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setJitCompilerOption("ic.force-megamorphic", 1);
// The megamorphic SetElem.
function doSet(obj, prop, v) {
"use strict";
obj[prop] = v;
}
function test() {
with ({}) {} // No inlining.
for (var i = 0; i < 10; i++) {
var obj = {};
// Test simple add/set cases.
for (var j = 0; j < 10; j++) {
doSet(obj, "x" + (j % 8), j);
}
// Ensure __proto__ is handled correctly.
var setterCalls = 0;
var proto = {set someSetter(v) { setterCalls++; }};
doSet(obj, "__proto__", proto);
assertEq(Object.getPrototypeOf(obj), proto);
// Can't shadow a non-writable data property.
Object.defineProperty(proto, "readonly",
{value: 1, writable: false, configurable: true});
var ex = null;
try {
doSet(obj, "readonly", 2);
} catch (e) {
ex = e;
}
assertEq(ex instanceof TypeError, true);
assertEq(obj.readonly, 1);
// Setter on the proto chain must be called.
doSet(obj, "someSetter", 1);
assertEq(setterCalls, 1);
// Can't add properties if non-extensible.
Object.preventExtensions(obj);
ex = null;
try {
doSet(obj, "foo", 1);
} catch (e) {
ex = e;
}
assertEq(ex instanceof TypeError, true);
assertEq(JSON.stringify(obj), '{"x0":8,"x1":9,"x2":2,"x3":3,"x4":4,"x5":5,"x6":6,"x7":7}');
}
}
test();