/* * Copyright (c) 2020-2021, Andreas Kling * Copyright (c) 2020-2022, Linus Groh * Copyright (c) 2021-2022, David Tuin * * SPDX-License-Identifier: BSD-2-Clause */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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. auto const* typename_ptr = typeid(*this).name(); return demangle({ typename_ptr, strlen(typename_ptr) }).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(function) && function.name().is_empty()) static_cast(function).set_name(name); } static ThrowCompletionOr 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) const { auto completion = normal_completion({}); for (auto const& node : children()) { completion = node.execute(interpreter).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, IterationStatement const& statement, Vector const& label_set) { // 1. Let stmtResult be Completion(LoopEvaluation of IterationStatement with argument labelSet). auto result = statement.loop_evaluation(interpreter, 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 ? 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, SwitchStatement const& statement, Vector const&) { // 1. Let stmtResult be the result of evaluating SwitchStatement. auto result = statement.execute_impl(interpreter); // 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 ? 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, LabelledStatement const& statement, Vector 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> new_label_set; if (is(labelled_item) || is(labelled_item) || is(labelled_item)) { new_label_set = label_set; new_label_set->append(label); } // 3. Let stmtResult be Completion(LabelledEvaluation of LabelledItem with argument newLabelSet). Completion result; if (is(labelled_item)) result = labelled_evaluation(interpreter, static_cast(labelled_item), *new_label_set); else if (is(labelled_item)) result = labelled_evaluation(interpreter, static_cast(labelled_item), *new_label_set); else if (is(labelled_item)) result = labelled_evaluation(interpreter, static_cast(labelled_item), *new_label_set); else result = labelled_item.execute(interpreter); // 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 ? stmtResult. return result; } // 14.13.3 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-labelled-statements-runtime-semantics-evaluation Completion LabelledStatement::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; // 1. Return ? LabelledEvaluation of this LabelledStatement with argument « ». return labelled_evaluation(interpreter, *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) 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); } // 14.2.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-block-runtime-semantics-evaluation Completion BlockStatement::execute(Interpreter& interpreter) 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(interpreter, block_environment); vm.running_execution_context().lexical_environment = block_environment; } else { restore_environment.disarm(); } return evaluate_statements(interpreter); } Completion Program::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; return evaluate_statements(interpreter); } // 15.2.6 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-function-definitions-runtime-semantics-evaluation Completion FunctionDeclaration::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); 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(vm, name(), false)); // iv. Perform ? genv.SetMutableBinding(F, fobj, false). TRY(variable_environment->set_mutable_binding(vm, name(), function_object, false)); // v. Return unused. return Optional {}; } // 1. Return unused. return Optional {}; } // 15.2.6 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-function-definitions-runtime-semantics-evaluation Completion FunctionExpression::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; // 1. Return InstantiateOrdinaryFunctionExpression of FunctionExpression. return instantiate_ordinary_function_expression(interpreter, name()); } // 15.2.5 Runtime Semantics: InstantiateOrdinaryFunctionExpression, https://tc39.es/ecma262/#sec-runtime-semantics-instantiateordinaryfunctionexpression Value FunctionExpression::instantiate_ordinary_function_expression(Interpreter& interpreter, FlyString given_name) const { auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); 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* environment = interpreter.lexical_environment(); if (has_own_name) { VERIFY(environment); environment = new_declarative_environment(*environment); MUST(environment->create_immutable_binding(vm, name(), false)); } auto* private_environment = vm.running_execution_context().private_environment; auto closure = ECMAScriptFunctionObject::create(realm, used_name, source_text(), body(), parameters(), function_length(), environment, private_environment, 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(environment->initialize_binding(vm, name(), closure)); return closure; } // 14.4.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-empty-statement-runtime-semantics-evaluation Completion EmptyStatement::execute(Interpreter&) const { // 1. Return empty. return Optional {}; } // 14.5.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-expression-statement-runtime-semantics-evaluation Completion ExpressionStatement::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; // 1. Let exprRef be the result of evaluating Expression. // 2. Return ? GetValue(exprRef). return m_expression->execute(interpreter); } // TODO: This shouldn't exist. Refactor into EvaluateCall. ThrowCompletionOr CallExpression::compute_this_and_callee(Interpreter& interpreter, Reference const& callee_reference) const { auto& vm = interpreter.vm(); if (callee_reference.is_property_reference()) { auto this_value = callee_reference.get_this_value(); auto callee = TRY(callee_reference.get_value(vm)); return ThisAndCallee { this_value, callee }; } Value this_value = js_undefined(); if (callee_reference.is_environment_reference()) { if (Object* base_object = callee_reference.base_environment().with_base_object(); base_object != nullptr) this_value = base_object; } // [[Call]] will handle that in non-strict mode the this value becomes the global object return ThisAndCallee { this_value, callee_reference.is_unresolvable() ? TRY(m_callee->execute(interpreter)).release_value() : TRY(callee_reference.get_value(vm)) }; } // 13.3.8.1 Runtime Semantics: ArgumentListEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-argumentlistevaluation static ThrowCompletionOr argument_list_evaluation(Interpreter& interpreter, Vector const& arguments, MarkedVector& list) { auto& vm = interpreter.vm(); list.ensure_capacity(arguments.size()); for (auto& argument : arguments) { auto value = TRY(argument.value->execute(interpreter)).release_value(); if (argument.is_spread) { TRY(get_iterator_values(vm, value, [&](Value iterator_value) -> Optional { 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) 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)).release_value(); // 3. If arguments is empty, let argList be a new empty List. // 4. Else, // a. Let argList be ? ArgumentListEvaluation of arguments. MarkedVector arg_list(vm.heap()); TRY(argument_list_evaluation(interpreter, 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, constructor, "constructor"sv); // 6. Return ? Construct(constructor, argList). return Value { TRY(construct(vm, constructor.as_function(), move(arg_list))) }; } Completion CallExpression::throw_type_error_for_callee(Interpreter& interpreter, Value callee_value, StringView call_type) const { auto& vm = interpreter.vm(); if (is(*m_callee) || is(*m_callee)) { String expression_string; if (is(*m_callee)) { expression_string = static_cast(*m_callee).string(); } else { expression_string = static_cast(*m_callee).to_string_approximation(); } return vm.throw_completion(ErrorType::IsNotAEvaluatedFrom, callee_value.to_string_without_side_effects(), call_type, expression_string); } else { return vm.throw_completion(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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto callee_reference = TRY(m_callee->to_reference(interpreter)); auto [this_value, callee] = TRY(compute_this_and_callee(interpreter, callee_reference)); VERIFY(!callee.is_empty()); MarkedVector arg_list(vm.heap()); TRY(argument_list_evaluation(interpreter, m_arguments, arg_list)); if (!callee.is_function()) return throw_type_error_for_callee(interpreter, 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(vm, script_value, vm.in_strict_mode() ? CallerMode::Strict : CallerMode::NonStrict, EvalMode::Direct); } return call(vm, 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) 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 arg_list(vm.heap()); if (m_is_synthetic == IsPartOfSyntheticConstructor::Yes) { // NOTE: This is the case where we have a fake constructor(...args) { super(...args); } which // shouldn't call @@iterator of %Array.prototype%. VERIFY(m_arguments.size() == 1); VERIFY(m_arguments[0].is_spread); auto const& argument = m_arguments[0]; auto value = MUST(argument.value->execute(interpreter)).release_value(); VERIFY(value.is_object() && is(value.as_object())); auto& array_value = static_cast(value.as_object()); auto length = MUST(length_of_array_like(vm, array_value)); for (size_t i = 0; i < length; ++i) arg_list.append(array_value.get_without_side_effects(PropertyKey { i })); } else { TRY(argument_list_evaluation(interpreter, m_arguments, arg_list)); } // 5. If IsConstructor(func) is false, throw a TypeError exception. if (!func || !Value(func).is_constructor()) return vm.throw_completion(ErrorType::NotAConstructor, "Super constructor"); // 6. Let result be ? Construct(func, argList, newTarget). auto* result = TRY(construct(vm, static_cast(*func), move(arg_list), &new_target.as_function())); // 7. Let thisER be GetThisEnvironment(). auto& this_er = verify_cast(get_this_environment(vm)); // 8. Perform ? thisER.BindThisValue(result). TRY(this_er.bind_this_value(vm, 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&) 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); // 1. Let exprRef be the result of evaluating UnaryExpression. // 2. Let value be ? GetValue(exprRef). auto value = TRY(m_argument->execute(interpreter)).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) const { InterpreterNodeScope node_scope { interpreter, *this }; // ReturnStatement : return ; if (!m_argument) { // 1. Return Completion Record { [[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)); // NOTE: Generators are not supported in the AST interpreter // 3. If GetGeneratorKind() is async, set exprValue to ? Await(exprValue). // 4. Return Completion Record { [[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) 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)).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 ? UpdateEmpty(stmtCompletion, undefined). return m_consequent->execute(interpreter).update_empty(js_undefined()); } // 4. Else, if (m_alternate) { // a. Let stmtCompletion be the result of evaluating the second Statement. // 5. Return ? UpdateEmpty(stmtCompletion, undefined). return m_alternate->execute(interpreter).update_empty(js_undefined()); } // IfStatement : if ( Expression ) Statement // 3. If exprValue is false, then // a. Return undefined. return 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = global_object.vm(); // 1. Let value be the result of evaluating Expression. auto value = TRY(m_object->execute(interpreter)).release_value(); // 2. Let obj be ? ToObject(? GetValue(value)). auto* object = TRY(value.to_object(vm)); // 3. Let oldEnv be the running execution context's LexicalEnvironment. auto* old_environment = 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. vm.running_execution_context().lexical_environment = new_environment; // 6. Let C be the result of evaluating Statement. auto result = m_body->execute(interpreter); // 7. Set the running execution context's LexicalEnvironment to oldEnv. vm.running_execution_context().lexical_environment = old_environment; // 8. Return ? 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 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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *this, {}); } // 14.7.3.2 Runtime Semantics: WhileLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-whileloopevaluation Completion WhileStatement::loop_evaluation(Interpreter& interpreter, Vector 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)).release_value(); // c. If ToBoolean(exprValue) is false, return V. if (!test_result.to_boolean()) return last_value; // d. Let stmtResult be the result of evaluating Statement. auto body_result = m_body->execute(interpreter); // e. If LoopContinues(stmtResult, labelSet) is false, return ? 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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *this, {}); } // 14.7.2.2 Runtime Semantics: DoWhileLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-dowhileloopevaluation Completion DoWhileStatement::loop_evaluation(Interpreter& interpreter, Vector 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); // b. If LoopContinues(stmtResult, labelSet) is false, return ? 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)).release_value(); // f. If ToBoolean(exprValue) is false, return V. if (!test_result.to_boolean()) return 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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *this, {}); } // 14.7.4.2 Runtime Semantics: ForLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forloopevaluation Completion ForStatement::loop_evaluation(Interpreter& interpreter, Vector const& label_set) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); // 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(*m_init) && static_cast(*m_init).declaration_kind() != DeclarationKind::Var) { auto* loop_environment = new_declarative_environment(*old_environment); auto& declaration = static_cast(*m_init); declaration.for_each_bound_name([&](auto const& name) { if (declaration.declaration_kind() == DeclarationKind::Const) { MUST(loop_environment->create_immutable_binding(vm, name, true)); } else { MUST(loop_environment->create_mutable_binding(vm, name, false)); ++per_iteration_bindings_size; } }); interpreter.vm().running_execution_context().lexical_environment = loop_environment; } (void)TRY(m_init->execute(interpreter)); } // 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(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 unused. }; // 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)).release_value(); // iii. If ToBoolean(testValue) is false, return V. if (!test_value.to_boolean()) return last_value; } // b. Let result be the result of evaluating stmt. auto result = m_body->execute(interpreter); // c. If LoopContinues(result, labelSet) is false, return ? 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)); } } VERIFY_NOT_REACHED(); } struct ForInOfHeadState { explicit ForInOfHeadState(Variant, NonnullRefPtr> lhs) { lhs.visit( [&](NonnullRefPtr& ast_node) { expression_lhs = ast_node.ptr(); }, [&](NonnullRefPtr& 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 execute_head(Interpreter& interpreter, Value next_value) const { VERIFY(!next_value.is_empty()); auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); Optional 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(*expression_lhs)) { auto& declaration = static_cast(*expression_lhs); VERIFY(declaration.declarations().first().target().has>()); lhs_reference = TRY(declaration.declarations().first().target().get>()->to_reference(interpreter)); } else { VERIFY(is(*expression_lhs) || is(*expression_lhs) || is(*expression_lhs)); auto& expression = static_cast(*expression_lhs); lhs_reference = TRY(expression.to_reference(interpreter)); } } } // h. Else, else { VERIFY(expression_lhs && is(*expression_lhs)); iteration_environment = new_declarative_environment(*interpreter.lexical_environment()); auto& for_declaration = static_cast(*expression_lhs); for_declaration.for_each_bound_name([&](auto const& name) { if (for_declaration.declaration_kind() == DeclarationKind::Const) MUST(iteration_environment->create_immutable_binding(vm, name, false)); else MUST(iteration_environment->create_mutable_binding(vm, name, true)); }); interpreter.vm().running_execution_context().lexical_environment = iteration_environment; if (!destructuring) { VERIFY(for_declaration.declarations().first().target().has>()); lhs_reference = MUST(interpreter.vm().resolve_binding(for_declaration.declarations().first().target().get>()->string())); } } // i. If destructuring is false, then if (!destructuring) { VERIFY(lhs_reference.has_value()); if (lhs_kind == LexicalBinding) return lhs_reference->initialize_referenced_binding(vm, next_value); else return lhs_reference->put_value(vm, 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(*expression_lhs)); auto& for_declaration = static_cast(*expression_lhs); auto& binding_pattern = for_declaration.declarations().first().target().get>(); 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 for_in_of_head_execute(Interpreter& interpreter, Variant, NonnullRefPtr> lhs, Expression const& rhs) { auto& vm = interpreter.vm(); ForInOfHeadState state(lhs); if (auto* ast_ptr = lhs.get_pointer>(); ast_ptr && is(*(*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(*(*ast_ptr)); VERIFY(variable_declaration.declarations().size() == 1); state.destructuring = variable_declaration.declarations().first().target().has>(); 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>()); auto& binding_id = variable.target().get>()->string(); auto reference = TRY(interpreter.vm().resolve_binding(binding_id)); auto result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(*variable.init(), binding_id)); TRY(reference.put_value(vm, 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(vm, name, false)); }); } if (new_environment) { // 2.d Set the running execution context's LexicalEnvironment to newEnv. TemporaryChange 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)).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)).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)).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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *this, {}); } // 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation Completion ForInStatement::loop_evaluation(Interpreter& interpreter, Vector const& label_set) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); auto for_in_head_state = TRY(for_in_of_head_execute(interpreter, 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 Record { [[Type]]: break, [[Value]]: empty, [[Target]]: empty }. return { Completion::Type::Break, {}, {} }; } // b. Let obj be ! ToObject(exprValue). auto* object = MUST(rhs_result.to_object(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 // 2. Let oldEnv be the running execution context's LexicalEnvironment. Environment* old_environment = interpreter.lexical_environment(); auto restore_scope = ScopeGuard([&] { 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 { TRY(for_in_head_state.execute_head(interpreter, value)); // l. Let result be the result of evaluating stmt. auto result = m_body->execute(interpreter); // m. Set the running execution context's LexicalEnvironment to oldEnv. vm.running_execution_context().lexical_environment = old_environment; // n. If LoopContinues(result, labelSet) is false, then if (!loop_continues(result, label_set)) { // 1. Return 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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *this, {}); } // 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation Completion ForOfStatement::loop_evaluation(Interpreter& interpreter, Vector const& label_set) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); auto for_of_head_state = TRY(for_in_of_head_execute(interpreter, 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([&] { vm.running_execution_context().lexical_environment = old_environment; }); // 3. Let V be undefined. auto last_value = js_undefined(); Optional status; (void)TRY(get_iterator_values(vm, rhs_result, [&](Value value) -> Optional { TRY(for_of_head_state.execute_head(interpreter, value)); // l. Let result be the result of evaluating stmt. auto result = m_body->execute(interpreter); // m. Set the running execution context's LexicalEnvironment to oldEnv. 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 V. return status.value_or(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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *this, {}); } // 14.7.5.5 Runtime Semantics: ForInOfLoopEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-forinofloopevaluation Completion ForAwaitOfStatement::loop_evaluation(Interpreter& interpreter, Vector const& label_set) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); // 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, 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(vm, rhs_result, IteratorHint::Async)); // 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([&] { 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(vm, 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(ErrorType::IterableNextBadReturn); // d. Let done be ? IteratorComplete(nextResult). auto done = TRY(iterator_complete(vm, next_result.as_object())); // e. If done is true, return V. if (done) return last_value; // f. Let nextValue be ? IteratorValue(nextResult). auto next_value = TRY(iterator_value(vm, next_result.as_object())); // NOTE: This performs steps g. through to k. TRY(for_of_head_state.execute_head(interpreter, next_value)); // l. Let result be the result of evaluating stmt. auto result = m_body->execute(interpreter); // 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(vm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); // 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(*m_lhs)) { auto& private_identifier = static_cast(*m_lhs).string(); auto rhs_result = TRY(m_rhs->execute(interpreter)).release_value(); if (!rhs_result.is_object()) return interpreter.vm().throw_completion(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)).release_value(); auto rhs_result = TRY(m_rhs->execute(interpreter)).release_value(); switch (m_op) { case BinaryOp::Addition: return TRY(add(vm, lhs_result, rhs_result)); case BinaryOp::Subtraction: return TRY(sub(vm, lhs_result, rhs_result)); case BinaryOp::Multiplication: return TRY(mul(vm, lhs_result, rhs_result)); case BinaryOp::Division: return TRY(div(vm, lhs_result, rhs_result)); case BinaryOp::Modulo: return TRY(mod(vm, lhs_result, rhs_result)); case BinaryOp::Exponentiation: return TRY(exp(vm, 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(vm, lhs_result, rhs_result))); case BinaryOp::LooselyInequals: return Value(!TRY(is_loosely_equal(vm, lhs_result, rhs_result))); case BinaryOp::GreaterThan: return TRY(greater_than(vm, lhs_result, rhs_result)); case BinaryOp::GreaterThanEquals: return TRY(greater_than_equals(vm, lhs_result, rhs_result)); case BinaryOp::LessThan: return TRY(less_than(vm, lhs_result, rhs_result)); case BinaryOp::LessThanEquals: return TRY(less_than_equals(vm, lhs_result, rhs_result)); case BinaryOp::BitwiseAnd: return TRY(bitwise_and(vm, lhs_result, rhs_result)); case BinaryOp::BitwiseOr: return TRY(bitwise_or(vm, lhs_result, rhs_result)); case BinaryOp::BitwiseXor: return TRY(bitwise_xor(vm, lhs_result, rhs_result)); case BinaryOp::LeftShift: return TRY(left_shift(vm, lhs_result, rhs_result)); case BinaryOp::RightShift: return TRY(right_shift(vm, lhs_result, rhs_result)); case BinaryOp::UnsignedRightShift: return TRY(unsigned_right_shift(vm, lhs_result, rhs_result)); case BinaryOp::In: return TRY(in(vm, lhs_result, rhs_result)); case BinaryOp::InstanceOf: return TRY(instance_of(vm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; // 1. Let lref be the result of evaluating . // 2. Let lval be ? GetValue(lref). auto lhs_result = TRY(m_lhs->execute(interpreter)).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); // 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); // 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); } // 4. Otherwise, return lval. return lhs_result; } VERIFY_NOT_REACHED(); } ThrowCompletionOr Expression::to_reference(Interpreter&) const { return Reference {}; } ThrowCompletionOr Identifier::to_reference(Interpreter& interpreter) 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 MemberExpression::to_reference(Interpreter& interpreter) const { auto& vm = interpreter.vm(); // 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(object())) { // 1. Let env be GetThisEnvironment(). auto& environment = get_this_environment(vm); // 2. Let actualThis be ? env.GetThisBinding(). auto actual_this = TRY(environment.get_this_binding(vm)); 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)).release_value(); // 5. Let propertyKey be ? ToPropertyKey(propertyNameValue). property_key = TRY(property_name_value.to_property_key(vm)); } else { // SuperProperty : super . IdentifierName // 3. Let propertyKey be StringValue of IdentifierName. VERIFY(is(property())); property_key = static_cast(property()).string(); } // 6. If the source text 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(vm, actual_this, property_key, strict)); } auto base_reference = TRY(m_object->to_reference(interpreter)); Value base_value; if (base_reference.is_valid_reference()) base_value = TRY(base_reference.get_value(vm)); else base_value = TRY(m_object->execute(interpreter)).