LibUncode: Parse and generate emoji code point data

According to TR #51, the "best definition of the full set [of emojis] is
in the emoji-test.txt file". This defines not only the emoji themselves,
but the order in which they should be displayed, and what "group" of
emojis they belong to.

Userland/Libraries/LibUnicode/Emoji.h

@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2022, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Optional.h>
+#include <AK/StringView.h>
+#include <AK/Types.h>
+
+namespace Unicode {
+
+enum class EmojiGroup : u8 {
+    SmileysAndEmotion,
+    PeopleAndBody,
+    Component,
+    AnimalsAndNature,
+    FoodAndDrink,
+    TravelAndPlaces,
+    Activities,
+    Objects,
+    Symbols,
+    Flags,
+};
+
+struct Emoji {
+    StringView name;
+    EmojiGroup group;
+    u32 display_order { 0 };
+    Span<u32 const> code_points;
+};
+
+Optional<Emoji> find_emoji_for_code_points(Span<u32 const> code_points);
+
+template<size_t Size>
+Optional<Emoji> find_emoji_for_code_points(u32 const (&code_points)[Size])
+{
+    return find_emoji_for_code_points(Span<u32 const> { code_points });
+}
+
+constexpr StringView emoji_group_to_string(EmojiGroup group)
+{
+    switch (group) {
+    case EmojiGroup::SmileysAndEmotion:
+        return "Smileys & Emotion"sv;
+    case EmojiGroup::PeopleAndBody:
+        return "People & Body"sv;
+    case EmojiGroup::Component:
+        return "Component"sv;
+    case EmojiGroup::AnimalsAndNature:
+        return "Animals & Nature"sv;
+    case EmojiGroup::FoodAndDrink:
+        return "Food & Drink"sv;
+    case EmojiGroup::TravelAndPlaces:
+        return "Travel & Places"sv;
+    case EmojiGroup::Activities:
+        return "Activities"sv;
+    case EmojiGroup::Objects:
+        return "Objects"sv;
+    case EmojiGroup::Symbols:
+        return "Symbols"sv;
+    case EmojiGroup::Flags:
+        return "Flags"sv;
+    }
+
+    VERIFY_NOT_REACHED();
+}
+
+constexpr EmojiGroup emoji_group_from_string(StringView group)
+{
+    if (group == "Smileys & Emotion"sv)
+        return EmojiGroup::SmileysAndEmotion;
+    if (group == "People & Body"sv)
+        return EmojiGroup::PeopleAndBody;
+    if (group == "Component"sv)
+        return EmojiGroup::Component;
+    if (group == "Animals & Nature"sv)
+        return EmojiGroup::AnimalsAndNature;
+    if (group == "Food & Drink"sv)
+        return EmojiGroup::FoodAndDrink;
+    if (group == "Travel & Places"sv)
+        return EmojiGroup::TravelAndPlaces;
+    if (group == "Activities"sv)
+        return EmojiGroup::Activities;
+    if (group == "Objects"sv)
+        return EmojiGroup::Objects;
+    if (group == "Symbols"sv)
+        return EmojiGroup::Symbols;
+    if (group == "Flags"sv)
+        return EmojiGroup::Flags;
+
+    VERIFY_NOT_REACHED();
+}
+
+}