[BUG] [5.12.7] Cannot create property '$isUnderneathDocArray' on string 'nested'

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

What is the current behavior? Cannot create property '$isUnderneathDocArray' on string 'nested'

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

run this script:

const { Schema } = require('mongoose')

const DynamicTextMatchFeaturesSchema = new Schema({
  css: { color: String },
})

const PossibleElementsArraySchema = {
  type: [
    {
      textMatchFeatures: {
        dynamic: { type: DynamicTextMatchFeaturesSchema },
      },
    },
  ],
}

const ElementSchema = new Schema({ image: { type: String } })

const possibleElementsStrategy = {
  possibleElements: PossibleElementsArraySchema,
}

ElementSchema.add(possibleElementsStrategy)

What is the expected behavior?

To not print this message

What are the versions of Node.js, Mongoose and MongoDB you are using? Note that “latest” is not a version. Node 14.15.1 Mongoose 5.12.7 it is working fine with 5.12.5 but not 5.12.7

[Jule-]

I can confirm too.

[gilles-yvetot]

@IslandRhythms you don’t even need to actually connect to a database for the bug to occur