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)).release_value(); VERIFY(!value.is_empty()); TRY(require_object_coercible(vm, base_value)); property_key = TRY(PropertyKey::from_value(vm, value)); } else if (is(*m_property)) { auto& private_identifier = static_cast(*m_property); return make_private_reference(interpreter.vm(), base_value, private_identifier.string()); } else { property_key = verify_cast(*m_property).string(); TRY(require_object_coercible(vm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); if (m_op == UnaryOp::Delete) { auto reference = TRY(m_lhs->to_reference(interpreter)); return Value(TRY(reference.delete_(vm))); } Value lhs_result; if (m_op == UnaryOp::Typeof && is(*m_lhs)) { auto reference = TRY(m_lhs->to_reference(interpreter)); if (reference.is_unresolvable()) lhs_result = js_undefined(); else lhs_result = TRY(reference.get_value(vm)); VERIFY(!lhs_result.is_empty()); } else { // 1. Let expr be the result of evaluating UnaryExpression. lhs_result = TRY(m_lhs->execute(interpreter)).release_value(); } switch (m_op) { case UnaryOp::BitwiseNot: return TRY(bitwise_not(vm, lhs_result)); case UnaryOp::Not: return Value(!lhs_result.to_boolean()); case UnaryOp::Plus: return TRY(unary_plus(vm, lhs_result)); case UnaryOp::Minus: return TRY(unary_minus(vm, 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&) const { // The semantics for SuperExpression are handled in CallExpression and SuperCall. VERIFY_NOT_REACHED(); } Completion ClassElement::execute(Interpreter&) const { // Note: The semantics of class element are handled in class_element_evaluation VERIFY_NOT_REACHED(); } static ThrowCompletionOr class_key_to_property_name(Interpreter& interpreter, Expression const& key) { auto& vm = interpreter.vm(); if (is(key)) { auto& private_identifier = static_cast(key); auto* private_environment = interpreter.vm().running_execution_context().private_environment; VERIFY(private_environment); return ClassElementName { private_environment->resolve_private_identifier(private_identifier.string()) }; } auto prop_key = TRY(key.execute(interpreter)).release_value(); if (prop_key.is_object()) prop_key = TRY(prop_key.to_primitive(vm, Value::PreferredType::String)); auto property_key = TRY(PropertyKey::from_value(vm, prop_key)); return ClassElementName { property_key }; } // 15.4.5 Runtime Semantics: MethodDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-methoddefinitionevaluation ThrowCompletionOr ClassMethod::class_element_evaluation(Interpreter& interpreter, Object& target) const { auto property_key_or_private_name = TRY(class_key_to_property_name(interpreter, *m_key)); auto method_value = TRY(m_function->execute(interpreter)).release_value(); auto function_handle = make_handle(&method_value.as_function()); auto& method_function = static_cast(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()) { auto& property_key = property_key_or_private_name.get(); 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(); 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, FlyString field_name) : Statement(source_range) , m_expression(move(expression)) , m_class_field_identifier_name(move(field_name)) { } Completion execute(Interpreter& interpreter) 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(m_expression, m_class_field_identifier_name)); // 5. Return Completion Record { [[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 m_expression; FlyString m_class_field_identifier_name; // [[ClassFieldIdentifierName]] }; // 15.7.10 Runtime Semantics: ClassFieldDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-classfielddefinitionevaluation ThrowCompletionOr ClassField::class_element_evaluation(Interpreter& interpreter, Object& target) const { auto& global_object = interpreter.global_object(); auto& realm = *global_object.associated_realm(); auto property_key_or_private_name = TRY(class_key_to_property_name(interpreter, *m_key)); Handle 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(m_initializer->source_range(), copy_initializer.release_nonnull(), name); initializer = make_handle(ECMAScriptFunctionObject::create(realm, 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 nullopt_or_private_identifier_description(Expression const& expression) { if (is(expression)) return static_cast(expression).string(); return {}; } Optional ClassField::private_bound_identifier() const { return nullopt_or_private_identifier_description(*m_key); } Optional 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 StaticInitializer::class_element_evaluation(Interpreter& interpreter, Object& home_object) const { auto& global_object = interpreter.global_object(); auto& realm = *global_object.associated_realm(); // 1. Let lex be the running execution context's LexicalEnvironment. auto* lexical_environment = interpreter.vm().running_execution_context().lexical_environment; // 2. Let privateEnv be the running execution context's PrivateEnvironment. auto* private_environment = 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, privateEnv). // Note: The function bodyFunction is never directly accessible to ECMAScript code. auto* body_function = ECMAScriptFunctionObject::create(realm, String::empty(), String::empty(), *m_function_body, {}, 0, lexical_environment, private_environment, 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) 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, 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 binding_class_declaration_evaluation(Interpreter& interpreter, ClassExpression const& class_expression) { auto& vm = interpreter.vm(); // 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, {}, "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, 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(vm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; // 1. Perform ? BindingClassDeclarationEvaluation of this ClassDeclaration. (void)TRY(binding_class_declaration_evaluation(interpreter, m_class_expression)); // 2. Return empty. return Optional {}; } // 15.7.14 Runtime Semantics: ClassDefinitionEvaluation, https://tc39.es/ecma262/#sec-runtime-semantics-classdefinitionevaluation ThrowCompletionOr ClassExpression::class_definition_evaluation(Interpreter& interpreter, FlyString const& binding_name, FlyString const& class_name) const { auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); auto* environment = vm.lexical_environment(); VERIFY(environment); auto* class_environment = 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_environment->create_immutable_binding(vm, 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_environment; // 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)); if (reference.is_valid_reference()) { super_class = TRY(reference.get_value(vm)); } else { super_class = TRY(m_super_class->execute(interpreter)).