/// <summary>
/// Defines or redefines the value and attributes of a property. The prototype chain is
/// not searched so if the property exists but only in the prototype chain a new property
/// will be created.
/// </summary>
/// <param name="propertyName"> The name of the property to modify. </param>
/// <param name="descriptor"> The property value and attributes. </param>
/// <param name="throwOnError"> <c>true</c> to throw an exception if the property could not
/// be set. This can happen if the property is not configurable or the object is sealed. </param>
/// <returns> <c>true</c> if the property was successfully modified; <c>false</c> otherwise. </returns>
public virtual bool DefineProperty(string propertyName, PropertyDescriptor descriptor, bool throwOnError)
{
// Retrieve info on the property.
var current = this.schema.GetPropertyIndexAndAttributes(propertyName);
if (current.Exists == false)
{
// Create a new property.
return AddProperty(propertyName, descriptor.Value, descriptor.Attributes, throwOnError);
}
// If the current property is not configurable, then the only change that is allowed is
// a change from one simple value to another (i.e. accessors are not allowed) and only
// if the writable attribute is set.
if (current.IsConfigurable == false)
{
// Get the current value of the property.
object currentValue = this.propertyValues[current.Index];
object getter = null, setter = null;
if (currentValue is PropertyAccessorValue)
{
getter = ((PropertyAccessorValue)currentValue).Getter;
setter = ((PropertyAccessorValue)currentValue).Setter;
}
// Check if the modification is allowed.
if (descriptor.Attributes != current.Attributes ||
(descriptor.IsAccessor == true && (getter != descriptor.Getter || setter != descriptor.Setter)) ||
(descriptor.IsAccessor == false && current.IsWritable == false && TypeComparer.SameValue(currentValue, descriptor.Value) == false))
{
if (throwOnError == true)
throw new JavaScriptException(this.Engine, "TypeError", string.Format("The property '{0}' is non-configurable.", propertyName));
return false;
}
}
// Set the property value and attributes.
this.schema = this.schema.SetPropertyAttributes(propertyName, descriptor.Attributes);
this.propertyValues[current.Index] = descriptor.Value;
return true;
}
/// <summary>
/// Defines or redefines the value and attributes of a property. The prototype chain is
/// not searched so if the property exists but only in the prototype chain a new property
/// will be created.
/// </summary>
/// <param name="propertyName"> The name of the property to modify. </param>
/// <param name="descriptor"> The property value and attributes. </param>
/// <param name="throwOnError"> <c>true</c> to throw an exception if the property could not
/// be set. This can happen if the property is not configurable or the object is sealed. </param>
/// <returns> <c>true</c> if the property was successfully modified; <c>false</c> otherwise. </returns>
public override bool DefineProperty(string propertyName, PropertyDescriptor descriptor, bool throwOnError)
{
// Make sure the property name isn't actually an array index.
uint arrayIndex = ParseArrayIndex(propertyName);
if (arrayIndex != uint.MaxValue)
{
// Spec violation: array elements are never accessor properties.
if (descriptor.IsAccessor == true)
{
if (throwOnError == true)
throw new JavaScriptException(this.Engine, "TypeError", string.Format("Accessors are not supported for array elements.", propertyName));
return false;
}
// Spec violation: array elements are always full access.
if (descriptor.Attributes != PropertyAttributes.FullAccess)
{
if (throwOnError == true)
throw new JavaScriptException(this.Engine, "TypeError", string.Format("Non-accessible array elements are not supported.", propertyName));
return false;
}
// The only thing that is supported is setting the value.
object value = descriptor.Value ?? Undefined.Value;
if (this.dense != null)
this.dense[arrayIndex] = value;
else
this.sparse[arrayIndex] = value;
return true;
}
// Delegate to the base class.
return base.DefineProperty(propertyName, descriptor, throwOnError);
}
/// <summary>
/// Populates the object with functions by searching a .NET type for methods marked with
/// the [JSFunction] attribute. Should be called only once at startup.
