ladybird/AK/Utf16String.h
Andreas Kling 24934ba479 LibJS: Make single-character ASCII string cache strings be Utf16String
Just another little step towards all strings being Utf16String.
2025-10-05 16:39:14 +02:00

345 lines
10 KiB
C++

/*
* Copyright (c) 2025, Tim Flynn <trflynn89@ladybird.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Badge.h>
#include <AK/Error.h>
#include <AK/Format.h>
#include <AK/NonnullRefPtr.h>
#include <AK/String.h>
#include <AK/StringView.h>
#include <AK/Traits.h>
#include <AK/UnicodeUtils.h>
#include <AK/Utf16StringBase.h>
#include <AK/Utf16StringData.h>
#include <AK/Utf16View.h>
#include <AK/Utf8View.h>
namespace AK {
// Utf16String is a strongly owned sequence of Unicode code points encoded as UTF-16.
//
// The data may or may not be heap-allocated, and may or may not be reference counted. As a memory optimization, if the
// UTF-16 string is entirely ASCII, the string is stored as 8-bit bytes.
class [[nodiscard]] Utf16String : public Detail::Utf16StringBase {
public:
using Utf16StringBase::Utf16StringBase;
explicit constexpr Utf16String(Utf16StringBase&& base)
: Utf16StringBase(move(base))
{
}
ALWAYS_INLINE static Utf16String from_utf8(StringView utf8_string)
{
VERIFY(Utf8View { utf8_string }.validate());
return from_utf8_without_validation(utf8_string);
}
ALWAYS_INLINE static Utf16String from_utf8(String const& utf8_string)
{
return from_utf8_without_validation(utf8_string);
}
ALWAYS_INLINE static Utf16String from_utf8(FlyString const& utf8_string)
{
return from_utf8_without_validation(utf8_string);
}
enum class WithBOMHandling {
No,
Yes,
};
static Utf16String from_utf8_with_replacement_character(StringView, WithBOMHandling = WithBOMHandling::Yes);
ALWAYS_INLINE static ErrorOr<Utf16String> try_from_utf8(StringView utf8_string)
{
if (!Utf8View { utf8_string }.validate())
return Error::from_string_literal("Input was not valid UTF-8");
return from_utf8_without_validation(utf8_string);
}
static Utf16String from_utf8_without_validation(StringView);
static Utf16String from_ascii_without_validation(ReadonlyBytes);
static Utf16String from_utf16(Utf16View const& utf16_string);
template<typename T>
requires(IsOneOf<RemoveCVReference<T>, Utf16String, Utf16FlyString>)
static Utf16String from_utf16(T&&) = delete;
static Utf16String from_utf32(Utf32View const&);
ALWAYS_INLINE static constexpr Utf16String from_ascii_character(u8 character)
{
auto short_string = Detail::ShortString::create_with_byte_count(1);
short_string.storage[0] = character;
return Utf16String { short_string };
}
ALWAYS_INLINE static Utf16String from_code_point(u32 code_point)
{
Array<char16_t, 2> code_units;
size_t length_in_code_units = 0;
(void)UnicodeUtils::code_point_to_utf16(code_point, [&](auto code_unit) {
code_units[length_in_code_units++] = code_unit;
});
return from_utf16({ code_units.data(), length_in_code_units });
}
template<typename... Parameters>
ALWAYS_INLINE static Utf16String formatted(CheckedFormatString<Parameters...>&& format, Parameters const&... parameters)
{
StringBuilder builder(StringBuilder::Mode::UTF16);
VariadicFormatParams<AllowDebugOnlyFormatters::No, Parameters...> variadic_format_parameters { parameters... };
MUST(vformat(builder, format.view(), variadic_format_parameters));
return builder.to_utf16_string();
}
template<Integral T>
[[nodiscard]] static Utf16String number(T);
template<FloatingPoint T>
[[nodiscard]] static Utf16String number(T value)
{
return formatted("{}", value);
}
template<class SeparatorType, class CollectionType>
ALWAYS_INLINE static Utf16String join(SeparatorType const& separator, CollectionType const& collection, StringView format = "{}"sv)
{
StringBuilder builder(StringBuilder::Mode::UTF16);
builder.join(separator, collection, format);
return builder.to_utf16_string();
}
static Utf16String repeated(u32 code_point, size_t count);
Utf16String to_well_formed() const;
String to_well_formed_utf8() const;
// These methods require linking LibUnicode.
