ladybird/Userland/Utilities/js.cpp
Andreas Kling b6d4eea7ac LibJS: Never give back virtual memory once it belongs to a cell type
Instead of returning HeapBlock memory to the kernel (or a non-type
specific shared cache), we now keep a BlockAllocator per CellAllocator
and implement "deallocation" by basically informing the kernel that we
don't need the physical memory right now.

This is done with MADV_FREE or MADV_DONTNEED if available, but for other
platforms (including SerenityOS) we munmap and then re-mmap the memory
to achieve the same effect. It's definitely clunky, so I've added a
FIXME about implementing the madvise options on SerenityOS too.

The important outcome of this change is that GC types that use a
type-specific allocator become immune to use-after-free type confusion
attacks, since their virtual addresses will only ever be re-used for
the same exact type again and again.

Fixes #22274
2023-12-31 15:35:56 +01:00

856 lines
32 KiB
C++

/*
* Copyright (c) 2020-2023, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2020-2023, Linus Groh <linusg@serenityos.org>
* Copyright (c) 2020-2022, Ali Mohammad Pur <mpfard@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/JsonValue.h>
#include <AK/StringBuilder.h>
#include <LibCore/ArgsParser.h>
#include <LibCore/ConfigFile.h>
#include <LibCore/StandardPaths.h>
#include <LibCore/System.h>
#include <LibJS/Bytecode/BasicBlock.h>
#include <LibJS/Bytecode/Generator.h>
#include <LibJS/Bytecode/Interpreter.h>
#include <LibJS/Console.h>
#include <LibJS/Contrib/Test262/GlobalObject.h>
#include <LibJS/Parser.h>
#include <LibJS/Print.h>
#include <LibJS/Runtime/ConsoleObject.h>
#include <LibJS/Runtime/DeclarativeEnvironment.h>
#include <LibJS/Runtime/GlobalEnvironment.h>
#include <LibJS/Runtime/JSONObject.h>
#include <LibJS/Runtime/StringPrototype.h>
#include <LibJS/Runtime/ValueInlines.h>
#include <LibJS/SourceTextModule.h>
#include <LibLine/Editor.h>
#include <LibMain/Main.h>
#include <LibTextCodec/Decoder.h>
#include <signal.h>
RefPtr<JS::VM> g_vm;
Vector<String> g_repl_statements;
JS::Handle<JS::Value> g_last_value = JS::make_handle(JS::js_undefined());
class ReplObject final : public JS::GlobalObject {
JS_OBJECT(ReplObject, JS::GlobalObject);
public:
ReplObject(JS::Realm& realm)
: GlobalObject(realm)
{
}
virtual void initialize(JS::Realm&) override;
virtual ~ReplObject() override = default;
private:
JS_DECLARE_NATIVE_FUNCTION(exit_interpreter);
JS_DECLARE_NATIVE_FUNCTION(repl_help);
JS_DECLARE_NATIVE_FUNCTION(save_to_file);
JS_DECLARE_NATIVE_FUNCTION(load_ini);
JS_DECLARE_NATIVE_FUNCTION(load_json);
JS_DECLARE_NATIVE_FUNCTION(last_value_getter);
JS_DECLARE_NATIVE_FUNCTION(print);
};
class ScriptObject final : public JS::GlobalObject {
JS_OBJECT(ScriptObject, JS::GlobalObject);
public:
ScriptObject(JS::Realm& realm)
: JS::GlobalObject(realm)
{
}
virtual void initialize(JS::Realm&) override;
virtual ~ScriptObject() override = default;
private:
JS_DECLARE_NATIVE_FUNCTION(load_ini);
JS_DECLARE_NATIVE_FUNCTION(load_json);
JS_DECLARE_NATIVE_FUNCTION(print);
};
static bool s_dump_ast = false;
static bool s_as_module = false;
static bool s_print_last_result = false;
static bool s_strip_ansi = false;
static bool s_disable_source_location_hints = false;
static RefPtr<Line::Editor> s_editor;