/// </summary>
/// <param name="type"> The type to search for methods. </param>
internal protected void PopulateFunctions(Type type)
{
if (type == null)
type = this.GetType();
// Group the methods on the given type by name.
var functions = new Dictionary<string, MethodGroup>(20);
var methods = type.GetMethods(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static | BindingFlags.DeclaredOnly);
foreach (var method in methods)
{
// Make sure the method has the [JSFunction] attribute.
var attribute = (JSFunctionAttribute)Attribute.GetCustomAttribute(method, typeof(JSFunctionAttribute));
if (attribute == null)
continue;
// Determine the name of the method.
string name;
if (attribute.Name != null)
{
name = Compiler.Lexer.ResolveIdentifier(this.Engine, attribute.Name);
if (name == null)
throw new InvalidOperationException(string.Format("The name provided to [JSFunction] on {0} is not a valid identifier.", method));
}
else
name = method.Name;
// Get a reference to the method group.
MethodGroup methodGroup;
if (functions.ContainsKey(name) == false)
{
methodGroup = new MethodGroup { Methods = new List<JSBinderMethod>(1), Length = -1 };
functions.Add(name, methodGroup);
}
else
methodGroup = functions[name];
// Add the method to the list.
methodGroup.Methods.Add(new JSBinderMethod(method, attribute.Flags));
// If the length doesn't equal -1, that indicates an explicit length has been set.
// Make sure it is consistant with the other methods.
if (attribute.Length >= 0)
{
if (methodGroup.Length != -1 && methodGroup.Length != attribute.Length)
throw new InvalidOperationException(string.Format("Inconsistant Length property detected on {0}.", method));
methodGroup.Length = attribute.Length;
}
}
// Now set the relevant properties on the object.
foreach (KeyValuePair<string, MethodGroup> pair in functions)
{
string name = pair.Key;
MethodGroup methodGroup = pair.Value;
// Add the function as a property of the object.
this.FastSetProperty(name, new ClrFunction(this.Engine.Function.InstancePrototype, methodGroup.Methods, name, methodGroup.Length), PropertyAttributes.NonEnumerable);
}
PropertyInfo[] properties = type.GetProperties(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static | BindingFlags.DeclaredOnly);
foreach (PropertyInfo prop in properties)
{
var attribute = Attribute.GetCustomAttribute(prop, typeof(JSPropertyAttribute), false) as JSPropertyAttribute;
if (attribute == null)
continue;
string name;
if (!string.IsNullOrEmpty(attribute.Name))
{
name = Compiler.Lexer.ResolveIdentifier(this.Engine, attribute.Name);
if (name == null)
throw new InvalidOperationException(string.Format("The name provided to [JSProperty] on {0} is not a valid identifier.", prop));
}
else
{
name = prop.Name;
}
ClrFunction getter = null, setter = null;
PropertyAttributes descriptorAttributes = PropertyAttributes.Sealed;
if (prop.CanRead)
{
var getMethod = prop.GetGetMethod(true);
getter = new ClrFunction(engine.Function.InstancePrototype, new ClrBinder(getMethod));
descriptorAttributes |= PropertyAttributes.IsAccessorProperty;
}
if (prop.CanWrite)
{
var setMethod = prop.GetSetMethod();
setter = new ClrFunction(engine.Function.InstancePrototype, new ClrBinder(setMethod));
descriptorAttributes |= PropertyAttributes.Writable;
}
if (attribute.IsEnumerable)
descriptorAttributes |= PropertyAttributes.Enumerable;
if (attribute.IsConfigurable)
descriptorAttributes |= PropertyAttributes.Configurable;
PropertyDescriptor descriptor = new PropertyDescriptor(getter, setter, descriptorAttributes);
this.DefineProperty(name, descriptor, true);
}
}
public PropertyNameAndValue(string name, PropertyDescriptor descriptor)
{
this.name = name;
this.descriptor = descriptor;
}
/// <summary>
/// Populates the object with functions by searching a .NET type for methods marked with
/// the [JSFunction] attribute. Should be called only once at startup. Also automatically
/// populates properties marked with the [JSProperty] attribute.
/// </summary>
/// <param name="type"> The type to search for methods. </param>
/// <param name="bindingFlags"> The binding flags to use to search for properties and methods. </param>
internal protected void PopulateFunctions(Type type, BindingFlags bindingFlags)
{
if (type == null)
type = this.GetType();
// Group the methods on the given type by name.
var functions = new Dictionary<string, MethodGroup>(20);
var methods = type.GetMethods(bindingFlags);
foreach (var method in methods)
{
// Make sure the method has the [JSInternalFunction] attribute.
var attribute = (JSFunctionAttribute)Attribute.GetCustomAttribute(method, typeof(JSFunctionAttribute));
if (attribute == null)
continue;
// Determine the name of the method.
string name;
if (attribute.Name != null)
name = attribute.Name;
else
name = method.Name;
// Get a reference to the method group.
