ladybird/Libraries/LibJS/Runtime/Map.cpp

/*
 * Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <LibJS/Runtime/Map.h>

namespace JS {

GC_DEFINE_ALLOCATOR(Map);

GC::Ref<Map> Map::create(Realm& realm)
{
    return realm.create<Map>(realm.intrinsics().map_prototype());
}

Map::Map(Object& prototype)
    : Object(ConstructWithPrototypeTag::Tag, prototype)
{
}

// 24.1.3.1 Map.prototype.clear ( ), https://tc39.es/ecma262/#sec-map.prototype.clear
void Map::map_clear()
{
    m_keys.clear();
    m_entries.clear();
}

// 24.1.3.3 Map.prototype.delete ( key ), https://tc39.es/ecma262/#sec-map.prototype.delete
bool Map::map_remove(Value const& key)
{
    Optional<size_t> index;

    for (auto it = m_keys.begin(); !it.is_end(); ++it) {
        if (ValueTraits::equals(*it, key)) {
            index = it.key();
            break;
        }
    }

    if (!index.has_value())
        return false;

    m_keys.remove(*index);
    m_entries.remove(key);
    return true;
}

// 24.1.3.6 Map.prototype.get ( key ), https://tc39.es/ecma262/#sec-map.prototype.get
Optional<Value> Map::map_get(Value const& key) const
{
    if (auto it = m_entries.find(key); it != m_entries.end())
        return it->value;
    return {};
}

// 24.1.3.7 Map.prototype.has ( key ), https://tc39.es/ecma262/#sec-map.prototype.has
bool Map::map_has(Value const& key) const
{
    return m_entries.contains(key);
}

// 24.1.3.9 Map.prototype.set ( key, value ), https://tc39.es/ecma262/#sec-map.prototype.set
void Map::map_set(Value const& key, Value value)
{
    auto it = m_entries.find(key);
    if (it != m_entries.end()) {
        it->value = value;
    } else {
        auto index = m_next_insertion_id++;
        m_keys.insert(index, key);
        m_entries.set(key, value);
    }
}

size_t Map::map_size() const
{
    return m_keys.size();
}

void Map::visit_edges(Cell::Visitor& visitor)
{
    Base::visit_edges(visitor);
    for (auto& value : m_entries) {
        visitor.visit(value.key);
        visitor.visit(value.value);
    }
    // NOTE: The entries in m_keys are already visited by the walk over m_entries above.
    visitor.ignore(m_keys);
}

}