Utf16String to_lowercase(Optional<StringView> const& locale = {}) const;
Utf16String to_uppercase(Optional<StringView> const& locale = {}) const;
Utf16String to_titlecase(Optional<StringView> const& locale = {}, TrailingCodePointTransformation trailing_code_point_transformation = TrailingCodePointTransformation::Lowercase) const;
Utf16String to_casefold() const;
Utf16String to_fullwidth() const;
ALWAYS_INLINE Utf16String to_ascii_lowercase() const
{
auto view = utf16_view();
if (view.has_ascii_storage()) {
if (!any_of(view.ascii_span(), is_ascii_upper_alpha))
return *this;
} else {
if (!any_of(view.utf16_span(), is_ascii_upper_alpha))
return *this;
}
return view.to_ascii_lowercase();
}
ALWAYS_INLINE Utf16String to_ascii_uppercase() const
{
auto view = utf16_view();
if (view.has_ascii_storage()) {
if (!any_of(view.ascii_span(), is_ascii_lower_alpha))
return *this;
} else {
if (!any_of(view.utf16_span(), is_ascii_lower_alpha))
return *this;
}
return view.to_ascii_uppercase();
}
ALWAYS_INLINE Utf16String to_ascii_titlecase() const
{
return utf16_view().to_ascii_titlecase();
}
ALWAYS_INLINE Utf16String replace(char16_t needle, Utf16View const& replacement, ReplaceMode replace_mode) const
{
auto view = utf16_view();
if (view.is_empty() || !view.contains(needle))
return *this;
return view.replace(needle, replacement, replace_mode);
}
ALWAYS_INLINE Utf16String replace(Utf16View const& needle, Utf16View const& replacement, ReplaceMode replace_mode) const
{
auto view = utf16_view();
if (view.is_empty() || !view.contains(needle))
return *this;
return view.replace(needle, replacement, replace_mode);
}
ALWAYS_INLINE Utf16String trim(Utf16View const& code_units, TrimMode mode = TrimMode::Both) const
{
if (is_empty())
return {};
bool needs_trimming = false;
if (mode == TrimMode::Left || mode == TrimMode::Both)
needs_trimming |= code_units.contains(code_unit_at(0));
if (mode == TrimMode::Right || mode == TrimMode::Both)
needs_trimming |= code_units.contains(code_unit_at(length_in_code_units() - 1));
if (!needs_trimming)
return *this;
return Utf16String::from_utf16(utf16_view().trim(code_units, mode));
}
ALWAYS_INLINE Utf16String trim_ascii_whitespace(TrimMode mode = TrimMode::Both) const
{
return trim(" \n\t\v\f\r"sv, mode);
}
ALWAYS_INLINE Utf16String escape_html_entities() const { return utf16_view().escape_html_entities(); }
static Utf16String from_string_builder(Badge<StringBuilder>, StringBuilder& builder);
static ErrorOr<Utf16String> from_ipc_stream(Stream&, size_t length_in_code_units, bool is_ascii);
constexpr Utf16String(Badge<Optional<Utf16String>>, nullptr_t)
: Detail::Utf16StringBase(Badge<Utf16String> {}, nullptr)
{
}
[[nodiscard]] constexpr bool is_invalid(Badge<Optional<Utf16String>>) const { return raw() == 0; }
private:
ALWAYS_INLINE explicit Utf16String(NonnullRefPtr<Detail::Utf16StringData const> value)
: Utf16StringBase(move(value))
{
}
};
template<>
class [[nodiscard]] Optional<Utf16String> : public OptionalBase<Utf16String> {
template<typename U>
friend class Optional;
public:
using ValueType = Utf16String;
constexpr Optional() = default;
template<SameAs<OptionalNone> V>
constexpr Optional(V) { }
constexpr Optional(Optional<Utf16String> const& other)
: m_value(other.m_value)
{
}
constexpr Optional(Optional&& other)
: m_value(move(other.m_value))
{
}
template<typename U = Utf16String>
requires(!IsSame<OptionalNone, RemoveCVReference<U>>)
explicit(!IsConvertible<U&&, Utf16String>) constexpr Optional(U&& value)
requires(!IsSame<RemoveCVReference<U>, Optional<Utf16String>> && IsConstructible<Utf16String, U &&>)
: m_value(forward<U>(value))
{
}
template<SameAs<OptionalNone> V>
constexpr Optional& operator=(V)
{
clear();
return *this;
}
constexpr Optional& operator=(Optional const& other)
{
if (this != &other)
m_value = other.m_value;
return *this;
}
constexpr Optional& operator=(Optional&& other)
{
if (this != &other)
m_value = move(other.m_value);
return *this;
}
constexpr void clear()
{
m_value = empty_value;
}
[[nodiscard]] constexpr bool has_value() const
{
return !m_value.is_invalid({});
}
[[nodiscard]] constexpr Utf16String& value() &
{
VERIFY(has_value());
return m_value;
}
[[nodiscard]] constexpr Utf16String const& value() const&
{
VERIFY(has_value());
return m_value;
}
[[nodiscard]] constexpr Utf16String value() &&
{
return release_value();
}
[[nodiscard]] constexpr Utf16String release_value()
{
VERIFY(has_value());
return exchange(m_value, empty_value);
}
private:
static constexpr Utf16String empty_value { Badge<Optional<Utf16String>> {}, nullptr };
Utf16String m_value { empty_value };
};
template<>
struct Formatter<Utf16String> : Formatter<FormatString> {
ErrorOr<void> format(FormatBuilder&, Utf16String const&);
};
template<>
struct Traits<Utf16String> : public DefaultTraits<Utf16String> {
static unsigned hash(Utf16String const& s) { return s.hash(); }
};
}
[[nodiscard]] ALWAYS_INLINE AK::Utf16String operator""_utf16(char const* string, size_t length)
{
AK::StringView view { string, length };
ASSERT(AK::Utf8View { view }.validate());
return AK::Utf16String::from_utf8_without_validation(view);
}
[[nodiscard]] ALWAYS_INLINE AK::Utf16String operator""_utf16(char16_t const* string, size_t length)
{
return AK::Utf16String::from_utf16({ string, length });
}