ladybird/Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp
Timothy Flynn b6ff7f4fcc LibJS: Allow PrimitiveString to be created with a UTF-16 string
PrimitiveString may currently only be created with a UTF-8 string, and
it transcodes on the fly when a UTF-16 string is needed. Allow creating
a PrimitiveString from a UTF-16 string to avoid unnecessary transcoding
when the caller only wants UTF-16.
2021-08-04 11:18:24 +02:00

113 lines
2.7 KiB
C++

/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/CharacterTypes.h>
#include <AK/Utf16View.h>
#include <LibJS/Runtime/PrimitiveString.h>
#include <LibJS/Runtime/VM.h>
namespace JS {
PrimitiveString::PrimitiveString(String string)
: m_utf8_string(move(string))
, m_has_utf8_string(true)
{
}
PrimitiveString::PrimitiveString(Vector<u16> string)
: m_utf16_string(move(string))
, m_has_utf16_string(true)
{
}
PrimitiveString::~PrimitiveString()
{
}
String const& PrimitiveString::string() const
{
if (!m_has_utf8_string) {
m_utf8_string = utf16_string_view().to_utf8(Utf16View::AllowInvalidCodeUnits::Yes);
m_has_utf8_string = true;
}
return m_utf8_string;
}
Vector<u16> const& PrimitiveString::utf16_string() const
{
if (!m_has_utf16_string) {
m_utf16_string = AK::utf8_to_utf16(m_utf8_string);
m_has_utf16_string = true;
}
return m_utf16_string;
}
Utf16View PrimitiveString::utf16_string_view() const
{
return Utf16View { utf16_string() };
}
PrimitiveString* js_string(Heap& heap, Utf16View const& view)
{
if (view.is_empty())
return &heap.vm().empty_string();
if (view.length_in_code_units() == 1) {
u16 code_unit = view.code_unit_at(0);
if (is_ascii(code_unit))
return &heap.vm().single_ascii_character_string(static_cast<u8>(code_unit));
}
Vector<u16> string;
string.ensure_capacity(view.length_in_code_units());
string.append(view.data(), view.length_in_code_units());
return js_string(heap, move(string));
}
PrimitiveString* js_string(VM& vm, Utf16View const& view)
{
return js_string(vm.heap(), view);
}
PrimitiveString* js_string(Heap& heap, Vector<u16> string)
{
if (string.is_empty())
return &heap.vm().empty_string();
if (string.size() == 1) {
u16 code_unit = string.at(0);
if (is_ascii(code_unit))
return &heap.vm().single_ascii_character_string(static_cast<u8>(code_unit));
}
return heap.allocate_without_global_object<PrimitiveString>(move(string));
}
PrimitiveString* js_string(VM& vm, Vector<u16> string)
{
return js_string(vm.heap(), move(string));
}
PrimitiveString* js_string(Heap& heap, String string)
{
if (string.is_empty())
return &heap.vm().empty_string();
if (string.length() == 1) {
auto ch = static_cast<u8>(string.characters()[0]);
if (is_ascii(ch))
return &heap.vm().single_ascii_character_string(ch);
}
return heap.allocate_without_global_object<PrimitiveString>(move(string));
}
PrimitiveString* js_string(VM& vm, String string)
{
return js_string(vm.heap(), move(string));
}
}