/* * Copyright (c) 2020-2021, Andreas Kling * Copyright (c) 2020-2021, Linus Groh * * 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 #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 RefPtr vm; Vector repl_statements; class ReplObject final : public JS::GlobalObject { JS_OBJECT(ReplObject, JS::GlobalObject); public: ReplObject() = default; virtual void initialize_global_object() override; virtual ~ReplObject() override = default; private: JS_DECLARE_NATIVE_FUNCTION(exit_interpreter); JS_DECLARE_NATIVE_FUNCTION(repl_help); JS_DECLARE_NATIVE_FUNCTION(load_file); JS_DECLARE_NATIVE_FUNCTION(save_to_file); }; class ScriptObject final : public JS::GlobalObject { JS_OBJECT(ScriptObject, JS::GlobalObject); public: ScriptObject() = default; virtual void initialize_global_object() override; virtual ~ScriptObject() override = default; private: JS_DECLARE_NATIVE_FUNCTION(load_file); }; static bool s_dump_ast = false; static bool s_dump_bytecode = false; static bool s_run_bytecode = false; static bool s_opt_bytecode = false; static bool s_as_module = false; static bool s_print_last_result = false; static RefPtr s_editor; static String s_history_path = String::formatted("{}/.js-history", Core::StandardPaths::home_directory()); static int s_repl_line_level = 0; static bool s_fail_repl = false; static String prompt_for_level(int level) { static StringBuilder prompt_builder; prompt_builder.clear(); prompt_builder.append("> "); for (auto i = 0; i < level; ++i) prompt_builder.append(" "); return prompt_builder.build(); } static String read_next_piece() { StringBuilder piece; auto line_level_delta_for_next_line { 0 }; do { auto line_result = s_editor->get_line(prompt_for_level(s_repl_line_level)); line_level_delta_for_next_line = 0; if (line_result.is_error()) { s_fail_repl = true; return ""; } auto& line = line_result.value(); s_editor->add_to_history(line); piece.append(line); piece.append('\n'); auto lexer = JS::Lexer(line); enum { NotInLabelOrObjectKey, InLabelOrObjectKeyIdentifier, InLabelOrObjectKey } label_state { NotInLabelOrObjectKey }; for (JS::Token token = lexer.next(); token.type() != JS::TokenType::Eof; token = lexer.next()) { switch (token.type()) { case JS::TokenType::BracketOpen: case JS::TokenType::CurlyOpen: case JS::TokenType::ParenOpen: label_state = NotInLabelOrObjectKey; s_repl_line_level++; break; case JS::TokenType::BracketClose: case JS::TokenType::CurlyClose: case JS::TokenType::ParenClose: label_state = NotInLabelOrObjectKey; s_repl_line_level--; break; case JS::TokenType::Identifier: case JS::TokenType::StringLiteral: if (label_state == NotInLabelOrObjectKey) label_state = InLabelOrObjectKeyIdentifier; else label_state = NotInLabelOrObjectKey; break; case JS::TokenType::Colon: if (label_state == InLabelOrObjectKeyIdentifier) label_state = InLabelOrObjectKey; else label_state = NotInLabelOrObjectKey; break; default: break; } } if (label_state == InLabelOrObjectKey) { // If there's a label or object literal key at the end of this line, // prompt for more lines but do not change the line level. line_level_delta_for_next_line += 1; } } while (s_repl_line_level + line_level_delta_for_next_line > 0); return piece.to_string(); } static void print_value(JS::Value value, HashTable& seen_objects); static void print_type(FlyString const& name) { out("[\033[36;1m{}\033[0m]", name); } static void print_separator(bool& first) { out(first ? " " : ", "); first = false; } static void print_array(JS::Array& array, HashTable& seen_objects) { out("["); bool first = true; for (auto it = array.indexed_properties().begin(false); it != array.indexed_properties().end(); ++it) { print_separator(first); auto value = array.get(it.index()); // The V8 repl doesn't throw an exception here, and instead just // prints 'undefined'. We may choose to replicate that behavior in // the future, but for now lets just catch the error if (vm->exception()) return; print_value(value, seen_objects); } if (!first) out(" "); out("]"); } static void print_object(JS::Object& object, HashTable& seen_objects) { out("{{"); bool first = true; for (auto& entry : object.indexed_properties()) { print_separator(first); out("\"\033[33;1m{}\033[0m\": ", entry.index()); auto value = object.get(entry.index()); // The V8 repl doesn't throw an exception here, and instead just // prints 'undefined'. We may choose to replicate that behavior in // the future, but for now lets just catch the error if (vm->exception()) return; print_value(value, seen_objects); } for (auto& it : object.shape().property_table_ordered()) { print_separator(first); if (it.key.is_string()) { out("\"\033[33;1m{}\033[0m\": ", it.key.to_display_string()); } else { out("[\033[33;1m{}\033[0m]: ", it.key.to_display_string()); } print_value(object.get_direct(it.value.offset), seen_objects); } if (!first) out(" "); out("}}"); } static