not inherited, contrary to the documentation

[qqilihq]

Mongoose 4.9.3

I use schema inheritance, as described here. Samle code:

var options = {discriminatorKey: 'kind'};

var eventSchema = new mongoose.Schema({time: Date}, options);
eventSchema.pre('findOneAndUpdate', function() {
  console.log('eventSchema: findOneAndUpdate');
});
var Event = mongoose.model('Event', eventSchema);

var clickedEventSchema = new mongoose.Schema({url: String}, options)
clickedEventSchema.pre('findOneAndUpdate', function() {
  console.log('clickedEventSchema: findOneAndUpdate');
});
var ClickedLinkEvent = Event.discriminator('ClickedLink', clickedEventSchema);


mongoose.connect('mongodb://localhost:27017/test');

ClickedLinkEvent.findOneAndUpdate(
  { url: 'example.com' },
  { time: new Date() },
  { new: true, upsert: true },
  function(err, result) {
    console.log(err || result);
  }
);

eventSchema and clickedEventSchema each have their findOneAndUpdate hook.

UponfindOneAndUpdate, only the clickedEventSchema's hook is executed:

clickedEventSchema: findOneAndUpdate

This is contrary to what the documentation states:

Discriminators also take their base schema's pre and post middleware. However, you can also attach middleware to the discriminator schema without affecting the base schema.

Bug? Outdated documentation? Misunderstanding?

[sobafuchs]

yeah this looks like a bug, thanks for reporting. Here's a full repro script to recreate:

const mongoose = require('mongoose');
const co = require('co');

mongoose.Promise = global.Promise;

const GITHUB_ISSUE = `gh-5147`;

exec()
  .then(() => {
    console.log('program ran successfully');
    process.exit(0);
  })
  .catch(error => {
    console.error(`Error: ${error}\n${error.stack}`);
    process.exit(2);
  });

function exec() {
  return co(function* () {
    const db = mongoose.connect(`mongodb://localhost:27017/${GITHUB_ISSUE}`);
    var options = { discriminatorKey: 'kind' };

    var eventSchema = new mongoose.Schema({ time: Date }, options);
    eventSchema.pre('findOneAndUpdate', function() {
      console.log('eventSchema: findOneAndUpdate'); // does not run
    });

    var Event = db.model('Event', eventSchema);

    var clickedEventSchema = new mongoose.Schema({ url: String }, options)
    clickedEventSchema.pre('findOneAndUpdate', function() {
      console.log('clickedEventSchema: findOneAndUpdate');
    });
    var ClickedLinkEvent = Event.discriminator('ClickedLink', clickedEventSchema);

    yield ClickedLinkEvent.remove({});
    const result = yield ClickedLinkEvent.findOneAndUpdate(
      { url: 'example.com' },
      { time: new Date() },
      { new: true, upsert: true });

    console.log('result', result);
  });
}