/*
* Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2020-2022, Linus Groh <linusg@serenityos.org>
* Copyright (c) 2021-2022, David Tuin <davidot@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Demangle.h>
#include <AK/HashMap.h>
#include <AK/HashTable.h>
#include <AK/QuickSort.h>
#include <AK/ScopeGuard.h>
#include <AK/StringBuilder.h>
#include <AK/TemporaryChange.h>
#include <LibCrypto/BigInt/SignedBigInteger.h>
#include <LibJS/AST.h>
#include <LibJS/Heap/MarkedVector.h>
#include <LibJS/Interpreter.h>
#include <LibJS/Runtime/AbstractOperations.h>
#include <LibJS/Runtime/Accessor.h>
#include <LibJS/Runtime/Array.h>
#include <LibJS/Runtime/BigInt.h>
#include <LibJS/Runtime/ECMAScriptFunctionObject.h>
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/FunctionEnvironment.h>
#include <LibJS/Runtime/GlobalObject.h>
#include <LibJS/Runtime/IteratorOperations.h>
#include <LibJS/Runtime/NativeFunction.h>
#include <LibJS/Runtime/ObjectEnvironment.h>
#include <LibJS/Runtime/PrimitiveString.h>
#include <LibJS/Runtime/PromiseConstructor.h>
#include <LibJS/Runtime/PromiseReaction.h>
#include <LibJS/Runtime/Reference.h>
#include <LibJS/Runtime/RegExpObject.h>
#include <LibJS/Runtime/Shape.h>
#include <typeinfo>
namespace JS {
class InterpreterNodeScope {
AK_MAKE_NONCOPYABLE(InterpreterNodeScope);
AK_MAKE_NONMOVABLE(InterpreterNodeScope);
public:
InterpreterNodeScope(Interpreter& interpreter, ASTNode const& node)
: m_interpreter(interpreter)
, m_chain_node { nullptr, node }
{
m_interpreter.vm().running_execution_context().current_node = &node;
m_interpreter.push_ast_node(m_chain_node);
}
~InterpreterNodeScope()
{
m_interpreter.pop_ast_node();
}
private:
Interpreter& m_interpreter;
ExecutingASTNodeChain m_chain_node;
};
String ASTNode::class_name() const
{
// NOTE: We strip the "JS::" prefix.
return demangle(typeid(*this).name()).substring(4);
}
static void print_indent(int indent)
{
out("{}", String::repeated(' ', indent * 2));
}
static void update_function_name(Value value, FlyString const& name)
{
if (!value.is_function())
return;
auto& function = value.as_function();
if (is<ECMAScriptFunctionObject>(function) && function.name().is_empty())
static_cast<ECMAScriptFunctionObject&>(function).set_name(name);
}
static ThrowCompletionOr<String> get_function_property_name(PropertyKey key)
{
if (key.is_symbol())
return String::formatted("[{}]", key.as_symbol()->description());
return key.to_string();
}
// 14.2.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-block-runtime-semantics-evaluation
// StatementList : StatementList StatementListItem
Completion ScopeNode::evaluate_statements(Interpreter& interpreter, GlobalObject& global_object) const
{
auto completion = normal_completion({});
for (auto const& node : children()) {
completion = node.execute(interpreter, global_object).update_empty(completion.value());
if (completion.is_abrupt())
break;
}
return completion;
}
// 14.13.4 Runtime Semantics: LabelledEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-labelledevaluation
// BreakableStatement : IterationStatement
static Completion labelled_evaluation(Interpreter& interpreter, GlobalObject& global_object, IterationStatement const& statement, Vector<FlyString> const& label_set)
{
// 1. Let stmtResult be LoopEvaluation of IterationStatement with argument labelSet.
auto result = statement.loop_evaluation(interpreter, global_object, label_set);
// 2. If stmtResult.[[Type]] is break, then
if (result.type() == Completion::Type::Break) {
// a. If stmtResult.[[Target]] is empty, then
if (!result.target().has_value()) {
// i. If stmtResult.[[Value]] is empty, set stmtResult to NormalCompletion(undefined).
// ii. Else, set stmtResult to NormalCompletion(stmtResult.[[Value]]).
result = normal_completion(result.value().value_or(js_undefined()));
}
}
// 3. Return Completion(stmtResult).
return result;
}
// 14.13.4 Runtime Semantics: LabelledEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-labelledevaluation
// BreakableStatement : SwitchStatement
static Completion labelled_evaluation(Interpreter& interpreter, GlobalObject& global_object, SwitchStatement const& statement, Vector<FlyString> const&)
{
// 1. Let stmtResult be the result of evaluating SwitchStatement.
auto result = statement.execute_impl(interpreter, global_object);
// 2. If stmtResult.[[Type]] is break, then
if (result.type() == Completion::Type::Break) {
// a. If stmtResult.[[Target]] is empty, then
if (!result.target().has_value()) {
// i. If stmtResult.[[Value]] is empty, set stmtResult to NormalCompletion(undefined).
// ii. Else, set stmtResult to NormalCompletion(stmtResult.[[Value]]).
result = normal_completion(result.value().value_or(js_undefined()));
}
}
// 3. Return Completion(stmtResult).
return result;
}
// 14.13.4 Runtime Semantics: LabelledEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-labelledevaluation
// LabelledStatement : LabelIdentifier : LabelledItem
static Completion labelled_evaluation(Interpreter& interpreter, GlobalObject& global_object, LabelledStatement const& statement, Vector<FlyString> const& label_set)
{
auto const& labelled_item = *statement.labelled_item();
// 1. Let label be the StringValue of LabelIdentifier.
auto const& label = statement.label();
// 2. Let newLabelSet be the list-concatenation of labelSet and « label ».
// Optimization: Avoid vector copy if possible.
Optional<Vector<FlyString>> new_label_set;
if (is<IterationStatement>(labelled_item) || is<SwitchStatement>(labelled_item) || is<LabelledStatement>(labelled_item)) {
new_label_set = label_set;
new_label_set->append(label);
}
// 3. Let stmtResult be LabelledEvaluation of LabelledItem with argument newLabelSet.
Completion result;
if (is<IterationStatement>(labelled_item))
result = labelled_evaluation(interpreter, global_object, static_cast<IterationStatement const&>(labelled_item), *new_label_set);
else if (is<SwitchStatement>(labelled_item))
result = labelled_evaluation(interpreter, global_object, static_cast<SwitchStatement const&>(labelled_item), *new_label_set);
else if (is<LabelledStatement>(labelled_item))
result = labelled_evaluation(interpreter, global_object, static_cast<LabelledStatement const&>(labelled_item), *new_label_set);
else
result = labelled_item.execute(interpreter, global_object);
// 4. If stmtResult.[[Type]] is break and SameValue(stmtResult.[[Target]], label) is true, then
if (result.type() == Completion::Type::Break && result.target() == label) {
// a. Set stmtResult to NormalCompletion(stmtResult.[[Value]]).
result = normal_completion(result.value());
}
// 5. Return Completion(stmtResult).
return result;
}
// 14.13.3 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-labelled-statements-runtime-semantics-evaluation
Completion LabelledStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let newLabelSet be a new empty List.
// 2. Return LabelledEvaluation of this LabelledStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
void LabelledStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent + 1);
outln("(Label)");
print_indent(indent + 2);
outln("\"{}\"", m_label);
print_indent(indent + 1);
outln("(Labelled item)");
m_labelled_item->dump(indent + 2);
}
// 10.2.1.3 Runtime Semantics: EvaluateBody, https://tc39.es/ecma262/#sec-runtime-semantics-evaluatebody
Completion FunctionBody::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// Note: Scoping should have already been set up by whoever is calling this FunctionBody.
// 1. Return ? EvaluateFunctionBody of FunctionBody with arguments functionObject and argumentsList.
return evaluate_statements(interpreter, global_object);
}
// 14.2.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-block-runtime-semantics-evaluation
Completion BlockStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
Environment* old_environment { nullptr };
ArmedScopeGuard restore_environment = [&] {
vm.running_execution_context().lexical_environment = old_environment;
};
// Optimization: We only need a new lexical environment if there are any lexical declarations. :^)
if (has_lexical_declarations()) {
old_environment = vm.running_execution_context().lexical_environment;
auto* block_environment = new_declarative_environment(*old_environment);
block_declaration_instantiation(global_object, block_environment);
vm.running_execution_context().lexical_environment = block_environment;
} else {
restore_environment.disarm();
}
return evaluate_statements(interpreter, global_object);
}
Completion Program::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
return evaluate_statements(interpreter, global_object);
}
// 15.2.6 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-function-definitions-runtime-semantics-evaluation
Completion FunctionDeclaration::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
if (m_is_hoisted) {
// Perform special annexB steps see step 3 of: https://tc39.es/ecma262/#sec-web-compat-functiondeclarationinstantiation
// i. Let genv be the running execution context's VariableEnvironment.
auto* variable_environment = interpreter.vm().running_execution_context().variable_environment;
// ii. Let benv be the running execution context's LexicalEnvironment.
auto* lexical_environment = interpreter.vm().running_execution_context().lexical_environment;
// iii. Let fobj be ! benv.GetBindingValue(F, false).
auto function_object = MUST(lexical_environment->get_binding_value(global_object, name(), false));
// iv. Perform ? genv.SetMutableBinding(F, fobj, false).
TRY(variable_environment->set_mutable_binding(global_object, name(), function_object, false));
// v. Return NormalCompletion(empty).
return normal_completion({});
}
// 1. Return NormalCompletion(empty).
return normal_completion({});
}
// 15.2.6 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-function-definitions-runtime-semantics-evaluation
Completion FunctionExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return InstantiateOrdinaryFunctionExpression of FunctionExpression.
return instantiate_ordinary_function_expression(interpreter, global_object, name());
}
// 15.2.5 Runtime Semantics: InstantiateOrdinaryFunctionExpression, https://tc39.es/ecma262/#sec-runtime-semantics-instantiateordinaryfunctionexpression
Value FunctionExpression::instantiate_ordinary_function_expression(Interpreter& interpreter, GlobalObject& global_object, FlyString given_name) const
{
if (given_name.is_empty())
given_name = "";
auto has_own_name = !name().is_empty();
auto const& used_name = has_own_name ? name() : given_name;
auto* scope = interpreter.lexical_environment();
if (has_own_name) {
VERIFY(scope);
scope = new_declarative_environment(*scope);
MUST(scope->create_immutable_binding(global_object, name(), false));
}
auto* private_scope = interpreter.vm().running_execution_context().private_environment;
auto closure = ECMAScriptFunctionObject::create(global_object, used_name, source_text(), body(), parameters(), function_length(), scope, private_scope, kind(), is_strict_mode(), might_need_arguments_object(), contains_direct_call_to_eval(), is_arrow_function());
// FIXME: 6. Perform SetFunctionName(closure, name).
// FIXME: 7. Perform MakeConstructor(closure).
if (has_own_name)
MUST(scope->initialize_binding(global_object, name(), closure));
return closure;
}
// 14.4.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-empty-statement-runtime-semantics-evaluation
Completion EmptyStatement::execute(Interpreter&, GlobalObject&) const
{
// 1. Return NormalCompletion(empty).
return normal_completion({});
}
// 14.5.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-expression-statement-runtime-semantics-evaluation
Completion ExpressionStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let exprRef be the result of evaluating Expression.
// 2. Return ? GetValue(exprRef).
return m_expression->execute(interpreter, global_object);
}
// TODO: This shouldn't exist. Refactor into EvaluateCall.
ThrowCompletionOr<CallExpression::ThisAndCallee> CallExpression::compute_this_and_callee(Interpreter& interpreter, GlobalObject& global_object, Reference const& callee_reference) const
{
if (callee_reference.is_property_reference()) {
auto this_value = callee_reference.get_this_value();
auto callee = TRY(callee_reference.get_value(global_object));
return ThisAndCallee { this_value, callee };
}
// [[Call]] will handle that in non-strict mode the this value becomes the global object
return ThisAndCallee {
js_undefined(),
callee_reference.is_unresolvable()
? TRY(m_callee->execute(interpreter, global_object)).release_value()
: TRY(callee_reference.get_value(global_object))
};
}
// 13.3.8.1 Runtime Semantics: ArgumentListEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-argumentlistevaluation
static ThrowCompletionOr<void> argument_list_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<CallExpression::Argument> const& arguments, MarkedVector<Value>& list)
{
list.ensure_capacity(arguments.size());
for (auto& argument : arguments) {
auto value = TRY(argument.value->execute(interpreter, global_object)).release_value();
if (argument.is_spread) {
auto result = TRY(get_iterator_values(global_object, value, [&](Value iterator_value) -> Optional<Completion> {
list.append(iterator_value);
return {};
}));
} else {
list.append(value);
}
}
return {};
}
// 13.3.5.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-new-operator-runtime-semantics-evaluation
// 13.3.5.1.1 EvaluateNew ( constructExpr, arguments ), https://tc39.es/ecma262/#sec-evaluatenew
Completion NewExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
// 1. Let ref be the result of evaluating constructExpr.
// 2. Let constructor be ? GetValue(ref).
auto constructor = TRY(m_callee->execute(interpreter, global_object)).release_value();
// 3. If arguments is empty, let argList be a new empty List.
// 4. Else,
// a. Let argList be ? ArgumentListEvaluation of arguments.
MarkedVector<Value> arg_list(vm.heap());
TRY(argument_list_evaluation(interpreter, global_object, m_arguments, arg_list));
// 5. If IsConstructor(constructor) is false, throw a TypeError exception.
if (!constructor.is_constructor())
return throw_type_error_for_callee(interpreter, global_object, constructor, "constructor"sv);
// 6. Return ? Construct(constructor, argList).
return Value { TRY(construct(global_object, constructor.as_function(), move(arg_list))) };
}
Completion CallExpression::throw_type_error_for_callee(Interpreter& interpreter, GlobalObject& global_object, Value callee_value, StringView call_type) const
{
auto& vm = interpreter.vm();
if (is<Identifier>(*m_callee) || is<MemberExpression>(*m_callee)) {
String expression_string;
if (is<Identifier>(*m_callee)) {
expression_string = static_cast<Identifier const&>(*m_callee).string();
} else {
expression_string = static_cast<MemberExpression const&>(*m_callee).to_string_approximation();
}
return vm.throw_completion<TypeError>(global_object, ErrorType::IsNotAEvaluatedFrom, callee_value.to_string_without_side_effects(), call_type, expression_string);
} else {
return vm.throw_completion<TypeError>(global_object, ErrorType::IsNotA, callee_value.to_string_without_side_effects(), call_type);
}
}
// 13.3.6.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-function-calls-runtime-semantics-evaluation
Completion CallExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
auto callee_reference = TRY(m_callee->to_reference(interpreter, global_object));
auto [this_value, callee] = TRY(compute_this_and_callee(interpreter, global_object, callee_reference));
VERIFY(!callee.is_empty());
MarkedVector<Value> arg_list(vm.heap());
TRY(argument_list_evaluation(interpreter, global_object, m_arguments, arg_list));
if (!callee.is_function())
return throw_type_error_for_callee(interpreter, global_object, callee, "function"sv);
auto& function = callee.as_function();
if (&function == global_object.eval_function()
&& callee_reference.is_environment_reference()
&& callee_reference.name().is_string()
&& callee_reference.name().as_string() == vm.names.eval.as_string()) {
auto script_value = arg_list.size() == 0 ? js_undefined() : arg_list[0];
return perform_eval(script_value, global_object, vm.in_strict_mode() ? CallerMode::Strict : CallerMode::NonStrict, EvalMode::Direct);
}
return call(global_object, function, this_value, move(arg_list));
}
// 13.3.7.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-super-keyword-runtime-semantics-evaluation
// SuperCall : super Arguments
Completion SuperCall::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
// 1. Let newTarget be GetNewTarget().
auto new_target = vm.get_new_target();
// 2. Assert: Type(newTarget) is Object.
VERIFY(new_target.is_function());
// 3. Let func be ! GetSuperConstructor().
auto* func = get_super_constructor(interpreter.vm());
// 4. Let argList be ? ArgumentListEvaluation of Arguments.
MarkedVector<Value> arg_list(vm.heap());
TRY(argument_list_evaluation(interpreter, global_object, m_arguments, arg_list));
// 5. If IsConstructor(func) is false, throw a TypeError exception.
if (!func || !Value(func).is_constructor())
return vm.throw_completion<TypeError>(global_object, ErrorType::NotAConstructor, "Super constructor");
// 6. Let result be ? Construct(func, argList, newTarget).
auto* result = TRY(construct(global_object, static_cast<FunctionObject&>(*func), move(arg_list), &new_target.as_function()));
// 7. Let thisER be GetThisEnvironment().
auto& this_er = verify_cast<FunctionEnvironment>(get_this_environment(interpreter.vm()));
// 8. Perform ? thisER.BindThisValue(result).
TRY(this_er.bind_this_value(global_object, result));
// 9. Let F be thisER.[[FunctionObject]].
// 10. Assert: F is an ECMAScript function object.
// NOTE: This is implied by the strong C++ type.
[[maybe_unused]] auto& f = this_er.function_object();
// 11. Perform ? InitializeInstanceElements(result, F).
TRY(vm.initialize_instance_elements(*result, f));
// 12. Return result.
return Value { result };
}
// 15.5.5 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-generator-function-definitions-runtime-semantics-evaluation
Completion YieldExpression::execute(Interpreter&, GlobalObject&) const
{
// This should be transformed to a return.
VERIFY_NOT_REACHED();
}
// 15.8.5 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-async-function-definitions-runtime-semantics-evaluation
Completion AwaitExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let exprRef be the result of evaluating UnaryExpression.
// 2. Let value be ? GetValue(exprRef).
auto value = TRY(m_argument->execute(interpreter, global_object)).release_value();
// 3. Return ? Await(value).
return await(global_object, value);
}
// 14.10.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-return-statement-runtime-semantics-evaluation
Completion ReturnStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// ReturnStatement : return ;
if (!m_argument) {
// 1. Return Completion { [[Type]]: return, [[Value]]: undefined, [[Target]]: empty }.
return { Completion::Type::Return, js_undefined(), {} };
}
// ReturnStatement : return Expression ;
// 1. Let exprRef be the result of evaluating Expression.
// 2. Let exprValue be ? GetValue(exprRef).
auto value = TRY(m_argument->execute(interpreter, global_object));
// NOTE: Generators are not supported in the AST interpreter
// 3. If ! GetGeneratorKind() is async, set exprValue to ? Await(exprValue).
// 4. Return Completion { [[Type]]: return, [[Value]]: exprValue, [[Target]]: empty }.
return { Completion::Type::Return, value, {} };
}
// 14.6.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-if-statement-runtime-semantics-evaluation
Completion IfStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// IfStatement : if ( Expression ) Statement else Statement
// 1. Let exprRef be the result of evaluating Expression.
// 2. Let exprValue be ! ToBoolean(? GetValue(exprRef)).
auto predicate_result = TRY(m_predicate->execute(interpreter, global_object)).release_value();
// 3. If exprValue is true, then
if (predicate_result.to_boolean()) {
// a. Let stmtCompletion be the result of evaluating the first Statement.
// 5. Return Completion(UpdateEmpty(stmtCompletion, undefined)).
return m_consequent->execute(interpreter, global_object).update_empty(js_undefined());
}
// 4. Else,
if (m_alternate) {
// a. Let stmtCompletion be the result of evaluating the second Statement.