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(ErrorType::ClassExtendsValueNotAConstructorOrNull, super_class.to_string_without_side_effects()); } else { auto super_class_prototype = TRY(super_class.get(vm, vm.names.prototype)); if (!super_class_prototype.is_null() && !super_class_prototype.is_object()) return vm.throw_completion(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(realm, proto_parent); VERIFY(prototype); vm.running_execution_context().lexical_environment = class_environment; 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. By using a synthetic super(...args) which does not call @@iterator of %Array.prototype% auto class_constructor_value = TRY(m_constructor->execute(interpreter)).release_value(); update_function_name(class_constructor_value, class_name); VERIFY(class_constructor_value.is_function() && is(class_constructor_value.as_function())); auto* class_constructor = static_cast(&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>; Vector static_private_methods; Vector instance_private_methods; Vector instance_fields; Vector 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, element.is_static() ? *class_constructor : *prototype)); if (element_value.has()) { auto& container = element.is_static() ? static_private_methods : instance_private_methods; auto& private_element = element_value.get(); 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())); } else if (auto* class_field_definition_ptr = element_value.get_pointer()) { 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() && element_value.get().value().has_value()); auto& element_object = element_value.get().value()->as_object(); VERIFY(is(element_object)); static_elements.append(make_handle(static_cast(&element_object))); } } vm.running_execution_context().lexical_environment = environment; restore_environment.disarm(); if (!binding_name.is_null()) MUST(class_environment->initialize_binding(vm, binding_name, class_constructor)); for (auto& field : instance_fields) class_constructor->add_field(field); 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( [&](ClassFieldDefinition& field) -> ThrowCompletionOr { return TRY(class_constructor->define_field(field)); }, [&](Handle static_block_function) -> ThrowCompletionOr { VERIFY(!static_block_function.is_null()); // We discard any value returned here. TRY(call(vm, *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(*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 ClassDeclaration::for_each_bound_name(ThrowCompletionOrVoidCallback&& 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>(); binding_ptr && (*binding_ptr)->contains_expression()) return true; } return false; } ThrowCompletionOr BindingPattern::for_each_bound_name(ThrowCompletionOrVoidCallback&& callback) const { for (auto const& entry : entries) { auto const& alias = entry.alias; if (alias.has>()) { TRY(callback(alias.get>()->string())); } else if (alias.has>()) { TRY(alias.get>()->for_each_bound_name(forward(callback))); } else { auto const& name = entry.name; if (name.has>()) TRY(callback(name.get>()->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>()) { entry.name.get>()->dump(indent + 3); } else { entry.name.get>()->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>()) { entry.alias.get>()->dump(indent + 3); } else if (entry.alias.has>()) { entry.alias.get>()->dump(indent + 3); } else if (entry.alias.has>()) { entry.alias.get>()->dump(indent + 3); } else { print_indent(indent + 3); outln(""); } 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 FunctionDeclaration::for_each_bound_name(ThrowCompletionOrVoidCallback&& 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); // 1. Return ? ResolveBinding(StringValue of Identifier). auto reference = TRY(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(vm)); } void Identifier::dump(int indent) const { print_indent(indent); outln("Identifier \"{}\"", m_string); } Completion PrivateIdentifier::execute(Interpreter&) 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) const { InterpreterNodeScope node_scope { interpreter, *this }; return m_target->execute(interpreter); } // 13.2.1.1 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-this-keyword-runtime-semantics-evaluation Completion ThisExpression::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); // 1. Return ? ResolveThisBinding(). return vm.resolve_this_binding(); } 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); if (m_op == AssignmentOp::Assignment) { // AssignmentExpression : LeftHandSideExpression = AssignmentExpression return m_lhs.visit( // 1. If LeftHandSideExpression is neither an ObjectLiteral nor an ArrayLiteral, then [&](NonnullRefPtr const& lhs) -> ThrowCompletionOr { // a. Let lref be the result of evaluating LeftHandSideExpression. // b. ReturnIfAbrupt(lref). auto reference = TRY(lhs->to_reference(interpreter)); 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(*lhs).string(); rhs_result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(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)).release_value(); } // e. Perform ? PutValue(lref, rval). TRY(reference.put_value(vm, rhs_result)); // f. Return rval. return rhs_result; }, // 2. Let assignmentPattern be the AssignmentPattern that is covered by LeftHandSideExpression. [&](NonnullRefPtr const& pattern) -> ThrowCompletionOr { // 3. Let rref be the result of evaluating AssignmentExpression. // 4. Let rval be ? GetValue(rref). auto rhs_result = TRY(m_rhs->execute(interpreter)).release_value(); // 5. Perform ? DestructuringAssignmentEvaluation of assignmentPattern with argument rval. TRY(interpreter.vm().destructuring_assignment_evaluation(pattern, rhs_result, global_object)); // 6. Return rval. return rhs_result; }); } VERIFY(m_lhs.has>()); // 1. Let lref be the result of evaluating LeftHandSideExpression. auto& lhs_expression = *m_lhs.get>(); auto reference = TRY(lhs_expression.to_reference(interpreter)); // 2. Let lval be ? GetValue(lref). auto lhs_result = TRY(reference.get_value(vm)); // 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(lhs_expression).string(); rhs_result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(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)).release_value(); } // 7. Perform ? PutValue(lref, rval). TRY(reference.put_value(vm, 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)).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(vm, lhs_result, rhs_result)); break; case AssignmentOp::SubtractionAssignment: rhs_result = TRY(sub(vm, lhs_result, rhs_result)); break; case AssignmentOp::MultiplicationAssignment: rhs_result = TRY(mul(vm, lhs_result, rhs_result)); break; case AssignmentOp::DivisionAssignment: rhs_result = TRY(div(vm, lhs_result, rhs_result)); break; case AssignmentOp::ModuloAssignment: rhs_result = TRY(mod(vm, lhs_result, rhs_result)); break; case AssignmentOp::ExponentiationAssignment: rhs_result = TRY(exp(vm, lhs_result, rhs_result)); break; case AssignmentOp::BitwiseAndAssignment: rhs_result = TRY(bitwise_and(vm, lhs_result, rhs_result)); break; case AssignmentOp::BitwiseOrAssignment: rhs_result = TRY(bitwise_or(vm, lhs_result, rhs_result)); break; case AssignmentOp::BitwiseXorAssignment: rhs_result = TRY(bitwise_xor(vm, lhs_result, rhs_result)); break; case AssignmentOp::LeftShiftAssignment: rhs_result = TRY(left_shift(vm, lhs_result, rhs_result)); break; case AssignmentOp::RightShiftAssignment: rhs_result = TRY(right_shift(vm, lhs_result, rhs_result)); break; case AssignmentOp::UnsignedRightShiftAssignment: rhs_result = TRY(unsigned_right_shift(vm, 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(vm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); // 1. Let expr be the result of evaluating . auto reference = TRY(m_argument->to_reference(interpreter)); // 2. Let oldValue be ? ToNumeric(? GetValue(expr)). auto old_value = TRY(reference.get_value(vm)); old_value = TRY(old_value.to_numeric(vm)); 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(vm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); for (auto& declarator : m_declarations) { if (auto* init = declarator.init()) { TRY(declarator.target().visit( [&](NonnullRefPtr const& id) -> ThrowCompletionOr { auto reference = TRY(id->to_reference(interpreter)); auto initializer_result = TRY(interpreter.vm().named_evaluation_if_anonymous_function(*init, id->string())); VERIFY(!initializer_result.is_empty()); if (m_declaration_kind == DeclarationKind::Var) return reference.put_value(vm, initializer_result); else return reference.initialize_referenced_binding(vm, initializer_result); }, [&](NonnullRefPtr const& pattern) -> ThrowCompletionOr { auto initializer_result = TRY(init->execute(interpreter)).release_value(); Environment* environment = m_declaration_kind == DeclarationKind::Var ? nullptr : interpreter.lexical_environment(); return vm.binding_initialization(pattern, initializer_result, environment, global_object); })); } else if (m_declaration_kind != DeclarationKind::Var) { VERIFY(declarator.target().has>()); auto& identifier = declarator.target().get>(); auto reference = TRY(identifier->to_reference(interpreter)); TRY(reference.initialize_referenced_binding(vm, js_undefined())); } } return normal_completion({}); } Completion VariableDeclarator::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; // NOTE: VariableDeclarator execution is handled by VariableDeclaration. VERIFY_NOT_REACHED(); } ThrowCompletionOr VariableDeclaration::for_each_bound_name(ThrowCompletionOrVoidCallback&& callback) const { for (auto const& entry : declarations()) { TRY(entry.target().visit( [&](NonnullRefPtr const& id) { return callback(id->string()); }, [&](NonnullRefPtr 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) 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); // 1. Let obj be OrdinaryObjectCreate(%Object.prototype%). auto* object = Object::create(realm, global_object.object_prototype()); // 2. Perform ? PropertyDefinitionEvaluation of PropertyDefinitionList with argument obj. for (auto& property : m_properties) { auto key = TRY(property.key().execute(interpreter)).release_value(); // PropertyDefinition : ... AssignmentExpression if (property.type() == ObjectProperty::Type::Spread) { // 4. Perform ? CopyDataProperties(object, fromValue, excludedNames). TRY(object->copy_data_properties(vm, key, {})); // 5. Return unused. continue; } auto value = TRY(property.value().execute(interpreter)).