static String s_history_path = String {};
static int s_repl_line_level = 0;
static bool s_keep_running_repl = true;
static int s_exit_code = 0;
static ErrorOr<void> print(JS::Value value, Stream& stream)
{
JS::PrintContext print_context { .vm = *g_vm, .stream = stream, .strip_ansi = s_strip_ansi };
return JS::print(value, print_context);
}
enum class PrintTarget {
StandardError,
StandardOutput,
};
static ErrorOr<void> print(JS::Value value, PrintTarget target = PrintTarget::StandardOutput)
{
auto stream = TRY(target == PrintTarget::StandardError ? Core::File::standard_error() : Core::File::standard_output());
return print(value, *stream);
}
static ErrorOr<String> prompt_for_level(int level)
{
static StringBuilder prompt_builder;
prompt_builder.clear();
prompt_builder.append("> "sv);
for (auto i = 0; i < level; ++i)
prompt_builder.append(" "sv);
return prompt_builder.to_string();
}
static ErrorOr<String> read_next_piece()
{
StringBuilder piece;
auto line_level_delta_for_next_line { 0 };
do {
auto line_result = s_editor->get_line(TRY(prompt_for_level(s_repl_line_level)).to_byte_string());
line_level_delta_for_next_line = 0;
if (line_result.is_error()) {
s_keep_running_repl = false;
return String {};
}
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 ErrorOr<void> write_to_file(String const& path)
{
auto file = TRY(Core::File::open(path, Core::File::OpenMode::Write, 0666));
for (size_t i = 0; i < g_repl_statements.size(); i++) {
auto line = g_repl_statements[i].bytes();
if (line.size() > 0 && i != g_repl_statements.size() - 1) {
TRY(file->write_until_depleted(line));
}
if (i != g_repl_statements.size() - 1) {
TRY(file->write_value('\n'));
}
}
file->close();
return {};
}
static ErrorOr<bool> parse_and_run(JS::Realm& realm, StringView source, StringView source_name)
{
auto& vm = realm.vm();
JS::ThrowCompletionOr<JS::Value> result { JS::js_undefined() };
auto run_script_or_module = [&](auto& script_or_module) {
if (s_dump_ast)
script_or_module->parse_node().dump(0);
result = vm.bytecode_interpreter().run(*script_or_module);
};
if (!s_as_module) {
auto script_or_error = JS::Script::parse(source, realm, source_name);
if (script_or_error.is_error()) {
auto error = script_or_error.error()[0];
auto hint = error.source_location_hint(source);
if (!hint.is_empty())
outln("{}", hint);
auto error_string = TRY(error.to_string());
outln("{}", error_string);
result = vm.throw_completion<JS::SyntaxError>(move(error_string));
} else {
run_script_or_module(script_or_error.value());
}
} else {
auto module_or_error = JS::SourceTextModule::parse(source, realm, source_name);
if (module_or_error.is_error()) {
auto error = module_or_error.error()[0];
auto hint = error.source_location_hint(source);
if (!hint.is_empty())
outln("{}", hint);
auto error_string = TRY(error.to_string());
outln("{}", error_string);
result = vm.throw_completion<JS::SyntaxError>(move(error_string));
} else {
run_script_or_module(module_or_error.value());
}
}
auto handle_exception = [&](JS::Value thrown_value) -> ErrorOr<void> {
warnln("Uncaught exception: ");
TRY(print(thrown_value, PrintTarget::StandardError));
warnln();
if (!thrown_value.is_object() || !is<JS::Error>(thrown_value.as_object()))
return {};
warnln("{}", static_cast<JS::Error const&>(thrown_value.as_object()).stack_string(JS::CompactTraceback::Yes));
