1 files changed, 156 insertions, 0 deletions
diff --git a/js/src/builtin/Reflect.js b/js/src/builtin/Reflect.js
new file mode 100644
index 0000000000..dc81f0d520
--- /dev/null
+++ b/js/src/builtin/Reflect.js
@@ -0,0 +1,156 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// ES2017 draft rev a785b0832b071f505a694e1946182adeab84c972
+// 7.3.17 CreateListFromArrayLike (obj [ , elementTypes ] )
+function CreateListFromArrayLikeForArgs(obj) {
+    // Step 1 (not applicable).
+
+    // Step 2.
+    assert(IsObject(obj), "object must be passed to CreateListFromArrayLikeForArgs");
+
+    // Step 3.
+    var len = ToLength(obj.length);
+
+    // This version of CreateListFromArrayLike is only used for argument lists.
+    if (len > MAX_ARGS_LENGTH)
+        ThrowRangeError(JSMSG_TOO_MANY_ARGUMENTS);
+
+    // Steps 4-6.
+    var list = std_Array(len);
+    for (var i = 0; i < len; i++)
+        _DefineDataProperty(list, i, obj[i]);
+
+    // Step 7.
+    return list;
+}
+
+// ES2017 draft rev a785b0832b071f505a694e1946182adeab84c972
+// 26.1.1 Reflect.apply ( target, thisArgument, argumentsList )
+function Reflect_apply(target, thisArgument, argumentsList) {
+    // Step 1.
+    if (!IsCallable(target))
+        ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, target));
+
+    // Step 2.
+    if (!IsObject(argumentsList)) {
+        ThrowTypeError(JSMSG_OBJECT_REQUIRED_ARG, "`argumentsList`", "Reflect.apply",
+                       ToSource(argumentsList));
+    }
+
+    // Steps 2-4.
+    return callFunction(std_Function_apply, target, thisArgument, argumentsList);
+}
+
+// ES2017 draft rev a785b0832b071f505a694e1946182adeab84c972
+// 26.1.2 Reflect.construct ( target, argumentsList [ , newTarget ] )
+function Reflect_construct(target, argumentsList/*, newTarget*/) {
+    // Step 1.
+    if (!IsConstructor(target))
+        ThrowTypeError(JSMSG_NOT_CONSTRUCTOR, DecompileArg(0, target));
+
+    // Steps 2-3.
+    var newTarget;
+    if (arguments.length > 2) {
+        newTarget = arguments[2];
+        if (!IsConstructor(newTarget))
+            ThrowTypeError(JSMSG_NOT_CONSTRUCTOR, DecompileArg(2, newTarget));
+    } else {
+        newTarget = target;
+    }
+
+    // Step 4.
+    if (!IsObject(argumentsList)) {
+        ThrowTypeError(JSMSG_OBJECT_REQUIRED_ARG, "`argumentsList`", "Reflect.construct",
+                       ToSource(argumentsList));
+    }
+
+    // Fast path when we can avoid calling CreateListFromArrayLikeForArgs().
+    var args = (IsPackedArray(argumentsList) && argumentsList.length <= MAX_ARGS_LENGTH)
+               ? argumentsList
+               : CreateListFromArrayLikeForArgs(argumentsList);
+
+    // Step 5.
+    switch (args.length) {
+      case 0:
+        return constructContentFunction(target, newTarget);
+      case 1:
+        return constructContentFunction(target, newTarget, SPREAD(args, 1));
+      case 2:
+        return constructContentFunction(target, newTarget, SPREAD(args, 2));
+      case 3:
+        return constructContentFunction(target, newTarget, SPREAD(args, 3));
+      case 4:
+        return constructContentFunction(target, newTarget, SPREAD(args, 4));
+      case 5:
+        return constructContentFunction(target, newTarget, SPREAD(args, 5));
+      case 6:
+        return constructContentFunction(target, newTarget, SPREAD(args, 6));
+      case 7:
+        return constructContentFunction(target, newTarget, SPREAD(args, 7));
+      case 8:
+        return constructContentFunction(target, newTarget, SPREAD(args, 8));
+      case 9:
+        return constructContentFunction(target, newTarget, SPREAD(args, 9));
+      case 10:
+        return constructContentFunction(target, newTarget, SPREAD(args, 10));
+      case 11:
+        return constructContentFunction(target, newTarget, SPREAD(args, 11));
+      case 12:
+        return constructContentFunction(target, newTarget, SPREAD(args, 12));
+      default:
+        return _ConstructFunction(target, newTarget, args);
+    }
+}
+
+// ES2017 draft rev 6859bb9ccaea9c6ede81d71e5320e3833b92cb3e
+// 26.1.3 Reflect.defineProperty ( target, propertyKey, attributes )
+function Reflect_defineProperty(obj, propertyKey, attributes) {
+    // Steps 1-4.
+    return ObjectOrReflectDefineProperty(obj, propertyKey, attributes, false);
+}
+
+// ES2017 draft rev 6859bb9ccaea9c6ede81d71e5320e3833b92cb3e
+// 26.1.6 Reflect.getOwnPropertyDescriptor ( target, propertyKey )
+function Reflect_getOwnPropertyDescriptor(target, propertyKey) {
+    // Step 1.
+    if (!IsObject(target))
+        ThrowTypeError(JSMSG_OBJECT_REQUIRED, DecompileArg(0, target));
+
+    // Steps 2-3.
+    // The other steps are identical to Object.getOwnPropertyDescriptor().
+    return ObjectGetOwnPropertyDescriptor(target, propertyKey);
+}
+
+// ES2017 draft rev a785b0832b071f505a694e1946182adeab84c972
+// 26.1.8 Reflect.has ( target, propertyKey )
+function Reflect_has(target, propertyKey) {
+    // Step 1.
+    if (!IsObject(target)) {
+        ThrowTypeError(JSMSG_OBJECT_REQUIRED_ARG, "`target`", "Reflect.has",
+                       ToSource(target));
+    }
+
+    // Steps 2-3 are identical to the runtime semantics of the "in" operator.
+    return propertyKey in target;
+}
+
+// ES2018 draft rev 0525bb33861c7f4e9850f8a222c89642947c4b9c
+// 26.1.5 Reflect.get ( target, propertyKey [ , receiver ] )
+function Reflect_get(target, propertyKey/*, receiver*/) {
+    // Step 1.
+    if (!IsObject(target)) {
+        ThrowTypeError(JSMSG_OBJECT_REQUIRED_ARG, "`target`", "Reflect.get",
+                       ToSource(target));
+    }
+
+    // Step 3 (reordered).
+    if (arguments.length > 2) {
+        // Steps 2, 4.
+        return getPropertySuper(target, propertyKey, arguments[2]);
+    }
+
+    // Steps 2, 4.
+    return target[propertyKey];
+}