Source code
Revision control
Copy as Markdown
Other Tools
const EMPTY = 0;
const INLINE_STORAGE = 10;
const NON_INLINE_STORAGE = 1024;
class DetachedInt32Array extends Int32Array {
constructor(...args) {
super(...args);
detachArrayBuffer(this.buffer);
}
}
function throwsTypeError(fn) {
try {
fn();
} catch (e) {
assertEq(e instanceof TypeError, true);
return true;
}
return false;
}
// Non-standard: Accessing elements of detached array buffers should throw, but
// this is currently not implemented.
const ACCESS_ON_DETACHED_ARRAY_BUFFER_THROWS = (() => {
let ta = new DetachedInt32Array(10);
let throws = throwsTypeError(() => ta[0]);
// Ensure [[Get]] and [[GetOwnProperty]] return consistent results.
assertEq(throwsTypeError(() => Object.getOwnPropertyDescriptor(ta, 0)), throws);
return throws;
})();
function maybeThrowOnDetached(fn, returnValue) {
if (ACCESS_ON_DETACHED_ARRAY_BUFFER_THROWS) {
assertThrowsInstanceOf(fn, TypeError);
return returnValue;
}
return fn();
}
// Empty typed arrays can be sealed.
{
let ta = new DetachedInt32Array(EMPTY);
Object.seal(ta);
assertEq(Object.isExtensible(ta), false);
assertEq(Object.isSealed(ta), true);
assertEq(Object.isFrozen(ta), true);
}
// Non-empty typed arrays can be sealed, but calling TestIntegrityLevel will
// throw on detached typed arrays.
for (let length of [INLINE_STORAGE, NON_INLINE_STORAGE]) {
let ta = new DetachedInt32Array(length);
Object.seal(ta);
assertEq(Object.isExtensible(ta), false);
assertEq(maybeThrowOnDetached(() => Object.isSealed(ta), true), true);
assertEq(maybeThrowOnDetached(() => Object.isFrozen(ta), true), true);
}
// Empty typed arrays can be frozen.
{
let ta = new DetachedInt32Array(EMPTY);
Object.freeze(ta);
assertEq(Object.isExtensible(ta), false);
assertEq(Object.isSealed(ta), true);
assertEq(Object.isFrozen(ta), true);
}
// Non-empty typed arrays cannot be frozen.
for (let length of [INLINE_STORAGE, NON_INLINE_STORAGE]) {
let ta = new DetachedInt32Array(length);
maybeThrowOnDetached(() => Object.freeze(ta));
assertEq(Object.isExtensible(ta), false);
assertEq(maybeThrowOnDetached(() => Object.isSealed(ta), true), true);
assertEq(maybeThrowOnDetached(() => Object.isFrozen(ta), true), true);
}
// Non-extensible empty typed arrays are sealed and frozen.
{
let ta = new DetachedInt32Array(EMPTY);
Object.preventExtensions(ta);
assertEq(Object.isExtensible(ta), false);
assertEq(Object.isSealed(ta), true);
assertEq(Object.isFrozen(ta), true);
}
// Calling TestIntegrityLevel will throw on detached typed arrays with non-zero
// length.
for (let length of [INLINE_STORAGE, NON_INLINE_STORAGE]) {
let ta = new DetachedInt32Array(length);
Object.preventExtensions(ta);
assertEq(Object.isExtensible(ta), false);
assertEq(maybeThrowOnDetached(() => Object.isSealed(ta), true), true);
assertEq(maybeThrowOnDetached(() => Object.isFrozen(ta), true), true);
}
if (typeof reportCompare === "function")
reportCompare(true, true);