// Array.prototype.pop does a strict assignment to this.length even if the // caller is nonstrict. Bug 886087. load(libdir + "asserts.js"); // obj.length is read-only var obj = {pop: [].pop, 0: "zero"}; Object.defineProperty(obj, "length", {configurable: true, value: 1, writable: false}); assertThrowsInstanceOf(() => obj.pop(), TypeError); // obj.length has only a getter obj = {pop: [].pop, 0: "zero", get length() { return 1; }}; assertThrowsInstanceOf(() => obj.pop(), TypeError);