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// When the abstract operation AddToKeptObjects is called with a target object
// reference, it adds the target to an identity Set that will point strongly at
// the target until the end of the current Job.
//
// When WeakRef.prototype.deref is called, the referent (if it's not already
// dead) is kept alive so that subsequent, synchronous accesses also return the
// object.
function testSameCompartmentWeakRef(
targetReachable,
weakRefReachable) {
let target = {};
let weakref = new WeakRef(target);
assertEq(weakref.deref(), target);
if (!targetReachable) {
target = undefined;
}
if (!weakRefReachable) {
weakRef = undefined;
}
clearKeptObjects();
gc();
if (weakRefReachable) {
if (targetReachable) {
assertEq(weakref.deref(), target);
} else {
assertEq(weakref.deref(), undefined);
}
}
}
let serial = 0;
function testCrossCompartmentWeakRef(
targetReachable,
weakRefReachable,
collectTargetZone,
collectWeakRefZone,
sameZone) {
gc();
let id = serial++;
let global = newGlobal(sameZone ? {sameZoneAs: this} : {newCompartment: true});
global.eval('var target = {};');
global.target.id = id;
let weakref = new WeakRef(global.target);
assertEq(weakref.deref(), global.target);
if (!targetReachable) {
global.target = undefined;
}
if (!weakRefReachable) {
weakRef = undefined;
}
if (collectTargetZone || collectWeakRefZone) {
clearKeptObjects();
if (collectTargetZone) {
schedulezone(global);
}
if (collectWeakRefZone) {
schedulezone(this);
}
// Incremental GC so we use sweep groups. Shrinking GC to test updating
// pointers.
startgc(1, 'shrinking');
while (gcstate() !== 'NotActive') {
gcslice(1000, {dontStart: true});
}
}
if (!(collectWeakRefZone && !weakRefReachable)) {
if (collectTargetZone && !targetReachable) {
assertEq(weakref.deref(), undefined);
} else if (targetReachable) {
assertEq(weakref.deref(), global.target);
} else {
// Target is not strongly reachable but hasn't been collected yet. We
// can get it back through deref() but must check it based on properties.
assertEq(weakref.deref() !== undefined, true);
assertEq(weakref.deref().id, id);
}
}
}
gczeal(0);
for (let targetReachable of [true, false]) {
for (let weakRefReachable of [true, false]) {
testSameCompartmentWeakRef(targetReachable, weakRefReachable);
}
}
for (let targetReachable of [true, false]) {
for (let weakRefReachable of [true, false]) {
for (let collectTargetZone of [true, false]) {
for (let collectWeakRefZone of [true, false]) {
for (let sameZone of [true, false]) {
if (sameZone && (collectTargetZone != collectWeakRefZone)) {
continue;
}
testCrossCompartmentWeakRef(targetReachable, weakRefReachable,
collectTargetZone, collectWeakRefZone, sameZone);
}
}
}
}
}