feat: std::format support for dpp::snowflake (#1203)

Author: braindigitalis

CMakeLists.txt

@@ -25,6 +25,7 @@ option(DPP_INSTALL "Generate the install target" ON)
 option(DPP_BUILD_TEST "Build the test program" ON)
 option(DPP_NO_VCPKG "No VCPKG" OFF)
 option(DPP_CORO "Experimental support for C++20 coroutines" OFF)
+option(DPP_FORMATTERS "Support for C++20 formatters" OFF)
 option(DPP_USE_EXTERNAL_JSON "Use an external installation of nlohmann::json" OFF)
 option(DPP_USE_PCH "Use precompiled headers to speed up compilation" OFF)
 option(AVX_TYPE "Force AVX type for speeding up audio mixing" OFF)

include/dpp/snowflake.h

@@ -26,6 +26,10 @@
 #include <cstdint>
 #include <type_traits>
 
+#ifdef DPP_FORMATTERS
+#include <format>
+#endif
+
 /**
  * @brief The main namespace for D++ functions. classes and types
  */
@@ -281,3 +285,23 @@ struct std::hash<dpp::snowflake>
 		return std::hash<uint64_t>{}(s.value);
 	}
 };
+
+#ifdef DPP_FORMATTERS
+/*
+ * @brief implementation of formater for dpp::snowflake for std::format support
+ * https://en.cppreference.com/w/cpp/utility/format/formatter
+ */
+template <>
+struct std::formatter<dpp::snowflake>
+{
+        template<class TP>
+        constexpr typename TP::iterator parse(TP& ctx) {
+                return ctx.begin();
+        }
+
+        template<class TF>
+        typename TF::iterator format(const dpp::snowflake& snowflake, TF& ctx) const {
+                return std::format_to(ctx.out(), "{}", snowflake.str());
+        }
+};
+#endif //DPP_FORMATTERS

library/CMakeLists.txt

@@ -341,6 +341,10 @@ if(DPP_CORO)
 					COMMAND php buildtools/make_struct.php "\\Dpp\\Generator\\CoroGenerator")
 endif()
 
+if(DPP_FORMATTERS)
+	target_compile_definitions(dpp PUBLIC DPP_FORMATTERS)
+endif()
+
 if (DPP_BUILD_TEST)
 	enable_testing(${CMAKE_CURRENT_SOURCE_DIR}/..)
 	file(GLOB testnamelist "${CMAKE_CURRENT_SOURCE_DIR}/../src/*")
@@ -351,7 +355,7 @@ if (DPP_BUILD_TEST)
 			set (testsrc "")
 			file(GLOB testsrc "${modules_dir}/${testname}/*.cpp")
 			add_executable(${testname} ${testsrc})
-			if (DPP_CORO)
+			if (DPP_CORO OR DPP_FORMATTERS)
 				target_compile_features(${testname} PRIVATE cxx_std_20)
 			else()
 				target_compile_features(${testname} PRIVATE cxx_std_17)

src/unittest/test.cpp

@@ -379,6 +379,19 @@ Markdown lol \\|\\|spoiler\\|\\| \\~\\~strikethrough\\~\\~ \\`small \\*code\\* b
 		set_test(SNOWFLAKE, success);
 	}
 
+        { // test snowflake: std::format support
+
+                #ifdef DPP_FORMATTERS
+                        set_test(SNOWFLAKE_STD_FORMAT,
+                            std::format("{}",dpp::snowflake{}) == "0" &&
+                            std::format("{}",dpp::snowflake{12345}) == "12345" &&
+                            std::format("{} hello {}", dpp::snowflake{12345}, dpp::snowflake{54321}) == "12345 hello 54321"
+                        );
+                #else
+                        set_status(SNOWFLAKE_STD_FORMAT,ts_skipped);
+                #endif // DPP_FORMATTERS
+        };
+
 	{ // test dpp::json_interface
 		start_test(JSON_INTERFACE);
 		struct fillable : dpp::json_interface<fillable> {
@@ -776,7 +789,7 @@ Markdown lol \\|\\|spoiler\\|\\| \\~\\~strikethrough\\~\\~ \\`small \\*code\\* b
 				 m5.get_url() == "" &&
 				 m6.get_url() == "" &&
 				 m7.get_url() == "" &&
-				 m8.get_url() == "" 
+				 m8.get_url() == ""
 		);
 	}
 
