Populate query with match returns null

Question

I have three schemas, that need them to be separated and I can't use subdocuments. The important one is this

export var TestSchema = new mongoose.Schema({
    hash: { type: String, index: { unique: true }, default: common.randomHash },
    date: { type: Date, default: Date.now },
    result: { type: Object },
    user: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
    data: { type: Object },
    finished: Date,
    lang: { type: String, default: 'pt' },
    benchmark: { type: String, required: true },
    order: { type: mongoose.Schema.Types.ObjectId, ref: 'Transaction' },
    /* TODO: remove */
    name: { type: String } 
});

I have a query that does the populate (it's actually a pagination helper, but I'm cutting to the chase):

TestModel.find({hide: {$ne: true}, user: id}).populate({
   path: 'user', 
   match: {$or: [
     {email: new RegExp(search, i)},
     {name: new RegExp(search, i)}, 
     {empresa: new RegExp(search, i)},
   ]}
}).exec().then(/*...*/)

when populate.match doesn't find anything, it sets the user to null. I tried setting the find({'user':{$ne: null}}) but it ignores it. (I guess the populate happen after the find call, maybe that's the reason).

Is there any way I can filter it in the database layer instead having to rely on iterating of the results, check for null then filter out?

Answer 1

This answer on GitHub clarifies that it is not possible with populate, due to how MongoDB works. However, you should be able to do it with $lookup.