replace FormatString template argument with fmt::basic_format_string

include/spdlog/common.h

@@ -123,13 +123,24 @@ using wmemory_buf_t = fmt::basic_memory_buffer<wchar_t, 250>;
 template<typename T>
 struct is_convertible_to_wstring_view : std::is_convertible<T, wstring_view_t>
 {};
+template<class T>
+struct is_convertible_to_wformat_string : std::is_convertible<T, fmt::wformat_string<>>
+{};
 #    endif // _WIN32
 #else
 template<typename>
 struct is_convertible_to_wstring_view : std::false_type
 {};
+template<class>
+struct is_convertible_to_wformat_string : std::false_type
+{};
 #endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
 
+template<class T>
+struct is_convertible_to_basic_format_string
+    : std::integral_constant<bool, std::is_convertible<const T &, fmt::format_string<>>::value || is_convertible_to_wformat_string<T>::value>
+{};
+
 #if defined(SPDLOG_NO_ATOMIC_LEVELS)
 using level_t = details::null_atomic_int;
 #else

include/spdlog/logger.h

@@ -77,14 +77,14 @@ public:
     logger &operator=(logger other) SPDLOG_NOEXCEPT;
     void swap(spdlog::logger &other) SPDLOG_NOEXCEPT;
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void log(source_loc loc, level::level_enum lvl, const FormatString &fmt, Args &&...args)
+    void log(source_loc loc, level::level_enum lvl, fmt::format_string<Args...> fmt, Args &&...args)
     {
         log_(loc, lvl, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void log(level::level_enum lvl, const FormatString &fmt, Args &&...args)
+    void log(level::level_enum lvl, fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
     }
@@ -134,50 +134,98 @@ public:
     }
 
     // T cannot be statically converted to string_view or wstring_view
-    template<class T, typename std::enable_if<!std::is_convertible<const T &, spdlog::string_view_t>::value &&
+    template<class T, typename std::enable_if<!is_convertible_to_basic_format_string<T>::value, int>::type = 0>
-                                                  !is_convertible_to_wstring_view<const T &>::value,
-                          int>::type = 0>
     void log(source_loc loc, level::level_enum lvl, const T &msg)
     {
         log(loc, lvl, "{}", msg);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void trace(const FormatString &fmt, Args &&...args)
+    void trace(fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(level::trace, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void debug(const FormatString &fmt, Args &&...args)
+    void debug(fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(level::debug, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void info(const FormatString &fmt, Args &&...args)
+    void info(fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(level::info, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void warn(const FormatString &fmt, Args &&...args)
+    void warn(fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(level::warn, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void error(const FormatString &fmt, Args &&...args)
+    void error(fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(level::err, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename FormatString, typename... Args>
+    template<typename... Args>
-    void critical(const FormatString &fmt, Args &&...args)
+    void critical(fmt::format_string<Args...> fmt, Args &&...args)
     {
         log(level::critical, fmt, std::forward<Args>(args)...);
     }
 
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+    template<typename... Args>
+    void log(level::level_enum lvl, fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void log(source_loc loc, level::level_enum lvl, fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log_(loc, lvl, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void trace(fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(level::trace, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void debug(fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(level::debug, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void info(fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(level::info, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void warn(fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(level::warn, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void error(fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(level::err, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename... Args>
+    void critical(fmt::wformat_string<Args...> fmt, Args &&...args)
+    {
+        log(level::critical, fmt, std::forward<Args>(args)...);
+    }
+#endif
+
     template<typename T>
     void trace(const T &msg)
     {
@@ -269,9 +317,8 @@ protected:
     details::backtracer tracer_;
 
     // common implementation for after templated public api has been resolved
-    template<typename FormatString, typename... Args, typename Char = fmt::char_t<FormatString>,
+    template<typename... Args>
-        typename std::enable_if<!std::is_same<Char, wchar_t>::value, Char>::type * = nullptr>
+    void log_(source_loc loc, level::level_enum lvl, string_view_t fmt, Args &&...args)
-    void log_(source_loc loc, level::level_enum lvl, const FormatString &fmt, Args &&...args)
     {
         bool log_enabled = should_log(lvl);
         bool traceback_enabled = tracer_.enabled();
@@ -282,7 +329,7 @@ protected:
         SPDLOG_TRY
         {
             memory_buf_t buf;
-            fmt::detail::vformat_to(buf, fmt::to_string_view(fmt), fmt::make_args_checked<Args...>(fmt, args...));
+            fmt::detail::vformat_to(buf, fmt, fmt::make_format_args(args...));
             details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
             log_it_(log_msg, log_enabled, traceback_enabled);
         }
@@ -290,9 +337,8 @@ protected:
     }
 
