Merge branch 'develop' of https://github.com/nlohmann/json into feature/optional

 Conflicts:

	test/src/unit-conversions.cpp

include/nlohmann/detail/hash.hpp

@@ -83,19 +83,19 @@ std::size_t hash(const BasicJsonType& j)
             return combine(type, h);
         }
 
-        case nlohmann::detail::value_t::number_unsigned:
+        case BasicJsonType::value_t::number_unsigned:
         {
             const auto h = std::hash<number_unsigned_t> {}(j.template get<number_unsigned_t>());
             return combine(type, h);
         }
 
-        case nlohmann::detail::value_t::number_float:
+        case BasicJsonType::value_t::number_float:
         {
             const auto h = std::hash<number_float_t> {}(j.template get<number_float_t>());
             return combine(type, h);
         }
 
-        case nlohmann::detail::value_t::binary:
+        case BasicJsonType::value_t::binary:
         {
             auto seed = combine(type, j.get_binary().size());
             const auto h = std::hash<bool> {}(j.get_binary().has_subtype());
@@ -108,8 +108,9 @@ std::size_t hash(const BasicJsonType& j)
             return seed;
         }
 
-        default: // LCOV_EXCL_LINE
-            JSON_ASSERT(false); // LCOV_EXCL_LINE
+        default:                   // LCOV_EXCL_LINE
+            JSON_ASSERT(false);    // LCOV_EXCL_LINE
+            return 0;              // LCOV_EXCL_LINE
     }
 }
 

include/nlohmann/detail/input/binary_reader.hpp

@@ -752,8 +752,9 @@ class binary_reader
                         return parse_cbor_internal(true, tag_handler);
                     }
 
-                    default:            // LCOV_EXCL_LINE
+                    default:                 // LCOV_EXCL_LINE
                         JSON_ASSERT(false);  // LCOV_EXCL_LINE
+                        return false;        // LCOV_EXCL_LINE
                 }
             }
 

include/nlohmann/detail/iterators/iter_impl.hpp

@@ -163,7 +163,7 @@ class iter_impl
         return *this;
     }
 
-  private:
+  JSON_PRIVATE_UNLESS_TESTED:
     /*!
     @brief set the iterator to the first value
     @pre The iterator is initialized; i.e. `m_object != nullptr`.
@@ -627,7 +627,7 @@ class iter_impl
         return operator*();
     }
 
-  private:
+  JSON_PRIVATE_UNLESS_TESTED:
     /// associated JSON instance
     pointer m_object = nullptr;
     /// the actual iterator of the associated instance

include/nlohmann/detail/iterators/primitive_iterator.hpp

@@ -23,6 +23,7 @@ class primitive_iterator_t
     static constexpr difference_type begin_value = 0;
     static constexpr difference_type end_value = begin_value + 1;
 
+  JSON_PRIVATE_UNLESS_TESTED:
     /// iterator as signed integer type
     difference_type m_it = (std::numeric_limits<std::ptrdiff_t>::min)();
 

include/nlohmann/detail/json_pointer.hpp

@@ -375,6 +375,7 @@ class json_pointer
         return static_cast<size_type>(res);
     }
 
+  JSON_PRIVATE_UNLESS_TESTED:
     json_pointer top() const
     {
         if (JSON_HEDLEY_UNLIKELY(empty()))
@@ -387,6 +388,7 @@ class json_pointer
         return result;
     }
 
+  private:
     /*!
     @brief create and return a reference to the pointed to value
 
@@ -823,6 +825,7 @@ class json_pointer
         {}
     }
 
+  JSON_PRIVATE_UNLESS_TESTED:
     /// escape "~" to "~0" and "/" to "~1"
     static std::string escape(std::string s)
     {
@@ -838,6 +841,7 @@ class json_pointer
         replace_substring(s, "~0", "~");
     }
 
+  private:
     /*!
     @param[in] reference_string  the reference string to the current value
     @param[in] value             the value to consider

include/nlohmann/detail/json_ref.hpp

@@ -17,19 +17,14 @@ class json_ref
 
     json_ref(value_type&& value)
         : owned_value(std::move(value))
-        , value_ref(&owned_value)
-        , is_rvalue(true)
     {}
 
     json_ref(const value_type& value)
-        : value_ref(const_cast<value_type*>(&value))
-        , is_rvalue(false)
+        : value_ref(&value)
     {}
 
     json_ref(std::initializer_list<json_ref> init)
         : owned_value(init)
-        , value_ref(&owned_value)
-        , is_rvalue(true)
     {}
 
     template <
@@ -37,8 +32,6 @@ class json_ref
         enable_if_t<std::is_constructible<value_type, Args...>::value, int> = 0 >
     json_ref(Args && ... args)
         : owned_value(std::forward<Args>(args)...)
-        , value_ref(&owned_value)
-        , is_rvalue(true)
     {}
 
