PropertyDescriptor.cpp [plain text]
#include "config.h"
#include "PropertyDescriptor.h"
#include "GetterSetter.h"
#include "JSObject.h"
#include "Operations.h"
namespace JSC {
unsigned PropertyDescriptor::defaultAttributes = (DontDelete << 1) - 1;
bool PropertyDescriptor::writable() const
{
ASSERT(!isAccessorDescriptor());
return !(m_attributes & ReadOnly);
}
bool PropertyDescriptor::enumerable() const
{
return !(m_attributes & DontEnum);
}
bool PropertyDescriptor::configurable() const
{
return !(m_attributes & DontDelete);
}
bool PropertyDescriptor::isDataDescriptor() const
{
return m_value || (m_seenAttributes & WritablePresent);
}
bool PropertyDescriptor::isGenericDescriptor() const
{
return !isAccessorDescriptor() && !isDataDescriptor();
}
bool PropertyDescriptor::isAccessorDescriptor() const
{
return m_getter || m_setter;
}
void PropertyDescriptor::setUndefined()
{
m_value = jsUndefined();
m_attributes = ReadOnly | DontDelete | DontEnum;
}
JSValue PropertyDescriptor::getter() const
{
ASSERT(isAccessorDescriptor());
return m_getter;
}
JSValue PropertyDescriptor::setter() const
{
ASSERT(isAccessorDescriptor());
return m_setter;
}
void PropertyDescriptor::setDescriptor(JSValue value, unsigned attributes)
{
ASSERT(value);
m_attributes = attributes;
if (attributes & (Getter | Setter)) {
GetterSetter* accessor = asGetterSetter(value);
m_getter = accessor->getter();
m_setter = accessor->setter();
ASSERT(m_getter || m_setter);
m_seenAttributes = EnumerablePresent | ConfigurablePresent;
m_attributes &= ~ReadOnly;
} else {
m_value = value;
m_seenAttributes = EnumerablePresent | ConfigurablePresent | WritablePresent;
}
}
void PropertyDescriptor::setAccessorDescriptor(JSValue getter, JSValue setter, unsigned attributes)
{
ASSERT(attributes & (Getter | Setter));
ASSERT(getter || setter);
m_attributes = attributes;
m_getter = getter;
m_setter = setter;
m_attributes &= ~ReadOnly;
m_seenAttributes = EnumerablePresent | ConfigurablePresent;
}
void PropertyDescriptor::setWritable(bool writable)
{
if (writable)
m_attributes &= ~ReadOnly;
else
m_attributes |= ReadOnly;
m_seenAttributes |= WritablePresent;
}
void PropertyDescriptor::setEnumerable(bool enumerable)
{
if (enumerable)
m_attributes &= ~DontEnum;
else
m_attributes |= DontEnum;
m_seenAttributes |= EnumerablePresent;
}
void PropertyDescriptor::setConfigurable(bool configurable)
{
if (configurable)
m_attributes &= ~DontDelete;
else
m_attributes |= DontDelete;
m_seenAttributes |= ConfigurablePresent;
}
void PropertyDescriptor::setSetter(JSValue setter)
{
m_setter = setter;
m_attributes |= Setter;
m_attributes &= ~ReadOnly;
}
void PropertyDescriptor::setGetter(JSValue getter)
{
m_getter = getter;
m_attributes |= Getter;
m_attributes &= ~ReadOnly;
}
bool PropertyDescriptor::equalTo(ExecState* exec, const PropertyDescriptor& other) const
{
if (!other.m_value == m_value ||
!other.m_getter == m_getter ||
!other.m_setter == m_setter)
return false;
return (!m_value || JSValue::strictEqual(exec, other.m_value, m_value)) &&
(!m_getter || JSValue::strictEqual(exec, other.m_getter, m_getter)) &&
(!m_setter || JSValue::strictEqual(exec, other.m_setter, m_setter)) &&
attributesEqual(other);
}
bool PropertyDescriptor::attributesEqual(const PropertyDescriptor& other) const
{
unsigned mismatch = other.m_attributes ^ m_attributes;
unsigned sharedSeen = other.m_seenAttributes & m_seenAttributes;
if (sharedSeen & WritablePresent && mismatch & ReadOnly)
return false;
if (sharedSeen & ConfigurablePresent && mismatch & DontDelete)
return false;
if (sharedSeen & EnumerablePresent && mismatch & DontEnum)
return false;
return true;
}
unsigned PropertyDescriptor::attributesWithOverride(const PropertyDescriptor& other) const
{
unsigned mismatch = other.m_attributes ^ m_attributes;
unsigned sharedSeen = other.m_seenAttributes & m_seenAttributes;
unsigned newAttributes = m_attributes & defaultAttributes;
if (sharedSeen & WritablePresent && mismatch & ReadOnly)
newAttributes ^= ReadOnly;
if (sharedSeen & ConfigurablePresent && mismatch & DontDelete)
newAttributes ^= DontDelete;
if (sharedSeen & EnumerablePresent && mismatch & DontEnum)
newAttributes ^= DontEnum;
return newAttributes;
}
}