Reusing schema with discriminated field fails with "discriminator already exists" error

[ZachLeviPixel]

Prerequisites

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

Mongoose version

7.6.7

Node.js version

18.16

MongoDB server version

6.0.5

Typescript version (if applicable)

No response

Description

I am not sure I caught the minimal scenario where this issue occurs, but it seems that reusing a schema object that contains a discriminated field causes an error. Defining an exact duplicate of the schema does not cause this error.

Steps to Reproduce

'use strict';

const mongoose = require('mongoose');
const { Schema } = mongoose;

const discriminated = new Schema({
    type: { type: Number, required: true },
}, { discriminatorKey: "type" });

discriminated.discriminator(1, new Schema({}));
discriminated.discriminator(3, new Schema({}));

const containerSchema = new Schema({items: [discriminated]});
const containerModel = mongoose.model("container", containerSchema);
//const containerModel2 = mongoose.model("container2", new Schema({items: [discriminated]})); // Works
const containerModel2 = mongoose.model("container2", containerSchema); // Error: Discriminator with name "1" already exists
//const containerModel3 = mongoose.model("container3", new Schema({moreItems: [containerSchema]})); // Error: Discriminator with name "1" already exists

Expected Behavior

Code should run without errors.