Validate doesn't work with conditional required fields

Do you want to request a feature or report a bug? Bug.

What is the current behavior? Conditional required fields don’t throw when using Model.validate().

If the current behavior is a bug, please provide the steps to reproduce.

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

run().catch(console.error);

async function run () {
  const userSchema = new mongoose.Schema({
    name: { type: String, required: true },
    age: { type: Number, required () {return this.name === 'John';} }
  });

  const User = mongoose.model('User', userSchema);

  const err = await User.validate({ name: 'John' }).then(() => null, err => err);
  assert.ok(err);
}

What is the expected behavior? Expects method to throw a validaiton error path age is requried.

What are the versions of Node.js, Mongoose and MongoDB you are using? Note that “latest” is not a version. Node.js: 14.15.5 Mongoose: 5.12.13 MongoDB: 4.4.3

[vkarpov15]

@AbdelrahmanHafez I agree, let’s discuss in your PR #10360

[IslandRhythms]

Ok so the problem is the this object. As a result, when you call User.validate, you need to include the other two parameters in that call. Set the 2nd parameter to null and the third parameter the same as the first, so for expediency’s sake you could create a variable and save it as that. more here

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

run().catch(console.error);

async function run () {
    await mongoose.connect('mongodb://localhost:27017/test', {
        useNewUrlParser: true,
        useUnifiedTopology: true
    })
    await mongoose.connection.dropDatabase();
  const userSchema = new mongoose.Schema({
    name: { type: String, required: true },
    age: { type: Number, required () {return this.name === 'John';} }
  });

  const User = mongoose.model('User', userSchema);
  const obj = {name: 'John'};

  const err = await User.validate(obj, null, obj).then(() => null, err => err);
  console.log('hi', err);
  assert.ok(err);
}