// 5. Return Completion(UpdateEmpty(stmtCompletion, undefined)).
return m_alternate->execute(interpreter, global_object).update_empty(js_undefined());
}
// IfStatement : if ( Expression ) Statement
// 3. If exprValue is false, then
// a. Return NormalCompletion(undefined).
return normal_completion(js_undefined());
}
// 14.11.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-with-statement-runtime-semantics-evaluation
// WithStatement : with ( Expression ) Statement
Completion WithStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let value be the result of evaluating Expression.
auto value = TRY(m_object->execute(interpreter, global_object)).release_value();
// 2. Let obj be ? ToObject(? GetValue(value)).
auto* object = TRY(value.to_object(global_object));
// 3. Let oldEnv be the running execution context's LexicalEnvironment.
auto* old_environment = interpreter.vm().running_execution_context().lexical_environment;
// 4. Let newEnv be NewObjectEnvironment(obj, true, oldEnv).
auto* new_environment = new_object_environment(*object, true, old_environment);
// 5. Set the running execution context's LexicalEnvironment to newEnv.
interpreter.vm().running_execution_context().lexical_environment = new_environment;
// 6. Let C be the result of evaluating Statement.
auto result = m_body->execute(interpreter, global_object);
// 7. Set the running execution context's LexicalEnvironment to oldEnv.
interpreter.vm().running_execution_context().lexical_environment = old_environment;
// 8. Return Completion(UpdateEmpty(C, undefined)).
return result.update_empty(js_undefined());
}
// 14.7.1.1 LoopContinues ( completion, labelSet ), https://tc39.es/ecma262/#sec-loopcontinues
static bool loop_continues(Completion const& completion, Vector<FlyString> const& label_set)
{
// 1. If completion.[[Type]] is normal, return true.
if (completion.type() == Completion::Type::Normal)
return true;
// 2. If completion.[[Type]] is not continue, return false.
if (completion.type() != Completion::Type::Continue)
return false;
// 3. If completion.[[Target]] is empty, return true.
if (!completion.target().has_value())
return true;
// 4. If completion.[[Target]] is an element of labelSet, return true.
if (label_set.contains_slow(*completion.target()))
return true;
// 5. Return false.
return false;
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : IterationStatement
Completion WhileStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// 14.7.3.2 Runtime Semantics: WhileLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-whileloopevaluation
Completion WhileStatement::loop_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<FlyString> const& label_set) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let V be undefined.
auto last_value = js_undefined();
// 2. Repeat,
for (;;) {
// a. Let exprRef be the result of evaluating Expression.
// b. Let exprValue be ? GetValue(exprRef).
auto test_result = TRY(m_test->execute(interpreter, global_object)).release_value();
// c. If ! ToBoolean(exprValue) is false, return NormalCompletion(V).
if (!test_result.to_boolean())
return normal_completion(last_value);
// d. Let stmtResult be the result of evaluating Statement.
auto body_result = m_body->execute(interpreter, global_object);
// e. If LoopContinues(stmtResult, labelSet) is false, return Completion(UpdateEmpty(stmtResult, V)).
if (!loop_continues(body_result, label_set))
return body_result.update_empty(last_value);
// f. If stmtResult.[[Value]] is not empty, set V to stmtResult.[[Value]].
if (body_result.value().has_value())
last_value = *body_result.value();
}
VERIFY_NOT_REACHED();
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : IterationStatement
Completion DoWhileStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// 14.7.2.2 Runtime Semantics: DoWhileLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-dowhileloopevaluation
Completion DoWhileStatement::loop_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<FlyString> const& label_set) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let V be undefined.
auto last_value = js_undefined();
// 2. Repeat,
for (;;) {
// a. Let stmtResult be the result of evaluating Statement.
auto body_result = m_body->execute(interpreter, global_object);
// b. If LoopContinues(stmtResult, labelSet) is false, return Completion(UpdateEmpty(stmtResult, V)).
if (!loop_continues(body_result, label_set))
return body_result.update_empty(last_value);
// c. If stmtResult.[[Value]] is not empty, set V to stmtResult.[[Value]].
if (body_result.value().has_value())
last_value = *body_result.value();
// d. Let exprRef be the result of evaluating Expression.
// e. Let exprValue be ? GetValue(exprRef).
auto test_result = TRY(m_test->execute(interpreter, global_object)).release_value();
// f. If ! ToBoolean(exprValue) is false, return NormalCompletion(V).
if (!test_result.to_boolean())
return normal_completion(last_value);
}
VERIFY_NOT_REACHED();
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : IterationStatement
Completion ForStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// 14.7.4.2 Runtime Semantics: ForLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forloopevaluation
Completion ForStatement::loop_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<FlyString> const& label_set) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// Note we don't always set a new environment but to use RAII we must do this here.
auto* old_environment = interpreter.lexical_environment();
ScopeGuard restore_old_environment = [&] {
interpreter.vm().running_execution_context().lexical_environment = old_environment;
};
size_t per_iteration_bindings_size = 0;
if (m_init) {
if (is<VariableDeclaration>(*m_init) && static_cast<VariableDeclaration const&>(*m_init).declaration_kind() != DeclarationKind::Var) {
auto* loop_environment = new_declarative_environment(*old_environment);
auto& declaration = static_cast<VariableDeclaration const&>(*m_init);
declaration.for_each_bound_name([&](auto const& name) {
if (declaration.declaration_kind() == DeclarationKind::Const) {
MUST(loop_environment->create_immutable_binding(global_object, name, true));
} else {
MUST(loop_environment->create_mutable_binding(global_object, name, false));
++per_iteration_bindings_size;
}
});
interpreter.vm().running_execution_context().lexical_environment = loop_environment;
}
(void)TRY(m_init->execute(interpreter, global_object));
}
// 14.7.4.4 CreatePerIterationEnvironment ( perIterationBindings ), https://tc39.es/ecma262/#sec-createperiterationenvironment
// NOTE: Our implementation of this AO is heavily dependent on DeclarativeEnvironment using a Vector with constant indices.
// For performance, we can take advantage of the fact that the declarations of the initialization statement are created
// in the same order each time CreatePerIterationEnvironment is invoked.
auto create_per_iteration_environment = [&]() {
// 1. If perIterationBindings has any elements, then
if (per_iteration_bindings_size == 0)
return;
// a. Let lastIterationEnv be the running execution context's LexicalEnvironment.
auto* last_iteration_env = verify_cast<DeclarativeEnvironment>(interpreter.lexical_environment());
// b. Let outer be lastIterationEnv.[[OuterEnv]].
// c. Assert: outer is not null.
VERIFY(last_iteration_env->outer_environment());
// d. Let thisIterationEnv be NewDeclarativeEnvironment(outer).
auto this_iteration_env = DeclarativeEnvironment::create_for_per_iteration_bindings({}, *last_iteration_env, per_iteration_bindings_size);
// e. For each element bn of perIterationBindings, do
// i. Perform ! thisIterationEnv.CreateMutableBinding(bn, false).
// ii. Let lastValue be ? lastIterationEnv.GetBindingValue(bn, true).
// iii. Perform ! thisIterationEnv.InitializeBinding(bn, lastValue).
//
// NOTE: This is handled by DeclarativeEnvironment::create_for_per_iteration_bindings. Step e.ii indicates it may throw,
// but that is not possible. The potential for throwing was added to accommodate support for do-expressions in the
// initialization statement, but that idea was dropped: https://github.com/tc39/ecma262/issues/299#issuecomment-172950045
// f. Set the running execution context's LexicalEnvironment to thisIterationEnv.
interpreter.vm().running_execution_context().lexical_environment = this_iteration_env;
// 2. Return undefined.
};
// 14.7.4.3 ForBodyEvaluation ( test, increment, stmt, perIterationBindings, labelSet ), https://tc39.es/ecma262/#sec-forbodyevaluation
// 1. Let V be undefined.
auto last_value = js_undefined();
// 2. Perform ? CreatePerIterationEnvironment(perIterationBindings).
create_per_iteration_environment();
// 3. Repeat,
while (true) {
// a. If test is not [empty], then
if (m_test) {
// i. Let testRef be the result of evaluating test.
// ii. Let testValue be ? GetValue(testRef).
auto test_value = TRY(m_test->execute(interpreter, global_object)).release_value();
// iii. If ! ToBoolean(testValue) is false, return NormalCompletion(V).
if (!test_value.to_boolean())
return normal_completion(last_value);
}
// b. Let result be the result of evaluating stmt.
auto result = m_body->execute(interpreter, global_object);
// c. If LoopContinues(result, labelSet) is false, return Completion(UpdateEmpty(result, V)).
if (!loop_continues(result, label_set))
return result.update_empty(last_value);
// d. If result.[[Value]] is not empty, set V to result.[[Value]].
if (result.value().has_value())
last_value = *result.value();
// e. Perform ? CreatePerIterationEnvironment(perIterationBindings).
create_per_iteration_environment();
// f. If increment is not [empty], then
if (m_update) {
// i. Let incRef be the result of evaluating increment.
// ii. Perform ? GetValue(incRef).
(void)TRY(m_update->execute(interpreter, global_object));
}
}
VERIFY_NOT_REACHED();
}
struct ForInOfHeadState {
explicit ForInOfHeadState(Variant<NonnullRefPtr<ASTNode>, NonnullRefPtr<BindingPattern>> lhs)
{
lhs.visit(
[&](NonnullRefPtr<ASTNode>& ast_node) {
expression_lhs = ast_node.ptr();
},
[&](NonnullRefPtr<BindingPattern>& pattern) {
pattern_lhs = pattern.ptr();
destructuring = true;
lhs_kind = Assignment;
});
}
ASTNode* expression_lhs = nullptr;
BindingPattern* pattern_lhs = nullptr;
enum LhsKind {
Assignment,
VarBinding,
LexicalBinding
};
LhsKind lhs_kind = Assignment;
bool destructuring = false;
Value rhs_value;
// 14.7.5.7 ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind, lhsKind, labelSet [ , iteratorKind ] ), https://tc39.es/ecma262/#sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
// Note: This is only steps 6.g through 6.j of the method because we currently implement for-in without an iterator so to prevent duplicated code we do this part here.
ThrowCompletionOr<void> execute_head(Interpreter& interpreter, GlobalObject& global_object, Value next_value) const
{
VERIFY(!next_value.is_empty());
Optional<Reference> lhs_reference;
Environment* iteration_environment = nullptr;
// g. If lhsKind is either assignment or varBinding, then
if (lhs_kind == Assignment || lhs_kind == VarBinding) {
if (!destructuring) {
VERIFY(expression_lhs);
if (is<VariableDeclaration>(*expression_lhs)) {
auto& declaration = static_cast<VariableDeclaration const&>(*expression_lhs);
VERIFY(declaration.declarations().first().target().has<NonnullRefPtr<Identifier>>());
lhs_reference = TRY(declaration.declarations().first().target().get<NonnullRefPtr<Identifier>>()->to_reference(interpreter, global_object));
} else {
VERIFY(is<Identifier>(*expression_lhs) || is<MemberExpression>(*expression_lhs) || is<CallExpression>(*expression_lhs));
auto& expression = static_cast<Expression const&>(*expression_lhs);
lhs_reference = TRY(expression.to_reference(interpreter, global_object));
}
}
}
// h. Else,
else {
VERIFY(expression_lhs && is<VariableDeclaration>(*expression_lhs));
iteration_environment = new_declarative_environment(*interpreter.lexical_environment());
auto& for_declaration = static_cast<VariableDeclaration const&>(*expression_lhs);
for_declaration.for_each_bound_name([&](auto const& name) {
if (for_declaration.declaration_kind() == DeclarationKind::Const)
MUST(iteration_environment->create_immutable_binding(global_object, name, false));
else
MUST(iteration_environment->create_mutable_binding(global_object, name, true));
});
interpreter.vm().running_execution_context().lexical_environment = iteration_environment;
if (!destructuring) {
VERIFY(for_declaration.declarations().first().target().has<NonnullRefPtr<Identifier>>());
lhs_reference = MUST(interpreter.vm().resolve_binding(for_declaration.declarations().first().target().get<NonnullRefPtr<Identifier>>()->string()));
}
}
// i. If destructuring is false, then
if (!destructuring) {
VERIFY(lhs_reference.has_value());
if (lhs_kind == LexicalBinding)
return lhs_reference->initialize_referenced_binding(global_object, next_value);
else
return lhs_reference->put_value(global_object, next_value);
}
// j. Else,
if (lhs_kind == Assignment) {
VERIFY(pattern_lhs);
return interpreter.vm().destructuring_assignment_evaluation(*pattern_lhs, next_value, global_object);
}
VERIFY(expression_lhs && is<VariableDeclaration>(*expression_lhs));
auto& for_declaration = static_cast<VariableDeclaration const&>(*expression_lhs);
auto& binding_pattern = for_declaration.declarations().first().target().get<NonnullRefPtr<BindingPattern>>();
VERIFY(lhs_kind == VarBinding || iteration_environment);
// At this point iteration_environment is undefined if lhs_kind == VarBinding which means this does both
// branch j.ii and j.iii because ForBindingInitialization is just a forwarding call to BindingInitialization.
return interpreter.vm().binding_initialization(binding_pattern, next_value, iteration_environment, global_object);
}
};
// 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation
// 14.7.5.6 ForIn/OfHeadEvaluation ( uninitializedBoundNames, expr, iterationKind ), https://tc39.es/ecma262/#sec-runtime-semantics-forinofheadevaluation
// This method combines ForInOfLoopEvaluation and ForIn/OfHeadEvaluation for similar reason as ForIn/OfBodyEvaluation, to prevent code duplication.
// For the same reason we also skip step 6 and 7 of ForIn/OfHeadEvaluation as this is done by the appropriate for loop type.
static ThrowCompletionOr<ForInOfHeadState> for_in_of_head_execute(Interpreter& interpreter, GlobalObject& global_object, Variant<NonnullRefPtr<ASTNode>, NonnullRefPtr<BindingPattern>> lhs, Expression const& rhs)
{
ForInOfHeadState state(lhs);
if (auto* ast_ptr = lhs.get_pointer<NonnullRefPtr<ASTNode>>(); ast_ptr && is<VariableDeclaration>(*(*ast_ptr))) {
// Runtime Semantics: ForInOfLoopEvaluation, for any of:
// ForInOfStatement : for ( var ForBinding in Expression ) Statement
// ForInOfStatement : for ( ForDeclaration in Expression ) Statement
// ForInOfStatement : for ( var ForBinding of AssignmentExpression ) Statement
// ForInOfStatement : for ( ForDeclaration of AssignmentExpression ) Statement
// 14.7.5.6 ForIn/OfHeadEvaluation ( uninitializedBoundNames, expr, iterationKind ), https://tc39.es/ecma262/#sec-runtime-semantics-forinofheadevaluation
Environment* new_environment = nullptr;
auto& variable_declaration = static_cast<VariableDeclaration const&>(*(*ast_ptr));
VERIFY(variable_declaration.declarations().size() == 1);
state.destructuring = variable_declaration.declarations().first().target().has<NonnullRefPtr<BindingPattern>>();
if (variable_declaration.declaration_kind() == DeclarationKind::Var) {
state.lhs_kind = ForInOfHeadState::VarBinding;
auto& variable = variable_declaration.declarations().first();
// B.3.5 Initializers in ForIn Statement Heads, https://tc39.es/ecma262/#sec-initializers-in-forin-statement-heads
if (variable.init()) {
VERIFY(variable.target().has<NonnullRefPtr<Identifier>>());
auto& binding_id = variable.target().get<NonnullRefPtr<Identifier>>()->string();
auto reference = TRY(interpreter.vm().resolve_binding(binding_id));
auto result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(global_object, *variable.init(), binding_id));
TRY(reference.put_value(global_object, result));
}
} else {
state.lhs_kind = ForInOfHeadState::LexicalBinding;
new_environment = new_declarative_environment(*interpreter.lexical_environment());
variable_declaration.for_each_bound_name([&](auto const& name) {
MUST(new_environment->create_mutable_binding(global_object, name, false));
});
}
if (new_environment) {
// 2.d Set the running execution context's LexicalEnvironment to newEnv.
TemporaryChange<Environment*> scope_change(interpreter.vm().running_execution_context().lexical_environment, new_environment);
// 3. Let exprRef be the result of evaluating expr.
// 5. Let exprValue be ? GetValue(exprRef).
state.rhs_value = TRY(rhs.execute(interpreter, global_object)).release_value();
// Note that since a reference stores its environment it doesn't matter we only reset
// this after step 5. (Also we have no way of separating these steps at this point)
// 4. Set the running execution context's LexicalEnvironment to oldEnv.
} else {
// 3. Let exprRef be the result of evaluating expr.
// 5. Let exprValue be ? GetValue(exprRef).
state.rhs_value = TRY(rhs.execute(interpreter, global_object)).release_value();
}
return state;
}
// Runtime Semantics: ForInOfLoopEvaluation, for any of:
// ForInOfStatement : for ( LeftHandSideExpression in Expression ) Statement
// ForInOfStatement : for ( LeftHandSideExpression of AssignmentExpression ) Statement
// 14.7.5.6 ForIn/OfHeadEvaluation ( uninitializedBoundNames, expr, iterationKind ), https://tc39.es/ecma262/#sec-runtime-semantics-forinofheadevaluation
// We can skip step 1, 2 and 4 here (on top of already skipping step 6 and 7).
// 3. Let exprRef be the result of evaluating expr.
// 5. Let exprValue be ? GetValue(exprRef).
state.rhs_value = TRY(rhs.execute(interpreter, global_object)).release_value();
return state;
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : IterationStatement
Completion ForInStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation
Completion ForInStatement::loop_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<FlyString> const& label_set) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto for_in_head_state = TRY(for_in_of_head_execute(interpreter, global_object, m_lhs, *m_rhs));
auto rhs_result = for_in_head_state.rhs_value;
// 14.7.5.6 ForIn/OfHeadEvaluation ( uninitializedBoundNames, expr, iterationKind ), https://tc39.es/ecma262/#sec-runtime-semantics-forinofheadevaluation
// a. If exprValue is undefined or null, then
if (rhs_result.is_nullish()) {
// i. Return Completion { [[Type]]: break, [[Value]]: empty, [[Target]]: empty }.
return { Completion::Type::Break, {}, {} };
}
// b. Let obj be ! ToObject(exprValue).
auto* object = MUST(rhs_result.to_object(global_object));
// 14.7.5.7 ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind, lhsKind, labelSet [ , iteratorKind ] ), https://tc39.es/ecma262/#sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
// 2. Let oldEnv be the running execution context's LexicalEnvironment.
Environment* old_environment = interpreter.lexical_environment();
auto restore_scope = ScopeGuard([&] {
interpreter.vm().running_execution_context().lexical_environment = old_environment;
});
// 3. Let V be undefined.
auto last_value = js_undefined();
auto result = object->enumerate_object_properties([&](auto value) -> Optional<Completion> {
TRY(for_in_head_state.execute_head(interpreter, global_object, value));
// l. Let result be the result of evaluating stmt.
auto result = m_body->execute(interpreter, global_object);
// m. Set the running execution context's LexicalEnvironment to oldEnv.
interpreter.vm().running_execution_context().lexical_environment = old_environment;
// n. If LoopContinues(result, labelSet) is false, then
if (!loop_continues(result, label_set)) {
// 1. Return Completion(UpdateEmpty(result, V)).
return result.update_empty(last_value);
}
// o. If result.[[Value]] is not empty, set V to result.[[Value]].
if (result.value().has_value())
last_value = *result.value();
return {};
});
return result.value_or(last_value);
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : IterationStatement
Completion ForOfStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation
Completion ForOfStatement::loop_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<FlyString> const& label_set) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto for_of_head_state = TRY(for_in_of_head_execute(interpreter, global_object, m_lhs, m_rhs));
auto rhs_result = for_of_head_state.rhs_value;
// 14.7.5.7 ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind, lhsKind, labelSet [ , iteratorKind ] ), https://tc39.es/ecma262/#sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
// We use get_iterator_values which behaves like ForIn/OfBodyEvaluation with iteratorKind iterate.
// 2. Let oldEnv be the running execution context's LexicalEnvironment.