MethodGroup methodGroup;
if (functions.ContainsKey(name) == false)
{
methodGroup = new MethodGroup { Methods = new List<JSBinderMethod>(1), Length = -1 };
functions.Add(name, methodGroup);
}
else
methodGroup = functions[name];
// Internal functions return nulls as undefined.
if (attribute is JSInternalFunctionAttribute)
attribute.Flags |= JSFunctionFlags.ConvertNullReturnValueToUndefined;
// Add the method to the list.
methodGroup.Methods.Add(new JSBinderMethod(method, attribute.Flags));
// If the length doesn't equal -1, that indicates an explicit length has been set.
// Make sure it is consistant with the other methods.
if (attribute.Length >= 0)
{
if (methodGroup.Length != -1 && methodGroup.Length != attribute.Length)
throw new InvalidOperationException(string.Format("Inconsistant Length property detected on {0}.", method));
methodGroup.Length = attribute.Length;
}
// Check property attributes.
var descriptorAttributes = PropertyAttributes.Sealed;
if (attribute.IsEnumerable)
descriptorAttributes |= PropertyAttributes.Enumerable;
if (attribute.IsConfigurable)
descriptorAttributes |= PropertyAttributes.Configurable;
if (attribute.IsWritable)
descriptorAttributes |= PropertyAttributes.Writable;
if (methodGroup.Methods.Count > 1 && methodGroup.PropertyAttributes != descriptorAttributes)
throw new InvalidOperationException(string.Format("Inconsistant property attributes detected on {0}.", method));
methodGroup.PropertyAttributes = descriptorAttributes;
}
// Now set the relevant properties on the object.
foreach (KeyValuePair<string, MethodGroup> pair in functions)
{
string name = pair.Key;
MethodGroup methodGroup = pair.Value;
// Add the function as a property of the object.
this.FastSetProperty(name, new ClrFunction(this.Engine.Function.InstancePrototype, methodGroup.Methods, name, methodGroup.Length), methodGroup.PropertyAttributes);
}
PropertyInfo[] properties = type.GetProperties(bindingFlags);
foreach (PropertyInfo prop in properties)
{
var attribute = Attribute.GetCustomAttribute(prop, typeof(JSPropertyAttribute), false) as JSPropertyAttribute;
if (attribute == null)
continue;
// The property name.
string name;
if (attribute.Name != null)
name = attribute.Name;
else
name = prop.Name;
// The property getter.
ClrFunction getter = null;
if (prop.CanRead)
{
var getMethod = prop.GetGetMethod(true);
getter = new ClrFunction(engine.Function.InstancePrototype, new JSBinderMethod[] { new JSBinderMethod(getMethod) }, name, 0);
}
// The property setter.
ClrFunction setter = null;
if (prop.CanWrite)
{
var setMethod = prop.GetSetMethod((bindingFlags & BindingFlags.NonPublic) != 0);
if (setMethod != null)
setter = new ClrFunction(engine.Function.InstancePrototype, new JSBinderMethod[] { new JSBinderMethod(setMethod) }, name, 1);
}
// The property attributes.
var descriptorAttributes = PropertyAttributes.Sealed;
if (attribute.IsEnumerable)
descriptorAttributes |= PropertyAttributes.Enumerable;
if (attribute.IsConfigurable)
descriptorAttributes |= PropertyAttributes.Configurable;
// Define the property.
var descriptor = new PropertyDescriptor(getter, setter, descriptorAttributes);
this.DefineProperty(name, descriptor, true);
}
}
/// <summary>
/// The idea here is to cache descriptors so that we have lightning fast performance.
/// </summary>
/// <param name="parent">The ScriptEngine that owns this ColorInstance.</param>
private static void PopulateDescriptors(ScriptEngine parent)
{
if (_descriptors != null) return;
_descriptors = new PropertyDescriptor[5];
for (int i = 0; i < 4; ++i)
{
var getter = new ColorGetter(parent, i);
var setter = new ColorSetter(parent, i);
_descriptors[i] = new PropertyDescriptor(getter, setter, PropertyAttributes.Sealed);
}
_descriptors[4] = new PropertyDescriptor(new ToStringFunc(parent, "color"), PropertyAttributes.Sealed);
}
// OBJECT SERIALIZATION AND DESERIALIZATION
//_________________________________________________________________________________________
/// <summary>
/// Creates a property descriptor from an object containing any of the following
/// properties: configurable, writable, enumerable, value, get, set.
/// </summary>
/// <param name="obj"> The object to get the property values from. </param>
/// <param name="defaults"> The values to use if the relevant value is not specified. </param>
/// <returns> A PropertyDescriptor that corresponds to the object. </returns>
public static PropertyDescriptor FromObject(ObjectInstance obj, PropertyDescriptor defaults)
{
if (obj == null)
return PropertyDescriptor.Undefined;
// Read configurable attribute.
bool configurable = defaults.IsConfigurable;
if (obj.HasProperty("configurable"))
configurable = TypeConverter.ToBoolean(obj["configurable"]);
// Read writable attribute.
bool writable = defaults.IsWritable;
if (obj.HasProperty("writable"))
writable = TypeConverter.ToBoolean(obj["writable"]);
// Read enumerable attribute.
bool enumerable = defaults.IsEnumerable;
if (obj.HasProperty("enumerable"))
enumerable = TypeConverter.ToBoolean(obj["enumerable"]);
// Read property value.
object value = defaults.Value;
if (obj.HasProperty("value"))
value = obj["value"];
// The descriptor is an accessor if get or set is present.
bool isAccessor = false;
// Read get accessor.
FunctionInstance getter = defaults.Getter;
if (obj.HasProperty("get"))
{
if (obj.HasProperty("value"))
throw new JavaScriptException(obj.Engine, "TypeError", "Property descriptors cannot have both 'get' and 'value' set");
if (obj.HasProperty("writable"))
throw new JavaScriptException(obj.Engine, "TypeError", "Property descriptors with 'get' or 'set' defined must not have 'writable' set");
if (obj["get"] is FunctionInstance)
getter = (FunctionInstance)obj["get"];
else if (TypeUtilities.IsUndefined(obj["get"]) == true)
getter = null;
else
throw new JavaScriptException(obj.Engine, "TypeError", "Property descriptor 'get' must be a function");
isAccessor = true;
}
// Read set accessor.
FunctionInstance setter = defaults.Setter;
if (obj.HasProperty("set"))
{
if (obj.HasProperty("value"))
throw new JavaScriptException(obj.Engine, "TypeError", "Property descriptors cannot have both 'set' and 'value' set");
if (obj.HasProperty("writable"))
throw new JavaScriptException(obj.Engine, "TypeError", "Property descriptors with 'get' or 'set' defined must not have 'writable' set");
if (obj["set"] is FunctionInstance)
setter = (FunctionInstance)obj["set"];
else if (TypeUtilities.IsUndefined(obj["set"]) == true)
setter = null;
else
throw new JavaScriptException(obj.Engine, "TypeError", "Property descriptor 'set' must be a function");
isAccessor = true;
}
// Build up the attributes enum.
PropertyAttributes attributes = PropertyAttributes.Sealed;
if (configurable == true)
attributes |= PropertyAttributes.Configurable;
if (writable == true)
attributes |= PropertyAttributes.Writable;
if (enumerable == true)
attributes |= PropertyAttributes.Enumerable;
// Either a value or an accessor is possible.
object descriptorValue = value;
if (isAccessor == true)
descriptorValue = new PropertyAccessorValue(getter, setter);
// Create the new property descriptor.
return new PropertyDescriptor(descriptorValue, attributes);
}
private static void PopulateDescriptors(ScriptEngine parent)
{
if (_descriptors != null) return;
_descriptors = new PropertyDescriptor[5];
_descriptors[0] = new PropertyDescriptor(new GetSizeFunc(parent), PropertyAttributes.Sealed);
_descriptors[1] = new PropertyDescriptor(new ConcatFunc(parent), PropertyAttributes.Sealed);
_descriptors[2] = new PropertyDescriptor(new SliceFunc(parent), PropertyAttributes.Sealed);
_descriptors[3] = new PropertyDescriptor(new GetSizeFunc(parent), null, PropertyAttributes.Sealed);
_descriptors[4] = new PropertyDescriptor(new ToStringFunc(parent, "bytearray"), PropertyAttributes.Sealed);
}