Mixins Overrides Drop Documentation

[LukeAbby]

Note: This is a refiling of https://github.com/microsoft/TypeScript/issues/60871 in accordance to the instructions to follow after being closed in https://github.com/microsoft/TypeScript/issues/62827.

Search Terms

mixins overrides, documentation dropped

Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about documentation, mixins, etc.

Playground

https://www.typescriptlang.org/play/?ts=5.7.2#code/CYUwxgNghgTiAEkoGdnwEIpAYWq+A3gFDynwD0AVJfMgPYC2CwdYArkwHYAuU3AlnU7xK5EmWS8BYeE24ALOsAAUASgBc8ThwBGIGAG4iAXyJFuATwAOCAIKcL2IZJhsw3OjHgBeeFB0uUO5aIADu8MoAdNGwAObImlAOANoAuqo+AHzwdDoAVuDcZgBmbJzugsIAsvwAHgA8ACrwILXcIJzAaPaOztyu7p6ZypjIOHgJ8I0ZxKT+gcFI+DW1-Jy4KGit7Z1oo+ObhOKkYH0DHjBRMTDxiSnpR2QSbDaX0ZFxyKpGT6akpuI4Nw2DBqnU1htUEYAeRyPAAPJeBieBDIfgMKwQCzwCx0NiIJLwUIwfjtdREWGICbwFYQ6kEUyU0BIODwUrlARCGl1JotNodLrwHpOTguNwXYb7SGTaaaSw2OjFbmrdbUgBkUyMRGZ0FZSzQKxAwD5O0FKxGWGlM3Ekj4-BkckUKg0Wl0+mhZkNwEijqURkpZAAevAAHJ0eAsdhcKSVSJAA

Code

declare class BaseClass {
    /** some documentation */
    static method(): number;
}

type AnyConstructor = abstract new (...args: any[]) => object

function Mix<T extends AnyConstructor>(BaseClass: T) {
  abstract class MixinClass extends BaseClass {
    constructor(...args: any[]) {
      super(...args);
    }
  }

  return MixinClass;
}

// Or more simply you can write:
class MixinClass {}
declare function Mix<T extends AnyConstructor>(BaseClass: T): typeof MixinClass & T;

declare class Mixed extends Mix(BaseClass) {
  static method(): number;
}

Mixed.method;
//    ^ No documentation.

Actual behavior

Overrides of a mixin class does not have documentation.

Notably if you don't override the method the documentation does show up. This shows it's possible to get it.

Expected behavior

It should inherit documentation.