Environment* old_environment = interpreter.lexical_environment();
auto restore_scope = ScopeGuard([&] {
interpreter.vm().running_execution_context().lexical_environment = old_environment;
});
// 3. Let V be undefined.
auto last_value = js_undefined();
Optional<Completion> status;
(void)TRY(get_iterator_values(global_object, rhs_result, [&](Value value) -> Optional<Completion> {
TRY(for_of_head_state.execute_head(interpreter, global_object, value));
// l. Let result be the result of evaluating stmt.
auto result = m_body->execute(interpreter, global_object);
// m. Set the running execution context's LexicalEnvironment to oldEnv.
interpreter.vm().running_execution_context().lexical_environment = old_environment;
// n. If LoopContinues(result, labelSet) is false, then
if (!loop_continues(result, label_set)) {
// 2. Set status to UpdateEmpty(result, V).
status = result.update_empty(last_value);
// 4. Return ? IteratorClose(iteratorRecord, status).
// NOTE: This is done by returning a completion from the callback.
return status;
}
// o. If result.[[Value]] is not empty, set V to result.[[Value]].
if (result.value().has_value())
last_value = *result.value();
return {};
}));
// Return `status` set during step n.2. in the callback, or...
// e. If done is true, return NormalCompletion(V).
return status.value_or(normal_completion(last_value));
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : IterationStatement
Completion ForAwaitOfStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation
Completion ForAwaitOfStatement::loop_evaluation(Interpreter& interpreter, GlobalObject& global_object, Vector<FlyString> const& label_set) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 14.7.5.6 ForIn/OfHeadEvaluation ( uninitializedBoundNames, expr, iterationKind ), https://tc39.es/ecma262/#sec-runtime-semantics-forinofheadevaluation
// Note: Performs only steps 1 through 5.
auto for_of_head_state = TRY(for_in_of_head_execute(interpreter, global_object, m_lhs, m_rhs));
auto rhs_result = for_of_head_state.rhs_value;
// NOTE: Perform step 7 from ForIn/OfHeadEvaluation. And since this is always async we only have to do step 7.d.
// d. Return ? GetIterator(exprValue, iteratorHint).
auto iterator = TRY(get_iterator(global_object, rhs_result, IteratorHint::Async));
auto& vm = interpreter.vm();
// 14.7.5.7 ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind, lhsKind, labelSet [ , iteratorKind ] ), https://tc39.es/ecma262/#sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
// NOTE: Here iteratorKind is always async.
// 2. Let oldEnv be the running execution context's LexicalEnvironment.
Environment* old_environment = interpreter.lexical_environment();
auto restore_scope = ScopeGuard([&] {
interpreter.vm().running_execution_context().lexical_environment = old_environment;
});
// 3. Let V be undefined.
auto last_value = js_undefined();
// NOTE: Step 4 and 5 are just extracting properties from the head which is done already in for_in_of_head_execute.
// And these are only used in step 6.g through 6.k which is done with for_of_head_state.execute_head.
// 6. Repeat,
while (true) {
// a. Let nextResult be ? Call(iteratorRecord.[[NextMethod]], iteratorRecord.[[Iterator]]).
auto next_result = TRY(call(global_object, iterator.next_method, iterator.iterator));
// b. If iteratorKind is async, set nextResult to ? Await(nextResult).
next_result = TRY(await(global_object, next_result));
// c. If Type(nextResult) is not Object, throw a TypeError exception.
if (!next_result.is_object())
return vm.throw_completion<TypeError>(global_object, ErrorType::IterableNextBadReturn);
// d. Let done be ? IteratorComplete(nextResult).
auto done = TRY(iterator_complete(global_object, next_result.as_object()));
// e. If done is true, return NormalCompletion(V).
if (done)
return last_value;
// f. Let nextValue be ? IteratorValue(nextResult).
auto next_value = TRY(iterator_value(global_object, next_result.as_object()));
// NOTE: This performs steps g. through to k.
TRY(for_of_head_state.execute_head(interpreter, global_object, next_value));
// l. Let result be the result of evaluating stmt.
auto result = m_body->execute(interpreter, global_object);
// m. Set the running execution context's LexicalEnvironment to oldEnv.
interpreter.vm().running_execution_context().lexical_environment = old_environment;
// n. If LoopContinues(result, labelSet) is false, then
if (!loop_continues(result, label_set)) {
// 2. Set status to UpdateEmpty(result, V).
auto status = result.update_empty(last_value);
// 3. If iteratorKind is async, return ? AsyncIteratorClose(iteratorRecord, status).
return async_iterator_close(global_object, iterator, move(status));
}
// o. If result.[[Value]] is not empty, set V to result.[[Value]].
if (result.value().has_value())
last_value = *result.value();
}
VERIFY_NOT_REACHED();
}
// 13.6.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-exp-operator-runtime-semantics-evaluation
// 13.7.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-multiplicative-operators-runtime-semantics-evaluation
// 13.8.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-addition-operator-plus-runtime-semantics-evaluation
// 13.8.2.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-subtraction-operator-minus-runtime-semantics-evaluation
// 13.9.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-left-shift-operator-runtime-semantics-evaluation
// 13.9.2.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-signed-right-shift-operator-runtime-semantics-evaluation
// 13.9.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-unsigned-right-shift-operator-runtime-semantics-evaluation
// 13.10.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-relational-operators-runtime-semantics-evaluation
// 13.11.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-equality-operators-runtime-semantics-evaluation
Completion BinaryExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// Special case in which we cannot execute the lhs. RelationalExpression : PrivateIdentifier in ShiftExpression
// RelationalExpression : PrivateIdentifier in ShiftExpression, https://tc39.es/ecma262/#sec-relational-operators-runtime-semantics-evaluation
if (m_op == BinaryOp::In && is<PrivateIdentifier>(*m_lhs)) {
auto& private_identifier = static_cast<PrivateIdentifier const&>(*m_lhs).string();
auto rhs_result = TRY(m_rhs->execute(interpreter, global_object)).release_value();
if (!rhs_result.is_object())
return interpreter.vm().throw_completion<TypeError>(global_object, ErrorType::InOperatorWithObject);
auto* private_environment = interpreter.vm().running_execution_context().private_environment;
VERIFY(private_environment);
auto private_name = private_environment->resolve_private_identifier(private_identifier);
return Value(rhs_result.as_object().private_element_find(private_name) != nullptr);
}
auto lhs_result = TRY(m_lhs->execute(interpreter, global_object)).release_value();
auto rhs_result = TRY(m_rhs->execute(interpreter, global_object)).release_value();
switch (m_op) {
case BinaryOp::Addition:
return TRY(add(global_object, lhs_result, rhs_result));
case BinaryOp::Subtraction:
return TRY(sub(global_object, lhs_result, rhs_result));
case BinaryOp::Multiplication:
return TRY(mul(global_object, lhs_result, rhs_result));
case BinaryOp::Division:
return TRY(div(global_object, lhs_result, rhs_result));
case BinaryOp::Modulo:
return TRY(mod(global_object, lhs_result, rhs_result));
case BinaryOp::Exponentiation:
return TRY(exp(global_object, lhs_result, rhs_result));
case BinaryOp::StrictlyEquals:
return Value(is_strictly_equal(lhs_result, rhs_result));
case BinaryOp::StrictlyInequals:
return Value(!is_strictly_equal(lhs_result, rhs_result));
case BinaryOp::LooselyEquals:
return Value(TRY(is_loosely_equal(global_object, lhs_result, rhs_result)));
case BinaryOp::LooselyInequals:
return Value(!TRY(is_loosely_equal(global_object, lhs_result, rhs_result)));
case BinaryOp::GreaterThan:
return TRY(greater_than(global_object, lhs_result, rhs_result));
case BinaryOp::GreaterThanEquals:
return TRY(greater_than_equals(global_object, lhs_result, rhs_result));
case BinaryOp::LessThan:
return TRY(less_than(global_object, lhs_result, rhs_result));
case BinaryOp::LessThanEquals:
return TRY(less_than_equals(global_object, lhs_result, rhs_result));
case BinaryOp::BitwiseAnd:
return TRY(bitwise_and(global_object, lhs_result, rhs_result));
case BinaryOp::BitwiseOr:
return TRY(bitwise_or(global_object, lhs_result, rhs_result));
case BinaryOp::BitwiseXor:
return TRY(bitwise_xor(global_object, lhs_result, rhs_result));
case BinaryOp::LeftShift:
return TRY(left_shift(global_object, lhs_result, rhs_result));
case BinaryOp::RightShift:
return TRY(right_shift(global_object, lhs_result, rhs_result));
case BinaryOp::UnsignedRightShift:
return TRY(unsigned_right_shift(global_object, lhs_result, rhs_result));
case BinaryOp::In:
return TRY(in(global_object, lhs_result, rhs_result));
case BinaryOp::InstanceOf:
return TRY(instance_of(global_object, lhs_result, rhs_result));
}
VERIFY_NOT_REACHED();
}
// 13.13.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-binary-logical-operators-runtime-semantics-evaluation
Completion LogicalExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let lref be the result of evaluating <Expression>.
// 2. Let lval be ? GetValue(lref).
auto lhs_result = TRY(m_lhs->execute(interpreter, global_object)).release_value();
switch (m_op) {
// LogicalANDExpression : LogicalANDExpression && BitwiseORExpression
case LogicalOp::And:
// 3. Let lbool be ! ToBoolean(lval).
// 4. If lbool is false, return lval.
if (!lhs_result.to_boolean())
return lhs_result;
// 5. Let rref be the result of evaluating BitwiseORExpression.
// 6. Return ? GetValue(rref).
return m_rhs->execute(interpreter, global_object);
// LogicalORExpression : LogicalORExpression || LogicalANDExpression
case LogicalOp::Or:
// 3. Let lbool be ! ToBoolean(lval).
// 4. If lbool is true, return lval.
if (lhs_result.to_boolean())
return lhs_result;
// 5. Let rref be the result of evaluating LogicalANDExpression.
// 6. Return ? GetValue(rref).
return m_rhs->execute(interpreter, global_object);
// CoalesceExpression : CoalesceExpressionHead ?? BitwiseORExpression
case LogicalOp::NullishCoalescing:
// 3. If lval is undefined or null, then
if (lhs_result.is_nullish()) {
// a. Let rref be the result of evaluating BitwiseORExpression.
// b. Return ? GetValue(rref).
return m_rhs->execute(interpreter, global_object);
}
// 4. Otherwise, return lval.
return lhs_result;
}
VERIFY_NOT_REACHED();
}
ThrowCompletionOr<Reference> Expression::to_reference(Interpreter&, GlobalObject&) const
{
return Reference {};
}
ThrowCompletionOr<Reference> Identifier::to_reference(Interpreter& interpreter, GlobalObject&) const
{
if (m_cached_environment_coordinate.has_value()) {
auto* environment = interpreter.vm().running_execution_context().lexical_environment;
for (size_t i = 0; i < m_cached_environment_coordinate->hops; ++i)
environment = environment->outer_environment();
VERIFY(environment);
VERIFY(environment->is_declarative_environment());
if (!environment->is_permanently_screwed_by_eval()) {
return Reference { *environment, string(), interpreter.vm().in_strict_mode(), m_cached_environment_coordinate };
}
m_cached_environment_coordinate = {};
}
auto reference = TRY(interpreter.vm().resolve_binding(string()));
if (reference.environment_coordinate().has_value())
m_cached_environment_coordinate = reference.environment_coordinate();
return reference;
}
ThrowCompletionOr<Reference> MemberExpression::to_reference(Interpreter& interpreter, GlobalObject& global_object) const
{
// 13.3.7.1 Runtime Semantics: Evaluation
// SuperProperty : super [ Expression ]
// SuperProperty : super . IdentifierName
// https://tc39.es/ecma262/#sec-super-keyword-runtime-semantics-evaluation
if (is<SuperExpression>(object())) {
// 1. Let env be GetThisEnvironment().
auto& environment = get_this_environment(interpreter.vm());
// 2. Let actualThis be ? env.GetThisBinding().
auto actual_this = TRY(environment.get_this_binding(global_object));
PropertyKey property_key;
if (is_computed()) {
// SuperProperty : super [ Expression ]
// 3. Let propertyNameReference be the result of evaluating Expression.
// 4. Let propertyNameValue be ? GetValue(propertyNameReference).
auto property_name_value = TRY(m_property->execute(interpreter, global_object)).release_value();
// 5. Let propertyKey be ? ToPropertyKey(propertyNameValue).
property_key = TRY(property_name_value.to_property_key(global_object));
} else {
// SuperProperty : super . IdentifierName
// 3. Let propertyKey be StringValue of IdentifierName.
VERIFY(is<Identifier>(property()));
property_key = static_cast<Identifier const&>(property()).string();
}
// 6. If the code matched by this SuperProperty is strict mode code, let strict be true; else let strict be false.
bool strict = interpreter.vm().in_strict_mode();
// 7. Return ? MakeSuperPropertyReference(actualThis, propertyKey, strict).
return TRY(make_super_property_reference(global_object, actual_this, property_key, strict));
}
auto base_reference = TRY(m_object->to_reference(interpreter, global_object));
Value base_value;
if (base_reference.is_valid_reference())
base_value = TRY(base_reference.get_value(global_object));
else
base_value = TRY(m_object->execute(interpreter, global_object)).release_value();
VERIFY(!base_value.is_empty());
// From here on equivalent to
// 13.3.4 EvaluatePropertyAccessWithIdentifierKey ( baseValue, identifierName, strict ), https://tc39.es/ecma262/#sec-evaluate-property-access-with-identifier-key
PropertyKey property_key;
if (is_computed()) {
// Weird order which I can't quite find from the specs.
auto value = TRY(m_property->execute(interpreter, global_object)).release_value();
VERIFY(!value.is_empty());
TRY(require_object_coercible(global_object, base_value));
property_key = TRY(PropertyKey::from_value(global_object, value));
} else if (is<PrivateIdentifier>(*m_property)) {
auto& private_identifier = static_cast<PrivateIdentifier const&>(*m_property);
return make_private_reference(interpreter.vm(), base_value, private_identifier.string());
} else {
property_key = verify_cast<Identifier>(*m_property).string();
TRY(require_object_coercible(global_object, base_value));
}
if (!property_key.is_valid())
return Reference {};
auto strict = interpreter.vm().in_strict_mode();
return Reference { base_value, move(property_key), {}, strict };
}
// 13.5.1.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-delete-operator-runtime-semantics-evaluation
// 13.5.2.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-void-operator-runtime-semantics-evaluation
// 13.5.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-typeof-operator-runtime-semantics-evaluation
// 13.5.4.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-unary-plus-operator-runtime-semantics-evaluation
// 13.5.5.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-unary-minus-operator-runtime-semantics-evaluation
// 13.5.6.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-bitwise-not-operator-runtime-semantics-evaluation
// 13.5.7.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-logical-not-operator-runtime-semantics-evaluation
Completion UnaryExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
if (m_op == UnaryOp::Delete) {
auto reference = TRY(m_lhs->to_reference(interpreter, global_object));
return Value(TRY(reference.delete_(global_object)));
}
Value lhs_result;
if (m_op == UnaryOp::Typeof && is<Identifier>(*m_lhs)) {
auto reference = TRY(m_lhs->to_reference(interpreter, global_object));
if (reference.is_unresolvable())
lhs_result = js_undefined();
else
lhs_result = TRY(reference.get_value(global_object));
VERIFY(!lhs_result.is_empty());
} else {
// 1. Let expr be the result of evaluating UnaryExpression.
lhs_result = TRY(m_lhs->execute(interpreter, global_object)).release_value();
}
switch (m_op) {
case UnaryOp::BitwiseNot:
return TRY(bitwise_not(global_object, lhs_result));
case UnaryOp::Not:
return Value(!lhs_result.to_boolean());
case UnaryOp::Plus:
return TRY(unary_plus(global_object, lhs_result));
case UnaryOp::Minus:
return TRY(unary_minus(global_object, lhs_result));
case UnaryOp::Typeof:
return Value { js_string(vm, lhs_result.typeof()) };
case UnaryOp::Void:
return js_undefined();
case UnaryOp::Delete:
VERIFY_NOT_REACHED();
}
VERIFY_NOT_REACHED();
}
Completion SuperExpression::execute(Interpreter&, GlobalObject&) const
{
// The semantics for SuperExpression are handled in CallExpression and SuperCall.
VERIFY_NOT_REACHED();
}
Completion ClassElement::execute(Interpreter&, GlobalObject&) const
{
// Note: The semantics of class element are handled in class_element_evaluation
VERIFY_NOT_REACHED();
}
static ThrowCompletionOr<ClassElement::ClassElementName> class_key_to_property_name(Interpreter& interpreter, GlobalObject& global_object, Expression const& key)
{
if (is<PrivateIdentifier>(key)) {
auto& private_identifier = static_cast<PrivateIdentifier const&>(key);
auto* private_environment = interpreter.vm().running_execution_context().private_environment;
VERIFY(private_environment);
return ClassElement::ClassElementName { private_environment->resolve_private_identifier(private_identifier.string()) };
}
auto prop_key = TRY(key.execute(interpreter, global_object)).release_value();
if (prop_key.is_object())
prop_key = TRY(prop_key.to_primitive(global_object, Value::PreferredType::String));
auto property_key = TRY(PropertyKey::from_value(global_object, prop_key));
return ClassElement::ClassElementName { property_key };
}
// 15.4.5 Runtime Semantics: MethodDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-methoddefinitionevaluation
ThrowCompletionOr<ClassElement::ClassValue> ClassMethod::class_element_evaluation(Interpreter& interpreter, GlobalObject& global_object, Object& target) const
{
auto property_key_or_private_name = TRY(class_key_to_property_name(interpreter, global_object, *m_key));
auto method_value = TRY(m_function->execute(interpreter, global_object)).release_value();
auto function_handle = make_handle(&method_value.as_function());
auto& method_function = static_cast<ECMAScriptFunctionObject&>(method_value.as_function());
method_function.make_method(target);
auto set_function_name = [&](String prefix = "") {
auto name = property_key_or_private_name.visit(
[&](PropertyKey const& property_key) -> String {
if (property_key.is_symbol()) {
auto description = property_key.as_symbol()->description();
if (description.is_empty())
return "";
return String::formatted("[{}]", description);
} else {
return property_key.to_string();
}
},
[&](PrivateName const& private_name) -> String {
return private_name.description;
});
update_function_name(method_value, String::formatted("{}{}{}", prefix, prefix.is_empty() ? "" : " ", name));
};
if (property_key_or_private_name.has<PropertyKey>()) {
auto& property_key = property_key_or_private_name.get<PropertyKey>();
switch (kind()) {
case ClassMethod::Kind::Method:
set_function_name();
TRY(target.define_property_or_throw(property_key, { .value = method_value, .writable = true, .enumerable = false, .configurable = true }));
break;
case ClassMethod::Kind::Getter:
set_function_name("get");
TRY(target.define_property_or_throw(property_key, { .get = &method_function, .enumerable = true, .configurable = true }));
break;
case ClassMethod::Kind::Setter:
set_function_name("set");
TRY(target.define_property_or_throw(property_key, { .set = &method_function, .enumerable = true, .configurable = true }));
break;
default:
VERIFY_NOT_REACHED();
}
return ClassValue { normal_completion({}) };
} else {
auto& private_name = property_key_or_private_name.get<PrivateName>();
switch (kind()) {
case Kind::Method:
set_function_name();
return ClassValue { PrivateElement { private_name, PrivateElement::Kind::Method, method_value } };
case Kind::Getter:
set_function_name("get");
return ClassValue { PrivateElement { private_name, PrivateElement::Kind::Accessor, Accessor::create(interpreter.vm(), &method_function, nullptr) } };
case Kind::Setter:
set_function_name("set");
return ClassValue { PrivateElement { private_name, PrivateElement::Kind::Accessor, Accessor::create(interpreter.vm(), nullptr, &method_function) } };
default:
VERIFY_NOT_REACHED();
}
}
}
// We use this class to mimic Initializer : = AssignmentExpression of
// 10.2.1.3 Runtime Semantics: EvaluateBody, https://tc39.es/ecma262/#sec-runtime-semantics-evaluatebody
class ClassFieldInitializerStatement : public Statement {
public:
ClassFieldInitializerStatement(SourceRange source_range, NonnullRefPtr<Expression> expression, FlyString field_name)
: Statement(source_range)
, m_expression(move(expression))
, m_class_field_identifier_name(move(field_name))
{
}
Completion execute(Interpreter& interpreter, GlobalObject& global_object) const override
{
// 1. Assert: argumentsList is empty.
