LibJS: Implement most of the Reflect object

Libraries/LibJS/AST.cpp

@@ -1087,11 +1087,17 @@ PropertyName MemberExpression::computed_property_name(Interpreter& interpreter)
  auto index = m_property->execute(interpreter);
  if (interpreter.exception())
  return {};
+
  ASSERT(!index.is_empty());
- // FIXME: What about non-integer numbers tho.
- if (index.is_number() && index.to_i32() >= 0)
- return PropertyName(index.to_i32());
- return PropertyName(index.to_string());
+
+ if (!index.to_number().is_finite_number())
+ return PropertyName(index.to_string());
+
+ auto index_as_double = index.to_double();
+ if (index_as_double < 0 || (i32)index_as_double != index_as_double)
+ return PropertyName(index.to_string());
+
+ return PropertyName(index.to_i32());
 }
 
 String MemberExpression::to_string_approximation() const

Libraries/LibJS/Interpreter.cpp

@@ -208,6 +208,30 @@ Value Interpreter::call(Function& function, Value this_value, Optional<MarkedVal
  return result;
 }
 
+Value Interpreter::construct(Function& function, Function& new_target, Optional<MarkedValueList> arguments)
+{
+ auto& call_frame = push_call_frame();
+ call_frame.function_name = function.name();
+ if (arguments.has_value())
+ call_frame.arguments = arguments.value().values();
+ call_frame.environment = function.create_environment();
+
+ auto* new_object = Object::create_empty(*this, global_object());
+ auto prototype = new_target.get("prototype");
+ if (prototype.is_object())
+ new_object->set_prototype(&prototype.as_object());
+ call_frame.this_value = new_object;
+ auto result = function.construct(*this);
+
+ pop_call_frame();
+
+ if (exception())
+ return {};
+ if (result.is_object())
+ return result;
+ return new_object;
+}
+
 Value Interpreter::throw_exception(Exception* exception)
 {
  if (exception->value().is_object() && exception->value().as_object().is_error()) {

Libraries/LibJS/Interpreter.h

@@ -104,6 +104,7 @@ class Interpreter {
  void exit_scope(const ScopeNode&);
 
  Value call(Function&, Value this_value = {}, Optional<MarkedValueList> arguments = {});
+ Value construct(Function&, Function& new_target, Optional<MarkedValueList> arguments = {});
 
  CallFrame& push_call_frame()
  {

Libraries/LibJS/Makefile

@@ -39,6 +39,7 @@ OBJS = \
  Runtime/ObjectPrototype.o \
  Runtime/PrimitiveString.o \
  Runtime/Reference.o \
+ Runtime/ReflectObject.o \
  Runtime/ScriptFunction.o \
  Runtime/Shape.o \
  Runtime/StringConstructor.o \

Libraries/LibJS/Runtime/GlobalObject.cpp

@@ -49,6 +49,7 @@
 #include <LibJS/Runtime/Object.h>
 #include <LibJS/Runtime/ObjectConstructor.h>
 #include <LibJS/Runtime/ObjectPrototype.h>
+#include <LibJS/Runtime/ReflectObject.h>
 #include <LibJS/Runtime/Shape.h>
 #include <LibJS/Runtime/StringConstructor.h>
 #include <LibJS/Runtime/StringPrototype.h>
@@ -97,6 +98,7 @@ void GlobalObject::initialize()
  put("globalThis", this, attr);
  put("console", heap().allocate<ConsoleObject>(), attr);
  put("Math", heap().allocate<MathObject>(), attr);
+ put("Reflect", heap().allocate<ReflectObject>(), attr);
 
  add_constructor("Array", m_array_constructor, *m_array_prototype);
  add_constructor("Boolean", m_boolean_constructor, *m_boolean_prototype);

Libraries/LibJS/Runtime/Object.cpp

@@ -108,7 +108,7 @@ Value Object::get_own_property(const Object& this_object, const FlyString& prope
  return value_here;
 }
 
-Value Object::get_enumerable_own_properties(const Object& this_object, GetOwnPropertyMode kind) const
+Value Object::get_own_properties(const Object& this_object, GetOwnPropertyMode kind, u8 attributes) const
 {
  auto* properties_array = Array::create(interpreter().global_object());
 
@@ -152,7 +152,7 @@ Value Object::get_enumerable_own_properties(const Object& this_object, GetOwnPro
  }
 
  for (auto& it : this_object.shape().property_table_ordered()) {
- if (it.value.attributes & Attribute::Enumerable) {
+ if (it.value.attributes & attributes) {
  size_t offset = it.value.offset + property_index;
 
  if (kind == GetOwnPropertyMode::Key) {
@@ -171,13 +171,42 @@ Value Object::get_enumerable_own_properties(const Object& this_object, GetOwnPro
  return properties_array;
 }
 
