Method indexOf

packages/reactivity/__tests__/reactiveArray.spec.ts:324–327

(searchElement: T, fromIndex?: number | undefined)

      }

      indexOf(searchElement: T, fromIndex?: number | undefined): number {
        this.lastSearched = searchElement
        return super.indexOf(searchElement, fromIndex)
      }
    }

    test('calls correct mutation method on Array subclass', () => {