Bug 603201 - Implement JS_ForwardSetPropertyTo. r=efaust

js/src/jsapi-tests/moz.build

@@ -30,6 +30,7 @@ UNIFIED_SOURCES += [
     'testExternalStrings.cpp',
     'testFindSCCs.cpp',
     'testForOfIterator.cpp',
+    'testForwardSetProperty.cpp',
     'testFreshGlobalEvalRedefinition.cpp',
     'testFunctionProperties.cpp',
     'testGCAllocator.cpp',

js/src/jsapi-tests/testForwardSetProperty.cpp

@@ -0,0 +1,106 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ */
+/* 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/. */
+
+#include "jsapi-tests/tests.h"
+
+BEGIN_TEST(testForwardSetProperty)
+{
+    JS::RootedValue v1(cx);
+    EVAL("var foundValue; \n"
+         "var obj1 = { set prop(val) { foundValue = this; } }; \n"
+         "obj1;",
+         &v1);
+
+    JS::RootedValue v2(cx);
+    EVAL("var obj2 = Object.create(obj1); \n"
+         "obj2;",
+         &v2);
+
+    JS::RootedValue v3(cx);
+    EVAL("var obj3 = {}; \n"
+         "obj3;",
+         &v3);
+
+    JS::RootedObject obj1(cx, &v1.toObject());
+    JS::RootedObject obj2(cx, &v2.toObject());
+    JS::RootedObject obj3(cx, &v3.toObject());
+
+    JS::RootedValue setval(cx, JS::Int32Value(42));
+
+    JS::RootedValue propkey(cx);
+    EVAL("'prop';", &propkey);
+
+    JS::RootedId prop(cx);
+    CHECK(JS_ValueToId(cx, propkey, &prop));
+
+    EXEC("function assertEq(a, b, msg) \n"
+         "{ \n"
+         "  if (!Object.is(a, b)) \n"
+         "    throw new Error('Assertion failure: ' + msg); \n"
+         "}");
+
+    // Non-strict setter
+
+    CHECK(JS_ForwardSetPropertyTo(cx, obj2, prop, v3, true, setval));
+
+    EXEC("assertEq(foundValue, obj3, 'wrong receiver passed to setter');");
+
+    CHECK(JS_ForwardSetPropertyTo(cx, obj2, prop, setval, true, setval));
+
+    EXEC("assertEq(typeof foundValue === 'object', true, \n"
+         "         'passing 42 as receiver to non-strict setter ' + \n"
+         "         'must box');");
+
+    EXEC("assertEq(foundValue instanceof Number, true, \n"
+         "         'passing 42 as receiver to non-strict setter ' + \n"
+         "         'must box to a Number');");
+
+    EXEC("assertEq(foundValue.valueOf(), 42, \n"
+         "         'passing 42 as receiver to non-strict setter ' + \n"
+         "         'must box to new Number(42)');");
+
+    // Strict setter
+
+    EVAL("obj1 = { set prop(val) { 'use strict'; foundValue = this; } }; \n"
+         "obj1;",
+         &v1);
+
+    CHECK(JS_ForwardSetPropertyTo(cx, obj2, prop, v3, true, setval));
+
+    EXEC("assertEq(foundValue, obj3, 'wrong receiver passed to strict setter');");
+
+    CHECK(JS_ForwardSetPropertyTo(cx, obj2, prop, setval, true, setval));
+
+
+    JS::RootedValue strictSetSupported(cx);
+    EVAL("var strictSetSupported = false; \n"
+         "Object.defineProperty(Object.prototype, \n"
+         "                      'strictSetter', \n"
+         "                      { \n"
+         "                        set(v) { \n"
+         "                          'use strict'; \n"
+         "                          strictSetSupported = \n"
+         "                            typeof this === 'number'; \n"
+         "                        } \n"
+         "                      }); \n"
+         "17..strictSetter = 42; \n"
+         "strictSetSupported;",
+         &strictSetSupported);
+    CHECK(strictSetSupported.isBoolean());
+
+    if (strictSetSupported.toBoolean()) {
+        // XXX Bug 603201 will fix this.
+        MOZ_ASSERT(false,
+                   "remove the support-testing check when bug 603201 is fixt");
+        EXEC("assertEq(foundValue, 42, \n"
+             "         '42 passed as receiver to strict setter ' + \n"
+             "         'was mangled');");
+    }
+
+    return true;
+}
+END_TEST(testForwardSetProperty)

js/src/jsapi.cpp

@@ -3054,6 +3054,24 @@ JS_SetPropertyById(JSContext *cx, HandleObject obj, HandleId id, HandleValue v)
     return JSObject::setGeneric(cx, obj, obj, id, &value, false);
 }
 
+JS_PUBLIC_API(bool)
+JS_ForwardSetPropertyTo(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleValue onBehalfOf,
+                        bool strict, JS::HandleValue v)
+{
+    AssertHeapIsIdle(cx);
+    CHECK_REQUEST(cx);
+    assertSameCompartment(cx, obj, id);
+    assertSameCompartment(cx, onBehalfOf);
+
+    // XXX Bug 603201 will eliminate this ToObject.
+    RootedObject receiver(cx, ToObject(cx, onBehalfOf));
+    if (!receiver)
+        return false;
+
+    RootedValue value(cx, v);
+    return JSObject::setGeneric(cx, obj, receiver, id, &value, strict);
+}
+
 static bool
 SetElement(JSContext *cx, HandleObject obj, uint32_t index, MutableHandleValue vp)
 {

js/src/jsapi.h

@@ -3213,6 +3213,10 @@ JS_SetProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::Handle
 extern JS_PUBLIC_API(bool)
 JS_SetPropertyById(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleValue v);
 
+extern JS_PUBLIC_API(bool)
+JS_ForwardSetPropertyTo(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleValue onBehalfOf,
+                        bool strict, JS::HandleValue vp);
+
 extern JS_PUBLIC_API(bool)
 JS_DeleteProperty(JSContext *cx, JS::HandleObject obj, const char *name);