VERIFY(interpreter.vm().argument_count() == 0);
// 2. Assert: functionObject.[[ClassFieldInitializerName]] is not empty.
VERIFY(!m_class_field_identifier_name.is_empty());
// 3. If IsAnonymousFunctionDefinition(AssignmentExpression) is true, then
// a. Let value be NamedEvaluation of Initializer with argument functionObject.[[ClassFieldInitializerName]].
// 4. Else,
// a. Let rhs be the result of evaluating AssignmentExpression.
// b. Let value be ? GetValue(rhs).
auto value = TRY(interpreter.vm().named_evaluation_if_anonymous_function(global_object, m_expression, m_class_field_identifier_name));
// 5. Return Completion { [[Type]]: return, [[Value]]: value, [[Target]]: empty }.
return { Completion::Type::Return, value, {} };
}
void dump(int) const override
{
// This should not be dumped as it is never part of an actual AST.
VERIFY_NOT_REACHED();
}
private:
NonnullRefPtr<Expression> m_expression;
FlyString m_class_field_identifier_name; // [[ClassFieldIdentifierName]]
};
// 15.7.10 Runtime Semantics: ClassFieldDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-classfielddefinitionevaluation
ThrowCompletionOr<ClassElement::ClassValue> ClassField::class_element_evaluation(Interpreter& interpreter, GlobalObject& global_object, Object& target) const
{
auto property_key_or_private_name = TRY(class_key_to_property_name(interpreter, global_object, *m_key));
Handle<ECMAScriptFunctionObject> initializer {};
if (m_initializer) {
auto copy_initializer = m_initializer;
auto name = property_key_or_private_name.visit(
[&](PropertyKey const& property_key) -> String {
return property_key.is_number() ? property_key.to_string() : property_key.to_string_or_symbol().to_display_string();
},
[&](PrivateName const& private_name) -> String {
return private_name.description;
});
// FIXME: A potential optimization is not creating the functions here since these are never directly accessible.
auto function_code = create_ast_node<ClassFieldInitializerStatement>(m_initializer->source_range(), copy_initializer.release_nonnull(), name);
initializer = make_handle(ECMAScriptFunctionObject::create(interpreter.global_object(), String::empty(), String::empty(), *function_code, {}, 0, interpreter.lexical_environment(), interpreter.vm().running_execution_context().private_environment, FunctionKind::Normal, true, false, m_contains_direct_call_to_eval, false, property_key_or_private_name));
initializer->make_method(target);
}
return ClassValue {
ClassFieldDefinition {
move(property_key_or_private_name),
move(initializer),
}
};
}
static Optional<FlyString> nullopt_or_private_identifier_description(Expression const& expression)
{
if (is<PrivateIdentifier>(expression))
return static_cast<PrivateIdentifier const&>(expression).string();
return {};
}
Optional<FlyString> ClassField::private_bound_identifier() const
{
return nullopt_or_private_identifier_description(*m_key);
}
Optional<FlyString> ClassMethod::private_bound_identifier() const
{
return nullopt_or_private_identifier_description(*m_key);
}
// 15.7.11 Runtime Semantics: ClassStaticBlockDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-classstaticblockdefinitionevaluation
ThrowCompletionOr<ClassElement::ClassValue> StaticInitializer::class_element_evaluation(Interpreter& interpreter, GlobalObject& global_object, Object& home_object) const
{
// 1. Let lex be the running execution context's LexicalEnvironment.
auto* lexical_environment = interpreter.vm().running_execution_context().lexical_environment;
// 2. Let privateScope be the running execution context's PrivateEnvironment.
auto* private_scope = interpreter.vm().running_execution_context().private_environment;
// 3. Let sourceText be the empty sequence of Unicode code points.
// 4. Let formalParameters be an instance of the production FormalParameters : [empty] .
// 5. Let bodyFunction be OrdinaryFunctionCreate(%Function.prototype%, sourceText, formalParameters, ClassStaticBlockBody, non-lexical-this, lex, privateScope).
// Note: The function bodyFunction is never directly accessible to ECMAScript code.
auto* body_function = ECMAScriptFunctionObject::create(global_object, String::empty(), String::empty(), *m_function_body, {}, 0, lexical_environment, private_scope, FunctionKind::Normal, true, false, m_contains_direct_call_to_eval, false);
// 6. Perform MakeMethod(bodyFunction, homeObject).
body_function->make_method(home_object);
// 7. Return the ClassStaticBlockDefinition Record { [[BodyFunction]]: bodyFunction }.
return ClassValue { normal_completion(body_function) };
}
// 15.7.16 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-class-definitions-runtime-semantics-evaluation
// ClassExpression : class BindingIdentifier ClassTail
Completion ClassExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let className be StringValue of BindingIdentifier.
// 2. Let value be ? ClassDefinitionEvaluation of ClassTail with arguments className and className.
auto* value = TRY(class_definition_evaluation(interpreter, global_object, m_name, m_name.is_null() ? "" : m_name));
// 3. Set value.[[SourceText]] to the source text matched by ClassExpression.
value->set_source_text(m_source_text);
// 4. Return value.
return Value { value };
}
// 15.7.15 Runtime Semantics: BindingClassDeclarationEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-bindingclassdeclarationevaluation
static ThrowCompletionOr<Value> binding_class_declaration_evaluation(Interpreter& interpreter, GlobalObject& global_object, ClassExpression const& class_expression)
{
// ClassDeclaration : class ClassTail
if (!class_expression.has_name()) {
// 1. Let value be ? ClassDefinitionEvaluation of ClassTail with arguments undefined and "default".
auto value = TRY(class_expression.class_definition_evaluation(interpreter, global_object, {}, "default"));
// 2. Set value.[[SourceText]] to the source text matched by ClassDeclaration.
value->set_source_text(class_expression.source_text());
// 3. Return value.
return value;
}
// ClassDeclaration : class BindingIdentifier ClassTail
// 1. Let className be StringValue of BindingIdentifier.
auto class_name = class_expression.name();
VERIFY(!class_name.is_empty());
// 2. Let value be ? ClassDefinitionEvaluation of ClassTail with arguments className and className.
auto value = TRY(class_expression.class_definition_evaluation(interpreter, global_object, class_name, class_name));
// 3. Set value.[[SourceText]] to the source text matched by ClassDeclaration.
value->set_source_text(class_expression.source_text());
// 4. Let env be the running execution context's LexicalEnvironment.
auto* env = interpreter.lexical_environment();
// 5. Perform ? InitializeBoundName(className, value, env).
TRY(initialize_bound_name(global_object, class_name, value, env));
// 6. Return value.
return value;
}
// 15.7.16 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-class-definitions-runtime-semantics-evaluation
// ClassDeclaration : class BindingIdentifier ClassTail
Completion ClassDeclaration::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Perform ? BindingClassDeclarationEvaluation of this ClassDeclaration.
(void)TRY(binding_class_declaration_evaluation(interpreter, global_object, m_class_expression));
// 2. Return NormalCompletion(empty).
return normal_completion({});
}
// 15.7.14 Runtime Semantics: ClassDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-classdefinitionevaluation
ThrowCompletionOr<ECMAScriptFunctionObject*> ClassExpression::class_definition_evaluation(Interpreter& interpreter, GlobalObject& global_object, FlyString const& binding_name, FlyString const& class_name) const
{
auto& vm = interpreter.vm();
auto* environment = vm.lexical_environment();
VERIFY(environment);
auto* class_scope = new_declarative_environment(*environment);
// We might not set the lexical environment but we always want to restore it eventually.
ArmedScopeGuard restore_environment = [&] {
vm.running_execution_context().lexical_environment = environment;
};
if (!binding_name.is_null())
MUST(class_scope->create_immutable_binding(global_object, binding_name, true));
auto* outer_private_environment = vm.running_execution_context().private_environment;
auto* class_private_environment = new_private_environment(vm, outer_private_environment);
for (auto const& element : m_elements) {
auto opt_private_name = element.private_bound_identifier();
if (opt_private_name.has_value())
class_private_environment->add_private_name({}, opt_private_name.release_value());
}
auto* proto_parent = vm.current_realm()->global_object().object_prototype();
auto* constructor_parent = vm.current_realm()->global_object().function_prototype();
if (!m_super_class.is_null()) {
vm.running_execution_context().lexical_environment = class_scope;
// Note: Since our execute does evaluation and GetValue in once we must check for a valid reference first
Value super_class;
auto reference = TRY(m_super_class->to_reference(interpreter, global_object));
if (reference.is_valid_reference()) {
super_class = TRY(reference.get_value(global_object));
} else {
super_class = TRY(m_super_class->execute(interpreter, global_object)).release_value();
}
vm.running_execution_context().lexical_environment = environment;
if (super_class.is_null()) {
proto_parent = nullptr;
} else if (!super_class.is_constructor()) {
return vm.throw_completion<TypeError>(global_object, ErrorType::ClassExtendsValueNotAConstructorOrNull, super_class.to_string_without_side_effects());
} else {
auto super_class_prototype = TRY(super_class.get(global_object, vm.names.prototype));
if (!super_class_prototype.is_null() && !super_class_prototype.is_object())
return vm.throw_completion<TypeError>(global_object, ErrorType::ClassExtendsValueInvalidPrototype, super_class_prototype.to_string_without_side_effects());
if (super_class_prototype.is_null())
proto_parent = nullptr;
else
proto_parent = &super_class_prototype.as_object();
constructor_parent = &super_class.as_object();
}
}
auto* prototype = Object::create(global_object, proto_parent);
VERIFY(prototype);
vm.running_execution_context().lexical_environment = class_scope;
vm.running_execution_context().private_environment = class_private_environment;
ScopeGuard restore_private_environment = [&] {
vm.running_execution_context().private_environment = outer_private_environment;
};
// FIXME: Step 14.a is done in the parser. But maybe it shouldn't?
auto class_constructor_value = TRY(m_constructor->execute(interpreter, global_object)).release_value();
update_function_name(class_constructor_value, class_name);
VERIFY(class_constructor_value.is_function() && is<ECMAScriptFunctionObject>(class_constructor_value.as_function()));
auto* class_constructor = static_cast<ECMAScriptFunctionObject*>(&class_constructor_value.as_function());
class_constructor->set_home_object(prototype);
class_constructor->set_is_class_constructor();
class_constructor->define_direct_property(vm.names.prototype, prototype, Attribute::Writable);
TRY(class_constructor->internal_set_prototype_of(constructor_parent));
if (!m_super_class.is_null())
class_constructor->set_constructor_kind(ECMAScriptFunctionObject::ConstructorKind::Derived);
prototype->define_direct_property(vm.names.constructor, class_constructor, Attribute::Writable | Attribute::Configurable);
using StaticElement = Variant<ClassElement::ClassFieldDefinition, Handle<ECMAScriptFunctionObject>>;
Vector<PrivateElement> static_private_methods;
Vector<PrivateElement> instance_private_methods;
Vector<ClassElement::ClassFieldDefinition> instance_fields;
Vector<StaticElement> static_elements;
for (auto const& element : m_elements) {
// Note: All ClassElementEvaluation start with evaluating the name (or we fake it).
auto element_value = TRY(element.class_element_evaluation(interpreter, global_object, element.is_static() ? *class_constructor : *prototype));
if (element_value.has<PrivateElement>()) {
auto& container = element.is_static() ? static_private_methods : instance_private_methods;
auto& private_element = element_value.get<PrivateElement>();
auto added_to_existing = false;
// FIXME: We can skip this loop in most cases.
for (auto& existing : container) {
if (existing.key == private_element.key) {
VERIFY(existing.kind == PrivateElement::Kind::Accessor);
VERIFY(private_element.kind == PrivateElement::Kind::Accessor);
auto& accessor = private_element.value.as_accessor();
if (!accessor.getter())
existing.value.as_accessor().set_setter(accessor.setter());
else
existing.value.as_accessor().set_getter(accessor.getter());
added_to_existing = true;
}
}
if (!added_to_existing)
container.append(move(element_value.get<PrivateElement>()));
} else if (auto* class_field_definition_ptr = element_value.get_pointer<ClassElement::ClassFieldDefinition>()) {
if (element.is_static())
static_elements.append(move(*class_field_definition_ptr));
else
instance_fields.append(move(*class_field_definition_ptr));
} else if (element.class_element_kind() == ClassElement::ElementKind::StaticInitializer) {
// We use Completion to hold the ClassStaticBlockDefinition Record.
VERIFY(element_value.has<Completion>() && element_value.get<Completion>().value().has_value());
auto& element_object = element_value.get<Completion>().value()->as_object();
VERIFY(is<ECMAScriptFunctionObject>(element_object));
static_elements.append(make_handle(static_cast<ECMAScriptFunctionObject*>(&element_object)));
}
}
vm.running_execution_context().lexical_environment = environment;
restore_environment.disarm();
if (!binding_name.is_null())
MUST(class_scope->initialize_binding(global_object, binding_name, class_constructor));
for (auto& field : instance_fields)
class_constructor->add_field(field.name, field.initializer.is_null() ? nullptr : field.initializer.cell());
for (auto& private_method : instance_private_methods)
class_constructor->add_private_method(private_method);
for (auto& method : static_private_methods)
class_constructor->private_method_or_accessor_add(move(method));
for (auto& element : static_elements) {
TRY(element.visit(
[&](ClassElement::ClassFieldDefinition& field) -> ThrowCompletionOr<void> {
return TRY(class_constructor->define_field(field.name, field.initializer.is_null() ? nullptr : field.initializer.cell()));
},
[&](Handle<ECMAScriptFunctionObject> static_block_function) -> ThrowCompletionOr<void> {
VERIFY(!static_block_function.is_null());
// We discard any value returned here.
