test_reflect_construct_newtarget_wrappers.cjs
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test_reflect_construct_newtarget_wrappers.cjs
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	function assert(condition, message) {
	if (!condition) throw new Error(message);
	}

	const BooleanNewTarget = function BooleanNewTarget() {};
	const booleanObject = Reflect.construct(Boolean, [], BooleanNewTarget);

	assert(
	Boolean.prototype.valueOf.call(booleanObject) === false,
	'Reflect.construct(Boolean, [], newTarget) should initialize [[BooleanData]]',
	);
	assert(
	Object.getPrototypeOf(booleanObject) === BooleanNewTarget.prototype,
	'Reflect.construct(Boolean, [], newTarget) should use newTarget.prototype',
	);

	const NumberNewTarget = function NumberNewTarget() {};
	const numberObject = Reflect.construct(Number, [42], NumberNewTarget);

	assert(
	Number.prototype.valueOf.call(numberObject) === 42,
	'Reflect.construct(Number, [], newTarget) should initialize [[NumberData]]',
	);
	assert(
	Object.getPrototypeOf(numberObject) === NumberNewTarget.prototype,
	'Reflect.construct(Number, [], newTarget) should use newTarget.prototype',
	);

	const StringNewTarget = function StringNewTarget() {};
	const stringObject = Reflect.construct(String, ['ant'], StringNewTarget);

	assert(
	String.prototype.valueOf.call(stringObject) === 'ant',
	'Reflect.construct(String, [], newTarget) should initialize [[StringData]]',
	);
	assert(
	Object.getPrototypeOf(stringObject) === StringNewTarget.prototype,
	'Reflect.construct(String, [], newTarget) should use newTarget.prototype',
	);

	function supportsReflectConstructNewTarget() {
	try {
	return !Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function() {}));
	} catch (_) {
	return false;
	}
	}

	function inherit(Sub, Super) {
	Sub.prototype = Object.create(Super && Super.prototype, {
	constructor: { value: Sub, writable: true, configurable: true },
	});
	Object.defineProperty(Sub, 'prototype', { writable: false });
	if (Super) Object.setPrototypeOf(Sub, Super);
	}

	function getPrototypeOf(value) {
	return Object.getPrototypeOf.bind()(value);
	}

	function constructSuper(self, Constructor, args) {
	const Super = getPrototypeOf(Constructor);
	return Reflect.construct(Super, args \|\| [], getPrototypeOf(self).constructor);
	}

	const SafeWeakMap = (function(Super) {
	function SafeWeakMap(iterable) {
	return constructSuper(this, SafeWeakMap, [iterable]);
	}
	inherit(SafeWeakMap, Super);
	Object.setPrototypeOf(SafeWeakMap.prototype, null);
	Object.freeze(SafeWeakMap.prototype);
	Object.freeze(SafeWeakMap);
	return SafeWeakMap;
	})(WeakMap);

	assert(supportsReflectConstructNewTarget(), 'Reflect.construct newTarget probe should pass');

	const safeWeakMap = new SafeWeakMap();
	assert(safeWeakMap instanceof SafeWeakMap, 'derived WeakMap should use derived prototype');

	console.log('reflect:construct-newtarget-wrappers:ok');

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