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/*
* Copyright (c) 2020, Matthew Olsson <mattco@serenityos.org>
* Copyright (c) 2022-2023, Linus Groh <linusg@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/GlobalObject.h>
#include <LibJS/Runtime/SymbolConstructor.h>
namespace JS {
SymbolConstructor::SymbolConstructor(Realm& realm)
: NativeFunction(realm.vm().names.Symbol.as_string(), *realm.intrinsics().function_prototype())
{
}
ThrowCompletionOr<void> SymbolConstructor::initialize(Realm& realm)
{
auto& vm = this->vm();
MUST_OR_THROW_OOM(NativeFunction::initialize(realm));
// 20.4.2.9 Symbol.prototype, https://tc39.es/ecma262/#sec-symbol.prototype
define_direct_property(vm.names.prototype, realm.intrinsics().symbol_prototype(), 0);
u8 attr = Attribute::Writable | Attribute::Configurable;
define_native_function(realm, vm.names.for_, for_, 1, attr);
define_native_function(realm, vm.names.keyFor, key_for, 1, attr);
#define __JS_ENUMERATE(SymbolName, snake_name) \
define_direct_property(vm.names.SymbolName, vm.well_known_symbol_##snake_name(), 0);
JS_ENUMERATE_WELL_KNOWN_SYMBOLS
#undef __JS_ENUMERATE
define_direct_property(vm.names.length, Value(0), Attribute::Configurable);
return {};
}
// 20.4.1.1 Symbol ( [ description ] ), https://tc39.es/ecma262/#sec-symbol-description
ThrowCompletionOr<Value> SymbolConstructor::call()
{
auto& vm = this->vm();
auto description = vm.argument(0);
// 2. If description is undefined, let descString be undefined.
// 3. Else, let descString be ? ToString(description).
auto description_string = description.is_undefined()
? Optional<String> {}
: TRY(description.to_string(vm));
// 4. Return a new Symbol whose [[Description]] is descString.
return Symbol::create(vm, move(description_string), false);
}
// 20.4.1.1 Symbol ( [ description ] ), https://tc39.es/ecma262/#sec-symbol-description
ThrowCompletionOr<NonnullGCPtr<Object>> SymbolConstructor::construct(FunctionObject&)
{
// 1. If NewTarget is not undefined, throw a TypeError exception.
return vm().throw_completion<TypeError>(ErrorType::NotAConstructor, "Symbol");
}
// 20.4.2.2 Symbol.for ( key ), https://tc39.es/ecma262/#sec-symbol.for
JS_DEFINE_NATIVE_FUNCTION(SymbolConstructor::for_)
{
// 1. Let stringKey be ? ToString(key).
auto string_key = TRY(vm.argument(0).to_string(vm));
// 2. For each element e of the GlobalSymbolRegistry List, do
auto result = vm.global_symbol_registry().get(string_key);
if (result.has_value()) {
// a. If SameValue(e.[[Key]], stringKey) is true, return e.[[Symbol]].
return result.value();
}
// 3. Assert: GlobalSymbolRegistry does not currently contain an entry for stringKey.
VERIFY(!result.has_value());
// 4. Let newSymbol be a new unique Symbol value whose [[Description]] value is stringKey.
auto new_symbol = Symbol::create(vm, string_key, true);
// 5. Append the Record { [[Key]]: stringKey, [[Symbol]]: newSymbol } to the GlobalSymbolRegistry List.
vm.global_symbol_registry().set(string_key, new_symbol);
// 6. Return newSymbol.
return new_symbol;
}
// 20.4.2.6 Symbol.keyFor ( sym ), https://tc39.es/ecma262/#sec-symbol.keyfor
JS_DEFINE_NATIVE_FUNCTION(SymbolConstructor::key_for)
{
auto argument = vm.argument(0);
// 1. If sym is not a Symbol, throw a TypeError exception.
if (!argument.is_symbol())
return vm.throw_completion<TypeError>(ErrorType::NotASymbol, TRY_OR_THROW_OOM(vm, argument.to_string_without_side_effects()));
// 2. Return KeyForSymbol(sym).
auto key = argument.as_symbol().key();
return key.has_value()
? PrimitiveString::create(vm, key.release_value())
: js_undefined();
}
}
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