+Value Object::get_own_property_descriptor(const FlyString& property_name) const
+{
+ auto metadata = shape().lookup(property_name);
+ if (!metadata.has_value())
+ return js_undefined();
+ auto value = get(property_name);
+ if (interpreter().exception())
+ return {};
+ auto* descriptor = Object::create_empty(interpreter(), interpreter().global_object());
+ descriptor->put("value", value.value_or(js_undefined()));
+ descriptor->put("writable", Value(!!(metadata.value().attributes & Attribute::Writable)));
+ descriptor->put("enumerable", Value(!!(metadata.value().attributes & Attribute::Enumerable)));
+ descriptor->put("configurable", Value(!!(metadata.value().attributes & Attribute::Configurable)));
+ return descriptor;
+}
+
 void Object::set_shape(Shape& new_shape)
 {
  m_storage.resize(new_shape.property_count());
  m_shape = &new_shape;
 }
 
-bool Object::put_own_property(Object& this_object, const FlyString& property_name, u8 attributes, Value value, PutOwnPropertyMode mode)
+bool Object::define_property(const FlyString& property_name, const Object& descriptor, bool throw_exceptions)
+{
+ auto value = descriptor.get("value");
+ u8 configurable = descriptor.get("configurable").value_or(Value(false)).to_boolean() * Attribute::Configurable;
+ u8 enumerable = descriptor.get("enumerable").value_or(Value(false)).to_boolean() * Attribute::Enumerable;
+ u8 writable = descriptor.get("writable").value_or(Value(false)).to_boolean() * Attribute::Writable;
+ u8 attributes = configurable | enumerable | writable;
+
+ dbg() << "Defining new property " << property_name << " with descriptor { " << configurable << ", " << enumerable << ", " << writable << ", attributes=" << attributes << " }";
+
+ return put_own_property(*this, property_name, attributes, value, PutOwnPropertyMode::DefineProperty, throw_exceptions);
+}
+
+bool Object::put_own_property(Object& this_object, const FlyString& property_name, u8 attributes, Value value, PutOwnPropertyMode mode, bool throw_exceptions)
 {
  auto metadata = shape().lookup(property_name);
  bool new_property = !metadata.has_value();
@@ -195,7 +224,8 @@ bool Object::put_own_property(Object& this_object, const FlyString& property_nam
 
  if (!new_property && mode == PutOwnPropertyMode::DefineProperty && !(metadata.value().attributes & Attribute::Configurable) && attributes != metadata.value().attributes) {
  dbg() << "Disallow reconfig of non-configurable property";
- interpreter().throw_exception<TypeError>(String::format("Cannot redefine property '%s'", property_name.characters()));
+ if (throw_exceptions)
+ interpreter().throw_exception<TypeError>(String::format("Cannot redefine property '%s'", property_name.characters()));
  return false;
  }
 

Libraries/LibJS/Runtime/Object.h

@@ -46,6 +46,17 @@ class Object : public Cell {
  explicit Object(Object* prototype);
  virtual ~Object();
 
+ enum class GetOwnPropertyMode {
+ Key,
+ Value,
+ KeyAndValue,
+ };
+
+ enum class PutOwnPropertyMode {
+ Put,
+ DefineProperty,
+ };
+
  Shape& shape() { return *m_shape; }
  const Shape& shape() const { return *m_shape; }
 
@@ -60,20 +71,11 @@ class Object : public Cell {
  bool put(PropertyName, Value, u8 attributes = default_attributes);
 
  Value get_own_property(const Object& this_object, const FlyString& property_name) const;
+ Value get_own_properties(const Object& this_object, GetOwnPropertyMode, u8 attributes = Attribute::Configurable | Attribute::Enumerable | Attribute::Writable) const;
+ Value get_own_property_descriptor(const FlyString& property_name) const;
 
- enum class GetOwnPropertyMode {
- Key,
- Value,
- KeyAndValue,
- };
- Value get_enumerable_own_properties(const Object& this_object, GetOwnPropertyMode) const;
-
- enum class PutOwnPropertyMode {
- Put,
- DefineProperty,
- };
-
- bool put_own_property(Object& this_object, const FlyString& property_name, u8 attributes, Value, PutOwnPropertyMode);
+ bool define_property(const FlyString& property_name, const Object& descriptor, bool throw_exceptions = true);
+ bool put_own_property(Object& this_object, const FlyString& property_name, u8 attributes, Value, PutOwnPropertyMode, bool throw_exceptions = true);
 
  bool put_native_function(const FlyString& property_name, AK::Function<Value(Interpreter&)>, i32 length = 0, u8 attribute = default_attributes);
  bool put_native_property(const FlyString& property_name, AK::Function<Value(Interpreter&)> getter, AK::Function<void(Interpreter&, Value)> setter, u8 attribute = default_attributes);

