mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2024-09-20 09:49:15 +03:00
f8a0365002
This was preventing some unqualified emoji sequences from rendering
properly, such as the custom SerenityOS flag. We rendered the flag
correctly when given the fully qualified sequence:
U+1F3F3 U+FEOF U+200D U+1F41E
But were not detecting the unqualified sequence as an emoji when also
filtering for emoji-presentation sequences:
U+1F3F3 U+200D U+1F41E
127 lines
4.5 KiB
C++
127 lines
4.5 KiB
C++
/*
|
|
* Copyright (c) 2022-2023, Tim Flynn <trflynn89@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <AK/CharacterTypes.h>
|
|
#include <AK/Utf32View.h>
|
|
#include <AK/Utf8View.h>
|
|
#include <LibUnicode/CharacterTypes.h>
|
|
#include <LibUnicode/Emoji.h>
|
|
|
|
#if ENABLE_UNICODE_DATA
|
|
# include <LibUnicode/UnicodeData.h>
|
|
#endif
|
|
|
|
namespace Unicode {
|
|
|
|
Optional<Emoji> __attribute__((weak)) find_emoji_for_code_points(ReadonlySpan<u32>) { return {}; }
|
|
|
|
#if ENABLE_UNICODE_DATA
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_core_sequence
|
|
static bool could_be_start_of_emoji_core_sequence(u32 code_point, Optional<u32> const& next_code_point, SequenceType type)
|
|
{
|
|
// emoji_core_sequence := emoji_character | emoji_presentation_sequence | emoji_keycap_sequence | emoji_modifier_sequence | emoji_flag_sequence
|
|
|
|
static constexpr auto emoji_presentation_selector = 0xFE0Fu;
|
|
static constexpr auto combining_enclosing_keycap = 0x20E3u;
|
|
static constexpr auto zero_width_joiner = 0x200Du;
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_keycap_sequence
|
|
// emoji_keycap_sequence := [0-9#*] \x{FE0F 20E3}
|
|
if (is_ascii_digit(code_point) || code_point == '#' || code_point == '*')
|
|
return next_code_point == emoji_presentation_selector || next_code_point == combining_enclosing_keycap;
|
|
|
|
// A little non-standard, but all other ASCII code points are not the beginning of any emoji sequence.
|
|
if (is_ascii(code_point))
|
|
return false;
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_character
|
|
switch (type) {
|
|
case SequenceType::Any:
|
|
if (code_point_has_property(code_point, Property::Emoji))
|
|
return true;
|
|
break;
|
|
case SequenceType::EmojiPresentation:
|
|
if (code_point_has_property(code_point, Property::Emoji_Presentation))
|
|
return true;
|
|
if (next_code_point == zero_width_joiner && code_point_has_property(code_point, Property::Emoji))
|
|
return true;
|
|
break;
|
|
}
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_presentation_sequence
|
|
// emoji_presentation_sequence := emoji_character emoji_presentation_selector
|
|
if (next_code_point == emoji_presentation_selector)
|
|
return true;
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_modifier_sequence
|
|
// emoji_modifier_sequence := emoji_modifier_base emoji_modifier
|
|
if (code_point_has_property(code_point, Property::Emoji_Modifier_Base))
|
|
return true;
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_flag_sequence
|
|
// emoji_flag_sequence := regional_indicator regional_indicator
|
|
if (code_point_has_property(code_point, Property::Regional_Indicator))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool could_be_start_of_serenity_emoji(u32 code_point)
|
|
{
|
|
// We use Supplementary Private Use Area-B for custom Serenity emoji, starting at U+10CD00.
|
|
static constexpr auto first_custom_serenity_emoji_code_point = 0x10CD00u;
|
|
|
|
return code_point >= first_custom_serenity_emoji_code_point;
|
|
}
|
|
|
|
#endif
|
|
|
|
// https://unicode.org/reports/tr51/#def_emoji_sequence
|
|
template<typename CodePointIterator>
|
|
static bool could_be_start_of_emoji_sequence_impl(CodePointIterator const& it, [[maybe_unused]] SequenceType type)
|
|
{
|
|
// emoji_sequence := emoji_core_sequence | emoji_zwj_sequence | emoji_tag_sequence
|
|
|
|
if (it.done())
|
|
return false;
|
|
|
|
#if ENABLE_UNICODE_DATA
|
|
// The purpose of this method is to quickly filter out code points that cannot be the start of
|
|
// an emoji. The emoji_core_sequence definition alone captures the start of all possible
|
|
// emoji_zwj_sequence and emoji_tag_sequence emojis, because:
|
|
//
|
|
// * emoji_zwj_sequence must begin with emoji_zwj_element, which is:
|
|
// emoji_zwj_element := emoji_core_sequence | emoji_tag_sequence
|
|
//
|
|
// * emoji_tag_sequence must begin with tag_base, which is:
|
|
// tag_base := emoji_character | emoji_modifier_sequence | emoji_presentation_sequence
|
|
// Note that this is a subset of emoji_core_sequence.
|
|
auto code_point = *it;
|
|
auto next_code_point = it.peek(1);
|
|
|
|
if (could_be_start_of_emoji_core_sequence(code_point, next_code_point, type))
|
|
return true;
|
|
if (could_be_start_of_serenity_emoji(code_point))
|
|
return true;
|
|
return false;
|
|
#else
|
|
return true;
|
|
#endif
|
|
}
|
|
|
|
bool could_be_start_of_emoji_sequence(Utf8CodePointIterator const& it, SequenceType type)
|
|
{
|
|
return could_be_start_of_emoji_sequence_impl(it, type);
|
|
}
|
|
|
|
bool could_be_start_of_emoji_sequence(Utf32CodePointIterator const& it, SequenceType type)
|
|
{
|
|
return could_be_start_of_emoji_sequence_impl(it, type);
|
|
}
|
|
|
|
}
|