void print_function(JS::Object const& object, HashTable&) { print_type(object.class_name()); if (is(object)) out(" {}", static_cast(object).name()); else if (is(object)) out(" {}", static_cast(object).name()); } static void print_date(JS::Object const& object, HashTable&) { print_type("Date"); out(" \033[34;1m{}\033[0m", static_cast(object).string()); } static void print_error(JS::Object const& object, HashTable& seen_objects) { auto name = object.get_without_side_effects(vm->names.name).value_or(JS::js_undefined()); auto message = object.get_without_side_effects(vm->names.message).value_or(JS::js_undefined()); if (name.is_accessor() || message.is_accessor()) { print_value(&object, seen_objects); } else { auto name_string = name.to_string_without_side_effects(); auto message_string = message.to_string_without_side_effects(); print_type(name_string); if (!message_string.is_empty()) out(" \033[31;1m{}\033[0m", message_string); } } static void print_regexp_object(JS::Object const& object, HashTable&) { auto& regexp_object = static_cast(object); // Use RegExp.prototype.source rather than RegExpObject::pattern() so we get proper escaping auto source = regexp_object.get("source").to_primitive_string(object.global_object())->string(); print_type("RegExp"); out(" \033[34;1m/{}/{}\033[0m", source, regexp_object.flags()); } static void print_proxy_object(JS::Object const& object, HashTable& seen_objects) { auto& proxy_object = static_cast(object); print_type("Proxy"); out("\n target: "); print_value(&proxy_object.target(), seen_objects); out("\n handler: "); print_value(&proxy_object.handler(), seen_objects); } static void print_map(JS::Object const& object, HashTable& seen_objects) { auto& map = static_cast(object); auto& entries = map.entries(); print_type("Map"); out(" {{"); bool first = true; for (auto& entry : entries) { print_separator(first); print_value(entry.key, seen_objects); out(" => "); print_value(entry.value, seen_objects); } if (!first) out(" "); out("}}"); } static void print_set(JS::Object const& object, HashTable& seen_objects) { auto& set = static_cast(object); auto& values = set.values(); print_type("Set"); out(" {{"); bool first = true; for (auto& value : values) { print_separator(first); print_value(value, seen_objects); } if (!first) out(" "); out("}}"); } static void print_promise(JS::Object const& object, HashTable& seen_objects) { auto& promise = static_cast(object); print_type("Promise"); switch (promise.state()) { case JS::Promise::State::Pending: out("\n state: "); out("\033[36;1mPending\033[0m"); break; case JS::Promise::State::Fulfilled: out("\n state: "); out("\033[32;1mFulfilled\033[0m"); out("\n result: "); print_value(promise.result(), seen_objects); break; case JS::Promise::State::Rejected: out("\n state: "); out("\033[31;1mRejected\033[0m"); out("\n result: "); print_value(promise.result(), seen_objects); break; default: VERIFY_NOT_REACHED(); } } static void print_array_buffer(JS::Object const& object, HashTable& seen_objects) { auto& array_buffer = static_cast(object); auto& buffer = array_buffer.buffer(); auto byte_length = array_buffer.byte_length(); print_type("ArrayBuffer"); out("\n byteLength: "); print_value(JS::Value((double)byte_length), seen_objects); if (!byte_length) return; outln(); for (size_t i = 0; i < byte_length; ++i) { out("{:02x}", buffer[i]); if (i + 1 < byte_length) { if ((i + 1) % 32 == 0) outln(); else if ((i + 1) % 16 == 0) out(" "); else out(" "); } } } template static void print_number(T number) requires IsArithmetic { out("\033[35;1m"); out("{}", number); out("\033[0m"); } static void print_typed_array(JS::Object const& object, HashTable& seen_objects) { auto& typed_array_base = static_cast(object); auto& array_buffer = *typed_array_base.viewed_array_buffer(); auto length = typed_array_base.array_length(); print_type(object.class_name()); out("\n length: "); print_value(JS::Value(length), seen_objects); out("\n byteLength: "); print_value(JS::Value(typed_array_base.byte_length()), seen_objects); out("\n buffer: "); print_type("ArrayBuffer"); if (array_buffer.is_detached()) out(" (detached)"); out(" @ {:p}", &array_buffer); if (!length || array_buffer.is_detached()) return; outln(); // FIXME: This kinda sucks. #define __JS_ENUMERATE(ClassName, snake_name, PrototypeName, ConstructorName, ArrayType) \ if (is(object)) { \ out("[ "); \ auto& typed_array = static_cast(typed_array_base); \ auto data = typed_array.data(); \ for (size_t i = 0; i < length; ++i) { \ if (i > 0) \ out(", "); \ print_number(data[i]); \ } \ out(" ]"); \ return; \ } JS_ENUMERATE_TYPED_ARRAYS #undef __JS_ENUMERATE VERIFY_NOT_REACHED(); } static void print_data_view(JS::Object const& object, HashTable& seen_objects) { auto& data_view = static_cast(object); print_type("DataView"); out("\n byteLength: "); print_value(JS::Value(data_view.byte_length()), seen_objects); out("\n