[BUG] [REGRESSION] Extra class properties with incorrect types added

[hakimio]

Is there an existing issue for this?

• [X] I have searched the existing issues

Nature of Your Project

TypeScript

Current Behavior

Let's say we have User entity defined the following way:

export class User extends _._cuidAspect(_._managedAspect(_UserAspect(__.Entity))) {}

The class already inherits cuidAspect and managedAspect. cuidAspect defined as:

export function _cuidAspect<TBase extends new (...args: any[]) => object>(Base: TBase) {
  return class cuid extends Base {
        ID?: string | null;
      static readonly actions: Record<never, never>
  };
}

Now, for whatever reason cds-typer decided to duplicate the inherited fields on the base class with different typing (ID?: string vs ID?: string | null;):

export function _UserAspect<TBase extends new (...args: any[]) => object>(Base: TBase) {
  return class User extends Base {
        ID?: string;
        createdAt?: __.CdsTimestamp | null;
    /**
    * Canonical user ID
    */
        createdBy?: _.User | null;
        modifiedAt?: __.CdsTimestamp | null;
    /**
    * Canonical user ID
    */
        modifiedBy?: _.User | null;
          };
}

The duplicated fields appeared in the service class definitions but not in the db schema classes and because of this inconsistency I know get TS errors:

X [ERROR] NG2: Type 'import("models/gc/crm/index").User' is not assignable to type 'import("models/CrmService/index").User'.
  Types of property 'ID' are incompatible.
    Type 'string | null | undefined' is not assignable to type 'string | undefined'.
      Type 'null' is not assignable to type 'string | undefined'.

Expected Behavior

No TS errors after cds-typer update.

Steps To Reproduce

No response

Environment

- **OS**: Windows 10
- **Node**: 20.11.0
- **npm**:
- **cds-typer**: 0.20.1
- **cds**: 7.8.2

Repository Containing a Minimal Reproducible Example

No response

Anything else?

The last tested cds-typer version without the TS errors: 0.16.0