TRY(call(global_object, *static_block_function.cell(), class_constructor_value));
return {};
}));
}
return class_constructor;
}
void ASTNode::dump(int indent) const
{
print_indent(indent);
outln("{}", class_name());
}
void ScopeNode::dump(int indent) const
{
ASTNode::dump(indent);
if (!m_lexical_declarations.is_empty()) {
print_indent(indent + 1);
outln("(Lexical declarations)");
for (auto& declaration : m_lexical_declarations)
declaration.dump(indent + 2);
}
if (!m_var_declarations.is_empty()) {
print_indent(indent + 1);
outln("(Variable declarations)");
for (auto& declaration : m_var_declarations)
declaration.dump(indent + 2);
}
if (!m_functions_hoistable_with_annexB_extension.is_empty()) {
print_indent(indent + 1);
outln("(Hoisted functions via annexB extension)");
for (auto& declaration : m_functions_hoistable_with_annexB_extension)
declaration.dump(indent + 2);
}
if (!m_children.is_empty()) {
print_indent(indent + 1);
outln("(Children)");
for (auto& child : children())
child.dump(indent + 2);
}
}
void BinaryExpression::dump(int indent) const
{
char const* op_string = nullptr;
switch (m_op) {
case BinaryOp::Addition:
op_string = "+";
break;
case BinaryOp::Subtraction:
op_string = "-";
break;
case BinaryOp::Multiplication:
op_string = "*";
break;
case BinaryOp::Division:
op_string = "/";
break;
case BinaryOp::Modulo:
op_string = "%";
break;
case BinaryOp::Exponentiation:
op_string = "**";
break;
case BinaryOp::StrictlyEquals:
op_string = "===";
break;
case BinaryOp::StrictlyInequals:
op_string = "!==";
break;
case BinaryOp::LooselyEquals:
op_string = "==";
break;
case BinaryOp::LooselyInequals:
op_string = "!=";
break;
case BinaryOp::GreaterThan:
op_string = ">";
break;
case BinaryOp::GreaterThanEquals:
op_string = ">=";
break;
case BinaryOp::LessThan:
op_string = "<";
break;
case BinaryOp::LessThanEquals:
op_string = "<=";
break;
case BinaryOp::BitwiseAnd:
op_string = "&";
break;
case BinaryOp::BitwiseOr:
op_string = "|";
break;
case BinaryOp::BitwiseXor:
op_string = "^";
break;
case BinaryOp::LeftShift:
op_string = "<<";
break;
case BinaryOp::RightShift:
op_string = ">>";
break;
case BinaryOp::UnsignedRightShift:
op_string = ">>>";
break;
case BinaryOp::In:
op_string = "in";
break;
case BinaryOp::InstanceOf:
op_string = "instanceof";
break;
}
print_indent(indent);
outln("{}", class_name());
m_lhs->dump(indent + 1);
print_indent(indent + 1);
outln("{}", op_string);
m_rhs->dump(indent + 1);
}
void LogicalExpression::dump(int indent) const
{
char const* op_string = nullptr;
switch (m_op) {
case LogicalOp::And:
op_string = "&&";
break;
case LogicalOp::Or:
op_string = "||";
break;
case LogicalOp::NullishCoalescing:
op_string = "??";
break;
}
print_indent(indent);
outln("{}", class_name());
m_lhs->dump(indent + 1);
print_indent(indent + 1);
outln("{}", op_string);
m_rhs->dump(indent + 1);
}
void UnaryExpression::dump(int indent) const
{
char const* op_string = nullptr;
switch (m_op) {
case UnaryOp::BitwiseNot:
op_string = "~";
break;
case UnaryOp::Not:
op_string = "!";
break;
case UnaryOp::Plus:
op_string = "+";
break;
case UnaryOp::Minus:
op_string = "-";
break;
case UnaryOp::Typeof:
op_string = "typeof ";
break;
case UnaryOp::Void:
op_string = "void ";
break;
case UnaryOp::Delete:
op_string = "delete ";
break;
}
print_indent(indent);
outln("{}", class_name());
print_indent(indent + 1);
outln("{}", op_string);
m_lhs->dump(indent + 1);
}
void CallExpression::dump(int indent) const
{
print_indent(indent);
if (is<NewExpression>(*this))
outln("CallExpression [new]");
else
outln("CallExpression");
m_callee->dump(indent + 1);
for (auto& argument : m_arguments)
argument.value->dump(indent + 1);
}
void SuperCall::dump(int indent) const
{
print_indent(indent);
outln("SuperCall");
for (auto& argument : m_arguments)
argument.value->dump(indent + 1);
}
void ClassDeclaration::dump(int indent) const
{
ASTNode::dump(indent);
m_class_expression->dump(indent + 1);
}
ThrowCompletionOr<void> ClassDeclaration::for_each_bound_name(ThrowCompletionOrVoidCallback<FlyString const&>&& callback) const
{
if (m_class_expression->name().is_empty())
return {};
return callback(m_class_expression->name());
}
void ClassExpression::dump(int indent) const
{
print_indent(indent);
outln("ClassExpression: \"{}\"", m_name);
print_indent(indent);
outln("(Constructor)");
m_constructor->dump(indent + 1);
if (!m_super_class.is_null()) {
print_indent(indent);
outln("(Super Class)");
m_super_class->dump(indent + 1);
}
print_indent(indent);
outln("(Elements)");
for (auto& method : m_elements)
method.dump(indent + 1);
}
void ClassMethod::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("(Key)");
m_key->dump(indent + 1);
char const* kind_string = nullptr;
switch (m_kind) {
case Kind::Method:
kind_string = "Method";
break;
case Kind::Getter:
kind_string = "Getter";
break;
case Kind::Setter:
kind_string = "Setter";
break;
}
print_indent(indent);
outln("Kind: {}", kind_string);
print_indent(indent);
outln("Static: {}", is_static());
print_indent(indent);
outln("(Function)");
m_function->dump(indent + 1);
}
void ClassField::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("(Key)");
m_key->dump(indent + 1);
print_indent(indent);
outln("Static: {}", is_static());
if (m_initializer) {
print_indent(indent);
outln("(Initializer)");
m_initializer->dump(indent + 1);
}
}
void StaticInitializer::dump(int indent) const
{
ASTNode::dump(indent);
m_function_body->dump(indent + 1);
}
void StringLiteral::dump(int indent) const
{
print_indent(indent);
outln("StringLiteral \"{}\"", m_value);
}
void SuperExpression::dump(int indent) const
{
print_indent(indent);
outln("super");
}
void NumericLiteral::dump(int indent) const
{
print_indent(indent);
outln("NumericLiteral {}", m_value);
}
void BigIntLiteral::dump(int indent) const
{
print_indent(indent);
outln("BigIntLiteral {}", m_value);
}
void BooleanLiteral::dump(int indent) const
{
print_indent(indent);
outln("BooleanLiteral {}", m_value);
}
void NullLiteral::dump(int indent) const
{
print_indent(indent);
outln("null");
}
bool BindingPattern::contains_expression() const
{
for (auto& entry : entries) {
if (entry.initializer)
return true;
if (auto binding_ptr = entry.alias.get_pointer<NonnullRefPtr<BindingPattern>>(); binding_ptr && (*binding_ptr)->contains_expression())
return true;
}
return false;
}
ThrowCompletionOr<void> BindingPattern::for_each_bound_name(ThrowCompletionOrVoidCallback<FlyString const&>&& callback) const
{
for (auto const& entry : entries) {
auto const& alias = entry.alias;
if (alias.has<NonnullRefPtr<Identifier>>()) {
TRY(callback(alias.get<NonnullRefPtr<Identifier>>()->string()));
} else if (alias.has<NonnullRefPtr<BindingPattern>>()) {
TRY(alias.get<NonnullRefPtr<BindingPattern>>()->for_each_bound_name(forward<decltype(callback)>(callback)));
} else {
auto const& name = entry.name;
if (name.has<NonnullRefPtr<Identifier>>())
TRY(callback(name.get<NonnullRefPtr<Identifier>>()->string()));
}
}
return {};
}
void BindingPattern::dump(int indent) const
{
print_indent(indent);
outln("BindingPattern {}", kind == Kind::Array ? "Array" : "Object");
for (auto& entry : entries) {
print_indent(indent + 1);
outln("(Property)");
if (kind == Kind::Object) {
print_indent(indent + 2);
outln("(Identifier)");
if (entry.name.has<NonnullRefPtr<Identifier>>()) {
entry.name.get<NonnullRefPtr<Identifier>>()->dump(indent + 3);
} else {
entry.name.get<NonnullRefPtr<Expression>>()->dump(indent + 3);
}
} else if (entry.is_elision()) {
print_indent(indent + 2);
outln("(Elision)");
continue;
}
print_indent(indent + 2);
outln("(Pattern{})", entry.is_rest ? " rest=true" : "");
if (entry.alias.has<NonnullRefPtr<Identifier>>()) {
entry.alias.get<NonnullRefPtr<Identifier>>()->dump(indent + 3);
} else if (entry.alias.has<NonnullRefPtr<BindingPattern>>()) {
entry.alias.get<NonnullRefPtr<BindingPattern>>()->dump(indent + 3);
} else if (entry.alias.has<NonnullRefPtr<MemberExpression>>()) {
entry.alias.get<NonnullRefPtr<MemberExpression>>()->dump(indent + 3);
} else {
print_indent(indent + 3);
outln("<empty>");
}
if (entry.initializer) {
print_indent(indent + 2);
outln("(Initializer)");
entry.initializer->dump(indent + 3);
}
}
}
void FunctionNode::dump(int indent, String const& class_name) const
{
print_indent(indent);
auto is_async = m_kind == FunctionKind::Async || m_kind == FunctionKind::AsyncGenerator;
auto is_generator = m_kind == FunctionKind::Generator || m_kind == FunctionKind::AsyncGenerator;
outln("{}{}{} '{}'", class_name, is_async ? " async" : "", is_generator ? "*" : "", name());
if (m_contains_direct_call_to_eval) {
print_indent(indent + 1);
outln("\033[31;1m(direct eval)\033[0m");
}
if (!m_parameters.is_empty()) {
print_indent(indent + 1);
outln("(Parameters)");
for (auto& parameter : m_parameters) {
print_indent(indent + 2);
if (parameter.is_rest)
out("...");
parameter.binding.visit(
[&](FlyString const& name) {
outln("{}", name);
},
[&](BindingPattern const& pattern) {
pattern.dump(indent + 2);
});
if (parameter.default_value)
parameter.default_value->dump(indent + 3);
}
}
print_indent(indent + 1);
outln("(Body)");
body().dump(indent + 2);
}
void FunctionDeclaration::dump(int indent) const
{
FunctionNode::dump(indent, class_name());
}
ThrowCompletionOr<void> FunctionDeclaration::for_each_bound_name(ThrowCompletionOrVoidCallback<FlyString const&>&& callback) const
{
if (name().is_empty())
return {};
return callback(name());
}
void FunctionExpression::dump(int indent) const
{
FunctionNode::dump(indent, class_name());
}
void YieldExpression::dump(int indent) const
{
ASTNode::dump(indent);
if (argument())
argument()->dump(indent + 1);
}
void AwaitExpression::dump(int indent) const
{
ASTNode::dump(indent);
m_argument->dump(indent + 1);
}
void ReturnStatement::dump(int indent) const
{
ASTNode::dump(indent);
if (argument())
argument()->dump(indent + 1);
}
void IfStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("If");
predicate().dump(indent + 1);
consequent().dump(indent + 1);
if (alternate()) {
print_indent(indent);
outln("Else");
alternate()->dump(indent + 1);
}
}
void WhileStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("While");
test().dump(indent + 1);
body().dump(indent + 1);
}
void WithStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent + 1);
outln("Object");
object().dump(indent + 2);
print_indent(indent + 1);
outln("Body");
body().dump(indent + 2);
}
void DoWhileStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("DoWhile");
test().dump(indent + 1);
body().dump(indent + 1);
}
void ForStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("For");
if (init())
init()->dump(indent + 1);
if (test())
test()->dump(indent + 1);
if (update())
update()->dump(indent + 1);
body().dump(indent + 1);
}
void ForInStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("ForIn");
lhs().visit([&](auto& lhs) { lhs->dump(indent + 1); });
rhs().dump(indent + 1);
body().dump(indent + 1);
}
void ForOfStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("ForOf");
lhs().visit([&](auto& lhs) { lhs->dump(indent + 1); });
rhs().dump(indent + 1);
body().dump(indent + 1);
}
void ForAwaitOfStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("ForAwaitOf");
m_lhs.visit([&](auto& lhs) { lhs->dump(indent + 1); });
m_rhs->dump(indent + 1);
m_body->dump(indent + 1);
}
// 13.1.3 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-identifiers-runtime-semantics-evaluation
Completion Identifier::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return ? ResolveBinding(StringValue of Identifier).
auto reference = TRY(interpreter.vm().resolve_binding(m_string));
// NOTE: The spec wants us to return the reference directly; this is not possible with ASTNode::execute() (short of letting it return a variant).
// So, instead of calling GetValue at the call site, we do it here.
return TRY(reference.get_value(global_object));
}
void Identifier::dump(int indent) const
{
print_indent(indent);
outln("Identifier \"{}\"", m_string);
}
Completion PrivateIdentifier::execute(Interpreter&, GlobalObject&) const
{
// Note: This should be handled by either the member expression this is part of
// or the binary expression in the case of `#foo in bar`.
VERIFY_NOT_REACHED();
}
void PrivateIdentifier::dump(int indent) const
{
print_indent(indent);
outln("PrivateIdentifier \"{}\"", m_string);
}
void SpreadExpression::dump(int indent) const
{
ASTNode::dump(indent);
m_target->dump(indent + 1);
}
Completion SpreadExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
return m_target->execute(interpreter, global_object);
}
// 13.2.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-this-keyword-runtime-semantics-evaluation
Completion ThisExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return ? ResolveThisBinding().
return interpreter.vm().resolve_this_binding(global_object);
}
void ThisExpression::dump(int indent) const
{
ASTNode::dump(indent);
}
// 13.15.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-assignment-operators-runtime-semantics-evaluation
Completion AssignmentExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
if (m_op == AssignmentOp::Assignment) {
// AssignmentExpression : LeftHandSideExpression = AssignmentExpression
return m_lhs.visit(
// 1. If LeftHandSideExpression is neither an ObjectLiteral nor an ArrayLiteral, then
[&](NonnullRefPtr<Expression> const& lhs) -> ThrowCompletionOr<Value> {
// a. Let lref be the result of evaluating LeftHandSideExpression.
// b. ReturnIfAbrupt(lref).
auto reference = TRY(lhs->to_reference(interpreter, global_object));
Value rhs_result;
// c. If IsAnonymousFunctionDefinition(AssignmentExpression) and IsIdentifierRef of LeftHandSideExpression are both true, then
if (lhs->is_identifier()) {
// i. Let rval be NamedEvaluation of AssignmentExpression with argument lref.[[ReferencedName]].
auto& identifier_name = static_cast<Identifier const&>(*lhs).string();
rhs_result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(global_object, m_rhs, identifier_name));
}
// d. Else,
else {
// i. Let rref be the result of evaluating AssignmentExpression.
// ii. Let rval be ? GetValue(rref).
rhs_result = TRY(m_rhs->execute(interpreter, global_object)).release_value();
}
// e. Perform ? PutValue(lref, rval).
TRY(reference.put_value(global_object, rhs_result));
// f. Return rval.
return rhs_result;
},
// 2. Let assignmentPattern be the AssignmentPattern that is covered by LeftHandSideExpression.
[&](NonnullRefPtr<BindingPattern> const& pattern) -> ThrowCompletionOr<Value> {
// 3. Let rref be the result of evaluating AssignmentExpression.
// 4. Let rval be ? GetValue(rref).
auto rhs_result = TRY(m_rhs->execute(interpreter, global_object)).release_value();
// 5. Perform ? DestructuringAssignmentEvaluation of assignmentPattern using rval as the argument.
TRY(interpreter.vm().destructuring_assignment_evaluation(pattern, rhs_result, global_object));
// 6. Return rval.
return rhs_result;
});
}
VERIFY(m_lhs.has<NonnullRefPtr<Expression>>());
// 1. Let lref be the result of evaluating LeftHandSideExpression.
auto& lhs_expression = *m_lhs.get<NonnullRefPtr<Expression>>();
auto reference = TRY(lhs_expression.to_reference(interpreter, global_object));
// 2. Let lval be ? GetValue(lref).
auto lhs_result = TRY(reference.get_value(global_object));
// AssignmentExpression : LeftHandSideExpression {&&=, ||=, ??=} AssignmentExpression
if (m_op == AssignmentOp::AndAssignment || m_op == AssignmentOp::OrAssignment || m_op == AssignmentOp::NullishAssignment) {
switch (m_op) {
// AssignmentExpression : LeftHandSideExpression &&= AssignmentExpression
case AssignmentOp::AndAssignment:
// 3. Let lbool be ! ToBoolean(lval).
// 4. If lbool is false, return lval.
if (!lhs_result.to_boolean())
return lhs_result;
break;
// AssignmentExpression : LeftHandSideExpression ||= AssignmentExpression
case AssignmentOp::OrAssignment:
// 3. Let lbool be ! ToBoolean(lval).
// 4. If lbool is true, return lval.
if (lhs_result.to_boolean())
return lhs_result;
break;
// AssignmentExpression : LeftHandSideExpression ??= AssignmentExpression
case AssignmentOp::NullishAssignment:
// 3. If lval is neither undefined nor null, return lval.
if (!lhs_result.is_nullish())
return lhs_result;
break;
default:
VERIFY_NOT_REACHED();
}
Value rhs_result;
// 5. If IsAnonymousFunctionDefinition(AssignmentExpression) is true and IsIdentifierRef of LeftHandSideExpression is true, then
if (lhs_expression.is_identifier()) {
// a. Let rval be NamedEvaluation of AssignmentExpression with argument lref.[[ReferencedName]].
auto& identifier_name = static_cast<Identifier const&>(lhs_expression).string();
rhs_result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(global_object, m_rhs, identifier_name));
}
// 6. Else,
else {
// a. Let rref be the result of evaluating AssignmentExpression.
// b. Let rval be ? GetValue(rref).
rhs_result = TRY(m_rhs->execute(interpreter, global_object)).release_value();
}
// 7. Perform ? PutValue(lref, rval).
TRY(reference.put_value(global_object, rhs_result));
// 8. Return rval.
return rhs_result;
}
// AssignmentExpression : LeftHandSideExpression AssignmentOperator AssignmentExpression
// 3. Let rref be the result of evaluating AssignmentExpression.
// 4. Let rval be ? GetValue(rref).
auto rhs_result = TRY(m_rhs->execute(interpreter, global_object)).release_value();
// 5. Let assignmentOpText be the source text matched by AssignmentOperator.
// 6. Let opText be the sequence of Unicode code points associated with assignmentOpText in the following table:
// 7. Let r be ApplyStringOrNumericBinaryOperator(lval, opText, rval).
switch (m_op) {
case AssignmentOp::AdditionAssignment:
rhs_result = TRY(add(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::SubtractionAssignment:
rhs_result = TRY(sub(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::MultiplicationAssignment:
rhs_result = TRY(mul(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::DivisionAssignment:
rhs_result = TRY(div(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::ModuloAssignment:
rhs_result = TRY(mod(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::ExponentiationAssignment:
rhs_result = TRY(exp(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::BitwiseAndAssignment:
rhs_result = TRY(bitwise_and(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::BitwiseOrAssignment:
rhs_result = TRY(bitwise_or(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::BitwiseXorAssignment:
rhs_result = TRY(bitwise_xor(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::LeftShiftAssignment:
rhs_result = TRY(left_shift(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::RightShiftAssignment:
rhs_result = TRY(right_shift(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::UnsignedRightShiftAssignment:
rhs_result = TRY(unsigned_right_shift(global_object, lhs_result, rhs_result));
break;
case AssignmentOp::Assignment:
case AssignmentOp::AndAssignment:
case AssignmentOp::OrAssignment:
case AssignmentOp::NullishAssignment:
VERIFY_NOT_REACHED();
}
// 8. Perform ? PutValue(lref, r).
TRY(reference.put_value(global_object, rhs_result));
// 9. Return r.
return rhs_result;
}
// 13.4.2.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-postfix-increment-operator-runtime-semantics-evaluation
// 13.4.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-postfix-decrement-operator-runtime-semantics-evaluation
// 13.4.4.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-prefix-increment-operator-runtime-semantics-evaluation
// 13.4.5.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-prefix-decrement-operator-runtime-semantics-evaluation
Completion UpdateExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let expr be the result of evaluating <Expression>.
auto reference = TRY(m_argument->to_reference(interpreter, global_object));
// 2. Let oldValue be ? ToNumeric(? GetValue(expr)).
auto old_value = TRY(reference.get_value(global_object));
old_value = TRY(old_value.to_numeric(global_object));
Value new_value;
switch (m_op) {
case UpdateOp::Increment:
// 3. If Type(oldValue) is Number, then
if (old_value.is_number()) {
// a. Let newValue be ! Number::add(oldValue, 1𝔽).
new_value = Value(old_value.as_double() + 1);
}
// 4. Else,
else {
// a. Assert: Type(oldValue) is BigInt.
// b. Let newValue be ! BigInt::add(oldValue, 1ℤ).
new_value = js_bigint(interpreter.heap(), old_value.as_bigint().big_integer().plus(Crypto::SignedBigInteger { 1 }));
}
break;
case UpdateOp::Decrement:
// 3. If Type(oldValue) is Number, then
if (old_value.is_number()) {
// a. Let newValue be ! Number::subtract(oldValue, 1𝔽).
new_value = Value(old_value.as_double() - 1);
}
// 4. Else,
else {
// a. Assert: Type(oldValue) is BigInt.
// b. Let newValue be ! BigInt::subtract(oldValue, 1ℤ).
new_value = js_bigint(interpreter.heap(), old_value.as_bigint().big_integer().minus(Crypto::SignedBigInteger { 1 }));
}
break;
default:
VERIFY_NOT_REACHED();
}
// 5. Perform ? PutValue(expr, newValue).
TRY(reference.put_value(global_object, new_value));
// 6. Return newValue.
// 6. Return oldValue.
return m_prefixed ? new_value : old_value;
}
void AssignmentExpression::dump(int indent) const
{
char const* op_string = nullptr;
switch (m_op) {
case AssignmentOp::Assignment:
op_string = "=";
break;
case AssignmentOp::AdditionAssignment:
op_string = "+=";
break;
case AssignmentOp::SubtractionAssignment:
op_string = "-=";
break;
case AssignmentOp::MultiplicationAssignment:
op_string = "*=";
break;
case AssignmentOp::DivisionAssignment:
op_string = "/=";
break;
case AssignmentOp::ModuloAssignment:
op_string = "%=";
break;
case AssignmentOp::ExponentiationAssignment:
op_string = "**=";
break;
case AssignmentOp::BitwiseAndAssignment:
op_string = "&=";
break;
case AssignmentOp::BitwiseOrAssignment:
op_string = "|=";
break;
case AssignmentOp::BitwiseXorAssignment:
op_string = "^=";
break;
case AssignmentOp::LeftShiftAssignment:
op_string = "<<=";
break;
case AssignmentOp::RightShiftAssignment:
op_string = ">>=";
break;
case AssignmentOp::UnsignedRightShiftAssignment:
op_string = ">>>=";
break;
case AssignmentOp::AndAssignment:
op_string = "&&=";
break;
case AssignmentOp::OrAssignment:
op_string = "||=";
break;
case AssignmentOp::NullishAssignment:
op_string = "\?\?=";
break;
}
ASTNode::dump(indent);
print_indent(indent + 1);
outln("{}", op_string);
m_lhs.visit([&](auto& lhs) { lhs->dump(indent + 1); });
m_rhs->dump(indent + 1);
}
void UpdateExpression::dump(int indent) const
{
char const* op_string = nullptr;
switch (m_op) {
case UpdateOp::Increment:
op_string = "++";
break;
case UpdateOp::Decrement:
op_string = "--";
break;
}
ASTNode::dump(indent);
if (m_prefixed) {
print_indent(indent + 1);
outln("{}", op_string);
}
m_argument->dump(indent + 1);
if (!m_prefixed) {
print_indent(indent + 1);
outln("{}", op_string);
}
}
// 14.3.1.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-let-and-const-declarations-runtime-semantics-evaluation
// 14.3.2.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-variable-statement-runtime-semantics-evaluation
Completion VariableDeclaration::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
for (auto& declarator : m_declarations) {
if (auto* init = declarator.init()) {
TRY(declarator.target().visit(
[&](NonnullRefPtr<Identifier> const& id) -> ThrowCompletionOr<void> {
auto reference = TRY(id->to_reference(interpreter, global_object));
auto initializer_result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(global_object, *init, id->string()));
VERIFY(!initializer_result.is_empty());
if (m_declaration_kind == DeclarationKind::Var)
return reference.put_value(global_object, initializer_result);
else
return reference.initialize_referenced_binding(global_object, initializer_result);
},
[&](NonnullRefPtr<BindingPattern> const& pattern) -> ThrowCompletionOr<void> {
auto initializer_result = TRY(init->execute(interpreter, global_object)).release_value();
Environment* environment = m_declaration_kind == DeclarationKind::Var ? nullptr : interpreter.lexical_environment();
return interpreter.vm().binding_initialization(pattern, initializer_result, environment, global_object);
}));
} else if (m_declaration_kind != DeclarationKind::Var) {
VERIFY(declarator.target().has<NonnullRefPtr<Identifier>>());
auto& identifier = declarator.target().get<NonnullRefPtr<Identifier>>();
auto reference = TRY(identifier->to_reference(interpreter, global_object));
TRY(reference.initialize_referenced_binding(global_object, js_undefined()));
}
}
return normal_completion({});
}
Completion VariableDeclarator::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// NOTE: VariableDeclarator execution is handled by VariableDeclaration.
