🚨 fix warnings

include/nlohmann/detail/conversions/from_json.hpp

@@ -25,13 +25,13 @@
 namespace nlohmann::detail
 {
 namespace std_fs = std::experimental::filesystem;
-}
+} // namespace nlohmann::detail
 #else
 #include <filesystem>
 namespace nlohmann::detail
 {
 namespace std_fs = std::filesystem;
-}
+} // namespace nlohmann::detail
 #endif
 #endif
 

include/nlohmann/detail/conversions/to_json.hpp

@@ -21,13 +21,13 @@
 namespace nlohmann::detail
 {
 namespace std_fs = std::experimental::filesystem;
-}
+} // namespace nlohmann::detail
 #else
 #include <filesystem>
 namespace nlohmann::detail
 {
 namespace std_fs = std::filesystem;
-}
+} // namespace nlohmann::detail
 #endif
 #endif
 

include/nlohmann/detail/meta/cpp_future.hpp

@@ -147,8 +147,6 @@ struct static_const
     static constexpr T value{};
 };
 
-template<typename T>
-constexpr T static_const<T>::value;
 
 }  // namespace detail
 }  // namespace nlohmann

single_include/nlohmann/json.hpp

@@ -3314,8 +3314,6 @@ struct static_const
     static constexpr T value{};
 };
 
-template<typename T>
-constexpr T static_const<T>::value;
 
 }  // namespace detail
 }  // namespace nlohmann
@@ -3973,13 +3971,13 @@ T conditional_static_cast(U value)
 namespace nlohmann::detail
 {
 namespace std_fs = std::experimental::filesystem;
-}
+} // namespace nlohmann::detail
 #else
 #include <filesystem>
 namespace nlohmann::detail
 {
 namespace std_fs = std::filesystem;
-}
+} // namespace nlohmann::detail
 #endif
 #endif
 
@@ -4661,13 +4659,13 @@ class tuple_element<N, ::nlohmann::detail::iteration_proxy_value<IteratorType >>
 namespace nlohmann::detail
 {
 namespace std_fs = std::experimental::filesystem;
-}
+} // namespace nlohmann::detail
 #else
 #include <filesystem>
 namespace nlohmann::detail
 {
 namespace std_fs = std::filesystem;
-}
+} // namespace nlohmann::detail
 #endif
 #endif
 

test/src/unit-regression1.cpp

@@ -205,7 +205,7 @@ TEST_CASE("regression tests 1")
         // check if the actual value was stored
         CHECK(j2 == 102);
 
-        static_assert(std::is_same<decltype(anon_enum_value), decltype(u)>::value, "");
+        static_assert(std::is_same<decltype(anon_enum_value), decltype(u)>::value, "types must be the same");
 
         j.push_back(json::object(
         {

test/src/unit-regression2.cpp

@@ -48,18 +48,34 @@ using ordered_json = nlohmann::ordered_json;
 
 #ifdef JSON_HAS_CPP_17
 #include <variant>
+
+// set JSON_STD_FILESYSTEM_EXPERIMENTAL to 1 if <experimental/filesystem> should be taken instead of <filesystem>
+#if defined(__cpp_lib_filesystem)
+    #define JSON_STD_FILESYSTEM_EXPERIMENTAL 0
+#elif defined(__cpp_lib_experimental_filesystem)
+    #define JSON_STD_FILESYSTEM_EXPERIMENTAL 1
+#elif !defined(__has_include)
+    #define JSON_STD_FILESYSTEM_EXPERIMENTAL 1
+#elif __has_include(<filesystem>)
+    #define JSON_STD_FILESYSTEM_EXPERIMENTAL 0
+#elif __has_include(<experimental/filesystem>)
+    #define JSON_STD_FILESYSTEM_EXPERIMENTAL 1
+#else
+    #define JSON_STD_FILESYSTEM_EXPERIMENTAL 0
+#endif
+
 #if JSON_STD_FILESYSTEM_EXPERIMENTAL
 #include <experimental/filesystem>
 namespace nlohmann::detail
 {
 namespace std_fs = std::experimental::filesystem;
-}
+} // namespace nlohmann::detail
 #else
 #include <filesystem>
 namespace nlohmann::detail
 {
 namespace std_fs = std::filesystem;
-}
+} // namespace nlohmann::detail
 #endif
 #endif
 
@@ -504,15 +520,15 @@ TEST_CASE("regression tests 2")
 
     SECTION("issue #1805 - A pair<T1, T2> is json constructible only if T1 and T2 are json constructible")
     {
-        static_assert(!std::is_constructible<json, std::pair<std::string, NotSerializableData>>::value, "");
+        static_assert(!std::is_constructible<json, std::pair<std::string, NotSerializableData>>::value, "unexpected result");
-        static_assert(!std::is_constructible<json, std::pair<NotSerializableData, std::string>>::value, "");
+        static_assert(!std::is_constructible<json, std::pair<NotSerializableData, std::string>>::value, "unexpected result");
-        static_assert(std::is_constructible<json, std::pair<int, std::string>>::value, "");
+        static_assert(std::is_constructible<json, std::pair<int, std::string>>::value, "unexpected result");
     }
     SECTION("issue #1825 - A tuple<Args..> is json constructible only if all T in Args are json constructible")
     {
-        static_assert(!std::is_constructible<json, std::tuple<std::string, NotSerializableData>>::value, "");
+        static_assert(!std::is_constructible<json, std::tuple<std::string, NotSerializableData>>::value, "unexpected result");
-        static_assert(!std::is_constructible<json, std::tuple<NotSerializableData, std::string>>::value, "");
+        static_assert(!std::is_constructible<json, std::tuple<NotSerializableData, std::string>>::value, "unexpected result");
-        static_assert(std::is_constructible<json, std::tuple<int, std::string>>::value, "");
+        static_assert(std::is_constructible<json, std::tuple<int, std::string>>::value, "unexpected result");
     }
 
     SECTION("issue #1983 - JSON patch diff for op=add formation is not as per standard (RFC 6902)")
@@ -709,7 +725,7 @@ TEST_CASE("regression tests 2")
 
     SECTION("issue #2825 - Properly constrain the basic_json conversion operator")
     {
-        static_assert(std::is_copy_assignable<nlohmann::ordered_json>::value, "");
+        static_assert(std::is_copy_assignable<nlohmann::ordered_json>::value, "ordered_json must be copy assignable");
     }
 
     SECTION("issue #2958 - Inserting in unordered json using a pointer retains the leading slash")