Bug 547140, part 1 - Remove JSRESOLVE_ASSIGNING. r=Waldo.

js/public/Class.h

@@ -127,9 +127,7 @@ typedef bool
 typedef bool
 (* JSResolveOp)(JSContext *cx, JS::HandleObject obj, JS::HandleId id);
 
-// Like JSResolveOp, but flags provide contextual information as follows:
-//
-//  JSRESOLVE_ASSIGNING   obj[id] is on the left-hand side of an assignment
+// Like JSResolveOp, except with a useless flags argument, always 0. Also:
 //
 // The *objp out parameter, on success, should be null to indicate that id
 // was not resolved; and non-null, referring to obj or one of its prototypes,

js/src/jsapi.cpp

@@ -3441,7 +3441,6 @@ JS_SetPropertyById(JSContext *cx, HandleObject obj, HandleId id, HandleValue v)
     AssertHeapIsIdle(cx);
     CHECK_REQUEST(cx);
     assertSameCompartment(cx, obj, id);
-    JSAutoResolveFlags rf(cx, JSRESOLVE_ASSIGNING);
 
     return JSObject::setGeneric(cx, obj, obj, id, &value, false);
 }
@@ -3452,7 +3451,6 @@ SetElement(JSContext *cx, HandleObject obj, uint32_t index, MutableHandleValue v
     AssertHeapIsIdle(cx);
     CHECK_REQUEST(cx);
     assertSameCompartment(cx, obj, vp);
-    JSAutoResolveFlags rf(cx, JSRESOLVE_ASSIGNING);
 
     return JSObject::setElement(cx, obj, obj, index, vp, false);
 }

js/src/jsapi.h

@@ -2331,11 +2331,6 @@ JS_StringToId(JSContext *cx, JS::HandleString s, JS::MutableHandleId idp);
 extern JS_PUBLIC_API(bool)
 JS_IdToValue(JSContext *cx, jsid id, JS::MutableHandle<JS::Value> vp);
 
-/*
- * JSNewResolveOp flag bits.
- */
-#define JSRESOLVE_ASSIGNING     0x01    /* resolve on the left of assignment */
-
 /*
  * Invoke the [[DefaultValue]] hook (see ES5 8.6.2) with the provided hint on
  * the specified object, computing a primitive default value for the object.

js/src/jsobj.cpp

@@ -1663,20 +1663,7 @@ Detecting(JSContext *cx, JSScript *script, jsbytecode *pc)
 unsigned
 js_InferFlags(JSContext *cx, unsigned defaultFlags)
 {
-    /*
-     * We intentionally want to look across compartment boundaries to correctly
-     * handle the case of cross-compartment property access.
-     */
-    jsbytecode *pc;
-    JSScript *script = cx->currentScript(&pc, JSContext::ALLOW_CROSS_COMPARTMENT);
-    if (!script)
-        return defaultFlags;
-
-    uint32_t format = js_CodeSpec[*pc].format;
-    unsigned flags = 0;
-    if (format & JOF_SET)
-        flags |= JSRESOLVE_ASSIGNING;
-    return flags;
+    return 0;
 }
 
 /* static */ bool
@@ -4904,7 +4891,7 @@ baseops::SetPropertyHelper(typename ExecutionModeTraits<mode>::ContextType cxArg
 
                 JSContext *cx = cxArg->asJSContext();
                 Rooted<PropertyDescriptor> pd(cx);
-                if (!Proxy::getPropertyDescriptor(cx, pobj, id, &pd, JSRESOLVE_ASSIGNING))
+                if (!Proxy::getPropertyDescriptor(cx, pobj, id, &pd, 0))
                     return false;
 
                 if ((pd.attributes() & (JSPROP_SHARED | JSPROP_SHADOWABLE)) == JSPROP_SHARED) {

js/src/jsproxy.cpp

@@ -159,7 +159,7 @@ BaseProxyHandler::set(JSContext *cx, HandleObject proxy, HandleObject receiver,
     assertEnteredPolicy(cx, proxy, id, SET);
 
     Rooted<PropertyDescriptor> desc(cx);
-    if (!getOwnPropertyDescriptor(cx, proxy, id, &desc, JSRESOLVE_ASSIGNING))
+    if (!getOwnPropertyDescriptor(cx, proxy, id, &desc, 0))
         return false;
     /* The control-flow here differs from ::get() because of the fall-through case below. */
     if (desc.object()) {
@@ -187,7 +187,7 @@ BaseProxyHandler::set(JSContext *cx, HandleObject proxy, HandleObject receiver,
         desc.value().set(vp.get());
         return defineProperty(cx, receiver, id, &desc);
     }
-    if (!getPropertyDescriptor(cx, proxy, id, &desc, JSRESOLVE_ASSIGNING))
+    if (!getPropertyDescriptor(cx, proxy, id, &desc, 0))
         return false;
     if (desc.object()) {
         // Check for read-only properties.
@@ -2601,7 +2601,7 @@ Proxy::set(JSContext *cx, HandleObject proxy, HandleObject receiver, HandleId id
     // If we have an existing (own or non-own) property with a setter, we want
     // to invoke that.
     Rooted<PropertyDescriptor> desc(cx);
-    if (!Proxy::getPropertyDescriptor(cx, proxy, id, &desc, JSRESOLVE_ASSIGNING))
+    if (!Proxy::getPropertyDescriptor(cx, proxy, id, &desc, 0))
         return false;
     if (desc.object() && desc.setter() && desc.setter() != JS_StrictPropertyStub)
         return CallSetter(cx, receiver, id, desc.setter(), desc.attributes(), strict, vp);
@@ -2969,7 +2969,7 @@ js::proxy_SetGenericAttributes(JSContext *cx, HandleObject obj, HandleId id, uns
 {
     /* Lookup the current property descriptor so we have setter/getter/value. */
     Rooted<PropertyDescriptor> desc(cx);
-    if (!Proxy::getOwnPropertyDescriptor(cx, obj, id, &desc, JSRESOLVE_ASSIGNING))
+    if (!Proxy::getOwnPropertyDescriptor(cx, obj, id, &desc, 0))
         return false;
     desc.setAttributes(*attrsp);
     return Proxy::defineProperty(cx, obj, id, &desc);

js/xpconnect/wrappers/XrayWrapper.cpp

@@ -1995,10 +1995,8 @@ XrayWrapper<Base, Traits>::defineProperty(JSContext *cx, HandleObject wrapper,
 {
     assertEnteredPolicy(cx, wrapper, id, BaseProxyHandler::SET);
 
-    // NB: We still need JSRESOLVE_ASSIGNING here for the time being, because it
-    // tells things like nodelists whether they should create the property or not.
     Rooted<JSPropertyDescriptor> existing_desc(cx);
-    if (!getOwnPropertyDescriptor(cx, wrapper, id, &existing_desc, JSRESOLVE_ASSIGNING))
+    if (!getOwnPropertyDescriptor(cx, wrapper, id, &existing_desc, 0))
         return false;
 
     if (existing_desc.object() && existing_desc.isPermanent())