byteOffset: "); print_value(JS::Value(data_view.byte_offset()), seen_objects); out("\n buffer: "); print_type("ArrayBuffer"); out(" @ {:p}", data_view.viewed_array_buffer()); } static void print_temporal_calendar(JS::Object const& object, HashTable& seen_objects) { auto& calendar = static_cast(object); print_type("Temporal.Calendar"); out(" "); print_value(JS::js_string(object.vm(), calendar.identifier()), seen_objects); } static void print_temporal_duration(JS::Object const& object, HashTable&) { auto& duration = static_cast(object); print_type("Temporal.Duration"); out(" \033[34;1m{} y, {} M, {} w, {} d, {} h, {} m, {} s, {} ms, {} us, {} ns\033[0m", duration.years(), duration.months(), duration.weeks(), duration.days(), duration.hours(), duration.minutes(), duration.seconds(), duration.milliseconds(), duration.microseconds(), duration.nanoseconds()); } static void print_temporal_instant(JS::Object const& object, HashTable& seen_objects) { auto& instant = static_cast(object); print_type("Temporal.Instant"); out(" "); // FIXME: Print human readable date and time, like in print_date() - ideally handling arbitrarily large values since we get a bigint. print_value(&instant.nanoseconds(), seen_objects); } static void print_temporal_plain_date(JS::Object const& object, HashTable& seen_objects) { auto& plain_date = static_cast(object); print_type("Temporal.PlainDate"); out(" \033[34;1m{:04}-{:02}-{:02}\033[0m", plain_date.iso_year(), plain_date.iso_month(), plain_date.iso_day()); out("\n calendar: "); print_value(&plain_date.calendar(), seen_objects); } static void print_temporal_plain_date_time(JS::Object const& object, HashTable& seen_objects) { auto& plain_date_time = static_cast(object); print_type("Temporal.PlainDateTime"); out(" \033[34;1m{:04}-{:02}-{:02} {:02}:{:02}:{:02}.{:03}{:03}{:03}\033[0m", plain_date_time.iso_year(), plain_date_time.iso_month(), plain_date_time.iso_day(), plain_date_time.iso_hour(), plain_date_time.iso_minute(), plain_date_time.iso_second(), plain_date_time.iso_millisecond(), plain_date_time.iso_microsecond(), plain_date_time.iso_nanosecond()); out("\n calendar: "); print_value(&plain_date_time.calendar(), seen_objects); } static void print_temporal_plain_month_day(JS::Object const& object, HashTable& seen_objects) { auto& plain_month_day = static_cast(object); print_type("Temporal.PlainMonthDay"); // Also has an [[ISOYear]] internal slot, but showing that here seems rather unexpected. out(" \033[34;1m{:02}-{:02}\033[0m", plain_month_day.iso_month(), plain_month_day.iso_day()); out("\n calendar: "); print_value(&plain_month_day.calendar(), seen_objects); } static void print_temporal_plain_time(JS::Object const& object, HashTable& seen_objects) { auto& plain_time = static_cast(object); print_type("Temporal.PlainTime"); out(" \033[34;1m{:02}:{:02}:{:02}.{:03}{:03}{:03}\033[0m", plain_time.iso_hour(), plain_time.iso_minute(), plain_time.iso_second(), plain_time.iso_millisecond(), plain_time.iso_microsecond(), plain_time.iso_nanosecond()); out("\n calendar: "); print_value(&plain_time.calendar(), seen_objects); } static void print_temporal_plain_year_month(JS::Object const& object, HashTable& seen_objects) { auto& plain_year_month = static_cast(object); print_type("Temporal.PlainYearMonth"); // Also has an [[ISODay]] internal slot, but showing that here seems rather unexpected. out(" \033[34;1m{:04}-{:02}\033[0m", plain_year_month.iso_year(), plain_year_month.iso_month()); out("\n calendar: "); print_value(&plain_year_month.calendar(), seen_objects); } static void print_temporal_time_zone(JS::Object const& object, HashTable& seen_objects) { auto& time_zone = static_cast(object); print_type("Temporal.TimeZone"); out(" "); print_value(JS::js_string(object.vm(), time_zone.identifier()), seen_objects); if (time_zone.offset_nanoseconds().has_value()) { out("\n offset (ns): "); print_value(JS::Value(*time_zone.offset_nanoseconds()), seen_objects); } } static void print_temporal_zoned_date_time(JS::Object const& object, HashTable& seen_objects) { auto& zoned_date_time = static_cast(object); print_type("Temporal.ZonedDateTime"); out("\n epochNanoseconds: "); print_value(&zoned_date_time.nanoseconds(), seen_objects); out("\n timeZone: "); print_value(&zoned_date_time.time_zone(), seen_objects); out("\n calendar: "); print_value(&zoned_date_time.calendar(), seen_objects); } static void print_intl_display_names(JS::Object const& object, HashTable& seen_objects) { auto& display_names = static_cast(object); print_type("Intl.DisplayNames"); out("\n locale: "); print_value(js_string(object.vm(), display_names.locale()), seen_objects); out("\n type: "); print_value(js_string(object.vm(), display_names.type_string()), seen_objects); out("\n style: "); print_value(js_string(object.vm(), display_names.style_string()), seen_objects); out("\n