Wikimedia Bugzilla is closed!

/**
 * @abstract
 * @method
 */
ve.foo.Bar.prototype.abstractMethod = function () {
   throw new Error( 've.foo.Bar subclass must implement abstractMethod');
};


x.abstractMethod();
> Error: ve.foo.Bar subclass must implement abstractMethod


/**
 * @abstract
 * @method
 */
ve.foo.Bar.prototype.abstractMethod = null;

x.abstractMethod();
> TypeError: Property 'abstractMethod' of object #<VeFooQuuxBar> is not a function

Seems easier to maintain and good enough.