/src/a.js(10,7): error TS2417: Class static side 'typeof ElementsArray' incorrectly extends base class static side '{ isArray(arg: any): arg is any[]; readonly prototype: any[]; }'.
  Types of property 'isArray' are incompatible.
    Type '(arg: any) => boolean' is not assignable to type '(arg: any) => arg is any[]'.
      Signature '(arg: any): boolean' must be a type predicate.


==== /src/a.js (1 errors) ====
    class Thing {
        static {
            this.doSomething = () => {};
        }
    }
    
    Thing.doSomething();
    
    // GH#46468
    class ElementsArray extends Array {
          ~~~~~~~~~~~~~
!!! error TS2417: Class static side 'typeof ElementsArray' incorrectly extends base class static side '{ isArray(arg: any): arg is any[]; readonly prototype: any[]; }'.
!!! error TS2417:   Types of property 'isArray' are incompatible.
!!! error TS2417:     Type '(arg: any) => boolean' is not assignable to type '(arg: any) => arg is any[]'.
!!! error TS2417:       Signature '(arg: any): boolean' must be a type predicate.
        static {
            const superisArray = super.isArray;
            const customIsArray = (arg)=> superisArray(arg);
            this.isArray = customIsArray;
        }
    }
    
    ElementsArray.isArray(new ElementsArray());