Libraries/LibJS/Runtime/ObjectConstructor.cpp

@@ -108,47 +108,23 @@ Value ObjectConstructor::set_prototype_of(Interpreter& interpreter)
 
 Value ObjectConstructor::get_own_property_descriptor(Interpreter& interpreter)
 {
- if (interpreter.argument_count() < 2)
- return interpreter.throw_exception<TypeError>("Object.getOwnPropertyDescriptor() needs 2 arguments");
- if (!interpreter.argument(0).is_object())
- return interpreter.throw_exception<TypeError>("Object argument is not an object");
- auto& object = interpreter.argument(0).as_object();
- auto metadata = object.shape().lookup(interpreter.argument(1).to_string());
- if (!metadata.has_value())
- return js_undefined();
-
- auto value = object.get(interpreter.argument(1).to_string()).value_or(js_undefined());
+ auto* object = interpreter.argument(0).to_object(interpreter.heap());
  if (interpreter.exception())
  return {};
-
- auto* descriptor = Object::create_empty(interpreter, interpreter.global_object());
- descriptor->put("configurable", Value(!!(metadata.value().attributes & Attribute::Configurable)));
- descriptor->put("enumerable", Value(!!(metadata.value().attributes & Attribute::Enumerable)));
- descriptor->put("writable", Value(!!(metadata.value().attributes & Attribute::Writable)));
- descriptor->put("value", value);
- return descriptor;
+ auto property_key = interpreter.argument(1).to_string();
+ return object->get_own_property_descriptor(property_key);
 }
 
 Value ObjectConstructor::define_property(Interpreter& interpreter)
 {
- if (interpreter.argument_count() < 3)
- return interpreter.throw_exception<TypeError>("Object.defineProperty() needs 3 arguments");
  if (!interpreter.argument(0).is_object())
  return interpreter.throw_exception<TypeError>("Object argument is not an object");
  if (!interpreter.argument(2).is_object())
  return interpreter.throw_exception<TypeError>("Descriptor argument is not an object");
  auto& object = interpreter.argument(0).as_object();
+ auto property_key = interpreter.argument(1).to_string();
  auto& descriptor = interpreter.argument(2).as_object();
-
- auto value = descriptor.get("value");
- u8 configurable = descriptor.get("configurable").value_or(Value(false)).to_boolean() * Attribute::Configurable;
- u8 enumerable = descriptor.get("enumerable").value_or(Value(false)).to_boolean() * Attribute::Enumerable;
- u8 writable = descriptor.get("writable").value_or(Value(false)).to_boolean() * Attribute::Writable;
- u8 attributes = configurable | enumerable | writable;
-
- dbg() << "Defining new property " << interpreter.argument(1).to_string() << " with descriptor { " << configurable << ", " << enumerable << ", " << writable << ", attributes=" << attributes << " }";
-
- object.put_own_property(object, interpreter.argument(1).to_string(), attributes, value, PutOwnPropertyMode::DefineProperty);
+ object.define_property(property_key, descriptor);
  return &object;
 }
 
@@ -177,7 +153,7 @@ Value ObjectConstructor::keys(Interpreter& interpreter)
  if (interpreter.exception())
  return {};
 
- return obj_arg->get_enumerable_own_properties(*obj_arg, GetOwnPropertyMode::Key);
+ return obj_arg->get_own_properties(*obj_arg, GetOwnPropertyMode::Key, Attribute::Enumerable);
 }
 
 Value ObjectConstructor::values(Interpreter& interpreter)
@@ -189,7 +165,7 @@ Value ObjectConstructor::values(Interpreter& interpreter)
  if (interpreter.exception())
  return {};
 
- return obj_arg->get_enumerable_own_properties(*obj_arg, GetOwnPropertyMode::Value);
+ return obj_arg->get_own_properties(*obj_arg, GetOwnPropertyMode::Value, Attribute::Enumerable);
 }
 
 Value ObjectConstructor::entries(Interpreter& interpreter)
@@ -201,7 +177,7 @@ Value ObjectConstructor::entries(Interpreter& interpreter)
  if (interpreter.exception())
  return {};
 
- return obj_arg->get_enumerable_own_properties(*obj_arg, GetOwnPropertyMode::KeyAndValue);
+ return obj_arg->get_own_properties(*obj_arg, GetOwnPropertyMode::KeyAndValue, Attribute::Enumerable);
 }
 
 }