test("Inline cache invalidated by deleting property from unique shape", () => { // Create an object with an unique shape by adding a huge amount of properties. let o = {}; for (let x = 0; x < 1000; ++x) { o["prop" + x] = x; } function ic(o) { return o.prop2; } let first = ic(o); delete o.prop2; let second = ic(o); expect(first).toBe(2); expect(second).toBeUndefined(); });