return {};
};
if (!result.is_error())
g_last_value = JS::make_handle(result.value());
if (result.is_error()) {
VERIFY(result.throw_completion().value().has_value());
TRY(handle_exception(*result.release_error().value()));
return false;
}
if (s_print_last_result) {
TRY(print(result.value()));
warnln();
}
return true;
}
static JS::ThrowCompletionOr<JS::Value> load_ini_impl(JS::VM& vm)
{
auto& realm = *vm.current_realm();
auto filename = TRY(vm.argument(0).to_byte_string(vm));
auto file_or_error = Core::File::open(filename, Core::File::OpenMode::Read);
if (file_or_error.is_error())
return vm.throw_completion<JS::Error>(TRY_OR_THROW_OOM(vm, String::formatted("Failed to open '{}': {}", filename, file_or_error.error())));
auto config_file = MUST(Core::ConfigFile::open(filename, file_or_error.release_value()));
auto object = JS::Object::create(realm, realm.intrinsics().object_prototype());
for (auto const& group : config_file->groups()) {
auto group_object = JS::Object::create(realm, realm.intrinsics().object_prototype());
for (auto const& key : config_file->keys(group)) {
auto entry = config_file->read_entry(group, key);
group_object->define_direct_property(key, JS::PrimitiveString::create(vm, move(entry)), JS::Attribute::Enumerable | JS::Attribute::Configurable | JS::Attribute::Writable);
}
object->define_direct_property(group, group_object, JS::Attribute::Enumerable | JS::Attribute::Configurable | JS::Attribute::Writable);
}
return object;
}
static JS::ThrowCompletionOr<JS::Value> load_json_impl(JS::VM& vm)
{
auto filename = TRY(vm.argument(0).to_string(vm));
auto file_or_error = Core::File::open(filename, Core::File::OpenMode::Read);
if (file_or_error.is_error())
return vm.throw_completion<JS::Error>(TRY_OR_THROW_OOM(vm, String::formatted("Failed to open '{}': {}", filename, file_or_error.error())));
auto file_contents_or_error = file_or_error.value()->read_until_eof();
if (file_contents_or_error.is_error())
return vm.throw_completion<JS::Error>(TRY_OR_THROW_OOM(vm, String::formatted("Failed to read '{}': {}", filename, file_contents_or_error.error())));
auto json = JsonValue::from_string(file_contents_or_error.value());
if (json.is_error())
return vm.throw_completion<JS::SyntaxError>(JS::ErrorType::JsonMalformed);
return JS::JSONObject::parse_json_value(vm, json.value());
}
void ReplObject::initialize(JS::Realm& realm)
{
Base::initialize(realm);
define_direct_property("global", this, JS::Attribute::Enumerable);
u8 attr = JS::Attribute::Configurable | JS::Attribute::Writable | JS::Attribute::Enumerable;
define_native_function(realm, "exit", exit_interpreter, 0, attr);
define_native_function(realm, "help", repl_help, 0, attr);
define_native_function(realm, "save", save_to_file, 1, attr);
define_native_function(realm, "loadINI", load_ini, 1, attr);
define_native_function(realm, "loadJSON", load_json, 1, attr);
define_native_function(realm, "print", print, 1, attr);
define_native_accessor(
realm,
"_",
[](JS::VM&) {
return g_last_value.value();
},
[](JS::VM& vm) -> JS::ThrowCompletionOr<JS::Value> {
auto& global_object = vm.get_global_object();
VERIFY(is<ReplObject>(global_object));
outln("Disable writing last value to '_'");
// We must delete first otherwise this setter gets called recursively.