fallback: "); print_value(js_string(object.vm(), display_names.fallback_string()), seen_objects); } static void print_intl_locale(JS::Object const& object, HashTable& seen_objects) { auto& locale = static_cast(object); print_type("Intl.Locale"); out("\n locale: "); print_value(js_string(object.vm(), locale.locale()), seen_objects); if (locale.has_calendar()) { out("\n calendar: "); print_value(js_string(object.vm(), locale.calendar()), seen_objects); } if (locale.has_case_first()) { out("\n caseFirst: "); print_value(js_string(object.vm(), locale.case_first()), seen_objects); } if (locale.has_collation()) { out("\n collation: "); print_value(js_string(object.vm(), locale.collation()), seen_objects); } if (locale.has_hour_cycle()) { out("\n hourCycle: "); print_value(js_string(object.vm(), locale.hour_cycle()), seen_objects); } if (locale.has_numbering_system()) { out("\n numberingSystem: "); print_value(js_string(object.vm(), locale.numbering_system()), seen_objects); } out("\n numeric: "); print_value(JS::Value(locale.numeric()), seen_objects); } static void print_intl_list_format(JS::Object const& object, HashTable& seen_objects) { auto& list_format = static_cast(object); print_type("Intl.ListFormat"); out("\n locale: "); print_value(js_string(object.vm(), list_format.locale()), seen_objects); out("\n type: "); print_value(js_string(object.vm(), list_format.type_string()), seen_objects); out("\n style: "); print_value(js_string(object.vm(), list_format.style_string()), seen_objects); } static void print_intl_number_format(JS::Object const& object, HashTable& seen_objects) { auto& number_format = static_cast(object); print_type("Intl.NumberFormat"); out("\n locale: "); print_value(js_string(object.vm(), number_format.locale()), seen_objects); out("\n dataLocale: "); print_value(js_string(object.vm(), number_format.data_locale()), seen_objects); out("\n numberingSystem: "); print_value(js_string(object.vm(), number_format.numbering_system()), seen_objects); out("\n style: "); print_value(js_string(object.vm(), number_format.style_string()), seen_objects); if (number_format.has_currency()) { out("\n currency: "); print_value(js_string(object.vm(), number_format.currency()), seen_objects); } if (number_format.has_currency_display()) { out("\n currencyDisplay: "); print_value(js_string(object.vm(), number_format.currency_display_string()), seen_objects); } if (number_format.has_currency_sign()) { out("\n currencySign: "); print_value(js_string(object.vm(), number_format.currency_sign_string()), seen_objects); } if (number_format.has_unit()) { out("\n unit: "); print_value(js_string(object.vm(), number_format.unit()), seen_objects); } if (number_format.has_unit_display()) { out("\n unitDisplay: "); print_value(js_string(object.vm(), number_format.unit_display_string()), seen_objects); } out("\n minimumIntegerDigits: "); print_value(JS::Value(number_format.min_integer_digits()), seen_objects); if (number_format.has_min_fraction_digits()) { out("\n minimumFractionDigits: "); print_value(JS::Value(number_format.min_fraction_digits()), seen_objects); } if (number_format.has_max_fraction_digits()) { out("\n maximumFractionDigits: "); print_value(JS::Value(number_format.max_fraction_digits()), seen_objects); } if (number_format.has_min_significant_digits()) { out("\n minimumSignificantDigits: "); print_value(JS::Value(number_format.min_significant_digits()), seen_objects); } if (number_format.has_max_significant_digits()) { out("\n maximumSignificantDigits: "); print_value(JS::Value(number_format.max_significant_digits()), seen_objects); } out("\n useGrouping: "); print_value(JS::Value(number_format.use_grouping()), seen_objects); out("\n roundingType: "); print_value(js_string(object.vm(), number_format.rounding_type_string()), seen_objects); out("\n notation: "); print_value(js_string(object.vm(), number_format.notation_string()), seen_objects); if (number_format.has_compact_display()) { out("\n compactDisplay: "); print_value(js_string(object.vm(), number_format.compact_display_string()), seen_objects); } out("\n signDisplay: "); print_value(js_string(object.vm(), number_format.sign_display_string()), seen_objects); } static void print_primitive_wrapper_object(FlyString const& name, JS::Object const& object, HashTable& seen_objects) { // BooleanObject, NumberObject, StringObject print_type(name); out(" "); print_value(object.value_of(), seen_objects); } static void print_value(JS::Value value, HashTable& seen_objects) { if (value.is_empty()) { out("\033[34;1m\033[0m"); return; } if (value.is_object()) { if (seen_objects.contains(&value.as_object())) { // FIXME: Maybe we should only do this for circular references, // not for all reoccurring objects. out("", &value.as_object()); return; } seen_objects.set(&value.as_object()); } if (value.is_object()) { auto& object = value.as_object(); if (is(object)) return print_array(static_cast(object), seen_objects); if (object.is_function()) return print_function(object, seen_objects); if (is(object)) return print_date(object, seen_objects); if (is(object)) return print_error(object, seen_objects); if (is(object)) return print_regexp_object(object, seen_objects); if (is(object)) return print_map(object, seen_objects); if (is(object)) return print_set(object, seen_objects); if (is(object)) return print_data_view(object, seen_objects); if (is(object)) return print_proxy_object(object, seen_objects); if (is(object)) return print_promise(object, seen_objects); if (is(object)) return print_array_buffer(object, seen_objects); if (object.is_typed_array()) return print_typed_array(object, seen_objects); if (is(object)) return print_primitive_wrapper_object("String", object, seen_objects); if (is(object)) return print_primitive_wrapper_object("Number", object, seen_objects); if (is(object)) return print_primitive_wrapper_object("Boolean", object, seen_objects); if (is(object)) return print_temporal_calendar(object, seen_objects); if (is(object)) return print_temporal_duration(object, seen_objects); if (is(object)) return print_temporal_instant(object, seen_objects); if (is(object)) return print_temporal_plain_date(object, seen_objects); if (is(object)) return print_temporal_plain_date_time(object, seen_objects); if (is(object)) return print_temporal_plain_month_day(object, seen_objects); if (is(object)) return print_temporal_plain_time(object, seen_objects); if (is(object)) return print_temporal_plain_year_month(object, seen_objects); if (is(object)) return print_temporal_time_zone(object, seen_objects); if (is(object)) return print_temporal_zoned_date_time(object, seen_objects); if (is(object)) return print_intl_display_names(object, seen_objects); if (is(object)) return print_intl_locale(object, seen_objects); if (is(object)) return print_intl_list_format(object, seen_objects); if (is(object)) return print_intl_number_format(object, seen_objects); return print_object(object, seen_objects); } if (value.is_string()) out("\033[32;1m"); else if (value.is_number() || value.is_bigint()) out("\033[35;1m"); else if (value.is_boolean()) out("\033[33;1m"); else if (value.is_null()) out("\033[33;1m"); else if (value.is_undefined()) out("\033[34;1m"); if (value.is_string()) out("\""); else if (value.is_negative_zero()) out("-"); out("{}", value.to_string_without_side_effects()); if (value.is_string()) out("\""); out("\033[0m"); } static void print(JS::Value value) { HashTable seen_objects; print_value(value, seen_objects); outln(); } static bool write_to_file(String const& path) { int fd = open(path.characters(), O_WRONLY | O_CREAT | O_TRUNC, 0666); for (size_t i = 0; i < repl_statements.size(); i++) { auto line = repl_statements[i]; if (line.length() && i != repl_statements.size() - 1) { ssize_t nwritten = write(fd, line.characters(), line.length()); if (nwritten < 0) { close(fd); return false; } } if (i != repl_statements.size() - 1) { char ch = '\n'; ssize_t nwritten = write(fd, &ch, 1); if (nwritten != 1) { perror("write"); close(fd); return false; } } } close(fd); return true; } static bool parse_and_run(JS::Interpreter& interpreter, StringView const& source) { auto program_type = s_as_module ? JS::Program::Type::Module : JS::Program::Type::Script; auto parser = JS::Parser(JS::Lexer(source), program_type); auto program = parser.parse_program(); if (s_dump_ast) program->dump(0); if (parser.has_errors()) { auto error = parser.errors()[0]; auto hint = error.source_location_hint(source); if (!hint.is_empty()) outln("{}", hint); vm->throw_exception(interpreter.global_object(), error.to_string()); } else { if (s_dump_bytecode || s_run_bytecode) { auto unit = JS::Bytecode::Generator::generate(*program); if (s_opt_bytecode) { auto& passes = JS::Bytecode::Interpreter::optimization_pipeline(); passes.perform(unit); dbgln("Optimisation passes took {}us", passes.elapsed()); } if (s_dump_bytecode) { for (auto& block : unit.basic_blocks) block.dump(unit); if (!unit.string_table->is_empty()) { outln(); unit.string_table->dump(); } } if (s_run_bytecode) { JS::Bytecode::Interpreter bytecode_interpreter(interpreter.global_object(), interpreter.realm()); bytecode_interpreter.run(unit); } else { return true; } } else { interpreter.run(interpreter.global_object(), *program); } } auto handle_exception = [&] { auto* exception = vm->exception(); vm->clear_exception(); out("Uncaught exception: "); print(exception->value()); auto& traceback = exception->traceback(); if (traceback.size() > 1) { unsigned repetitions = 0; for (size_t i = 0; i < traceback.size(); ++i) { auto& traceback_frame = traceback[i]; if (i + 1 < traceback.size()) { auto& next_traceback_frame = traceback[i + 1]; if (next_traceback_frame.function_name == traceback_frame.function_name) { repetitions++; continue; } } if (repetitions > 4) { // If more than 5 (1 + >4) consecutive function calls with the same name, print // the name only once and show the number of repetitions instead. This prevents // printing ridiculously large call stacks of recursive functions. outln(" -> {}", traceback_frame.function_name); outln(" {} more calls", repetitions); } else { for (size_t j = 0; j < repetitions + 1; ++j) outln(" -> {}", traceback_frame.function_name); } repetitions = 0; } } }; if (vm->exception()) { handle_exception(); return false; } if (s_print_last_result) print(vm->last_value()); if (vm->exception()) { handle_exception(); return false; } return true; } static JS::Value load_file_impl(JS::VM& vm, JS::GlobalObject& global_object) { auto filename = vm.argument(0).to_string(global_object); if (vm.exception()) return {}; auto file = Core::File::construct(filename); if (!file->open(Core::OpenMode::ReadOnly)) { vm.throw_exception(global_object, String::formatted("Failed to open '{}': {}", filename, file->error_string())); return {}; } auto file_contents = file->read_all(); auto source = StringView { file_contents }; auto parser = JS::Parser(JS::Lexer(source)); auto program = parser.parse_program(); if (parser.has_errors()) { auto& error = parser.errors()[0]; vm.throw_exception(global_object, error.to_string()); return {}; } // FIXME: Use eval()-like semantics and execute in current scope? vm.interpreter().run(global_object, *program); return JS::js_undefined(); } void ReplObject::initialize_global_object() { Base::initialize_global_object(); define_direct_property("global", this, JS::Attribute::Enumerable); u8 attr = JS::Attribute::Configurable | JS::Attribute::Writable | JS::Attribute::Enumerable; define_native_function("exit", exit_interpreter, 0, attr); define_native_function("help", repl_help, 0, attr); define_native_function("load", load_file, 1, attr); define_native_function("save", save_to_file, 1, attr); } JS_DEFINE_NATIVE_FUNCTION(ReplObject::save_to_file) { if (!vm.argument_count()) return JS::Value(false); String save_path = vm.argument(0).to_string_without_side_effects(); StringView path = StringView(save_path.characters()); if (write_to_file(path)) { return JS::Value(true); } return JS::Value(false); } JS_DEFINE_NATIVE_FUNCTION(ReplObject::exit_interpreter) { if (!vm.argument_count()) exit(0); auto exit_code = vm.argument(0).to_number(global_object); if (::vm->exception()) return {}; exit(exit_code.as_double()); } JS_DEFINE_NATIVE_FUNCTION(ReplObject::repl_help) { outln("REPL commands:"); outln(" exit(code): exit the REPL with specified code. Defaults to 0."); outln(" help(): display this menu"); outln(" load(file): load given JS file into running session. For example: load(\"foo.js\")"); outln(" save(file): write REPL input history to the given file. For example: save(\"foo.txt\")"); return JS::js_undefined(); } JS_DEFINE_NATIVE_FUNCTION(ReplObject::load_file) { return load_file_impl(vm, global_object); } void ScriptObject::initialize_global_object() { Base::initialize_global_object(); define_direct_property("global", this, JS::Attribute::Enumerable); u8 attr = JS::Attribute::Configurable | JS::Attribute::Writable | JS::Attribute::Enumerable; define_native_function("load", load_file, 1, attr); } JS_DEFINE_NATIVE_FUNCTION(ScriptObject::load_file) { return load_file_impl(vm, global_object); } static void repl(JS::Interpreter& interpreter) { while (!s_fail_repl) { String piece = read_next_piece(); if (piece.is_empty()) continue; repl_statements.append(piece); parse_and_run(interpreter, piece); } } static Function interrupt_interpreter; static void sigint_handler() { interrupt_interpreter(); } class ReplConsoleClient final : public JS::ConsoleClient { public: ReplConsoleClient(JS::Console& console) : ConsoleClient(console) { } virtual JS::Value log() override { outln("{}", vm().join_arguments()); return JS::js_undefined(); } virtual JS::Value info() override { outln("(i) {}", vm().join_arguments()); return JS::js_undefined(); } virtual JS::Value debug() override { outln("\033[36;1m{}\033[0m", vm().join_arguments()); return JS::js_undefined(); } virtual JS::Value warn() override { outln("\033[33;1m{}\033[0m", vm().join_arguments()); return JS::js_undefined(); } virtual JS::Value error() override { outln("\033[31;1m{}\033[0m", vm().join_arguments()); return JS::js_undefined(); } virtual JS::Value clear() override { out("\033[3J\033[H\033[2J"); fflush(stdout); return JS::js_undefined(); } virtual JS::Value trace() override { outln("{}", vm().join_arguments()); auto trace = get_trace(); for (auto& function_name : trace) { if (function_name.is_empty()) function_name = ""; outln(" -> {}", function_name); } return JS::js_undefined(); } virtual JS::Value count() override { auto label = vm().argument_count() ? vm().argument(0).to_string_without_side_effects() : "default"; auto counter_value = m_console.counter_increment(label); outln("{}: {}", label, counter_value); return JS::js_undefined(); } virtual JS::Value count_reset() override { auto label = vm().argument_count() ? vm().argument(0).to_string_without_side_effects() : "default"; if (m_console.counter_reset(label)) outln("{}: 0", label); else outln("\033[33;1m\"{}\" doesn't have a count\033[0m", label); return JS::js_undefined(); } virtual JS::Value assert_() override { auto& vm = this->vm(); if (!vm.argument(0).to_boolean()) { if (vm.argument_count() > 1) { out("\033[31;1mAssertion failed:\033[0m"); outln(" {}", vm.join_arguments(1)); } else { outln("\033[31;1mAssertion failed\033[0m"); } } return JS::js_undefined(); } }; int main(int argc, char** argv) { bool gc_on_every_allocation = false; bool zombify_dead_cells = false; bool disable_syntax_highlight = false; Vector script_paths; Core::ArgsParser args_parser; args_parser.set_general_help("This is a JavaScript interpreter."); args_parser.add_option(s_dump_ast, "Dump the AST", "dump-ast", 'A'); args_parser.add_option(s_dump_bytecode, "Dump the bytecode", "dump-bytecode", 'd'); args_parser.add_option(s_run_bytecode, "Run the bytecode", "run-bytecode", 'b'); args_parser.add_option(s_opt_bytecode, "Optimize the bytecode", "optimize-bytecode", 'p'); args_parser.add_option(s_as_module, "Treat as module", "as-module", 'm'); args_parser.add_option(s_print_last_result, "Print last result", "print-last-result", 'l'); args_parser.add_option(gc_on_every_allocation, "GC on every allocation", "gc-on-every-allocation", 'g'); args_parser.add_option(zombify_dead_cells, "Zombify dead cells (to catch missing GC marks)", "zombify-dead-cells", 'z'); args_parser.add_option(disable_syntax_highlight, "Disable live syntax highlighting", "no-syntax-highlight", 's'); args_parser.add_positional_argument(script_paths, "Path to script files", "scripts", Core::ArgsParser::Required::No); args_parser.parse(argc, argv); bool syntax_highlight = !disable_syntax_highlight; vm = JS::VM::create(); // NOTE: These will print out both warnings when using something like Promise.reject().catch(...) - // which is, as far as I can tell, correct - a promise is created, rejected without handler, and a // handler then attached to it. The Node.js REPL doesn't warn in this case, so it's something we // might want to revisit at a later point and disable warnings for promises created this way. vm->on_promise_unhandled_rejection = [](auto& promise) { // FIXME: Optionally make print_value() to print to stderr out("WARNING: A promise was rejected without any handlers"); out(" (result: "); HashTable seen_objects; print_value(promise.result(), seen_objects); outln(")"); }; vm->on_promise_rejection_handled = [](auto& promise) { // FIXME: Optionally make print_value() to print to stderr out("WARNING: A handler was added to an already rejected promise"); out(" (result: "); HashTable seen_objects; print_value(promise.result(), seen_objects); outln(")"); }; OwnPtr interpreter; interrupt_interpreter = [&] { auto error = JS::Error::create(interpreter->global_object(), "Received SIGINT"); vm->throw_exception(interpreter->global_object(), error); }; if (script_paths.is_empty()) { s_print_last_result = true; interpreter = JS::Interpreter::create(*vm); ReplConsoleClient console_client(interpreter->global_object().console()); interpreter->global_object().console().set_client(console_client); interpreter->heap().set_should_collect_on_every_allocation(gc_on_every_allocation); interpreter->heap().set_zombify_dead_cells(zombify_dead_cells); interpreter->vm().set_underscore_is_last_value(true); s_editor = Line::Editor::construct(); s_editor->load_history(s_history_path); signal(SIGINT, [](int) { if (!s_editor->is_editing()) sigint_handler(); s_editor->save_history(s_history_path); }); s_editor->on_display_refresh = [syntax_highlight](Line::Editor& editor) { auto stylize = [&](Line::Span span, Line::Style styles) { if (syntax_highlight) editor.stylize(span, styles); }; editor.strip_styles(); size_t open_indents = s_repl_line_level; auto line = editor.line(); JS::Lexer lexer(line); bool indenters_starting_line = true; for (JS::Token token = lexer.next(); token.type() != JS::TokenType::Eof; token = lexer.next()) { auto length = Utf8View { token.value() }.length(); auto start = token.line_column() - 1; auto end = start + length; if (indenters_starting_line) { if (token.type() != JS::TokenType::ParenClose && token.type() != JS::TokenType::BracketClose && token.type() != JS::TokenType::CurlyClose) { indenters_starting_line = false; } else { --open_indents; } } switch (token.category()) { case JS::TokenCategory::Invalid: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::Red), Line::Style::Underline }); break; case