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(value.as_function()).set_home_object(object); auto property_key = TRY(PropertyKey::from_value(vm, 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 = ""; if (is(*m_object)) object_string = static_cast(*m_object).string(); if (is_computed()) return String::formatted("{}[]", object_string); return String::formatted("{}.{}", object_string, verify_cast(*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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); auto reference = TRY(to_reference(interpreter)); return TRY(reference.get_value(vm)); } bool MemberExpression::ends_in_private_name() const { if (is_computed()) return false; if (is(*m_property)) return true; if (is(*m_property)) return static_cast(*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::to_reference_and_value(Interpreter& interpreter) const { auto& vm = interpreter.vm(); auto base_reference = TRY(m_base->to_reference(interpreter)); auto base = base_reference.is_unresolvable() ? TRY(m_base->execute(interpreter)).release_value() : TRY(base_reference.get_value(vm)); 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 { return create_ast_node(source_range(), create_ast_node(source_range(), base_reference, base), call.arguments); }, [&](ComputedReference const& ref) -> NonnullRefPtr { return create_ast_node(source_range(), create_ast_node(source_range(), base_reference, base), ref.expression, true); }, [&](MemberReference const& ref) -> NonnullRefPtr { return create_ast_node(source_range(), create_ast_node(source_range(), base_reference, base), ref.identifier, false); }, [&](PrivateMemberReference const& ref) -> NonnullRefPtr { return create_ast_node(source_range(), create_ast_node(source_range(), base_reference, base), ref.private_identifier, false); }); if (is(*expression)) { base_reference = JS::Reference {}; base = TRY(expression->execute(interpreter)).release_value(); } else { base_reference = TRY(expression->to_reference(interpreter)); base = TRY(base_reference.get_value(vm)); } } 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) const { InterpreterNodeScope node_scope { interpreter, *this }; return TRY(to_reference_and_value(interpreter)).value; } ThrowCompletionOr OptionalChain::to_reference(Interpreter& interpreter) const { return TRY(to_reference_and_value(interpreter)).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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& realm = *global_object.associated_realm(); // 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>()); VERIFY(script_or_module.get>()); VERIFY(is(*script_or_module.get>())); auto& module = static_cast(*script_or_module.get>()); // 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(realm, 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); // 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 = 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)); 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)).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(vm, global_object.promise_constructor())); // 7. Let specifierString be Completion(ToString(specifier)). // 8. IfAbruptRejectPromise(specifierString, promiseCapability). auto specifier_string = TRY_OR_REJECT_WITH_VALUE(vm, promise_capability, specifier->to_string(vm)); // 9. Let assertions be a new empty List. Vector 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(realm, String::formatted(ErrorType::NotAnObject.message(), "ImportOptions")); // i. Perform ! Call(promiseCapability.[[Reject]], undefined, « a newly created TypeError object »). MUST(call(vm, *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(vm, promise_capability, options_value.get(vm, 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(realm, String::formatted(ErrorType::NotAnObject.message(), "ImportOptionsAssertions")); // 1. Perform ! Call(promiseCapability.[[Reject]], undefined, « a newly created TypeError object »). MUST(call(vm, *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(vm, promise_capability, assertion_object.as_object().enumerable_own_property_names(Object::PropertyKind::Key)); // iv. Let supportedAssertions be ! HostGetSupportedImportAssertions(). auto supported_assertions = 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(vm)); // 1. Let value be Get(assertionsObj, key). // 2. IfAbruptRejectPromise(value, promiseCapability). auto value = TRY_OR_REJECT_WITH_VALUE(vm, promise_capability, assertion_object.get(vm, property_key)); // 3. If Type(value) is not String, then if (!value.is_string()) { auto* error = TypeError::create(realm, String::formatted(ErrorType::NotAString.message(), "Import Assertion option value")); // a. Perform ! Call(promiseCapability.[[Reject]], undefined, « a newly created TypeError object »). MUST(call(vm, *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) 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) 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) 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) 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) 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& realm = *global_object.associated_realm(); // 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 regex(parsed_regex(), parsed_pattern(), parsed_flags()); return Value { RegExpObject::create(realm, 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(""); } } } // 13.2.4.2 Runtime Semantics: Evaluation, https://tc39.es/ecma262/#sec-array-initializer-runtime-semantics-evaluation Completion ArrayExpression::execute(Interpreter& interpreter) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); // 1. Let array be ! ArrayCreate(0). auto* array = MUST(Array::create(realm, 0)); // 2. Perform ? ArrayAccumulation of ElementList with arguments array and 0. array->indexed_properties(); size_t index = 0; for (auto& element : m_elements) { auto value = Value(); if (element) { value = TRY(element->execute(interpreter)).release_value(); if (is(*element)) { (void)TRY(get_iterator_values(vm, value, [&](Value iterator_value) -> Optional { array->indexed_properties().put(index++, iterator_value, default_attributes); return {}; })); continue; } } array->indexed_properties().put(index++, value, default_attributes); } // 3. 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); 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)).release_value(); // 4. Let middle be ? ToString(sub). auto string = TRY(sub.to_string(vm)); 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); // NOTE: This is both // MemberExpression : MemberExpression TemplateLiteral // CallExpression : CallExpression TemplateLiteral // As the only difference is the first step. // 1. Let tagRef be ? Evaluation of MemberExpression. // 1. Let tagRef be ? Evaluation of CallExpression. // 2. Let tagFunc be ? GetValue(tagRef). auto tag = TRY(m_tag->execute(interpreter)).release_value(); // 3. Let thisCall be this CallExpression. // 3. Let thisCall be this MemberExpression. // FIXME: 4. Let tailCall be IsInTailPosition(thisCall). // NOTE: A tagged template is a function call where the arguments of the call are derived from a // TemplateLiteral (13.2.8). The actual arguments include a template object (13.2.8.3) // and the values produced by evaluating the expressions embedded within the TemplateLiteral. auto template_ = TRY(get_template_object(interpreter)); MarkedVector arguments(interpreter.vm().heap()); arguments.append(template_); auto& expressions = m_template_literal->expressions(); // tag`${foo}` -> "", foo, "" -> tag(["", ""], foo) // tag`foo${bar}baz${qux}` -> "foo", bar, "baz", qux, "" -> tag(["foo", "baz", ""], bar, qux) // So we want all the odd expressions for (size_t i = 1; i < expressions.size(); i += 2) arguments.append(TRY(expressions[i].execute(interpreter)).release_value()); // 5. Return ? EvaluateCall(tagFunc, tagRef, TemplateLiteral, tailCall). return call(vm, tag, js_undefined(), move(arguments)); } // 13.2.8.3 GetTemplateObject ( templateLiteral ), https://tc39.es/ecma262/#sec-gettemplateobject ThrowCompletionOr TaggedTemplateLiteral::get_template_object(Interpreter& interpreter) const { // 1. Let realm be the current Realm Record. auto& global_object = interpreter.global_object(); auto& realm = *global_object.associated_realm(); // 2. Let templateRegistry be realm.