     // class should be movable only
@@ -50,27 +43,26 @@ class json_ref
 
     value_type moved_or_copied() const
     {
-        if (is_rvalue)
+        if (value_ref == nullptr)
         {
-            return std::move(*value_ref);
+            return std::move(owned_value);
         }
         return *value_ref;
     }
 
     value_type const& operator*() const
     {
-        return *static_cast<value_type const*>(value_ref);
+        return value_ref ? *value_ref : owned_value;
     }
 
     value_type const* operator->() const
     {
-        return static_cast<value_type const*>(value_ref);
+        return &** this;
     }
 
   private:
     mutable value_type owned_value = nullptr;
-    value_type* value_ref = nullptr;
-    const bool is_rvalue = true;
+    value_type const* value_ref = nullptr;
 };
 }  // namespace detail
 }  // namespace nlohmann

include/nlohmann/detail/macro_scope.hpp

@@ -91,6 +91,13 @@
     #define JSON_ASSERT(x) assert(x)
 #endif
 
+// allow to access some private functions (needed by the test suite)
+#if defined(JSON_TESTS_PRIVATE)
+    #define JSON_PRIVATE_UNLESS_TESTED public
+#else
+    #define JSON_PRIVATE_UNLESS_TESTED private
+#endif
+
 /*!
 @brief macro to briefly define a mapping between an enum and JSON
 @def NLOHMANN_JSON_SERIALIZE_ENUM

include/nlohmann/detail/macro_unscope.hpp

@@ -14,6 +14,7 @@
 #undef JSON_CATCH
 #undef JSON_THROW
 #undef JSON_TRY
+#undef JSON_PRIVATE_UNLESS_TESTED
 #undef JSON_HAS_CPP_14
 #undef JSON_HAS_CPP_17
 #undef NLOHMANN_BASIC_JSON_TPL_DECLARATION

include/nlohmann/detail/meta/cpp_future.hpp

@@ -2,19 +2,32 @@
 
 #include <cstddef> // size_t
 #include <type_traits> // conditional, enable_if, false_type, integral_constant, is_constructible, is_integral, is_same, remove_cv, remove_reference, true_type
+#include <utility> // index_sequence, make_index_sequence, index_sequence_for
+
+#include <nlohmann/detail/macro_scope.hpp>
 
 namespace nlohmann
 {
 namespace detail
 {
-// alias templates to reduce boilerplate
-template<bool B, typename T = void>
-using enable_if_t = typename std::enable_if<B, T>::type;
 
 template<typename T>
 using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
 
-// implementation of C++14 index_sequence and affiliates
+#ifdef JSON_HAS_CPP_14
+
+// the following utilities are natively available in C++14
+using std::enable_if_t;
+using std::index_sequence;
+using std::make_index_sequence;
+using std::index_sequence_for;
+
+#else
+
+// alias templates to reduce boilerplate
+template<bool B, typename T = void>
+using enable_if_t = typename std::enable_if<B, T>::type;
+
 // source: https://stackoverflow.com/a/32223343
 template<std::size_t... Ints>
 struct index_sequence
@@ -45,6 +58,8 @@ template<> struct make_index_sequence<1> : index_sequence<0> {};
 template<typename... Ts>
 using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
 
+#endif
+
 // dispatch utility (taken from ranges-v3)
 template<unsigned N> struct priority_tag : priority_tag < N - 1 > {};
 template<> struct priority_tag<0> {};
@@ -58,5 +73,6 @@ struct static_const
 
 template<typename T>
 constexpr T static_const<T>::value;
+
 }  // namespace detail
 }  // namespace nlohmann

include/nlohmann/detail/meta/type_traits.hpp

@@ -168,7 +168,9 @@ struct is_iterator_traits<iterator_traits<T>>
         is_detected<reference_t, traits>::value;
 };
 
-// source: https://stackoverflow.com/a/37193089/4116453
+// The following implementation of is_complete_type is taken from
+// https://blogs.msdn.microsoft.com/vcblog/2015/12/02/partial-support-for-expression-sfinae-in-vs-2015-update-1/
+// and is written by Xiang Fan who agreed to using it in this library.
 
 template<typename T, typename = void>
 struct is_complete_type : std::false_type {};
@@ -186,7 +188,6 @@ struct is_compatible_object_type_impl <
     enable_if_t < is_detected<mapped_type_t, CompatibleObjectType>::value&&
     is_detected<key_type_t, CompatibleObjectType>::value >>
 {
-
     using object_t = typename BasicJsonType::object_t;
 
     // macOS's is_constructible does not play well with nonesuch...

include/nlohmann/detail/output/serializer.hpp

@@ -362,7 +362,7 @@ class serializer
         }
     }
 
-  private:
+  JSON_PRIVATE_UNLESS_TESTED:
     /*!
     @brief dump escaped string
 
@@ -625,6 +625,7 @@ class serializer
         }
     }
 
+  private:
     /*!
     @brief count digits
 
@@ -880,6 +881,7 @@ class serializer
             }
         };
 
+        JSON_ASSERT(byte < utf8d.size());
         const std::uint8_t type = utf8d[byte];
 
         codep = (state != UTF8_ACCEPT)