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/*
* Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/AST.h>
#include <LibJS/Runtime/DeclarativeEnvironment.h>
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/GlobalObject.h>
#include <LibJS/Runtime/Reference.h>
namespace JS {
// 6.2.4.6 PutValue ( V, W ), https://tc39.es/ecma262/#sec-putvalue
ThrowCompletionOr<void> Reference::put_value(GlobalObject& global_object, Value value)
{
auto& vm = global_object.vm();
if (!is_valid_reference())
return vm.throw_completion<ReferenceError>(global_object, ErrorType::InvalidLeftHandAssignment);
if (is_unresolvable()) {
if (m_strict)
return throw_reference_error(global_object);
TRY(global_object.set(m_name, value, Object::ShouldThrowExceptions::No));
return {};
}
if (is_property_reference()) {
auto* base_obj = TRY(m_base_value.to_object(global_object));
if (is_private_reference())
return base_obj->private_set(m_private_name, value);
auto succeeded = TRY(base_obj->internal_set(m_name, value, get_this_value()));
if (!succeeded && m_strict)
return vm.throw_completion<TypeError>(global_object, ErrorType::ReferenceNullishSetProperty, m_name, m_base_value.to_string_without_side_effects());
return {};
}
VERIFY(m_base_type == BaseType::Environment);
VERIFY(m_base_environment);
if (m_environment_coordinate.has_value())
return static_cast<DeclarativeEnvironment*>(m_base_environment)->set_mutable_binding_direct(global_object, m_environment_coordinate->index, value, m_strict);
else
return m_base_environment->set_mutable_binding(global_object, m_name.as_string(), value, m_strict);
}
Completion Reference::throw_reference_error(GlobalObject& global_object) const
{
auto& vm = global_object.vm();
if (!m_name.is_valid())
return vm.throw_completion<ReferenceError>(global_object, ErrorType::ReferenceUnresolvable);
else
return vm.throw_completion<ReferenceError>(global_object, ErrorType::UnknownIdentifier, m_name.to_string_or_symbol().to_display_string());
}
// 6.2.4.5 GetValue ( V ), https://tc39.es/ecma262/#sec-getvalue
ThrowCompletionOr<Value> Reference::get_value(GlobalObject& global_object) const
{
if (!is_valid_reference() || is_unresolvable())
return throw_reference_error(global_object);
if (is_property_reference()) {
auto* base_obj = TRY(m_base_value.to_object(global_object));
if (is_private_reference())
return base_obj->private_get(m_private_name);
return base_obj->get(m_name);
}
VERIFY(m_base_type == BaseType::Environment);
VERIFY(m_base_environment);
if (m_environment_coordinate.has_value())
return static_cast<DeclarativeEnvironment*>(m_base_environment)->get_binding_value_direct(global_object, m_environment_coordinate->index, m_strict);
return m_base_environment->get_binding_value(global_object, m_name.as_string(), m_strict);
}
// 13.5.1.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-delete-operator-runtime-semantics-evaluation
ThrowCompletionOr<bool> Reference::delete_(GlobalObject& global_object)
{
// 13.5.1.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-delete-operator-runtime-semantics-evaluation
// UnaryExpression : delete UnaryExpression
// NOTE: The following steps have already been evaluated by the time we get here:
// 1. Let ref be the result of evaluating UnaryExpression.
// 2. ReturnIfAbrupt(ref).
// 3. If ref is not a Reference Record, return true.
// 4. If IsUnresolvableReference(ref) is true, then
if (is_unresolvable()) {
// a. Assert: ref.[[Strict]] is false.
VERIFY(!m_strict);
// b. Return true.
return true;
}
auto& vm = global_object.vm();
// 5. If IsPropertyReference(ref) is true, then
if (is_property_reference()) {
// a. Assert: ! IsPrivateReference(ref) is false.
VERIFY(!is_private_reference());
// b. If IsSuperReference(ref) is true, throw a ReferenceError exception.
if (is_super_reference())
return vm.throw_completion<ReferenceError>(global_object, ErrorType::UnsupportedDeleteSuperProperty);
// c. Let baseObj be ! ToObject(ref.[[Base]]).
auto* base_obj = MUST(m_base_value.to_object(global_object));
// d. Let deleteStatus be ? baseObj.[[Delete]](ref.[[ReferencedName]]).
bool delete_status = TRY(base_obj->internal_delete(m_name));
// e. If deleteStatus is false and ref.[[Strict]] is true, throw a TypeError exception.
if (!delete_status && m_strict)
return vm.throw_completion<TypeError>(global_object, ErrorType::ReferenceNullishDeleteProperty, m_name, m_base_value.to_string_without_side_effects());
// f. Return deleteStatus.
return delete_status;
}
// 6. Else,
// a. Let base be ref.[[Base]].
// b. Assert: base is an Environment Record.
VERIFY(m_base_type == BaseType::Environment);
// c. Return ? base.DeleteBinding(ref.[[ReferencedName]]).
return m_base_environment->delete_binding(global_object, m_name.as_string());
}
String Reference::to_string() const
{
StringBuilder builder;
builder.append("Reference { Base=");
switch (m_base_type) {
case BaseType::Unresolvable:
builder.append("Unresolvable");
break;
case BaseType::Environment:
builder.appendff("{}", base_environment().class_name());
break;
case BaseType::Value:
if (m_base_value.is_empty())
builder.append("<empty>");
else
builder.appendff("{}", m_base_value.to_string_without_side_effects());
break;
}
builder.append(", ReferencedName=");
if (!m_name.is_valid())
builder.append("<invalid>");
else if (m_name.is_symbol())
builder.appendff("{}", m_name.as_symbol()->to_string());
else
builder.appendff("{}", m_name.to_string());
builder.appendff(", Strict={}", m_strict);
builder.appendff(", ThisValue=");
if (m_this_value.is_empty())
builder.append("<empty>");
else
builder.appendff("{}", m_this_value.to_string_without_side_effects());
builder.append(" }");
return builder.to_string();
}
// 6.2.4.9 MakePrivateReference ( baseValue, privateIdentifier ), https://tc39.es/ecma262/#sec-makeprivatereference
Reference make_private_reference(VM& vm, Value base_value, FlyString const& private_identifier)
{
auto* private_environment = vm.running_execution_context().private_environment;
VERIFY(private_environment);
return Reference { base_value, private_environment->resolve_private_identifier(private_identifier) };
}
}
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