[[TemplateMap]]. // 3. For each element e of templateRegistry, do // a. If e.[[Site]] is the same Parse Node as templateLiteral, then // i. Return e.[[Array]]. // NOTE: Instead of caching on the realm we cache on the Parse Node side as // this makes it easier to track whether it is the same parse node. if (auto cached_value_or_end = m_cached_values.find(&realm); cached_value_or_end != m_cached_values.end()) return Value { cached_value_or_end->value.cell() }; // 4. Let rawStrings be TemplateStrings of templateLiteral with argument true. auto& raw_strings = m_template_literal->raw_strings(); // 5. Let cookedStrings be TemplateStrings of templateLiteral with argument false. auto& expressions = m_template_literal->expressions(); // 6. Let count be the number of elements in the List cookedStrings. // NOTE: Only the even expression in expression are the cooked strings // so we use rawStrings for the size here VERIFY(raw_strings.size() == (expressions.size() + 1) / 2); auto count = raw_strings.size(); // 7. Assert: count ≤ 2^32 - 1. VERIFY(count <= 0xffffffff); // 8. Let template be ! ArrayCreate(count). // NOTE: We don't set count since we push the values using append which // would then append after count. Same for 9. auto* template_ = MUST(Array::create(realm, 0)); // 9. Let rawObj be ! ArrayCreate(count). auto* raw_obj = MUST(Array::create(realm, 0)); // 10. Let index be 0. // 11. Repeat, while index < count, for (size_t i = 0; i < count; ++i) { auto cooked_string_index = i * 2; // a. Let prop be ! ToString(𝔽(index)). // b. Let cookedValue be cookedStrings[index]. auto cooked_value = TRY(expressions[cooked_string_index].execute(interpreter)).release_value(); // NOTE: If the string contains invalid escapes we get a null expression here, // which we then convert to the expected `undefined` TV. See // 12.9.6.1 Static Semantics: TV, https://tc39.es/ecma262/#sec-static-semantics-tv if (cooked_value.is_null()) cooked_value = js_undefined(); // c. Perform ! DefinePropertyOrThrow(template, prop, PropertyDescriptor { [[Value]]: cookedValue, [[Writable]]: false, [[Enumerable]]: true, [[Configurable]]: false }). template_->indexed_properties().append(cooked_value); // d. Let rawValue be the String value rawStrings[index]. // e. Perform ! DefinePropertyOrThrow(rawObj, prop, PropertyDescriptor { [[Value]]: rawValue, [[Writable]]: false, [[Enumerable]]: true, [[Configurable]]: false }). raw_obj->indexed_properties().append(TRY(raw_strings[i].execute(interpreter)).release_value()); // f. Set index to index + 1. } // 12. Perform ! SetIntegrityLevel(rawObj, frozen). MUST(raw_obj->set_integrity_level(Object::IntegrityLevel::Frozen)); // 13. Perform ! DefinePropertyOrThrow(template, "raw", PropertyDescriptor { [[Value]]: rawObj, [[Writable]]: false, [[Enumerable]]: false, [[Configurable]]: false }). template_->define_direct_property(interpreter.vm().names.raw, raw_obj, 0); // 14. Perform ! SetIntegrityLevel(template, frozen). MUST(template_->set_integrity_level(Object::IntegrityLevel::Frozen)); // 15. Append the Record { [[Site]]: templateLiteral, [[Array]]: template } to templateRegistry. m_cached_values.set(&realm, make_handle(template_)); // 16. Return template. return template_; } 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 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& global_object = interpreter.global_object(); 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(vm, parameter, false)); }, [&](NonnullRefPtr 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(vm, name, false)); }); }); // 4. Set the running execution context's LexicalEnvironment to catchEnv. vm.running_execution_context().lexical_environment = catch_environment; // 5. Let status be Completion(BindingInitialization of CatchParameter with arguments thrownValue and catchEnv). auto status = m_handler->parameter().visit( [&](FlyString const& parameter) { return catch_environment->initialize_binding(vm, parameter, thrown_value); }, [&](NonnullRefPtr 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 ? status. return status.release_error(); } // 7. Let B be the result of evaluating Block. auto handler_result = m_handler->body().execute(interpreter); // 8. Set the running execution context's LexicalEnvironment to oldEnv. vm.running_execution_context().lexical_environment = old_environment; // 9. Return ? B. return handler_result; }; Completion result; // 1. Let B be the result of evaluating Block. auto block_result = m_block->execute(interpreter); // TryStatement : try Block Catch // TryStatement : try Block Catch Finally if (m_handler) { // 2. If B.[[Type]] is throw, let C be Completion(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); // 5. If F.[[Type]] is normal, set F to C. if (finalizer_result.type() == Completion::Type::Normal) finalizer_result = move(result); // 6. Return ? UpdateEmpty(F, undefined). return finalizer_result.update_empty(js_undefined()); } // 4. Return ? UpdateEmpty(C, undefined). return result.update_empty(js_undefined()); } Completion CatchClause::execute(Interpreter& interpreter) 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) 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)).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) const { // 1. Let newLabelSet be a new empty List. // 2. Return ? LabelledEvaluation of this BreakableStatement with argument newLabelSet. return labelled_evaluation(interpreter, *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) 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 { // 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)).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) -> Completion { // CaseBlock : { } if (m_cases.is_empty()) { // 1. Return undefined. return js_undefined(); } NonnullRefPtrVector case_clauses_1; NonnullRefPtrVector case_clauses_2; RefPtr 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); // 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 ? UpdateEmpty(R, V). if (result.is_abrupt()) return result.update_empty(last_value); } } // 5. Return V. return 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 a new empty List. // 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); // 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 ? 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 a new empty List. // 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); // 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 ? UpdateEmpty(R, V). if (result.is_abrupt()) return result.update_empty(last_value); } } } // 10. If foundInB is true, return V. if (found_in_b) return last_value; // 11. Let R be the result of evaluating DefaultClause. auto result = default_clause->evaluate_statements(interpreter); // 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 ? 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); // 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 ? UpdateEmpty(R, V). if (result.is_abrupt()) return result.update_empty(last_value); } // 16. Return V. return 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)).