Prettier 1.10.2
Playground link

--parser typescript

Input:

export class CoreModule {
  @Input() @Output() prop: string;

  constructor(@Optional() @SkipSelf() parentModule: CoreModule) {}
}

Output:

export class CoreModule {
  @Input()
  @Output()
  prop: string;

  constructor(
    @Optional()
    @SkipSelf()
    parentModule: CoreModule
  ) {}
}

Expected output:

No difference between input and output.

If we did the same thing with only one decorator, the result would be:

export class CoreModule {
  @Input() prop: string;

  constructor(@Optional() parentModule: CoreModule) {}
}

In this sense I don't think breaking on multiple decorators adds any value, instead adds more visual noise and makes it harder to spot arguments in e.g. the constructor.