isValid virtual generates a crash when updating a nested property

[BobBatard]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Mongoose version

6.4.4

Node.js version

16.15.0

MongoDB server version

5.0.0

Description

Adding a virtual named isValid to a schema which have a nested property and updating the property while setting a value to the virtual generates a crash on save.

Steps to Reproduce

Here's a reproduction script

import mongoose from 'mongoose'
import assert from 'node:assert'


(async () => {
  await mongoose.connect('mongodb://localhost:27017/test', {
    useNewUrlParser: true,
    useUnifiedTopology: true
  })

  await mongoose.connection.dropDatabase()

  const Schema = new mongoose.Schema({
    test: String,
    data: { sub: String }
  })

  Schema.virtual('isValid')

  const testSchema = mongoose.model('Test', Schema)

  await testSchema.create({})
  const doc = await testSchema.findOne()

  doc.set('isValid', true)

  // working
  doc.set({ test: 'test' })
  await doc.save()
  assert.equal(doc.test, 'test')

  // not working
  doc.set({ data: { sub: 'sub' } })
  await doc.save()
  assert.equal(doc.data.sub, 'sub')

  console.log('done')
})()

which throws this error

/node_modules/mongoose/lib/document.js:2761
      if (!_this.$isValid(path)) {
                 ^

TypeError: _this.$isValid is not a function
    at /node_modules/mongoose/lib/document.js:2761:18
    at processTicksAndRejections (node:internal/process/task_queues:78:11)

The script does not crash if

• the virtual is removed
• the virtual is not set
• doc.data.sub is not set

Expected Behavior

It should not crash, or throw a warning on schema creation if isValid should be considered as a reserved keyword.