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// Test constructing a function when the |.prototype| property isn't an object.
function test(proto) {
function Klass() {
this.prop = 1;
}
Klass.prototype = proto;
const N = 100;
let c = 0;
for (let i = 0; i < N; ++i) {
// Create a new object.
let o = new Klass();
// Read a property from the new object to ensure it was correctly allocated
// and initialised.
c += o.prop;
// The prototype defaults to %Object.prototype% when the |.prototype|
// property isn't an object.
assertEq(Object.getPrototypeOf(o), Object.prototype);
}
assertEq(c, N);
}
const primitivesTypes = [
undefined,
null,
123,
true,
"str",
Symbol(),
123n,
];
for (let primitive of primitivesTypes) {
// Create a fresh function object to avoid type pollution.
let fn = Function(`return ${test}`)();
fn(primitive);
}
// Repeat the test from above, but this time |Klass| is a cross-realm function.
function testCrossRealm(proto) {
const otherGlobal = newGlobal();
const Klass = otherGlobal.eval(`
function Klass() {
this.prop = 1;
}
Klass;
`);
Klass.prototype = proto;
const N = 100;
let c = 0;
for (let i = 0; i < N; ++i) {
// Create a new object.
let o = new Klass();
// Read a property from the new object to ensure it was correctly allocated
// and initialised.
c += o.prop;
// The prototype defaults to %Object.prototype% when the |.prototype|
// property isn't an object.
assertEq(Object.getPrototypeOf(o), otherGlobal.Object.prototype);
}
assertEq(c, N);
}
for (let primitive of primitivesTypes) {
// Create a fresh function object to avoid type pollution.
let fn = Function(`return ${testCrossRealm}`)();
fn(primitive);
}
// Repeat the test from above, but this time |Klass| is a cross-realm new.target.
function testCrossRealmNewTarget(proto) {
const otherGlobal = newGlobal();
const Klass = otherGlobal.eval(`
function Klass() {}
Klass;
`);
Klass.prototype = proto;
class C {
constructor() {
this.prop = 1;
}
}
class D extends C {
constructor() {
super();
}
}
const N = 100;
let c = 0;
for (let i = 0; i < N; ++i) {
// Create a new object.
let o = Reflect.construct(D, [], Klass);
// Read a property from the new object to ensure it was correctly allocated
// and initialised.
c += o.prop;
// The prototype defaults to %Object.prototype% when the |.prototype|
// property isn't an object.
assertEq(Object.getPrototypeOf(o), otherGlobal.Object.prototype);
}
assertEq(c, N);
}
for (let primitive of primitivesTypes) {
// Create a fresh function object to avoid type pollution.
let fn = Function(`return ${testCrossRealmNewTarget}`)();
fn(primitive);
}