VERIFY_NOT_REACHED();
}
ThrowCompletionOr<void> VariableDeclaration::for_each_bound_name(ThrowCompletionOrVoidCallback<FlyString const&>&& callback) const
{
for (auto const& entry : declarations()) {
TRY(entry.target().visit(
[&](NonnullRefPtr<Identifier> const& id) {
return callback(id->string());
},
[&](NonnullRefPtr<BindingPattern> const& binding) {
return binding->for_each_bound_name([&](auto const& name) {
return callback(name);
});
}));
}
return {};
}
void VariableDeclaration::dump(int indent) const
{
char const* declaration_kind_string = nullptr;
switch (m_declaration_kind) {
case DeclarationKind::Let:
declaration_kind_string = "Let";
break;
case DeclarationKind::Var:
declaration_kind_string = "Var";
break;
case DeclarationKind::Const:
declaration_kind_string = "Const";
break;
}
ASTNode::dump(indent);
print_indent(indent + 1);
outln("{}", declaration_kind_string);
for (auto& declarator : m_declarations)
declarator.dump(indent + 1);
}
void VariableDeclarator::dump(int indent) const
{
ASTNode::dump(indent);
m_target.visit([indent](auto const& value) { value->dump(indent + 1); });
if (m_init)
m_init->dump(indent + 1);
}
void ObjectProperty::dump(int indent) const
{
ASTNode::dump(indent);
if (m_property_type == Type::Spread) {
print_indent(indent + 1);
outln("...Spreading");
m_key->dump(indent + 1);
} else {
m_key->dump(indent + 1);
m_value->dump(indent + 1);
}
}
void ObjectExpression::dump(int indent) const
{
ASTNode::dump(indent);
for (auto& property : m_properties) {
property.dump(indent + 1);
}
}
void ExpressionStatement::dump(int indent) const
{
ASTNode::dump(indent);
m_expression->dump(indent + 1);
}
Completion ObjectProperty::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// NOTE: ObjectProperty execution is handled by ObjectExpression.
VERIFY_NOT_REACHED();
}
// 13.2.5.4 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-object-initializer-runtime-semantics-evaluation
Completion ObjectExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let obj be ! OrdinaryObjectCreate(%Object.prototype%).
auto* object = Object::create(global_object, global_object.object_prototype());
// 2. Perform ? PropertyDefinitionEvaluation of PropertyDefinitionList with argument obj.
for (auto& property : m_properties) {
auto key = TRY(property.key().execute(interpreter, global_object)).release_value();
// PropertyDefinition : ... AssignmentExpression
if (property.type() == ObjectProperty::Type::Spread) {
// 4. Return ? CopyDataProperties(object, fromValue, excludedNames).
TRY(object->copy_data_properties(key, {}, global_object));
continue;
}
auto value = TRY(property.value().execute(interpreter, global_object)).release_value();
// 8. If isProtoSetter is true, then
if (property.type() == ObjectProperty::Type::ProtoSetter) {
// a. If Type(propValue) is either Object or Null, then
if (value.is_object() || value.is_null()) {
// i. Perform ! object.[[SetPrototypeOf]](propValue).
MUST(object->internal_set_prototype_of(value.is_object() ? &value.as_object() : nullptr));
}
// b. Return unused.
continue;
}
if (value.is_function() && property.is_method())
static_cast<ECMAScriptFunctionObject&>(value.as_function()).set_home_object(object);
auto property_key = TRY(PropertyKey::from_value(global_object, key));
auto name = TRY(get_function_property_name(property_key));
if (property.type() == ObjectProperty::Type::Getter) {
name = String::formatted("get {}", name);
} else if (property.type() == ObjectProperty::Type::Setter) {
name = String::formatted("set {}", name);
}
update_function_name(value, name);
switch (property.type()) {
case ObjectProperty::Type::Getter:
VERIFY(value.is_function());
object->define_direct_accessor(property_key, &value.as_function(), nullptr, Attribute::Configurable | Attribute::Enumerable);
break;
case ObjectProperty::Type::Setter:
VERIFY(value.is_function());
object->define_direct_accessor(property_key, nullptr, &value.as_function(), Attribute::Configurable | Attribute::Enumerable);
break;
case ObjectProperty::Type::KeyValue:
object->define_direct_property(property_key, value, default_attributes);
break;
case ObjectProperty::Type::Spread:
default:
VERIFY_NOT_REACHED();
}
}
// 3. Return obj.
return Value { object };
}
void MemberExpression::dump(int indent) const
{
print_indent(indent);
outln("{}(computed={})", class_name(), is_computed());
m_object->dump(indent + 1);
m_property->dump(indent + 1);
}
String MemberExpression::to_string_approximation() const
{
String object_string = "<object>";
if (is<Identifier>(*m_object))
object_string = static_cast<Identifier const&>(*m_object).string();
if (is_computed())
return String::formatted("{}[<computed>]", object_string);
return String::formatted("{}.{}", object_string, verify_cast<Identifier>(*m_property).string());
}
// 13.3.2.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-property-accessors-runtime-semantics-evaluation
Completion MemberExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto reference = TRY(to_reference(interpreter, global_object));
return TRY(reference.get_value(global_object));
}
bool MemberExpression::ends_in_private_name() const
{
if (is_computed())
return false;
if (is<PrivateIdentifier>(*m_property))
return true;
if (is<MemberExpression>(*m_property))
return static_cast<MemberExpression const&>(*m_property).ends_in_private_name();
return false;
}
void OptionalChain::dump(int indent) const
{
print_indent(indent);
outln("{}", class_name());
m_base->dump(indent + 1);
for (auto& reference : m_references) {
reference.visit(
[&](Call const& call) {
print_indent(indent + 1);
outln("Call({})", call.mode == Mode::Optional ? "Optional" : "Not Optional");
for (auto& argument : call.arguments)
argument.value->dump(indent + 2);
},
[&](ComputedReference const& ref) {
print_indent(indent + 1);
outln("ComputedReference({})", ref.mode == Mode::Optional ? "Optional" : "Not Optional");
ref.expression->dump(indent + 2);
},
[&](MemberReference const& ref) {
print_indent(indent + 1);
outln("MemberReference({})", ref.mode == Mode::Optional ? "Optional" : "Not Optional");
ref.identifier->dump(indent + 2);
},
[&](PrivateMemberReference const& ref) {
print_indent(indent + 1);
outln("PrivateMemberReference({})", ref.mode == Mode::Optional ? "Optional" : "Not Optional");
ref.private_identifier->dump(indent + 2);
});
}
}
ThrowCompletionOr<OptionalChain::ReferenceAndValue> OptionalChain::to_reference_and_value(Interpreter& interpreter, GlobalObject& global_object) const
{
auto base_reference = TRY(m_base->to_reference(interpreter, global_object));
auto base = base_reference.is_unresolvable()
? TRY(m_base->execute(interpreter, global_object)).release_value()
: TRY(base_reference.get_value(global_object));
for (auto& reference : m_references) {
auto is_optional = reference.visit([](auto& ref) { return ref.mode; }) == Mode::Optional;
if (is_optional && base.is_nullish())
return ReferenceAndValue { {}, js_undefined() };
auto expression = reference.visit(
[&](Call const& call) -> NonnullRefPtr<Expression> {
return create_ast_node<CallExpression>(source_range(),
create_ast_node<SyntheticReferenceExpression>(source_range(), base_reference, base),
call.arguments);
},
[&](ComputedReference const& ref) -> NonnullRefPtr<Expression> {
return create_ast_node<MemberExpression>(source_range(),
create_ast_node<SyntheticReferenceExpression>(source_range(), base_reference, base),
ref.expression,
true);
},
[&](MemberReference const& ref) -> NonnullRefPtr<Expression> {
return create_ast_node<MemberExpression>(source_range(),
create_ast_node<SyntheticReferenceExpression>(source_range(), base_reference, base),
ref.identifier,
false);
},
[&](PrivateMemberReference const& ref) -> NonnullRefPtr<Expression> {
return create_ast_node<MemberExpression>(source_range(),
create_ast_node<SyntheticReferenceExpression>(source_range(), base_reference, base),
ref.private_identifier,
false);
});
if (is<CallExpression>(*expression)) {
base_reference = JS::Reference {};
base = TRY(expression->execute(interpreter, global_object)).release_value();
} else {
base_reference = TRY(expression->to_reference(interpreter, global_object));
base = TRY(base_reference.get_value(global_object));
}
}
return ReferenceAndValue { move(base_reference), base };
}
// 13.3.9.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-optional-chaining-evaluation
Completion OptionalChain::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
return TRY(to_reference_and_value(interpreter, global_object)).value;
}
ThrowCompletionOr<JS::Reference> OptionalChain::to_reference(Interpreter& interpreter, GlobalObject& global_object) const
{
return TRY(to_reference_and_value(interpreter, global_object)).reference;
}
void MetaProperty::dump(int indent) const
{
String name;
if (m_type == MetaProperty::Type::NewTarget)
name = "new.target";
else if (m_type == MetaProperty::Type::ImportMeta)
name = "import.meta";
else
VERIFY_NOT_REACHED();
print_indent(indent);
outln("{} {}", class_name(), name);
}
// 13.3.12.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-meta-properties-runtime-semantics-evaluation
Completion MetaProperty::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// NewTarget : new . target
if (m_type == MetaProperty::Type::NewTarget) {
// 1. Return GetNewTarget().
return interpreter.vm().get_new_target();
}
// ImportMeta : import . meta
if (m_type == MetaProperty::Type::ImportMeta) {
// 1. Let module be ! GetActiveScriptOrModule().
auto script_or_module = interpreter.vm().get_active_script_or_module();
// 2. Assert: module is a Source Text Module Record.
VERIFY(script_or_module.has<WeakPtr<Module>>());
VERIFY(script_or_module.get<WeakPtr<Module>>());
VERIFY(is<SourceTextModule>(*script_or_module.get<WeakPtr<Module>>()));
auto& module = static_cast<SourceTextModule&>(*script_or_module.get<WeakPtr<Module>>());
// 3. Let importMeta be module.[[ImportMeta]].
auto* import_meta = module.import_meta();
// 4. If importMeta is empty, then
if (import_meta == nullptr) {
// a. Set importMeta to ! OrdinaryObjectCreate(null).
import_meta = Object::create(global_object, nullptr);
// b. Let importMetaValues be ! HostGetImportMetaProperties(module).
auto import_meta_values = interpreter.vm().host_get_import_meta_properties(module);
// c. For each Record { [[Key]], [[Value]] } p of importMetaValues, do
for (auto& entry : import_meta_values) {
// i. Perform ! CreateDataPropertyOrThrow(importMeta, p.[[Key]], p.[[Value]]).
MUST(import_meta->create_data_property_or_throw(entry.key, entry.value));
}
// d. Perform ! HostFinalizeImportMeta(importMeta, module).
interpreter.vm().host_finalize_import_meta(import_meta, module);
// e. Set module.[[ImportMeta]] to importMeta.
module.set_import_meta({}, import_meta);
// f. Return importMeta.
return Value { import_meta };
}
// 5. Else,
else {
// a. Assert: Type(importMeta) is Object.
// Note: This is always true by the type.
// b. Return importMeta.
return Value { import_meta };
}
}
VERIFY_NOT_REACHED();
}
void ImportCall::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("(Specifier)");
m_specifier->dump(indent + 1);
if (m_options) {
outln("(Options)");
m_options->dump(indent + 1);
}
}
// 13.3.10.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-import-call-runtime-semantics-evaluation
// Also includes assertions from proposal: https://tc39.es/proposal-import-assertions/#sec-import-call-runtime-semantics-evaluation
Completion ImportCall::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 2.1.1.1 EvaluateImportCall ( specifierExpression [ , optionsExpression ] ), https://tc39.es/proposal-import-assertions/#sec-evaluate-import-call
// 1. Let referencingScriptOrModule be ! GetActiveScriptOrModule().
auto referencing_script_or_module = interpreter.vm().get_active_script_or_module();
// 2. Let specifierRef be the result of evaluating specifierExpression.
// 3. Let specifier be ? GetValue(specifierRef).
auto specifier = TRY(m_specifier->execute(interpreter, global_object));
auto options_value = js_undefined();
// 4. If optionsExpression is present, then
if (m_options) {
// a. Let optionsRef be the result of evaluating optionsExpression.
// b. Let options be ? GetValue(optionsRef).
options_value = TRY(m_options->execute(interpreter, global_object)).release_value();
}
// 5. Else,
// a. Let options be undefined.
// Note: options_value is undefined by default.
// 6. Let promiseCapability be ! NewPromiseCapability(%Promise%).
auto promise_capability = MUST(new_promise_capability(global_object, global_object.promise_constructor()));
// 7. Let specifierString be ToString(specifier).
// 8. IfAbruptRejectPromise(specifierString, promiseCapability).
auto specifier_string = TRY_OR_REJECT_WITH_VALUE(global_object, promise_capability, specifier->to_string(global_object));
// 9. Let assertions be a new empty List.
Vector<ModuleRequest::Assertion> assertions;
// 10. If options is not undefined, then
if (!options_value.is_undefined()) {
// a. If Type(options) is not Object,
if (!options_value.is_object()) {
auto* error = TypeError::create(global_object, String::formatted(ErrorType::NotAnObject.message(), "ImportOptions"));
// i. Perform ! Call(promiseCapability.[[Reject]], undefined, « a newly created TypeError object »).
MUST(call(global_object, *promise_capability.reject, js_undefined(), error));
// ii. Return promiseCapability.[[Promise]].
return Value { promise_capability.promise };
}
// b. Let assertionsObj be Get(options, "assert").
// c. IfAbruptRejectPromise(assertionsObj, promiseCapability).
auto assertion_object = TRY_OR_REJECT_WITH_VALUE(global_object, promise_capability, options_value.get(global_object, interpreter.vm().names.assert));
// d. If assertionsObj is not undefined,
if (!assertion_object.is_undefined()) {
// i. If Type(assertionsObj) is not Object,
if (!assertion_object.is_object()) {
auto* error = TypeError::create(global_object, String::formatted(ErrorType::NotAnObject.message(), "ImportOptionsAssertions"));
// 1. Perform ! Call(promiseCapability.[[Reject]], undefined, « a newly created TypeError object »).
MUST(call(global_object, *promise_capability.reject, js_undefined(), error));
// 2. Return promiseCapability.[[Promise]].
return Value { promise_capability.promise };
}
// ii. Let keys be EnumerableOwnPropertyNames(assertionsObj, key).
// iii. IfAbruptRejectPromise(keys, promiseCapability).
auto keys = TRY_OR_REJECT_WITH_VALUE(global_object, promise_capability, assertion_object.as_object().enumerable_own_property_names(Object::PropertyKind::Key));
// iv. Let supportedAssertions be ! HostGetSupportedImportAssertions().
auto supported_assertions = interpreter.vm().host_get_supported_import_assertions();
// v. For each String key of keys,
for (auto const& key : keys) {
auto property_key = MUST(key.to_property_key(global_object));
// 1. Let value be Get(assertionsObj, key).
// 2. IfAbruptRejectPromise(value, promiseCapability).
auto value = TRY_OR_REJECT_WITH_VALUE(global_object, promise_capability, assertion_object.get(global_object, property_key));
// 3. If Type(value) is not String, then
if (!value.is_string()) {
auto* error = TypeError::create(global_object, String::formatted(ErrorType::NotAString.message(), "Import Assertion option value"));
// a. Perform ! Call(promiseCapability.[[Reject]], undefined, « a newly created TypeError object »).
MUST(call(global_object, *promise_capability.reject, js_undefined(), error));
// b. Return promiseCapability.[[Promise]].
return Value { promise_capability.promise };
}
// 4. If supportedAssertions contains key, then
if (supported_assertions.contains_slow(property_key.to_string())) {
// a. Append { [[Key]]: key, [[Value]]: value } to assertions.
assertions.empend(property_key.to_string(), value.as_string().string());
}
}
}
// e. Sort assertions by the code point order of the [[Key]] of each element. NOTE: This sorting is observable only in that hosts are prohibited from distinguishing among assertions by the order they occur in.
// Note: This is done when constructing the ModuleRequest.
}
// 11. Let moduleRequest be a new ModuleRequest Record { [[Specifier]]: specifierString, [[Assertions]]: assertions }.
ModuleRequest request { specifier_string, assertions };
// 12. Perform ! HostImportModuleDynamically(referencingScriptOrModule, moduleRequest, promiseCapability).
interpreter.vm().host_import_module_dynamically(referencing_script_or_module, move(request), promise_capability);
// 13. Return promiseCapability.[[Promise]].
return Value { promise_capability.promise };
}
// 13.2.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-literals-runtime-semantics-evaluation
Completion StringLiteral::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return the SV of StringLiteral as defined in 12.8.4.2.
return Value { js_string(interpreter.heap(), m_value) };
}
// 13.2.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-literals-runtime-semantics-evaluation
Completion NumericLiteral::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return the NumericValue of NumericLiteral as defined in 12.8.3.
return Value(m_value);
}
// 13.2.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-literals-runtime-semantics-evaluation
Completion BigIntLiteral::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return the NumericValue of NumericLiteral as defined in 12.8.3.
Crypto::SignedBigInteger integer;
if (m_value[0] == '0' && m_value.length() >= 3) {
if (m_value[1] == 'x' || m_value[1] == 'X') {
return Value { js_bigint(interpreter.heap(), Crypto::SignedBigInteger::from_base(16, m_value.substring(2, m_value.length() - 3))) };
} else if (m_value[1] == 'o' || m_value[1] == 'O') {
return Value { js_bigint(interpreter.heap(), Crypto::SignedBigInteger::from_base(8, m_value.substring(2, m_value.length() - 3))) };
} else if (m_value[1] == 'b' || m_value[1] == 'B') {
return Value { js_bigint(interpreter.heap(), Crypto::SignedBigInteger::from_base(2, m_value.substring(2, m_value.length() - 3))) };
}
}
return Value { js_bigint(interpreter.heap(), Crypto::SignedBigInteger::from_base(10, m_value.substring(0, m_value.length() - 1))) };
}
// 13.2.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-literals-runtime-semantics-evaluation
Completion BooleanLiteral::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. If BooleanLiteral is the token false, return false.
// 2. If BooleanLiteral is the token true, return true.
return Value(m_value);
}
// 13.2.3.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-literals-runtime-semantics-evaluation
Completion NullLiteral::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return null.
return js_null();
}
void RegExpLiteral::dump(int indent) const
{
print_indent(indent);
outln("{} (/{}/{})", class_name(), pattern(), flags());
}
// 13.2.7.3 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-regular-expression-literals-runtime-semantics-evaluation
Completion RegExpLiteral::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let pattern be ! CodePointsToString(BodyText of RegularExpressionLiteral).
auto pattern = this->pattern();
// 2. Let flags be ! CodePointsToString(FlagText of RegularExpressionLiteral).
auto flags = this->flags();
// 3. Return RegExpCreate(pattern, flags).
Regex<ECMA262> regex(parsed_regex(), parsed_pattern(), parsed_flags());
return Value { RegExpObject::create(global_object, move(regex), move(pattern), move(flags)) };
}
void ArrayExpression::dump(int indent) const
{
ASTNode::dump(indent);
for (auto& element : m_elements) {
if (element) {
element->dump(indent + 1);
} else {
print_indent(indent + 1);
outln("<empty>");
}
}
}
// 13.2.4.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-array-initializer-runtime-semantics-evaluation
Completion ArrayExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let array be ! ArrayCreate(0).
auto* array = MUST(Array::create(global_object, 0));
// 2. Let len be the result of performing ArrayAccumulation of ElementList with arguments array and 0.
