Realm object constructor must not return another value

Goals

Hi, my goal is to use ES6 Classes and inheritance as Realm models. This possibly relates to https://github.com/realm/realm-js/issues/2768 After upgrading realm and react-native from

"realm": "2.23.0",
"react": "16.0.0",
"react-native": "0.50.3",

the following error shows up Realm object constructor must not return another value

I was wondering if there is any way to get this to work with later versions

https://github.com/realm/realm-js/issues/2768#issuecomment-604438625 This mentions that we shouldn’t extend Realm.Object but doesn’t say anything else about extending other classes. https://realm.io/docs/javascript/latest/#classes The docs don’t mention anything about this either.

Code Sample

class BaseModel {}
 
export class Account extends BaseModel {
  static schema = {
    name: 'Account',
    primaryKey: 'uuid',
    properties: {
      uuid: 'string',
      id: {type: 'int', indexed: true},
      firstName: 'string',
      lastName: 'string',
      username: 'string',
      apiKey: 'string',
      lastLogin: 'date'
    },
  };
}

database = new Realm({
      path: 'core.realm',
      schema: [
        Account, // eslint-disable-line no-use-before-define
        // ...
      ],
      schemaVersion: 13,
      migration: () => null,
    });

Similar to https://github.com/realm/realm-js/issues/2768 the error goes away when removing the extends

Version of Realm and Tooling

"realm": "^3.6.5",
"react": "^16.13.1",
"react-native": "0.62.0",
node v10.14.2
macOS Catalina 10.15.4

I also tried 5.0.2 and 4.0.0-beta.2 and got the same error

[blagoev]

We have a bug in the RN debugging infrastructure for v5 and we are working to fixing this.

[aqos156]

This error seems to be still happening in 10.3.0 - we have just migrated our code to be compatible with the version 10.x.x from 3.x.x and are facing this issue. If we do not use a debugger (RN Debugger, Google Chrome debugger) it works as expected.

Model

export class User extends Realm.Object {
  static REGISTERED: number = 0;
  static GUEST: number = 1;
  static NOT_ACTIVATED: number = 2;

  static schema = {
    name: "User",
    primaryKey: "id",
    properties: {
      id: "int",
      etc...
    }
}

Accessing an object instance

const users = realm.objects("User");
console.log("Loaded", users[0]);

lib/browser/objects.js (the error is thrown here)

Console output

Error

Anybody knows the reason (or a fix)?

I created an issue from this comment #3673