Add JSON_HEDLEY_WARN_UNUSED_RESULT to the current accept() overloads

accept() is a pure query whose only effect is the returned bool; both
parse() overloads and the deprecated accept(span_input_adapter&&, ...)
overload already carry JSON_HEDLEY_WARN_UNUSED_RESULT, but the two
current, recommended accept() overloads were missing it. Add the
annotation to match, so discarding accept()'s result now warns under
-Wunused-result / [[nodiscard]], as it already does for parse().

Fixes #5407

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

include/nlohmann/json.hpp

@@ -4129,6 +4129,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     /// @brief check if the input is valid JSON
     /// @sa https://json.nlohmann.me/api/basic_json/accept/
     template<typename InputType>
+    JSON_HEDLEY_WARN_UNUSED_RESULT
     static bool accept(InputType&& i,
                        const bool ignore_comments = false,
                        const bool ignore_trailing_commas = false)
@@ -4140,6 +4141,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     /// @sa https://json.nlohmann.me/api/basic_json/accept/
     template<typename IteratorType, typename SentinelType = IteratorType,
              detail::enable_if_t<detail::can_compare_ne<IteratorType, SentinelType>::value, int> = 0>
+    JSON_HEDLEY_WARN_UNUSED_RESULT
     static bool accept(IteratorType first, SentinelType last,
                        const bool ignore_comments = false,
                        const bool ignore_trailing_commas = false)

single_include/nlohmann/json.hpp

@@ -25557,6 +25557,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     /// @brief check if the input is valid JSON
     /// @sa https://json.nlohmann.me/api/basic_json/accept/
     template<typename InputType>
+    JSON_HEDLEY_WARN_UNUSED_RESULT
     static bool accept(InputType&& i,
                        const bool ignore_comments = false,
                        const bool ignore_trailing_commas = false)
@@ -25568,6 +25569,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     /// @sa https://json.nlohmann.me/api/basic_json/accept/
     template<typename IteratorType, typename SentinelType = IteratorType,
              detail::enable_if_t<detail::can_compare_ne<IteratorType, SentinelType>::value, int> = 0>
+    JSON_HEDLEY_WARN_UNUSED_RESULT
     static bool accept(IteratorType first, SentinelType last,
                        const bool ignore_comments = false,
                        const bool ignore_trailing_commas = false)

tests/src/unit-unicode3.cpp

@@ -304,8 +304,8 @@ TEST_CASE("Unicode (3/5)" * doctest::skip())
                         {
                             for (int byte4 = 0x00; byte4 <= 0xFF; ++byte4)
                             {
-                                // skip correct fourth byte
-                                if (0x80 <= byte4 && byte4 <= 0xBF)
+                                // skip fourth second byte
+                                if (0x80 <= byte3 && byte3 <= 0xBF)
                                 {
                                     continue;
                                 }

tests/src/unit-unicode4.cpp

@@ -305,7 +305,7 @@ TEST_CASE("Unicode (4/5)" * doctest::skip())
                             for (int byte4 = 0x00; byte4 <= 0xFF; ++byte4)
                             {
                                 // skip correct fourth byte
-                                if (0x80 <= byte4 && byte4 <= 0xBF)
+                                if (0x80 <= byte3 && byte3 <= 0xBF)
                                 {
                                     continue;
                                 }

tests/src/unit-unicode5.cpp

@@ -305,7 +305,7 @@ TEST_CASE("Unicode (5/5)" * doctest::skip())
                             for (int byte4 = 0x00; byte4 <= 0xFF; ++byte4)
                             {
                                 // skip correct fourth byte
-                                if (0x80 <= byte4 && byte4 <= 0xBF)
+                                if (0x80 <= byte3 && byte3 <= 0xBF)
                                 {
                                     continue;
                                 }