Bug 1192297 - Rephrase Proxy static methods to make it clearer that the handler->hasPrototype() case is the weird case. r=Waldo.

--HG--
extra : commitid : ESIC2Z4wS6J
extra : rebase_source : 9cde8160d79fe11317ed59b8df86454dcae605cc

js/src/proxy/Proxy.cpp

@@ -88,17 +88,6 @@ js::assertEnteredPolicy(JSContext* cx, JSObject* proxy, jsid id,
 }
 #endif
 
-#define INVOKE_ON_PROTOTYPE(cx, handler, proxy, protoCall)                   \
-    JS_BEGIN_MACRO                                                           \
-        RootedObject proto(cx);                                              \
-        if (!GetPrototype(cx, proxy, &proto))                                \
-            return false;                                                    \
-        if (!proto)                                                          \
-            return true;                                                     \
-        assertSameCompartment(cx, proxy, proto);                             \
-        return protoCall;                                                    \
-    JS_END_MACRO                                                             \
-
 bool
 Proxy::getPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                              MutableHandle<PropertyDescriptor> desc)
@@ -109,13 +98,12 @@ Proxy::getPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
     AutoEnterPolicy policy(cx, handler, proxy, id, BaseProxyHandler::GET_PROPERTY_DESCRIPTOR, true);
     if (!policy.allowed())
         return policy.returnValue();
-    if (!handler->hasPrototype())
+
+    // Special case. See the comment on BaseProxyHandler::mHasPrototype.
+    if (handler->hasPrototype())
+        return handler->BaseProxyHandler::getPropertyDescriptor(cx, proxy, id, desc);
+
     return handler->getPropertyDescriptor(cx, proxy, id, desc);
-    if (!handler->getOwnPropertyDescriptor(cx, proxy, id, desc))
-        return false;
-    if (desc.object())
-        return true;
-    INVOKE_ON_PROTOTYPE(cx, handler, proxy, GetPropertyDescriptor(cx, proto, id, desc));
 }
 
 bool
@@ -241,16 +229,23 @@ Proxy::has(JSContext* cx, HandleObject proxy, HandleId id, bool* bp)
     AutoEnterPolicy policy(cx, handler, proxy, id, BaseProxyHandler::GET, true);
     if (!policy.allowed())
         return policy.returnValue();
-    if (!handler->hasPrototype())
-        return handler->has(cx, proxy, id, bp);
+
+    if (handler->hasPrototype()) {
         if (!handler->hasOwn(cx, proxy, id, bp))
             return false;
         if (*bp)
             return true;
-    bool Bp;
-    INVOKE_ON_PROTOTYPE(cx, handler, proxy,
-                        JS_HasPropertyById(cx, proto, id, &Bp) &&
-                        ((*bp = Bp) || true));
+
+        RootedObject proto(cx);
+        if (!GetPrototype(cx, proxy, &proto))
+            return false;
+        if (!proto)
+            return true;
+
+        return HasProperty(cx, proto, id, bp);
+    }
+
+    return handler->has(cx, proxy, id, bp);
 }
 
 bool
@@ -275,16 +270,22 @@ Proxy::get(JSContext* cx, HandleObject proxy, HandleObject receiver, HandleId id
     AutoEnterPolicy policy(cx, handler, proxy, id, BaseProxyHandler::GET, true);
     if (!policy.allowed())
         return policy.returnValue();
+
+    if (handler->hasPrototype()) {
         bool own;
-    if (!handler->hasPrototype()) {
-        own = true;
-    } else {
         if (!handler->hasOwn(cx, proxy, id, &own))
             return false;
+        if (!own) {
+            RootedObject proto(cx);
+            if (!GetPrototype(cx, proxy, &proto))
+                return false;
+            if (!proto)
+                return true;
+            return GetProperty(cx, proto, receiver, id, vp);
         }
-    if (own)
+    }
+
     return handler->get(cx, proxy, receiver, id, vp);
-    INVOKE_ON_PROTOTYPE(cx, handler, proxy, GetProperty(cx, proto, receiver, id, vp));
 }
 
 bool
@@ -343,18 +344,8 @@ Proxy::enumerate(JSContext* cx, HandleObject proxy, MutableHandleObject objp)
     JS_CHECK_RECURSION(cx, return false);
     const BaseProxyHandler* handler = proxy->as<ProxyObject>().handler();
     objp.set(nullptr); // default result if we refuse to perform this action
-    if (!handler->hasPrototype()) {
-        AutoEnterPolicy policy(cx, handler, proxy, JSID_VOIDHANDLE,
-                               BaseProxyHandler::ENUMERATE, true);
-        // If the policy denies access but wants us to return true, we need
-        // to hand a valid (empty) iterator object to the caller.
-        if (!policy.allowed()) {
-            return policy.returnValue() &&
-                   NewEmptyPropertyIterator(cx, 0, objp);
-        }
-        return handler->enumerate(cx, proxy, objp);
-    }
 
+    if (handler->hasPrototype()) {
         AutoIdVector props(cx);
         if (!Proxy::getOwnEnumerablePropertyKeys(cx, proxy, props))
             return false;
@@ -370,6 +361,18 @@ Proxy::enumerate(JSContext* cx, HandleObject proxy, MutableHandleObject objp)
         return GetPropertyKeys(cx, proto, 0, &protoProps) &&
                AppendUnique(cx, props, protoProps) &&
                EnumeratedIdVectorToIterator(cx, proxy, 0, props, objp);
+    }
+
+    AutoEnterPolicy policy(cx, handler, proxy, JSID_VOIDHANDLE,
+                           BaseProxyHandler::ENUMERATE, true);
+
+    // If the policy denies access but wants us to return true, we need
+    // to hand a valid (empty) iterator object to the caller.
+    if (!policy.allowed()) {
+        return policy.returnValue() &&
+            NewEmptyPropertyIterator(cx, 0, objp);
+    }
+    return handler->enumerate(cx, proxy, objp);
 }
 
 bool