TRY(global_object.internal_delete(JS::PropertyKey { "_" }));
auto value = vm.argument(0);
TRY(global_object.internal_set(JS::PropertyKey { "_" }, value, &global_object));
return value;
},
attr);
}
JS_DEFINE_NATIVE_FUNCTION(ReplObject::save_to_file)
{
if (!vm.argument_count())
return JS::Value(false);
auto const save_path = TRY(vm.argument(0).to_string(vm));
if (!write_to_file(save_path).is_error()) {
return JS::Value(true);
}
return JS::Value(false);
}
JS_DEFINE_NATIVE_FUNCTION(ReplObject::exit_interpreter)
{
if (vm.argument_count() != 0)
s_exit_code = TRY(vm.argument(0).to_number(vm)).as_double();
s_keep_running_repl = false;
return JS::js_undefined();
}
JS_DEFINE_NATIVE_FUNCTION(ReplObject::repl_help)
{
warnln("REPL commands:");
warnln(" exit(code): exit the REPL with specified code. Defaults to 0.");
warnln(" help(): display this menu");
warnln(" loadINI(file): load the given file as INI.");
warnln(" loadJSON(file): load the given file as JSON.");
warnln(" print(value): pretty-print the given JS value.");
warnln(" 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_ini)
{
return load_ini_impl(vm);
}
JS_DEFINE_NATIVE_FUNCTION(ReplObject::load_json)
{
return load_json_impl(vm);
}
JS_DEFINE_NATIVE_FUNCTION(ReplObject::print)
{
auto result = ::print(vm.argument(0));
if (result.is_error())
return g_vm->throw_completion<JS::InternalError>(TRY_OR_THROW_OOM(*g_vm, String::formatted("Failed to print value: {}", result.error())));
outln();
return JS::js_undefined();
}
void ScriptObject::initialize(JS::Realm& realm)
{
Base::initialize(realm);
define_direct_property("global", this, JS::Attribute::Enumerable);
u8 attr = JS::Attribute::Configurable | JS::Attribute::Writable | JS::Attribute::Enumerable;
define_native_function(realm, "loadINI", load_ini, 1, attr);
define_native_function(realm, "loadJSON", load_json, 1, attr);
define_native_function(realm, "print", print, 1, attr);
}
JS_DEFINE_NATIVE_FUNCTION(ScriptObject::load_ini)
{
return load_ini_impl(vm);
}
JS_DEFINE_NATIVE_FUNCTION(ScriptObject::load_json)
{
return load_json_impl(vm);
}
JS_DEFINE_NATIVE_FUNCTION(ScriptObject::print)
{
auto result = ::print(vm.argument(0));
if (result.is_error())
return g_vm->throw_completion<JS::InternalError>(TRY_OR_THROW_OOM(*g_vm, String::formatted("Failed to print value: {}", result.error())));
outln();
return JS::js_undefined();
}
static ErrorOr<void> repl(JS::Realm& realm)
{
while (s_keep_running_repl) {
auto const piece = TRY(read_next_piece());
if (Utf8View { piece }.trim(JS::whitespace_characters).is_empty())
continue;
g_repl_statements.append(piece);
TRY(parse_and_run(realm, piece, "REPL"sv));
}
return {};
}
static Function<void()> interrupt_interpreter;
static void sigint_handler()
{
interrupt_interpreter();
}
class ReplConsoleClient final : public JS::ConsoleClient {
public:
ReplConsoleClient(JS::Console& console)
: ConsoleClient(console)
{
}
virtual void clear() override
{
out("\033[3J\033[H\033[2J");
m_group_stack_depth = 0;
fflush(stdout);
}
virtual void end_group() override
{
if (m_group_stack_depth > 0)
m_group_stack_depth--;
}
// 2.3. Printer(logLevel, args[, options]), https://console.spec.whatwg.org/#printer
virtual JS::ThrowCompletionOr<JS::Value> printer(JS::Console::LogLevel log_level, PrinterArguments arguments) override
{
auto indent = TRY_OR_THROW_OOM(*g_vm, String::repeated(' ', m_group_stack_depth * 2));
if (log_level == JS::Console::LogLevel::Trace) {
auto trace = arguments.get<JS::Console::Trace>();
StringBuilder builder;
if (!trace.label.is_empty())