@@ -886,31 +899,31 @@ Markdown lol \\|\\|spoiler\\|\\| \\~\\~strikethrough\\~\\~ \\`small \\*code\\* b
 
 		set_test(UTILITY_USER_URL, false);
 		auto user_url = dpp::utility::user_url(123);
-		set_test(UTILITY_USER_URL, 
-				 user_url == dpp::utility::url_host + "/users/123" && 
+		set_test(UTILITY_USER_URL,
+				 user_url == dpp::utility::url_host + "/users/123" &&
 				 dpp::utility::user_url(0) == ""
 		);
 
 		set_test(UTILITY_MESSAGE_URL, false);
 		auto message_url = dpp::utility::message_url(1,2,3);
 		set_test(UTILITY_MESSAGE_URL,
-				 message_url == dpp::utility::url_host+ "/channels/1/2/3" && 
+				 message_url == dpp::utility::url_host+ "/channels/1/2/3" &&
 				 dpp::utility::message_url(0,2,3) == "" &&
-				 dpp::utility::message_url(1,0,3) == "" && 
+				 dpp::utility::message_url(1,0,3) == "" &&
 				 dpp::utility::message_url(1,2,0) == "" &&
 				 dpp::utility::message_url(0,0,3) == "" &&
 				 dpp::utility::message_url(0,2,0) == "" &&
 				 dpp::utility::message_url(1,0,0) == "" &&
-				 dpp::utility::message_url(0,0,0) == "" 
+				 dpp::utility::message_url(0,0,0) == ""
 		);
 
 		set_test(UTILITY_CHANNEL_URL, false);
 		auto channel_url = dpp::utility::channel_url(1,2);
-		set_test(UTILITY_CHANNEL_URL, 
+		set_test(UTILITY_CHANNEL_URL,
 				 channel_url == dpp::utility::url_host+ "/channels/1/2" &&
 				 dpp::utility::channel_url(0,2) == "" &&
 				 dpp::utility::channel_url(1,0) == "" &&
-				 dpp::utility::channel_url(0,0) == "" 
+				 dpp::utility::channel_url(0,0) == ""
 		);
 
 		set_test(UTILITY_THREAD_URL, false);
@@ -919,7 +932,7 @@ Markdown lol \\|\\|spoiler\\|\\| \\~\\~strikethrough\\~\\~ \\`small \\*code\\* b
 				 thread_url == dpp::utility::url_host+ "/channels/1/2" &&
 				 dpp::utility::thread_url(0,2) == "" &&
 				 dpp::utility::thread_url(1,0) == "" &&
-				 dpp::utility::thread_url(0,0) == "" 
+				 dpp::utility::thread_url(0,0) == ""
 		);
 	}
 
@@ -1648,7 +1661,7 @@ Markdown lol \\|\\|spoiler\\|\\| \\~\\~strikethrough\\~\\~ \\`small \\*code\\* b
 									set_test(TIMESTAMP, false);
 								}
 							} else {
-								set_test(MESSAGESGET, false);	
+								set_test(MESSAGESGET, false);
 							}
 						}  else {
 							set_test(MESSAGESGET, false);

src/unittest/test.h

@@ -264,6 +264,8 @@ DPP_TEST(CORO_EVENT_HANDLER, "coro: online event handler", tf_online | tf_coro);
 DPP_TEST(CORO_API_CALLS, "coro: online api calls", tf_online | tf_coro);
 DPP_TEST(CORO_MUMBO_JUMBO, "coro: online mumbo jumbo in event handler", tf_online | tf_coro | tf_extended);
 
+DPP_TEST(SNOWFLAKE_STD_FORMAT, "snowflake: std::format support", tf_offline);
+
 void coro_offline_tests();
 void coro_online_tests(dpp::cluster *bot);