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function testCongruent(i) {
var p = {};
var o = {
// Add toString as an own property, so it'll be always found on this object,
// even when properties are changed on the prototype.
toString: Object.prototype.toString,
// Add a custom prototype, so we can add @@toStringTag without modifying the
// shape of this object.
__proto__: p,
};
var xs = [{}, p];
var ys = ["[object Object]", "[object Test]"];
for (var j = 0; j <= 100; ++j) {
// Don't use if-statements to avoid cold code bailouts
var x = xs[(i === 1 && j === 100)|0];
var y = ys[(i === 1 && j === 100)|0];
// |o.toString()| must be executed twice, because |x[Symbol.toStringTag]| may
// have modified |o|.
var r = o.toString();
x[Symbol.toStringTag] = "Test";
var e = o.toString();
assertEq(r, "[object Object]");
assertEq(e, y);
}
}
for (var i = 0; i < 2; ++i) testCongruent(i);
function testUnobserved(i) {
var p = {};
var o = {
// Add toString as an own property, so it'll be always found on this object,
// even when properties are changed on the prototype.
toString: Object.prototype.toString,
// Add a custom prototype, so we can add @@toStringTag without modifying the
// shape of this object.
__proto__: p,
};
var xs = [{}, p];
var ys = [false, true];
for (var j = 0; j <= 100; ++j) {
// Don't use if-statements to avoid cold code bailouts
var x = xs[(i === 1 && j === 100)|0];
var y = ys[(i === 1 && j === 100)|0];
var executed = false;
Object.defineProperty(x, Symbol.toStringTag, {
configurable: true,
get() {
executed = true;
}
});
// |o.toString()| must be executed even when the result isn't observed.
o.toString();
assertEq(executed, y);
}
}
for (var i = 0; i < 2; ++i) testUnobserved(i);
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