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(interpreter, block_environment); // 6. Set the running execution context's LexicalEnvironment to blockEnv. vm.running_execution_context().lexical_environment = block_environment; } // 7. Let R be Completion(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) 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) const { InterpreterNodeScope node_scope { interpreter, *this }; // BreakStatement : break ; if (m_target_label.is_null()) { // 1. Return Completion Record { [[Type]]: break, [[Value]]: empty, [[Target]]: empty }. return { Completion::Type::Break, {}, {} }; } // BreakStatement : break LabelIdentifier ; // 1. Let label be the StringValue of LabelIdentifier. // 2. Return Completion Record { [[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) const { InterpreterNodeScope node_scope { interpreter, *this }; // ContinueStatement : continue ; if (m_target_label.is_null()) { // 1. Return Completion Record { [[Type]]: continue, [[Value]]: empty, [[Target]]: empty }. return { Completion::Type::Continue, {}, {} }; } // ContinueStatement : continue LabelIdentifier ; // 1. Let label be the StringValue of LabelIdentifier. // 2. Return Completion Record { [[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) 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)).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); } // 4. Else, else { // a. Let falseRef be the result of evaluating the second AssignmentExpression. // b. Return ? GetValue(falseRef). return m_alternate->execute(interpreter); } } 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) 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)).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) 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. Return a new implementation-defined Completion Record. VERIFY_NOT_REACHED(); } // 2. Else, else { // a. Return empty. return Optional {}; } } ThrowCompletionOr ScopeNode::for_each_lexically_scoped_declaration(ThrowCompletionOrVoidCallback&& callback) const { for (auto& declaration : m_lexical_declarations) TRY(callback(declaration)); return {}; } ThrowCompletionOr ScopeNode::for_each_lexically_declared_name(ThrowCompletionOrVoidCallback&& callback) const { for (auto const& declaration : m_lexical_declarations) { TRY(declaration.for_each_bound_name([&](auto const& name) { return callback(name); })); } return {}; } ThrowCompletionOr ScopeNode::for_each_var_declared_name(ThrowCompletionOrVoidCallback&& callback) const { for (auto& declaration : m_var_declarations) { TRY(declaration.for_each_bound_name([&](auto const& name) { return callback(name); })); } return {}; } ThrowCompletionOr ScopeNode::for_each_var_function_declaration_in_reverse_order(ThrowCompletionOrVoidCallback&& callback) const { for (ssize_t i = m_var_declarations.size() - 1; i >= 0; i--) { auto& declaration = m_var_declarations[i]; if (is(declaration)) TRY(callback(static_cast(declaration))); } return {}; } ThrowCompletionOr ScopeNode::for_each_var_scoped_variable_declaration(ThrowCompletionOrVoidCallback&& callback) const { for (auto& declaration : m_var_declarations) { if (!is(declaration)) { VERIFY(is(declaration)); TRY(callback(static_cast(declaration))); } } return {}; } ThrowCompletionOr ScopeNode::for_each_function_hoistable_with_annexB_extension(ThrowCompletionOrVoidCallback&& 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(function))); } return {}; } void ScopeNode::add_lexical_declaration(NonnullRefPtr declaration) { m_lexical_declarations.append(move(declaration)); } void ScopeNode::add_var_scoped_declaration(NonnullRefPtr declaration) { m_var_declarations.append(move(declaration)); } void ScopeNode::add_hoisted_function(NonnullRefPtr 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) const { InterpreterNodeScope node_scope { interpreter, *this }; // 1. Return empty. return Optional {}; } 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) const { InterpreterNodeScope node_scope { interpreter, *this }; auto& vm = interpreter.vm(); if (!is_default_export()) { if (m_statement) { // 1. Return the result of evaluating . return m_statement->execute(interpreter); } // 1. Return empty. return Optional {}; } VERIFY(m_statement); // ExportDeclaration : export default HoistableDeclaration if (is(*m_statement)) { // 1. Return the result of evaluating HoistableDeclaration. return m_statement->execute(interpreter); } // ExportDeclaration : export default ClassDeclaration // ClassDeclaration: class BindingIdentifier[?Yield, ?Await] ClassTail[?Yield, ?Await] if (is(*m_statement)) { auto const& class_declaration = static_cast(*m_statement); // 1. Let value be ? BindingClassDeclarationEvaluation of ClassDeclaration. auto value = TRY(binding_class_declaration_evaluation(interpreter, 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 empty. return Optional {}; } // ExportDeclaration : export default ClassDeclaration // ClassDeclaration: [+Default] class ClassTail [?Yield, ?Await] if (is(*m_statement)) { auto& class_expression = static_cast(*m_statement); // 1. Let value be ? BindingClassDeclarationEvaluation of ClassDeclaration. auto value = TRY(binding_class_declaration_evaluation(interpreter, 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(vm, ExportStatement::local_name_for_default, value, env)); } // 4. Return empty. return Optional {}; } // 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(vm.named_evaluation_if_anonymous_function(*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(vm, ExportStatement::local_name_for_default, value, env)); // 5. Return empty. return Optional {}; } 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(Interpreter& interpreter, Environment* environment) const { // See also B.3.2.6 Changes to BlockDeclarationInstantiation, https://tc39.es/ecma262/#sec-web-compat-blockdeclarationinstantiation auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); VERIFY(environment); auto* private_environment = 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(vm, name, true)); } else { if (!MUST(environment->has_binding(name))) MUST(environment->create_mutable_binding(vm, name, false)); } }); if (is(declaration)) { auto& function_declaration = static_cast(declaration); auto* function = ECMAScriptFunctionObject::create(realm, 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(*environment)); static_cast(*environment).initialize_or_set_mutable_binding({}, vm, function_declaration.name(), function); } }); } // 16.1.7 GlobalDeclarationInstantiation ( script, env ), https://tc39.es/ecma262/#sec-globaldeclarationinstantiation ThrowCompletionOr Program::global_declaration_instantiation(Interpreter& interpreter, GlobalEnvironment& global_environment) const { auto& global_object = interpreter.global_object(); auto& vm = interpreter.vm(); auto& realm = *global_object.associated_realm(); // 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 { // a. If env.HasVarDeclaration(name) is true, throw a SyntaxError exception. if (global_environment.has_var_declaration(name)) return vm.throw_completion(ErrorType::TopLevelVariableAlreadyDeclared, name); // b. If env.HasLexicalDeclaration(name) is true, throw a SyntaxError exception. if (global_environment.has_lexical_declaration(name)) return vm.throw_completion(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 vm.throw_completion(ErrorType::RestrictedGlobalProperty, name); return {}; })); // 4. For each element name of varNames, do TRY(for_each_var_declared_name([&](auto const& name) -> ThrowCompletionOr { // a. If env.HasLexicalDeclaration(name) is true, throw a SyntaxError exception. if (global_environment.has_lexical_declaration(name)) return vm.throw_completion(ErrorType::TopLevelVariableAlreadyDeclared, name); return {}; })); // 5. Let varDeclarations be the VarScopedDeclarations of script. // 6. Let functionsToInitialize be a new empty List. Vector functions_to_initialize; // 7. Let declaredFunctionNames be a new empty List. HashTable 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 { // 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 vm.throw_completion(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 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 { // 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 vm.throw_completion(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 { // 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 unused. 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 { // 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(vm, name, true)); } // ii. Else, else { // 1. Perform ? env.CreateMutableBinding(dn, false). TRY(global_environment.create_mutable_binding(vm, 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(realm, 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 unused. return {}; } ModuleRequest::ModuleRequest(FlyString module_specifier_, Vector 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; }); } }