JSPropertyNameIterator.cpp [plain text]
#include "config.h"
#include "JSPropertyNameIterator.h"
#include "JSGlobalObject.h"
namespace JSC {
ASSERT_CLASS_FITS_IN_CELL(JSPropertyNameIterator);
inline JSPropertyNameIterator::JSPropertyNameIterator(ExecState* exec, PropertyNameArrayData* propertyNameArrayData, size_t numCacheableSlots)
: JSCell(exec->globalData().propertyNameIteratorStructure.get())
, m_cachedStructure(0)
, m_numCacheableSlots(numCacheableSlots)
, m_jsStringsSize(propertyNameArrayData->propertyNameVector().size())
, m_jsStrings(new JSValue[m_jsStringsSize])
{
PropertyNameArrayData::PropertyNameVector& propertyNameVector = propertyNameArrayData->propertyNameVector();
for (size_t i = 0; i < m_jsStringsSize; ++i)
m_jsStrings[i] = jsOwnedString(exec, propertyNameVector[i].ustring());
}
JSPropertyNameIterator::~JSPropertyNameIterator()
{
if (m_cachedStructure)
m_cachedStructure->clearEnumerationCache(this);
}
JSPropertyNameIterator* JSPropertyNameIterator::create(ExecState* exec, JSObject* o)
{
ASSERT(!o->structure()->enumerationCache() ||
o->structure()->enumerationCache()->cachedStructure() != o->structure() ||
o->structure()->enumerationCache()->cachedPrototypeChain() != o->structure()->prototypeChain(exec));
PropertyNameArray propertyNames(exec);
o->getPropertyNames(exec, propertyNames);
size_t numCacheableSlots = 0;
if (!o->structure()->hasNonEnumerableProperties() && !o->structure()->hasAnonymousSlots() &&
!o->structure()->hasGetterSetterProperties() && !o->structure()->isUncacheableDictionary() &&
!o->structure()->typeInfo().overridesGetPropertyNames())
numCacheableSlots = o->structure()->propertyStorageSize();
JSPropertyNameIterator* jsPropertyNameIterator = new (exec) JSPropertyNameIterator(exec, propertyNames.data(), numCacheableSlots);
if (o->structure()->isDictionary())
return jsPropertyNameIterator;
if (o->structure()->typeInfo().overridesGetPropertyNames())
return jsPropertyNameIterator;
size_t count = normalizePrototypeChain(exec, o);
StructureChain* structureChain = o->structure()->prototypeChain(exec);
RefPtr<Structure>* structure = structureChain->head();
for (size_t i = 0; i < count; ++i) {
if (structure[i]->typeInfo().overridesGetPropertyNames())
return jsPropertyNameIterator;
}
jsPropertyNameIterator->setCachedPrototypeChain(structureChain);
jsPropertyNameIterator->setCachedStructure(o->structure());
o->structure()->setEnumerationCache(jsPropertyNameIterator);
return jsPropertyNameIterator;
}
JSValue JSPropertyNameIterator::get(ExecState* exec, JSObject* base, size_t i)
{
JSValue& identifier = m_jsStrings[i];
if (m_cachedStructure == base->structure() && m_cachedPrototypeChain == base->structure()->prototypeChain(exec))
return identifier;
if (!base->hasProperty(exec, Identifier(exec, asString(identifier)->value(exec))))
return JSValue();
return identifier;
}
void JSPropertyNameIterator::markChildren(MarkStack& markStack)
{
markStack.appendValues(m_jsStrings.get(), m_jsStringsSize, MayContainNullValues);
}
}