// 3. ReturnIfAbrupt(len).
array->indexed_properties();
size_t index = 0;
for (auto& element : m_elements) {
auto value = Value();
if (element) {
value = TRY(element->execute(interpreter, global_object)).release_value();
if (is<SpreadExpression>(*element)) {
(void)TRY(get_iterator_values(global_object, value, [&](Value iterator_value) -> Optional<Completion> {
array->indexed_properties().put(index++, iterator_value, default_attributes);
return {};
}));
continue;
}
}
array->indexed_properties().put(index++, value, default_attributes);
}
// 4. Return array.
return Value { array };
}
void TemplateLiteral::dump(int indent) const
{
ASTNode::dump(indent);
for (auto& expression : m_expressions)
expression.dump(indent + 1);
}
// 13.2.8.5 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-template-literals-runtime-semantics-evaluation
Completion TemplateLiteral::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
StringBuilder string_builder;
for (auto& expression : m_expressions) {
// 1. Let head be the TV of TemplateHead as defined in 12.8.6.
// 2. Let subRef be the result of evaluating Expression.
// 3. Let sub be ? GetValue(subRef).
auto sub = TRY(expression.execute(interpreter, global_object)).release_value();
// 4. Let middle be ? ToString(sub).
auto string = TRY(sub.to_string(global_object));
string_builder.append(string);
// 5. Let tail be the result of evaluating TemplateSpans.
// 6. ReturnIfAbrupt(tail).
}
// 7. Return the string-concatenation of head, middle, and tail.
return Value { js_string(interpreter.heap(), string_builder.build()) };
}
void TaggedTemplateLiteral::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent + 1);
outln("(Tag)");
m_tag->dump(indent + 2);
print_indent(indent + 1);
outln("(Template Literal)");
m_template_literal->dump(indent + 2);
}
// 13.3.11.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-tagged-templates-runtime-semantics-evaluation
Completion TaggedTemplateLiteral::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
auto tag = TRY(m_tag->execute(interpreter, global_object)).release_value();
auto& expressions = m_template_literal->expressions();
auto* strings = MUST(Array::create(global_object, 0));
MarkedVector<Value> arguments(vm.heap());
arguments.append(strings);
for (size_t i = 0; i < expressions.size(); ++i) {
auto value = TRY(expressions[i].execute(interpreter, global_object)).release_value();
// tag`${foo}` -> "", foo, "" -> tag(["", ""], foo)
// tag`foo${bar}baz${qux}` -> "foo", bar, "baz", qux, "" -> tag(["foo", "baz", ""], bar, qux)
if (i % 2 == 0) {
strings->indexed_properties().append(value);
} else {
arguments.append(value);
}
}
auto* raw_strings = MUST(Array::create(global_object, 0));
for (auto& raw_string : m_template_literal->raw_strings()) {
auto value = TRY(raw_string.execute(interpreter, global_object)).release_value();
raw_strings->indexed_properties().append(value);
}
strings->define_direct_property(vm.names.raw, raw_strings, 0);
return call(global_object, tag, js_undefined(), move(arguments));
}
void TryStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent);
outln("(Block)");
block().dump(indent + 1);
if (handler()) {
print_indent(indent);
outln("(Handler)");
handler()->dump(indent + 1);
}
if (finalizer()) {
print_indent(indent);
outln("(Finalizer)");
finalizer()->dump(indent + 1);
}
}
void CatchClause::dump(int indent) const
{
print_indent(indent);
m_parameter.visit(
[&](FlyString const& parameter) {
if (parameter.is_null())
outln("CatchClause");
else
outln("CatchClause ({})", parameter);
},
[&](NonnullRefPtr<BindingPattern> const& pattern) {
outln("CatchClause");
print_indent(indent);
outln("(Parameter)");
pattern->dump(indent + 2);
});
body().dump(indent + 1);
}
void ThrowStatement::dump(int indent) const
{
ASTNode::dump(indent);
argument().dump(indent + 1);
}
// 14.15.3 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-try-statement-runtime-semantics-evaluation
Completion TryStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
// 14.15.2 Runtime Semantics: CatchClauseEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-catchclauseevaluation
auto catch_clause_evaluation = [&](Value thrown_value) {
// 1. Let oldEnv be the running execution context's LexicalEnvironment.
auto* old_environment = vm.running_execution_context().lexical_environment;
// 2. Let catchEnv be NewDeclarativeEnvironment(oldEnv).
auto* catch_environment = new_declarative_environment(*old_environment);
m_handler->parameter().visit(
[&](FlyString const& parameter) {
// 3. For each element argName of the BoundNames of CatchParameter, do
// a. Perform ! catchEnv.CreateMutableBinding(argName, false).
MUST(catch_environment->create_mutable_binding(global_object, parameter, false));
},
[&](NonnullRefPtr<BindingPattern> const& pattern) {
// 3. For each element argName of the BoundNames of CatchParameter, do
pattern->for_each_bound_name([&](auto& name) {
// a. Perform ! catchEnv.CreateMutableBinding(argName, false).
MUST(catch_environment->create_mutable_binding(global_object, name, false));
});
});
// 4. Set the running execution context's LexicalEnvironment to catchEnv.
vm.running_execution_context().lexical_environment = catch_environment;
// 5. Let status be BindingInitialization of CatchParameter with arguments thrownValue and catchEnv.
auto status = m_handler->parameter().visit(
[&](FlyString const& parameter) {
return catch_environment->initialize_binding(global_object, parameter, thrown_value);
},
[&](NonnullRefPtr<BindingPattern> const& pattern) {
return vm.binding_initialization(pattern, thrown_value, catch_environment, global_object);
});
// 6. If status is an abrupt completion, then
if (status.is_error()) {
// a. Set the running execution context's LexicalEnvironment to oldEnv.
vm.running_execution_context().lexical_environment = old_environment;
// b. Return Completion(status).
return status.release_error();
}
// 7. Let B be the result of evaluating Block.
auto handler_result = m_handler->body().execute(interpreter, global_object);
// 8. Set the running execution context's LexicalEnvironment to oldEnv.
vm.running_execution_context().lexical_environment = old_environment;
// 9. Return Completion(B).
return handler_result;
};
Completion result;
// 1. Let B be the result of evaluating Block.
auto block_result = m_block->execute(interpreter, global_object);
// TryStatement : try Block Catch
// TryStatement : try Block Catch Finally
if (m_handler) {
// 2. If B.[[Type]] is throw, let C be CatchClauseEvaluation of Catch with argument B.[[Value]].
if (block_result.type() == Completion::Type::Throw)
result = catch_clause_evaluation(*block_result.value());
// 3. Else, let C be B.
else
result = move(block_result);
} else {
// TryStatement : try Block Finally
// This variant doesn't have C & uses B in the finalizer step.
result = move(block_result);
}
// TryStatement : try Block Finally
// TryStatement : try Block Catch Finally
if (m_finalizer) {
// 4. Let F be the result of evaluating Finally.
auto finalizer_result = m_finalizer->execute(interpreter, global_object);
// 5. If F.[[Type]] is normal, set F to C.
if (finalizer_result.type() == Completion::Type::Normal)
finalizer_result = move(result);
// 6. Return Completion(UpdateEmpty(F, undefined)).
return finalizer_result.update_empty(js_undefined());
}
// 4. Return Completion(UpdateEmpty(C, undefined)).
return result.update_empty(js_undefined());
}
Completion CatchClause::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// NOTE: CatchClause execution is handled by TryStatement.
VERIFY_NOT_REACHED();
return {};
}
// 14.14.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-throw-statement-runtime-semantics-evaluation
Completion ThrowStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let exprRef be the result of evaluating Expression.
// 2. Let exprValue be ? GetValue(exprRef).
auto value = TRY(m_argument->execute(interpreter, global_object)).release_value();
// 3. Return ThrowCompletion(exprValue).
return throw_completion(value);
}
// 14.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-statement-semantics-runtime-semantics-evaluation
// BreakableStatement : SwitchStatement
Completion SwitchStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
// 1. Let newLabelSet be a new empty List.
// 2. Return the result of performing LabelledEvaluation of this BreakableStatement with argument newLabelSet.
return labelled_evaluation(interpreter, global_object, *this, {});
}
// NOTE: Since we don't have the 'BreakableStatement' from the spec as a separate ASTNode that wraps IterationStatement / SwitchStatement,
// execute() needs to take care of LabelledEvaluation, which in turn calls execute_impl().
// 14.12.4 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-switch-statement-runtime-semantics-evaluation
Completion SwitchStatement::execute_impl(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
auto& vm = interpreter.vm();
// 14.12.3 CaseClauseIsSelected ( C, input ), https://tc39.es/ecma262/#sec-runtime-semantics-caseclauseisselected
auto case_clause_is_selected = [&](auto const& case_clause, auto input) -> ThrowCompletionOr<bool> {
// 1. Assert: C is an instance of the production CaseClause : case Expression : StatementList[opt] .
VERIFY(case_clause.test());
// 2. Let exprRef be the result of evaluating the Expression of C.
// 3. Let clauseSelector be ? GetValue(exprRef).
auto clause_selector = TRY(case_clause.test()->execute(interpreter, global_object)).release_value();
// 4. Return IsStrictlyEqual(input, clauseSelector).
return is_strictly_equal(input, clause_selector);
};
// 14.12.2 Runtime Semantics: CaseBlockEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-caseblockevaluation
auto case_block_evaluation = [&](auto input) {
// CaseBlock : { }
if (m_cases.is_empty()) {
// 1. Return NormalCompletion(undefined).
return normal_completion(js_undefined());
}
NonnullRefPtrVector<SwitchCase> case_clauses_1;
NonnullRefPtrVector<SwitchCase> case_clauses_2;
RefPtr<SwitchCase> default_clause;
for (auto const& switch_case : m_cases) {
if (!switch_case.test())
default_clause = switch_case;
else if (!default_clause)
case_clauses_1.append(switch_case);
else
case_clauses_2.append(switch_case);
}
// CaseBlock : { CaseClauses }
if (!default_clause) {
VERIFY(!case_clauses_1.is_empty());
VERIFY(case_clauses_2.is_empty());
// 1. Let V be undefined.
auto last_value = js_undefined();
// 2. Let A be the List of CaseClause items in CaseClauses, in source text order.
// NOTE: A is case_clauses_1.
// 3. Let found be false.
auto found = false;
// 4. For each CaseClause C of A, do
for (auto const& case_clause : case_clauses_1) {
// a. If found is false, then
if (!found) {
// i. Set found to ? CaseClauseIsSelected(C, input).
found = TRY(case_clause_is_selected(case_clause, input));
}
// b. If found is true, then
if (found) {
// i. Let R be the result of evaluating C.
auto result = case_clause.evaluate_statements(interpreter, global_object);
// ii. If R.[[Value]] is not empty, set V to R.[[Value]].
if (result.value().has_value())
last_value = *result.value();
// iii. If R is an abrupt completion, return Completion(UpdateEmpty(R, V)).
if (result.is_abrupt())
return result.update_empty(last_value);
}
}
// 5. Return NormalCompletion(V).
return normal_completion(last_value);
}
// CaseBlock : { CaseClauses[opt] DefaultClause CaseClauses[opt] }
else {
// 1. Let V be undefined.
auto last_value = js_undefined();
// 2. If the first CaseClauses is present, then
// a. Let A be the List of CaseClause items in the first CaseClauses, in source text order.
// 3. Else,
// a. Let A be « ».
// NOTE: A is case_clauses_1.
// 4. Let found be false.
auto found = false;
// 5. For each CaseClause C of A, do
for (auto const& case_clause : case_clauses_1) {
// a. If found is false, then
if (!found) {
// i. Set found to ? CaseClauseIsSelected(C, input).
found = TRY(case_clause_is_selected(case_clause, input));
}
// b. If found is true, then
if (found) {
// i. Let R be the result of evaluating C.
auto result = case_clause.evaluate_statements(interpreter, global_object);
// ii. If R.[[Value]] is not empty, set V to R.[[Value]].
if (result.value().has_value())
last_value = *result.value();
// iii. If R is an abrupt completion, return Completion(UpdateEmpty(R, V)).
if (result.is_abrupt())
return result.update_empty(last_value);
}
}
// 6. Let foundInB be false.
auto found_in_b = false;
// 7. If the second CaseClauses is present, then
// a. Let B be the List of CaseClause items in the second CaseClauses, in source text order.
// 8. Else,
// a. Let B be « ».
// NOTE: B is case_clauses_2.
// 9. If found is false, then
if (!found) {
// a. For each CaseClause C of B, do
for (auto const& case_clause : case_clauses_2) {
// i. If foundInB is false, then
if (!found_in_b) {
// 1. Set foundInB to ? CaseClauseIsSelected(C, input).
found_in_b = TRY(case_clause_is_selected(case_clause, input));
}
// ii. If foundInB is true, then
if (found_in_b) {
// 1. Let R be the result of evaluating CaseClause C.
auto result = case_clause.evaluate_statements(interpreter, global_object);
// 2. If R.[[Value]] is not empty, set V to R.[[Value]].
if (result.value().has_value())
last_value = *result.value();
// 3. If R is an abrupt completion, return Completion(UpdateEmpty(R, V)).
if (result.is_abrupt())
return result.update_empty(last_value);
}
}
}
// 10. If foundInB is true, return NormalCompletion(V).
if (found_in_b)
return normal_completion(last_value);
// 11. Let R be the result of evaluating DefaultClause.
auto result = default_clause->evaluate_statements(interpreter, global_object);
// 12. If R.[[Value]] is not empty, set V to R.[[Value]].
if (result.value().has_value())
last_value = *result.value();
// 13. If R is an abrupt completion, return Completion(UpdateEmpty(R, V)).
if (result.is_abrupt())
return result.update_empty(last_value);
// 14. NOTE: The following is another complete iteration of the second CaseClauses.
// 15. For each CaseClause C of B, do
for (auto const& case_clause : case_clauses_2) {
// a. Let R be the result of evaluating CaseClause C.
result = case_clause.evaluate_statements(interpreter, global_object);
// b. If R.[[Value]] is not empty, set V to R.[[Value]].
if (result.value().has_value())
last_value = *result.value();
// c. If R is an abrupt completion, return Completion(UpdateEmpty(R, V)).
if (result.is_abrupt())
return result.update_empty(last_value);
}
// 16. Return NormalCompletion(V).
return normal_completion(last_value);
}
VERIFY_NOT_REACHED();
};
// SwitchStatement : switch ( Expression ) CaseBlock
// 1. Let exprRef be the result of evaluating Expression.
// 2. Let switchValue be ? GetValue(exprRef).
auto switch_value = TRY(m_discriminant->execute(interpreter, global_object)).release_value();
// 3. Let oldEnv be the running execution context's LexicalEnvironment.
auto* old_environment = interpreter.lexical_environment();
// Optimization: Avoid creating a lexical environment if there are no lexical declarations.
if (has_lexical_declarations()) {
// 4. Let blockEnv be NewDeclarativeEnvironment(oldEnv).
auto* block_environment = new_declarative_environment(*old_environment);
// 5. Perform BlockDeclarationInstantiation(CaseBlock, blockEnv).
block_declaration_instantiation(global_object, block_environment);
// 6. Set the running execution context's LexicalEnvironment to blockEnv.
vm.running_execution_context().lexical_environment = block_environment;
}
// 7. Let R be CaseBlockEvaluation of CaseBlock with argument switchValue.
auto result = case_block_evaluation(switch_value);
// 8. Set the running execution context's LexicalEnvironment to oldEnv.
vm.running_execution_context().lexical_environment = old_environment;
// 9. Return R.
return result;
}
Completion SwitchCase::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// NOTE: SwitchCase execution is handled by SwitchStatement.
VERIFY_NOT_REACHED();
return {};
}
// 14.9.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-break-statement-runtime-semantics-evaluation
Completion BreakStatement::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// BreakStatement : break ;
if (m_target_label.is_null()) {
// 1. Return Completion { [[Type]]: break, [[Value]]: empty, [[Target]]: empty }.
return { Completion::Type::Break, {}, {} };
}
// BreakStatement : break LabelIdentifier ;
// 1. Let label be the StringValue of LabelIdentifier.
// 2. Return Completion { [[Type]]: break, [[Value]]: empty, [[Target]]: label }.
return { Completion::Type::Break, {}, m_target_label };
}
// 14.8.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-continue-statement-runtime-semantics-evaluation
Completion ContinueStatement::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// ContinueStatement : continue ;
if (m_target_label.is_null()) {
// 1. Return Completion { [[Type]]: continue, [[Value]]: empty, [[Target]]: empty }.
return { Completion::Type::Continue, {}, {} };
}
// ContinueStatement : continue LabelIdentifier ;
// 1. Let label be the StringValue of LabelIdentifier.
// 2. Return Completion { [[Type]]: continue, [[Value]]: empty, [[Target]]: label }.
return { Completion::Type::Continue, {}, m_target_label };
}
void SwitchStatement::dump(int indent) const
{
ASTNode::dump(indent);
m_discriminant->dump(indent + 1);
for (auto& switch_case : m_cases) {
switch_case.dump(indent + 1);
}
}
void SwitchCase::dump(int indent) const
{
print_indent(indent + 1);
if (m_test) {
outln("(Test)");
m_test->dump(indent + 2);
} else {
outln("(Default)");
}
print_indent(indent + 1);
outln("(Consequent)");
ScopeNode::dump(indent + 2);
}
// 13.14.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-conditional-operator-runtime-semantics-evaluation
Completion ConditionalExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Let lref be the result of evaluating ShortCircuitExpression.
// 2. Let lval be ! ToBoolean(? GetValue(lref)).
auto test_result = TRY(m_test->execute(interpreter, global_object)).release_value();
// 3. If lval is true, then
if (test_result.to_boolean()) {
// a. Let trueRef be the result of evaluating the first AssignmentExpression.
// b. Return ? GetValue(trueRef).
return m_consequent->execute(interpreter, global_object);
}
// 4. Else,
else {
// a. Let falseRef be the result of evaluating the second AssignmentExpression.
// b. Return ? GetValue(falseRef).
return m_alternate->execute(interpreter, global_object);
}
}
void ConditionalExpression::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent + 1);
outln("(Test)");
m_test->dump(indent + 2);
print_indent(indent + 1);
outln("(Consequent)");
m_consequent->dump(indent + 2);
print_indent(indent + 1);
outln("(Alternate)");
m_alternate->dump(indent + 2);
}
void SequenceExpression::dump(int indent) const
{
ASTNode::dump(indent);
for (auto& expression : m_expressions)
expression.dump(indent + 1);
}
// 13.16.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-comma-operator-runtime-semantics-evaluation
Completion SequenceExpression::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// NOTE: Not sure why the last node is an AssignmentExpression in the spec :yakfused:
// 1. Let lref be the result of evaluating Expression.
// 2. Perform ? GetValue(lref).
// 3. Let rref be the result of evaluating AssignmentExpression.
// 4. Return ? GetValue(rref).
Value last_value;
for (auto const& expression : m_expressions)
last_value = TRY(expression.execute(interpreter, global_object)).release_value();
return { move(last_value) };
}
// 14.16.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-debugger-statement-runtime-semantics-evaluation
Completion DebuggerStatement::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
Completion result;
// 1. If an implementation-defined debugging facility is available and enabled, then
if (false) {
// a. Perform an implementation-defined debugging action.
// b. Let result be an implementation-defined Completion value.
