/dev/null

Today, I prepared for the upcoming PHP/JS conferences and had a look at the mysterious bug #883 of Google Chrome and those related to it. Also I read though SquirrelFish source, which is used by Safari 4.

The reason for the odd behavior of Chrome seems to be a if/else construct that is repeated throughout the source of runtime.cc:

// Check if the name is trivially convertible to an index and get
// the element if so.
if (name->AsArrayIndex(&index)) {
return GetElementOrCharAt(object, index);
} else {
PropertyAttributes attr;
return object->GetProperty(*name, &attr);
}


Chrome makes a difference between properties and elements. And they do weird type casts. If you check JavaScriptCore, you see there is a better way:

inline JSValue JSObject::get(ExecState* exec, const Identifier& propertyName) const
{
PropertySlot slot(this);
if (const_cast(this)->getPropertySlot(exec, propertyName, slot))
return slot.getValue(exec, propertyName);

return jsUndefined();
}