Regenerate single_include after merging develop

The merge commit kept develop's single_include/nlohmann/json.hpp because
make amalgamate saw it as up to date.

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

.github/workflows/ubuntu.yml

@@ -100,7 +100,7 @@ jobs:
     container: ubuntu:focal
     strategy:
       matrix:
-        target: [ci_cmake_flags, ci_test_diagnostics, ci_test_diagnostic_positions, ci_test_noexceptions, ci_test_noimplicitconversions, ci_test_legacycomparison, ci_test_noglobaludls, ci_test_disableenumserialization, ci_test_disabletuplereferenceconversion, ci_test_skiplibraryversioncheck, ci_test_simdutf, ci_test_strict_nul_handling, ci_test_no_thread_local]
+        target: [ci_cmake_flags, ci_test_diagnostics, ci_test_diagnostic_positions, ci_test_noexceptions, ci_test_noimplicitconversions, ci_test_legacycomparison, ci_test_noglobaludls, ci_test_disableenumserialization, ci_test_skiplibraryversioncheck, ci_test_simdutf, ci_test_strict_nul_handling, ci_test_no_thread_local]
     steps:
       - name: Install build-essential
         run: apt-get update ; apt-get install -y build-essential unzip wget git libssl-dev

BUILD.bazel

@@ -53,7 +53,6 @@ cc_library(
         "include/nlohmann/detail/meta/detected.hpp",
         "include/nlohmann/detail/meta/identity_tag.hpp",
         "include/nlohmann/detail/meta/is_sax.hpp",
-        "include/nlohmann/detail/meta/logic.hpp",
         "include/nlohmann/detail/meta/std_fs.hpp",
         "include/nlohmann/detail/meta/type_traits.hpp",
         "include/nlohmann/detail/meta/void_t.hpp",

CMakeLists.txt

@@ -55,7 +55,6 @@ option(JSON_Diagnostic_Positions           "Enable diagnostic positions." OFF)
 option(JSON_GlobalUDLs                     "Place user-defined string literals in the global namespace." ON)
 option(JSON_ImplicitConversions            "Enable implicit conversions." ON)
 option(JSON_DisableEnumSerialization       "Disable default integer enum serialization." OFF)
-option(JSON_DisableTupleReferenceConversion "Disable conversion from a one-element tuple of a JSON reference." OFF)
 option(JSON_LegacyDiscardedValueComparison "Enable legacy discarded value comparison." OFF)
 option(JSON_Install                        "Install CMake targets during install step." ${MAIN_PROJECT})
 option(JSON_MultipleHeaders                "Use non-amalgamated version of the library." ON)
@@ -102,10 +101,6 @@ if (JSON_DisableEnumSerialization)
     message(STATUS "Enum integer serialization is disabled (JSON_DISABLE_ENUM_SERIALIZATION=1)")
 endif()
 
-if (JSON_DisableTupleReferenceConversion)
-    message(STATUS "Tuple reference conversion is disabled (JSON_DISABLE_TUPLE_REFERENCE_CONVERSION=1)")
-endif()
-
 if (JSON_LegacyDiscardedValueComparison)
     message(STATUS "Legacy discarded value comparison enabled (JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON=1)")
 endif()
@@ -148,7 +143,6 @@ target_compile_definitions(
     $<$<NOT:$<BOOL:${JSON_GlobalUDLs}>>:JSON_USE_GLOBAL_UDLS=0>
     $<$<NOT:$<BOOL:${JSON_ImplicitConversions}>>:JSON_USE_IMPLICIT_CONVERSIONS=0>
     $<$<BOOL:${JSON_DisableEnumSerialization}>:JSON_DISABLE_ENUM_SERIALIZATION=1>
-    $<$<BOOL:${JSON_DisableTupleReferenceConversion}>:JSON_DISABLE_TUPLE_REFERENCE_CONVERSION=1>
     $<$<BOOL:${JSON_Diagnostics}>:JSON_DIAGNOSTICS=1>
     $<$<BOOL:${JSON_Diagnostic_Positions}>:JSON_DIAGNOSTIC_POSITIONS=1>
     $<$<BOOL:${JSON_LegacyDiscardedValueComparison}>:JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON=1>

cmake/ci.cmake

@@ -276,20 +276,6 @@ add_custom_target(ci_test_disableenumserialization
     COMMENT "Compile and test with enum serialization disabled"
 )
 
-###############################################################################
-# Disable conversion from a one-element tuple of a JSON reference.
-###############################################################################
-
-add_custom_target(ci_test_disabletuplereferenceconversion
-    COMMAND ${CMAKE_COMMAND}
-    -DCMAKE_BUILD_TYPE=Debug -GNinja
-    -DJSON_BuildTests=ON -DJSON_FastTests=ON -DJSON_DisableTupleReferenceConversion=ON
-    -S${PROJECT_SOURCE_DIR} -B${PROJECT_BINARY_DIR}/build_disabletuplereferenceconversion
-    COMMAND ${CMAKE_COMMAND} --build ${PROJECT_BINARY_DIR}/build_disabletuplereferenceconversion
-    COMMAND cd ${PROJECT_BINARY_DIR}/build_disabletuplereferenceconversion && ${CMAKE_CTEST_COMMAND} --parallel ${N} --output-on-failure
-    COMMENT "Compile and test with tuple reference conversion disabled"
-)
-
 ###############################################################################
 # Skip the multiple-inclusion library version check.
 ###############################################################################