 #ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
-    template<typename FormatString, typename... Args, typename Char = fmt::char_t<FormatString>,
+    template<typename... Args>
-        typename std::enable_if<std::is_same<Char, wchar_t>::value, Char>::type * = nullptr>
+    void log_(source_loc loc, level::level_enum lvl, wstring_view_t fmt, Args &&...args)
-    void log_(source_loc loc, level::level_enum lvl, const FormatString &fmt, Args &&...args)
     {
         bool log_enabled = should_log(lvl);
         bool traceback_enabled = tracer_.enabled();
@@ -304,7 +350,7 @@ protected:
         {
             // format to wmemory_buffer and convert to utf8
             fmt::wmemory_buffer wbuf;
-            fmt::detail::vformat_to(wbuf, fmt::wstring_view(fmt), fmt::make_args_checked<Args...>(fmt, args...));
+            fmt::detail::vformat_to(wbuf, fmt, fmt::make_format_args<fmt::wformat_context>(args...));
             memory_buf_t buf;
             details::os::wstr_to_utf8buf(wstring_view_t(wbuf.data(), wbuf.size()), buf);
             details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));

include/spdlog/spdlog.h

@@ -127,50 +127,50 @@ SPDLOG_API spdlog::logger *default_logger_raw();
 
 SPDLOG_API void set_default_logger(std::shared_ptr<spdlog::logger> default_logger);
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void log(source_loc source, level::level_enum lvl, const FormatString &fmt, Args &&...args)
+inline void log(source_loc source, level::level_enum lvl, fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->log(source, lvl, fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void log(level::level_enum lvl, const FormatString &fmt, Args &&...args)
+inline void log(level::level_enum lvl, fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void trace(const FormatString &fmt, Args &&...args)
+inline void trace(fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->trace(fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void debug(const FormatString &fmt, Args &&...args)
+inline void debug(fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->debug(fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void info(const FormatString &fmt, Args &&...args)
+inline void info(fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->info(fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void warn(const FormatString &fmt, Args &&...args)
+inline void warn(fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->warn(fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void error(const FormatString &fmt, Args &&...args)
+inline void error(fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->error(fmt, std::forward<Args>(args)...);
 }
 
-template<typename FormatString, typename... Args>
+template<typename... Args>
-inline void critical(const FormatString &fmt, Args &&...args)
+inline void critical(fmt::format_string<Args...> fmt, Args &&...args)
 {
     default_logger_raw()->critical(fmt, std::forward<Args>(args)...);
 }
@@ -187,6 +187,56 @@ inline void log(level::level_enum lvl, const T &msg)
     default_logger_raw()->log(lvl, msg);
 }
 
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+template<typename... Args>
+inline void log(source_loc source, level::level_enum lvl, fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->log(source, lvl, fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void log(level::level_enum lvl, fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void trace(fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->trace(fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void debug(fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->debug(fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void info(fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->info(fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void warn(fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->warn(fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void error(fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->error(fmt, std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+inline void critical(fmt::wformat_string<Args...> fmt, Args &&...args)
+{
+    default_logger_raw()->critical(fmt, std::forward<Args>(args)...);
+}
+#endif
+
 template<typename T>
 inline void trace(const T &msg)
 {

tests/test_errors.cpp

@@ -29,7 +29,7 @@ TEST_CASE("default_error_handler", "[errors]]")
 
     auto logger = spdlog::create<spdlog::sinks::basic_file_sink_mt>("test-error", filename, true);
     logger->set_pattern("%v");
-    logger->info("Test message {} {}", 1);
+    logger->info(fmt::runtime("Test message {} {}"), 1);
     logger->info("Test message {}", 2);
     logger->flush();
 
@@ -49,7 +49,7 @@ TEST_CASE("custom_error_handler", "[errors]]")
     logger->set_error_handler([=](const std::string &) { throw custom_ex(); });
     logger->info("Good message #1");
 
-    REQUIRE_THROWS_AS(logger->info("Bad format msg {} {}", "xxx"), custom_ex);
+    REQUIRE_THROWS_AS(logger->info(fmt::runtime("Bad format msg {} {}"), "xxx"), custom_ex);
     logger->info("Good message #2");
     require_message_count(SIMPLE_LOG, 2);
 }
@@ -88,7 +88,7 @@ TEST_CASE("async_error_handler", "[errors]]")
             ofs << err_msg;
         });
         logger->info("Good message #1");
-        logger->info("Bad format msg {} {}", "xxx");
+        logger->info(fmt::runtime("Bad format msg {} {}"), "xxx");
         logger->info("Good message #2");
         spdlog::drop("logger"); // force logger to drain the queue and shutdown
     }