}
// 2. Else,
else {
// a. Let result be NormalCompletion(empty).
result = normal_completion({});
}
// 3. Return result.
return result;
}
ThrowCompletionOr<void> ScopeNode::for_each_lexically_scoped_declaration(ThrowCompletionOrVoidCallback<Declaration const&>&& callback) const
{
for (auto& declaration : m_lexical_declarations)
TRY(callback(declaration));
return {};
}
ThrowCompletionOr<void> ScopeNode::for_each_lexically_declared_name(ThrowCompletionOrVoidCallback<FlyString const&>&& callback) const
{
for (auto const& declaration : m_lexical_declarations) {
TRY(declaration.for_each_bound_name([&](auto const& name) {
return callback(name);
}));
}
return {};
}
ThrowCompletionOr<void> ScopeNode::for_each_var_declared_name(ThrowCompletionOrVoidCallback<FlyString const&>&& callback) const
{
for (auto& declaration : m_var_declarations) {
TRY(declaration.for_each_bound_name([&](auto const& name) {
return callback(name);
}));
}
return {};
}
ThrowCompletionOr<void> ScopeNode::for_each_var_function_declaration_in_reverse_order(ThrowCompletionOrVoidCallback<FunctionDeclaration const&>&& callback) const
{
for (ssize_t i = m_var_declarations.size() - 1; i >= 0; i--) {
auto& declaration = m_var_declarations[i];
if (is<FunctionDeclaration>(declaration))
TRY(callback(static_cast<FunctionDeclaration const&>(declaration)));
}
return {};
}
ThrowCompletionOr<void> ScopeNode::for_each_var_scoped_variable_declaration(ThrowCompletionOrVoidCallback<VariableDeclaration const&>&& callback) const
{
for (auto& declaration : m_var_declarations) {
if (!is<FunctionDeclaration>(declaration)) {
VERIFY(is<VariableDeclaration>(declaration));
TRY(callback(static_cast<VariableDeclaration const&>(declaration)));
}
}
return {};
}
ThrowCompletionOr<void> ScopeNode::for_each_function_hoistable_with_annexB_extension(ThrowCompletionOrVoidCallback<FunctionDeclaration&>&& callback) const
{
for (auto& function : m_functions_hoistable_with_annexB_extension) {
// We need const_cast here since it might have to set a property on function declaration.
TRY(callback(const_cast<FunctionDeclaration&>(function)));
}
return {};
}
void ScopeNode::add_lexical_declaration(NonnullRefPtr<Declaration> declaration)
{
m_lexical_declarations.append(move(declaration));
}
void ScopeNode::add_var_scoped_declaration(NonnullRefPtr<Declaration> declaration)
{
m_var_declarations.append(move(declaration));
}
void ScopeNode::add_hoisted_function(NonnullRefPtr<FunctionDeclaration> declaration)
{
m_functions_hoistable_with_annexB_extension.append(move(declaration));
}
// 16.2.1.11 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-module-semantics-runtime-semantics-evaluation
Completion ImportStatement::execute(Interpreter& interpreter, GlobalObject&) const
{
InterpreterNodeScope node_scope { interpreter, *this };
// 1. Return NormalCompletion(empty).
return normal_completion({});
}
FlyString ExportStatement::local_name_for_default = "*default*";
// 16.2.3.7 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-exports-runtime-semantics-evaluation
Completion ExportStatement::execute(Interpreter& interpreter, GlobalObject& global_object) const
{
InterpreterNodeScope node_scope { interpreter, *this };
if (!is_default_export()) {
if (m_statement) {
// 1. Return the result of evaluating <Thing>.
return m_statement->execute(interpreter, global_object);
}
// 1. Return NormalCompletion(empty).
return normal_completion({});
}
VERIFY(m_statement);
// ExportDeclaration : export default HoistableDeclaration
if (is<FunctionDeclaration>(*m_statement)) {
// 1. Return the result of evaluating HoistableDeclaration.
return m_statement->execute(interpreter, global_object);
}
// ExportDeclaration : export default ClassDeclaration
// ClassDeclaration: class BindingIdentifier[?Yield, ?Await] ClassTail[?Yield, ?Await]
if (is<ClassDeclaration>(*m_statement)) {
auto const& class_declaration = static_cast<ClassDeclaration const&>(*m_statement);
// 1. Let value be ? BindingClassDeclarationEvaluation of ClassDeclaration.
auto value = TRY(binding_class_declaration_evaluation(interpreter, global_object, class_declaration.m_class_expression));
// 2. Let className be the sole element of BoundNames of ClassDeclaration.
// 3. If className is "*default*", then
// Note: We never go into step 3. since a ClassDeclaration always has a name and "*default*" is not a class name.
(void)value;
// 4. Return NormalCompletion(empty).
return normal_completion({});
}
// ExportDeclaration : export default ClassDeclaration
// ClassDeclaration: [+Default] class ClassTail [?Yield, ?Await]
if (is<ClassExpression>(*m_statement)) {
auto& class_expression = static_cast<ClassExpression const&>(*m_statement);
// 1. Let value be ? BindingClassDeclarationEvaluation of ClassDeclaration.
auto value = TRY(binding_class_declaration_evaluation(interpreter, global_object, class_expression));
// 2. Let className be the sole element of BoundNames of ClassDeclaration.
// 3. If className is "*default*", then
if (!class_expression.has_name()) {
// Note: This can only occur if the class does not have a name since "*default*" is normally not valid.
// a. Let env be the running execution context's LexicalEnvironment.
auto* env = interpreter.lexical_environment();
// b. Perform ? InitializeBoundName("*default*", value, env).
TRY(initialize_bound_name(global_object, ExportStatement::local_name_for_default, value, env));
}
// 4. Return NormalCompletion(empty).
return normal_completion({});
}
// ExportDeclaration : export default AssignmentExpression ;
// 1. If IsAnonymousFunctionDefinition(AssignmentExpression) is true, then
// a. Let value be ? NamedEvaluation of AssignmentExpression with argument "default".
// 2. Else,
// a. Let rhs be the result of evaluating AssignmentExpression.
// b. Let value be ? GetValue(rhs).
auto value = TRY(interpreter.vm().named_evaluation_if_anonymous_function(global_object, *m_statement, "default"));
// 3. Let env be the running execution context's LexicalEnvironment.
auto* env = interpreter.lexical_environment();
// 4. Perform ? InitializeBoundName("*default*", value, env).
TRY(initialize_bound_name(global_object, ExportStatement::local_name_for_default, value, env));
// 5. Return NormalCompletion(empty).
return normal_completion({});
}
static void dump_assert_clauses(ModuleRequest const& request)
{
if (!request.assertions.is_empty()) {
out("[ ");
for (auto& assertion : request.assertions)
out("{}: {}, ", assertion.key, assertion.value);
out(" ]");
}
}
void ExportStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent + 1);
outln("(ExportEntries)");
auto string_or_null = [](String const& string) -> String {
if (string.is_empty()) {
return "null";
}
return String::formatted("\"{}\"", string);
};
for (auto& entry : m_entries) {
print_indent(indent + 2);
out("ExportName: {}, ImportName: {}, LocalName: {}, ModuleRequest: ",
string_or_null(entry.export_name),
entry.is_module_request() ? string_or_null(entry.local_or_import_name) : "null",
entry.is_module_request() ? "null" : string_or_null(entry.local_or_import_name));
if (entry.is_module_request()) {
out("{}", entry.m_module_request->module_specifier);
dump_assert_clauses(*entry.m_module_request);
outln();
} else {
outln("null");
}
}
if (m_statement) {
print_indent(indent + 1);
outln("(Statement)");
m_statement->dump(indent + 2);
}
}
void ImportStatement::dump(int indent) const
{
ASTNode::dump(indent);
print_indent(indent + 1);
if (m_entries.is_empty()) {
// direct from "module" import
outln("Entire module '{}'", m_module_request.module_specifier);
dump_assert_clauses(m_module_request);
} else {
outln("(ExportEntries) from {}", m_module_request.module_specifier);
dump_assert_clauses(m_module_request);
for (auto& entry : m_entries) {
print_indent(indent + 2);
outln("ImportName: {}, LocalName: {}", entry.import_name, entry.local_name);
}
}
}
bool ExportStatement::has_export(FlyString const& export_name) const
{
return any_of(m_entries.begin(), m_entries.end(), [&](auto& entry) {
return entry.export_name == export_name;
});
}
bool ImportStatement::has_bound_name(FlyString const& name) const
{
return any_of(m_entries.begin(), m_entries.end(), [&](auto& entry) {
return entry.local_name == name;
});
}
// 14.2.3 BlockDeclarationInstantiation ( code, env ), https://tc39.es/ecma262/#sec-blockdeclarationinstantiation
void ScopeNode::block_declaration_instantiation(GlobalObject& global_object, Environment* environment) const
{
// See also B.3.2.6 Changes to BlockDeclarationInstantiation, https://tc39.es/ecma262/#sec-web-compat-blockdeclarationinstantiation
VERIFY(environment);
auto* private_environment = global_object.vm().running_execution_context().private_environment;
// Note: All the calls here are ! and thus we do not need to TRY this callback.
for_each_lexically_scoped_declaration([&](Declaration const& declaration) {
auto is_constant_declaration = declaration.is_constant_declaration();
declaration.for_each_bound_name([&](auto const& name) {
if (is_constant_declaration) {
MUST(environment->create_immutable_binding(global_object, name, true));
} else {
if (!MUST(environment->has_binding(name)))
MUST(environment->create_mutable_binding(global_object, name, false));
}
});
if (is<FunctionDeclaration>(declaration)) {
auto& function_declaration = static_cast<FunctionDeclaration const&>(declaration);
auto* function = ECMAScriptFunctionObject::create(global_object, function_declaration.name(), function_declaration.source_text(), function_declaration.body(), function_declaration.parameters(), function_declaration.function_length(), environment, private_environment, function_declaration.kind(), function_declaration.is_strict_mode(), function_declaration.might_need_arguments_object(), function_declaration.contains_direct_call_to_eval());
VERIFY(is<DeclarativeEnvironment>(*environment));
static_cast<DeclarativeEnvironment&>(*environment).initialize_or_set_mutable_binding({}, global_object, function_declaration.name(), function);
}
});
}
// 16.1.7 GlobalDeclarationInstantiation ( script, env ), https://tc39.es/ecma262/#sec-globaldeclarationinstantiation
ThrowCompletionOr<void> Program::global_declaration_instantiation(Interpreter& interpreter, GlobalObject& global_object, GlobalEnvironment& global_environment) const
{
// 1. Let lexNames be the LexicallyDeclaredNames of script.
// 2. Let varNames be the VarDeclaredNames of script.
// 3. For each element name of lexNames, do
TRY(for_each_lexically_declared_name([&](FlyString const& name) -> ThrowCompletionOr<void> {
// a. If env.HasVarDeclaration(name) is true, throw a SyntaxError exception.
if (global_environment.has_var_declaration(name))
return interpreter.vm().throw_completion<SyntaxError>(global_object, ErrorType::TopLevelVariableAlreadyDeclared, name);
// b. If env.HasLexicalDeclaration(name) is true, throw a SyntaxError exception.
if (global_environment.has_lexical_declaration(name))
return interpreter.vm().throw_completion<SyntaxError>(global_object, ErrorType::TopLevelVariableAlreadyDeclared, name);
// c. Let hasRestrictedGlobal be ? env.HasRestrictedGlobalProperty(name).
auto has_restricted_global = TRY(global_environment.has_restricted_global_property(name));
// d. If hasRestrictedGlobal is true, throw a SyntaxError exception.
if (has_restricted_global)
return interpreter.vm().throw_completion<SyntaxError>(global_object, ErrorType::RestrictedGlobalProperty, name);
return {};
}));
// 4. For each element name of varNames, do
TRY(for_each_var_declared_name([&](auto const& name) -> ThrowCompletionOr<void> {
// a. If env.HasLexicalDeclaration(name) is true, throw a SyntaxError exception.
if (global_environment.has_lexical_declaration(name))
return interpreter.vm().throw_completion<SyntaxError>(global_object, ErrorType::TopLevelVariableAlreadyDeclared, name);
return {};
}));
// 5. Let varDeclarations be the VarScopedDeclarations of script.
// 6. Let functionsToInitialize be a new empty List.
Vector<FunctionDeclaration const&> functions_to_initialize;
// 7. Let declaredFunctionNames be a new empty List.
HashTable<FlyString> declared_function_names;
// 8. For each element d of varDeclarations, in reverse List order, do
TRY(for_each_var_function_declaration_in_reverse_order([&](FunctionDeclaration const& function) -> ThrowCompletionOr<void> {
// a. If d is neither a VariableDeclaration nor a ForBinding nor a BindingIdentifier, then
// i. Assert: d is either a FunctionDeclaration, a GeneratorDeclaration, an AsyncFunctionDeclaration, or an AsyncGeneratorDeclaration.
// Note: This is checked in for_each_var_function_declaration_in_reverse_order.
// ii. NOTE: If there are multiple function declarations for the same name, the last declaration is used.
// iii. Let fn be the sole element of the BoundNames of d.
// iv. If fn is not an element of declaredFunctionNames, then
if (declared_function_names.set(function.name()) != AK::HashSetResult::InsertedNewEntry)
return {};
// 1. Let fnDefinable be ? env.CanDeclareGlobalFunction(fn).
auto function_definable = TRY(global_environment.can_declare_global_function(function.name()));
// 2. If fnDefinable is false, throw a TypeError exception.
if (!function_definable)
return interpreter.vm().throw_completion<TypeError>(global_object, ErrorType::CannotDeclareGlobalFunction, function.name());
// 3. Append fn to declaredFunctionNames.
// Note: Already done in step iv. above.
// 4. Insert d as the first element of functionsToInitialize.
functions_to_initialize.append(function);
return {};
}));
// 9. Let declaredVarNames be a new empty List.
HashTable<FlyString> declared_var_names;
// 10. For each element d of varDeclarations, do
TRY(for_each_var_scoped_variable_declaration([&](Declaration const& declaration) {
// a. If d is a VariableDeclaration, a ForBinding, or a BindingIdentifier, then
// Note: This is done in for_each_var_scoped_variable_declaration.
// i. For each String vn of the BoundNames of d, do
return declaration.for_each_bound_name([&](auto const& name) -> ThrowCompletionOr<void> {
// 1. If vn is not an element of declaredFunctionNames, then
if (declared_function_names.contains(name))
return {};
// a. Let vnDefinable be ? env.CanDeclareGlobalVar(vn).
auto var_definable = TRY(global_environment.can_declare_global_var(name));
// b. If vnDefinable is false, throw a TypeError exception.
if (!var_definable)
return interpreter.vm().throw_completion<TypeError>(global_object, ErrorType::CannotDeclareGlobalVariable, name);
// c. If vn is not an element of declaredVarNames, then
// i. Append vn to declaredVarNames.
declared_var_names.set(name);
return {};
});
}));
// 11. NOTE: No abnormal terminations occur after this algorithm step if the global object is an ordinary object. However, if the global object is a Proxy exotic object it may exhibit behaviours that cause abnormal terminations in some of the following steps.
// 12. NOTE: Annex B.3.2.2 adds additional steps at this point.
// 12. Let strict be IsStrict of script.
// 13. If strict is false, then
if (!m_is_strict_mode) {
// a. Let declaredFunctionOrVarNames be the list-concatenation of declaredFunctionNames and declaredVarNames.
// b. For each FunctionDeclaration f that is directly contained in the StatementList of a Block, CaseClause, or DefaultClause Contained within script, do
TRY(for_each_function_hoistable_with_annexB_extension([&](FunctionDeclaration& function_declaration) -> ThrowCompletionOr<void> {
// i. Let F be StringValue of the BindingIdentifier of f.
auto& function_name = function_declaration.name();
// ii. If replacing the FunctionDeclaration f with a VariableStatement that has F as a BindingIdentifier would not produce any Early Errors for script, then
// Note: This step is already performed during parsing and for_each_function_hoistable_with_annexB_extension so this always passes here.
// 1. If env.HasLexicalDeclaration(F) is false, then
if (global_environment.has_lexical_declaration(function_name))
return {};
// a. Let fnDefinable be ? env.CanDeclareGlobalVar(F).
auto function_definable = TRY(global_environment.can_declare_global_function(function_name));
// b. If fnDefinable is true, then
if (!function_definable)
return {};
// i. NOTE: A var binding for F is only instantiated here if it is neither a VarDeclaredName nor the name of another FunctionDeclaration.
// ii. If declaredFunctionOrVarNames does not contain F, then
if (!declared_function_names.contains(function_name) && !declared_var_names.contains(function_name)) {
// i. Perform ? env.CreateGlobalVarBinding(F, false).
TRY(global_environment.create_global_var_binding(function_name, false));
// ii. Append F to declaredFunctionOrVarNames.
declared_function_names.set(function_name);
}
// iii. When the FunctionDeclaration f is evaluated, perform the following steps in place of the FunctionDeclaration Evaluation algorithm provided in 15.2.6:
// i. Let genv be the running execution context's VariableEnvironment.
// ii. Let benv be the running execution context's LexicalEnvironment.
// iii. Let fobj be ! benv.GetBindingValue(F, false).
// iv. Perform ? genv.SetMutableBinding(F, fobj, false).
// v. Return NormalCompletion(empty).
function_declaration.set_should_do_additional_annexB_steps();
return {};
}));
// We should not use declared function names below here anymore since these functions are not in there in the spec.
declared_function_names.clear();
}
// 13. Let lexDeclarations be the LexicallyScopedDeclarations of script.
// 14. Let privateEnv be null.
PrivateEnvironment* private_environment = nullptr;
// 15. For each element d of lexDeclarations, do
TRY(for_each_lexically_scoped_declaration([&](Declaration const& declaration) {
// a. NOTE: Lexically declared names are only instantiated here but not initialized.
// b. For each element dn of the BoundNames of d, do
return declaration.for_each_bound_name([&](auto const& name) -> ThrowCompletionOr<void> {
// i. If IsConstantDeclaration of d is true, then
if (declaration.is_constant_declaration()) {
// 1. Perform ? env.CreateImmutableBinding(dn, true).
TRY(global_environment.create_immutable_binding(global_object, name, true));
}
// ii. Else,
else {
// 1. Perform ? env.CreateMutableBinding(dn, false).
TRY(global_environment.create_mutable_binding(global_object, name, false));
}
return {};
});
}));
// 16. For each Parse Node f of functionsToInitialize, do
for (auto& declaration : functions_to_initialize) {
// a. Let fn be the sole element of the BoundNames of f.
// b. Let fo be InstantiateFunctionObject of f with arguments env and privateEnv.
auto* function = ECMAScriptFunctionObject::create(global_object, declaration.name(), declaration.source_text(), declaration.body(), declaration.parameters(), declaration.function_length(), &global_environment, private_environment, declaration.kind(), declaration.is_strict_mode(), declaration.might_need_arguments_object(), declaration.contains_direct_call_to_eval());
// c. Perform ? env.CreateGlobalFunctionBinding(fn, fo, false).
TRY(global_environment.create_global_function_binding(declaration.name(), function, false));
}
// 17. For each String vn of declaredVarNames, do
for (auto& var_name : declared_var_names) {
// a. Perform ? env.CreateGlobalVarBinding(vn, false).
TRY(global_environment.create_global_var_binding(var_name, false));
}
// 18. Return NormalCompletion(empty).
return {};
}
ModuleRequest::ModuleRequest(FlyString module_specifier_, Vector<Assertion> assertions_)
: module_specifier(move(module_specifier_))
, assertions(move(assertions_))
{
// Perform step 10.e. from EvaluateImportCall, https://tc39.es/proposal-import-assertions/#sec-evaluate-import-call
// or step 2. from 2.7 Static Semantics: AssertClauseToAssertions, https://tc39.es/proposal-import-assertions/#sec-assert-clause-to-assertions
// e. / 2. Sort assertions by the code point order of the [[Key]] of each element.
// NOTE: This sorting is observable only in that hosts are prohibited from distinguishing among assertions by the order they occur in.
quick_sort(assertions, [](Assertion const& lhs, Assertion const& rhs) {
return lhs.key < rhs.key;
});
}
}