this.constructor.populate is not a function

[simllll]

report a bug

documen.populate({path: 'jobFilter._type', select: lang}).execPopulate(); fails with:

error TypeError: this.constructor.populate is not a function
    at Document.populate (/home/simon/Dev/Web/hokify-server/node_modules/mongoose/lib/document.js:2462:22)

Just call a document and try to populate something on it. This worked before, broken in latest version though.

node v.8.5.0
mongoose 4.12.1
I'm using bluebird with

const Promise = require('bluebird');
mongoose.Promise = Promise;

any idea what's going on here? has the syntax changed?

[simllll]

I've found the reason for this bug: I'm calling .populate(..).execPopulate() on a sub document.
E.g.
DocumentA

• key1
• key2

What I did was calling DocumentA.key1.populate(...).execPopulate().. this worked before, but does not anymore.

Not sure if this is intended, please just close it if this is correct - but then a better error message would be nice to have, now it just fails with this non saying "is not a function" error.

Thanks for mongoose 👍 !

[vkarpov15]

Thanks for reporting, will investigate. If you can provide a standalone script that reproduces your issue that would be very helpful 👍

[sobafuchs]

I'm not able to reproduce this:

const mongoose = require('mongoose');
mongoose.Promise = global.Promise;

const GITHUB_ISSUE = `gh-5703`;

exec()
  .then(() => {
    console.log('program successful');
    process.exit(0);
  })
  .catch(error => {
    console.error(`Error: ${ error }\n${ error.stack }`);
    process.exit(1);
  });

async function exec() {
  await mongoose.connect(`mongodb://localhost:27017/${ GITHUB_ISSUE }`);

  const toySchema = new mongoose.Schema({
    color: String
  });
  const Toy = mongoose.model('Toy', toySchema);

  const childSchema = new mongoose.Schema({
    toy: { type: mongoose.Schema.Types.ObjectId, ref: 'Toy', required: true }
  });
  const Child = mongoose.model('Child', childSchema);

  const toy = await Toy.create({ color: 'blue' });
  let child = await Child.create({ toy: toy._id });

  child = await Child.findById(child._id);
  await child.populate('toy').execPopulate();
  console.log(`Toy: `, child.toy); // shows { _id: 69e6a6..., color: 'blue', __v: 0 }
}

@simllll can you see if the above script works for you?

[sobafuchs]

@simllll did you have a chance to see if that script works for you?

[simllll]

Sorry for the delay,it's still on my list. As far as I can tell,the script you provided works for me. I will try to build a case similar to my setup that caused the issue. I will let you know when I have more details!

[sobafuchs]

ok thanks

[vkarpov15]

Closing for now, will re-open if additional info is provided

[simllll]

Right, I've found a reproducable code.. but again, I'm not even sure if this is maybe intended. All I know is that this DID work before, but does not anymore. The problem is that I've a model like this:

{
     values: {
            value: String,
            toy: { type: mongoose.Schema.Types.ObjectId, ref: 'Toy'}
     }
}

I've passed the "values" to a sub function that tried to populate "toy" then. It makes somehow sense to me now that this does not work (anymore) as this passed object is actually just a part / "sub mongoose object" and not the mongoose model itself.

see example code to see what I mean:

const mongoose = require('mongoose');
mongoose.Promise = require('bluebird'); // just switched it to bluebird, does not actually matter

const GITHUB_ISSUE = `gh-5703`;

exec()
    .then(() => {
        console.log('program successful');
        process.exit(0);
    })
    .catch(error => {
        console.error(`Error: ${ error }\n${ error.stack }`);
        process.exit(1);
    });

async function exec() {
  await mongoose.connect(`mongodb://localhost:27017/${ GITHUB_ISSUE }`);
   const toySchema = new mongoose.Schema({
        color: String
    });
    const Toy = mongoose.model('Toy', toySchema);

    const childSchema = new mongoose.Schema({
        name: { type: String, select: false},
        values: {
            value: String,
            toy: { type: mongoose.Schema.Types.ObjectId, ref: 'Toy'}
        }
    });
    const Child = mongoose.model('Child', childSchema);

    const toy = await Toy.create({ color: 'blue' });
    let child = await Child.create({ 'values.value': 'hello', 'values.toy': toy._id });

    child = await Child.findById(child._id).select('+name');
    await child.values.populate('toy').execPopulate(); // does not work..
    //await child.populate('values.toy').execPopulate(); // works
    console.log(`Child: `, JSON.stringify(child,false,3));
}

Results in:
Error: TypeError: this.constructor.populate is not a function TypeError: this.constructor.populate is not a function

In case you consider this is a bug, reopen it please @vkarpov15

[vkarpov15]

Ah ok, its because you're calling .populate() on a nested value. Thanks for the repro, will investigate.