builder.appendff("{}\033[36;1m{}\033[0m\n", indent, trace.label);
for (auto& function_name : trace.stack)
builder.appendff("{}-> {}\n", indent, function_name);
outln("{}", builder.string_view());
return JS::js_undefined();
}
if (log_level == JS::Console::LogLevel::Group || log_level == JS::Console::LogLevel::GroupCollapsed) {
auto group = arguments.get<JS::Console::Group>();
outln("{}\033[36;1m{}\033[0m", indent, group.label);
m_group_stack_depth++;
return JS::js_undefined();
}
auto output = TRY(generically_format_values(arguments.get<JS::MarkedVector<JS::Value>>()));
#ifdef AK_OS_SERENITY
m_console.output_debug_message(log_level, output);
#endif
switch (log_level) {
case JS::Console::LogLevel::Debug:
outln("{}\033[36;1m{}\033[0m", indent, output);
break;
case JS::Console::LogLevel::Error:
case JS::Console::LogLevel::Assert:
outln("{}\033[31;1m{}\033[0m", indent, output);
break;
case JS::Console::LogLevel::Info:
outln("{}(i) {}", indent, output);
break;
case JS::Console::LogLevel::Log:
outln("{}{}", indent, output);
break;
case JS::Console::LogLevel::Warn:
case JS::Console::LogLevel::CountReset:
outln("{}\033[33;1m{}\033[0m", indent, output);
break;
default:
outln("{}{}", indent, output);
break;
}
return JS::js_undefined();
}
private:
int m_group_stack_depth { 0 };
};
ErrorOr<int> serenity_main(Main::Arguments arguments)
{
TRY(Core::System::pledge("stdio rpath wpath cpath tty sigaction map_fixed"));
bool gc_on_every_allocation = false;
bool disable_syntax_highlight = false;
bool disable_debug_printing = false;
bool use_test262_global = false;
StringView evaluate_script;
Vector<StringView> 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(JS::Bytecode::g_dump_bytecode, "Dump the bytecode", "dump-bytecode", 'd');
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(s_strip_ansi, "Disable ANSI colors", "disable-ansi-colors", 'i');
args_parser.add_option(s_disable_source_location_hints, "Disable source location hints", "disable-source-location-hints", 'h');
args_parser.add_option(gc_on_every_allocation, "GC on every allocation", "gc-on-every-allocation", 'g');
args_parser.add_option(disable_syntax_highlight, "Disable live syntax highlighting", "no-syntax-highlight", 's');
args_parser.add_option(disable_debug_printing, "Disable debug output", "disable-debug-output", {});
args_parser.add_option(evaluate_script, "Evaluate argument as a script", "evaluate", 'c', "script");
args_parser.add_option(use_test262_global, "Use test262 global ($262)", "use-test262-global", {});
args_parser.add_positional_argument(script_paths, "Path to script files", "scripts", Core::ArgsParser::Required::No);
args_parser.parse(arguments);
bool syntax_highlight = !disable_syntax_highlight;
AK::set_debug_enabled(!disable_debug_printing);
s_history_path = TRY(String::formatted("{}/.js-history", Core::StandardPaths::home_directory()));
g_vm = TRY(JS::VM::create());
g_vm->set_dynamic_imports_allowed(true);
if (!disable_debug_printing) {
// 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.
g_vm->on_promise_unhandled_rejection = [](auto& promise) {
warn("WARNING: A promise was rejected without any handlers");
warn(" (result: ");
(void)print(promise.result(), PrintTarget::StandardError);
warnln(")");
};
g_vm->on_promise_rejection_handled = [](auto& promise) {
warn("WARNING: A handler was added to an already rejected promise");
warn(" (result: ");
(void)print(promise.result(), PrintTarget::StandardError);
warnln(")");
};
}
// FIXME: Figure out some way to interrupt the interpreter now that vm.exception() is gone.