JS::TokenCategory::Number: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::Magenta) }); break; case JS::TokenCategory::String: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::Green), Line::Style::Bold }); break; case JS::TokenCategory::Punctuation: break; case JS::TokenCategory::Operator: break; case JS::TokenCategory::Keyword: switch (token.type()) { case JS::TokenType::BoolLiteral: case JS::TokenType::NullLiteral: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::Yellow), Line::Style::Bold }); break; default: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::Blue), Line::Style::Bold }); break; } break; case JS::TokenCategory::ControlKeyword: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::Cyan), Line::Style::Italic }); break; case JS::TokenCategory::Identifier: stylize({ start, end, Line::Span::CodepointOriented }, { Line::Style::Foreground(Line::Style::XtermColor::White), Line::Style::Bold }); break; default: break; } } editor.set_prompt(prompt_for_level(open_indents)); }; auto complete = [&interpreter](Line::Editor const& editor) -> Vector { auto line = editor.line(editor.cursor()); JS::Lexer lexer { line }; enum { Initial, CompleteVariable, CompleteNullProperty, CompleteProperty, } mode { Initial }; StringView variable_name; StringView property_name; // we're only going to complete either // - // where N is part of the name of a variable // - .

// where N is the complete name of a variable and // P is part of the name of one of its properties auto js_token = lexer.next(); for (; js_token.type() != JS::TokenType::Eof; js_token = lexer.next()) { switch (mode) { case CompleteVariable: switch (js_token.type()) { case JS::TokenType::Period: // ... mode = CompleteNullProperty; break; default: // not a dot, reset back to initial mode = Initial; break; } break; case CompleteNullProperty: if (js_token.is_identifier_name()) { // ... mode = CompleteProperty; property_name = js_token.value(); } else { mode = Initial; } break; case CompleteProperty: // something came after the property access, reset to initial case Initial: if (js_token.type() == JS::TokenType::Identifier) { // ...... mode = CompleteVariable; variable_name = js_token.value(); } else { mode = Initial; } break; } } bool last_token_has_trivia = js_token.trivia().length() > 0; if (mode == CompleteNullProperty) { mode = CompleteProperty; property_name = ""; last_token_has_trivia = false; // [tab] is sensible to complete. } if (mode == Initial || last_token_has_trivia) return {}; // we do not know how to complete this Vector results; Function list_all_properties = [&results, &list_all_properties](JS::Shape const& shape, auto& property_pattern) { for (auto const& descriptor : shape.property_table()) { if (!descriptor.key.is_string()) continue; auto key = descriptor.key.as_string(); if (key.view().starts_with(property_pattern)) { Line::CompletionSuggestion completion { key, Line::CompletionSuggestion::ForSearch }; if (!results.contains_slow(completion)) { // hide duplicates results.append(String(key)); } } } if (auto const* prototype = shape.prototype()) { list_all_properties(prototype->shape(), property_pattern); } }; switch (mode) { case CompleteProperty: { auto maybe_variable = vm->get_variable(variable_name, interpreter->global_object()); if (maybe_variable.is_empty()) { maybe_variable = interpreter->global_object().get(FlyString(variable_name)); if (maybe_variable.is_empty()) break; } auto variable = maybe_variable; if (!variable.is_object()) break; auto const* object = variable.to_object(interpreter->global_object()); auto const& shape = object->shape(); list_all_properties(shape, property_name); if (results.size()) editor.suggest(property_name.length()); break; } case CompleteVariable: { auto const& variable = interpreter->global_object(); list_all_properties(variable.shape(), variable_name); if (results.size()) editor.suggest(variable_name.length()); break; } default: VERIFY_NOT_REACHED(); } return results; }; s_editor->on_tab_complete = move(complete); repl(*interpreter); s_editor->save_history(s_history_path); } else { interpreter = JS::Interpreter::create(*vm); ReplConsoleClient console_client(interpreter->global_object().console()); interpreter->global_object().console().set_client(console_client); interpreter->heap().set_should_collect_on_every_allocation(gc_on_every_allocation); interpreter->heap().set_zombify_dead_cells(zombify_dead_cells); signal(SIGINT, [](int) { sigint_handler(); }); StringBuilder builder; for (auto& path : script_paths) { auto file = Core::File::construct(path); if (!file->open(Core::OpenMode::ReadOnly)) { warnln("Failed to open {}: {}", path, file->error_string()); return 1; } auto file_contents = file->read_all(); auto source = StringView { file_contents }; builder.append(source); } if (!parse_and_run(*interpreter, builder.to_string())) return 1; } return 0; }