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var canOptimize = getSelfHostedValue("CanOptimizeArraySpecies");
function test1() {
for (var i = 0; i < 20; i++) {
// If one of these starts failing, we should probably change how
// CanOptimizeArraySpecies is implemented to avoid perf problems!
assertEq(canOptimize([1, 2, 3]), true);
var a = [];
for (var j = 0; j < 10; j++) {
a.push(j);
}
assertEq(canOptimize(a), true);
assertEq(canOptimize(a.slice()), true);
assertEq(canOptimize(a.map(x => x + 1)), true);
// These aren't plain arrays.
assertEq(canOptimize({}), false);
Object.setPrototypeOf(a, Object.create(Array.prototype));
assertEq(canOptimize(a), false);
a = [];
a.constructor = function() {};
assertEq(canOptimize(a), false);
}
}
test1();
function test2() {
for (var i = 0; i < 20; i++) {
assertEq(canOptimize([1, 2, 3]), i <= 16);
if (i === 16) {
// Pop the fuse.
Array.prototype.constructor = Object;
}
}
}
test2();