AK: Add a basic formatter for wchar_t

Author: https://github.com/timschumi
Commit: 67a579aab0
Pull-request: https://github.com/SerenityOS/serenity/pull/10170
Reviewed-by: https://github.com/BertalanD ✅
Reviewed-by: https://github.com/Hendiadyoin1
Reviewed-by: https://github.com/IdanHo
Reviewed-by: https://github.com/kleinesfilmroellchen

AK/Format.cpp

@@ -688,6 +688,19 @@ void Formatter<char>::format(FormatBuilder& builder, char value)
         return formatter.format(builder, { &value, 1 });
     }
 }
+void Formatter<wchar_t>::format(FormatBuilder& builder, wchar_t value)
+{
+    if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {
+        Formatter<u32> formatter { *this };
+        return formatter.format(builder, static_cast<u32>(value));
+    } else {
+        StringBuilder codepoint;
+        codepoint.append_code_point(value);
+
+        Formatter<StringView> formatter { *this };
+        return formatter.format(builder, codepoint.to_string());
+    }
+}
 void Formatter<bool>::format(FormatBuilder& builder, bool value)
 {
     if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {