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+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/ */
+
+// Reflect.construct invokes constructors.
+
+assertDeepEq(Reflect.construct(Object, []), {});
+assertDeepEq(Reflect.construct(String, ["hello"]), new String("hello"));
+
+// Constructing Date creates a real Date object.
+var d = Reflect.construct(Date, [1776, 6, 4]);
+assertEq(d instanceof Date, true);
+assertEq(d.getFullYear(), 1776); // non-generic method requires real Date object
+
+// [[Construct]] methods don't necessarily create new objects.
+var obj = {};
+assertEq(Reflect.construct(Object, [obj]), obj);
+
+
+// === Various kinds of constructors
+// We've already seen some builtin constructors.
+//
+// JS functions:
+function f(x) { this.x = x; }
+assertDeepEq(Reflect.construct(f, [3]), new f(3));
+f.prototype = Array.prototype;
+assertDeepEq(Reflect.construct(f, [3]), new f(3));
+
+// Bound functions:
+var bound = f.bind(null, "carrot");
+assertDeepEq(Reflect.construct(bound, []), new bound);
+
+// Classes:
+class Base {
+ constructor(...args) {
+ this.args = args;
+ this.newTarget = new.target;
+ }
+}
+class Derived extends Base {
+ constructor(...args) { super(...args); }
+}
+
+assertDeepEq(Reflect.construct(Base, []), new Base);
+assertDeepEq(Reflect.construct(Derived, [7]), new Derived(7));
+g = Derived.bind(null, "q");
+assertDeepEq(Reflect.construct(g, [8, 9]), new g(8, 9));
+
+// Cross-compartment wrappers:
+var g = newGlobal();
+var local = {here: this};
+g.eval("function F(arg) { this.arg = arg }");
+assertDeepEq(Reflect.construct(g.F, [local]), new g.F(local));
+
+// If first argument to Reflect.construct isn't a constructor, it throws a
+// TypeError.
+var nonConstructors = [
+ {},
+ Reflect.construct, // builtin functions aren't constructors
+ x => x + 1,
+ Math.max.bind(null, 0), // bound non-constructors aren't constructors
+ ((x, y) => x > y).bind(null, 0),
+
+ // A Proxy to a non-constructor function isn't a constructor, even if a
+ // construct handler is present.
+ new Proxy(Reflect.construct, {construct(){}}),
+];
+for (var obj of nonConstructors) {
+ assertThrowsInstanceOf(() => Reflect.construct(obj, []), TypeError);
+ assertThrowsInstanceOf(() => Reflect.construct(obj, [], Object), TypeError);
+}
+
+
+// === new.target tests
+
+// If the newTarget argument to Reflect.construct is missing, the target is used.
+function checkNewTarget() {
+ assertEq(new.target, expected);
+ expected = undefined;
+}
+var expected = checkNewTarget;
+Reflect.construct(checkNewTarget, []);
+
+// The newTarget argument is correctly passed to the constructor.
+var constructors = [Object, Function, f, bound];
+for (var ctor of constructors) {
+ expected = ctor;
+ Reflect.construct(checkNewTarget, [], ctor);
+ assertEq(expected, undefined);
+}
+
+// The newTarget argument must be a constructor.
+for (var v of SOME_PRIMITIVE_VALUES.concat(nonConstructors)) {
+ assertThrowsInstanceOf(() => Reflect.construct(checkNewTarget, [], v), TypeError);
+}
+
+// The builtin Array constructor uses new.target.prototype and always
+// creates a real array object.
+function someConstructor() {}
+var result = Reflect.construct(Array, [], someConstructor);
+assertEq(Reflect.getPrototypeOf(result), someConstructor.prototype);
+assertEq(result.length, 0);
+assertEq(Array.isArray(result), true);
+
+
+// For more Reflect.construct tests, see target.js and argumentsList.js.
+
+reportCompare(0, 0);