if (evaluate_script.is_empty() && script_paths.is_empty()) {
s_print_last_result = true;
auto root_execution_context = JS::create_simple_execution_context<ReplObject>(*g_vm);
auto& realm = *root_execution_context->realm;
auto& console_object = *realm.intrinsics().console_object();
ReplConsoleClient console_client(console_object.console());
console_object.console().set_client(console_client);
g_vm->heap().set_should_collect_on_every_allocation(gc_on_every_allocation);
auto& global_environment = realm.global_environment();
s_editor = Line::Editor::construct();
s_editor->load_history(s_history_path.to_byte_string());
signal(SIGINT, [](int) {
if (!s_editor->is_editing())
sigint_handler();
s_editor->save_history(s_history_path.to_byte_string());
});
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.offset();
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).release_value_but_fixme_should_propagate_errors().to_byte_string());
};
auto complete = [&realm, &global_environment](Line::Editor const& editor) -> Vector<Line::CompletionSuggestion> {
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
// - <N>
// where N is part of the name of a variable
// - <N>.<P>
// 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:
// ...<name> <dot>
mode = CompleteNullProperty;
break;
default:
// not a dot, reset back to initial
mode = Initial;
break;
}
break;
case CompleteNullProperty:
if (js_token.is_identifier_name()) {
// ...<name> <dot> <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) {
// ...<name>...
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 = ""sv;
last_token_has_trivia = false; // <name> <dot> [tab] is sensible to complete.
}
if (mode == Initial || last_token_has_trivia)
return {}; // we do not know how to complete this
Vector<Line::CompletionSuggestion> results;
Function<void(JS::Shape const&, StringView)> 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(ByteString(key));
results.last().invariant_offset = property_pattern.length();
}
}
}
if (auto const* prototype = shape.prototype()) {
list_all_properties(prototype->shape(), property_pattern);
}
};
switch (mode) {
case CompleteProperty: {
auto reference_or_error = g_vm->resolve_binding(variable_name, &global_environment);
if (reference_or_error.is_error())
return {};
auto value_or_error = reference_or_error.value().get_value(*g_vm);
if (value_or_error.is_error())
return {};
auto variable = value_or_error.value();
VERIFY(!variable.is_empty());
if (!variable.is_object())
break;
auto const object = MUST(variable.to_object(*g_vm));
auto const& shape = object->shape();
list_all_properties(shape, property_name);
break;
}
case CompleteVariable: {
auto const& variable = realm.global_object();
list_all_properties(variable.shape(), variable_name);
for (auto const& name : global_environment.declarative_record().bindings()) {
if (name.starts_with(variable_name)) {
results.empend(name);
results.last().invariant_offset = variable_name.length();
}
}
break;
}
default:
VERIFY_NOT_REACHED();
}
return results;
};
s_editor->on_tab_complete = move(complete);
TRY(repl(realm));
s_editor->save_history(s_history_path.to_byte_string());
} else {
OwnPtr<JS::ExecutionContext> root_execution_context;
if (use_test262_global)
root_execution_context = JS::create_simple_execution_context<JS::Test262::GlobalObject>(*g_vm);
else
root_execution_context = JS::create_simple_execution_context<ScriptObject>(*g_vm);
auto& realm = *root_execution_context->realm;
auto& console_object = *realm.intrinsics().console_object();
ReplConsoleClient console_client(console_object.console());
console_object.console().set_client(console_client);
g_vm->heap().set_should_collect_on_every_allocation(gc_on_every_allocation);
signal(SIGINT, [](int) {
sigint_handler();
});
StringBuilder builder;
StringView source_name;
if (evaluate_script.is_empty()) {
if (script_paths.size() > 1)
warnln("Warning: Multiple files supplied, this will concatenate the sources and resolve modules as if it was the first file");
for (auto& path : script_paths) {
auto file = TRY(Core::File::open(path, Core::File::OpenMode::Read));
auto file_contents = TRY(file->read_until_eof());
auto source = StringView { file_contents };
if (Utf8View { file_contents }.validate()) {
builder.append(source);
} else {
auto decoder = TextCodec::decoder_for("windows-1252"sv);
VERIFY(decoder.has_value());
auto utf8_source = TRY(TextCodec::convert_input_to_utf8_using_given_decoder_unless_there_is_a_byte_order_mark(*decoder, source));
builder.append(utf8_source);
}
}
source_name = script_paths[0];
} else {
builder.append(evaluate_script);
source_name = "eval"sv;
}
// We resolve modules as if it is the first file
if (!TRY(parse_and_run(realm, builder.string_view(), source_name)))
return 1;
}
return s_exit_code;
}