docs/docset/docSet.sql

@@ -210,7 +210,6 @@ INSERT INTO searchIndex(name, type, path) VALUES ('JSON_CATCH_USER', 'Macro', 'a
 INSERT INTO searchIndex(name, type, path) VALUES ('JSON_DIAGNOSTICS', 'Macro', 'api/macros/json_diagnostics/index.html');
 INSERT INTO searchIndex(name, type, path) VALUES ('JSON_DIAGNOSTIC_POSITIONS', 'Macro', 'api/macros/json_diagnostic_positions/index.html');
 INSERT INTO searchIndex(name, type, path) VALUES ('JSON_DISABLE_ENUM_SERIALIZATION', 'Macro', 'api/macros/json_disable_enum_serialization/index.html');
-INSERT INTO searchIndex(name, type, path) VALUES ('JSON_DISABLE_TUPLE_REFERENCE_CONVERSION', 'Macro', 'api/macros/json_disable_tuple_reference_conversion/index.html');
 INSERT INTO searchIndex(name, type, path) VALUES ('JSON_HAS_CPP_11', 'Macro', 'api/macros/json_has_cpp_11/index.html');
 INSERT INTO searchIndex(name, type, path) VALUES ('JSON_HAS_CPP_14', 'Macro', 'api/macros/json_has_cpp_11/index.html');
 INSERT INTO searchIndex(name, type, path) VALUES ('JSON_HAS_CPP_17', 'Macro', 'api/macros/json_has_cpp_11/index.html');

docs/mkdocs/docs/api/basic_json/basic_json.md

@@ -159,8 +159,6 @@ basic_json(basic_json&& other) noexcept;
     - `CompatibleType` is not `basic_json` (to avoid hijacking copy/move constructors),
     - `CompatibleType` is not a different `basic_json` type (i.e. with different template arguments)
     - `CompatibleType` is not a `basic_json` nested type (e.g., `json_pointer`, `iterator`, etc.)
-    - if [`JSON_DISABLE_TUPLE_REFERENCE_CONVERSION`](../macros/json_disable_tuple_reference_conversion.md) is defined
-      to `1`: `CompatibleType` is not a one-element `std::tuple` holding a reference to `basic_json`
     - `json_serializer<U>` (with `U = uncvref_t<CompatibleType>`) has a `to_json(basic_json_t&, CompatibleType&&)`
        method
 

docs/mkdocs/docs/api/basic_json/to_bjdata.md

@@ -56,8 +56,6 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
 
 - Throws [`other_error.502`](../../home/exceptions.md#jsonexceptionother_error502) if `use_type` is true and `use_size`
   is false.
-- Throws [type_error.316](../../home/exceptions.md#jsonexceptiontype_error316) if a string or object key in `j` is
-  not valid UTF-8
 
 ## Complexity
 
@@ -91,5 +89,4 @@ Linear in the size of the JSON value `j`.
 ## Version history
 
 - Added in version 3.11.0.
-- BJData version parameter (for draft3 binary encoding) added in version 3.12.0.
-- Throwing `type_error.316` for a string or object key that is not valid UTF-8 added in version 3.13.0.
+- BJData version parameter (for draft3 binary encoding) added in version 3.12.0.

docs/mkdocs/docs/api/basic_json/to_bson.md

@@ -46,8 +46,6 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
 - Throws [`out_of_range.415`](../../home/exceptions.md#jsonexceptionout_of_range415) if the subtype of a binary value
   exceeds 255, the maximum of the BSON binary subtype; example:
   `"subtype 70000 is too large for the BSON binary subtype (max 255)"`
-- Throws [type_error.316](../../home/exceptions.md#jsonexceptiontype_error316) if a string or object key is
-  not valid UTF-8
 
 ## Complexity
 
@@ -84,5 +82,3 @@ pass before anything is written.
 - Added in version 3.4.0.
 - Linear in the size of `j`, and no longer limited by the call stack for deeply nested values, since version 3.13.0.
 - `out_of_range.415` is now detected before anything is written, like the other exceptions above, since version 3.13.0.
-- Throwing `type_error.316` for a string value or object key that is not valid UTF-8, detected before anything is
-  written, added in version 3.13.0.

docs/mkdocs/docs/api/basic_json/to_cbor.md

@@ -35,11 +35,6 @@ The exact mapping and its limitations are described on a [dedicated page](../../
 
 Strong guarantee: if an exception is thrown, there are no changes in the JSON value.
 
-## Exceptions
-
-- Throws [type_error.316](../../home/exceptions.md#jsonexceptiontype_error316) if a string or object key in `j` is
-  not valid UTF-8
-
 ## Complexity
 
 Linear in the size of the JSON value `j`.
@@ -73,4 +68,3 @@ Linear in the size of the JSON value `j`.
 
 - Added in version 2.0.9.
 - Compact representation of floating-point numbers added in version 3.8.0.
-- Throwing `type_error.316` for a string or object key that is not valid UTF-8 added in version 3.13.0.

docs/mkdocs/docs/api/basic_json/to_ubjson.md

@@ -49,8 +49,6 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
 
 - Throws [`other_error.502`](../../home/exceptions.md#jsonexceptionother_error502) if `use_type` is true and `use_size`
   is false.
-- Throws [type_error.316](../../home/exceptions.md#jsonexceptiontype_error316) if a string or object key in `j` is
-  not valid UTF-8
 
 ## Complexity
 
@@ -84,4 +82,3 @@ Linear in the size of the JSON value `j`.
 ## Version history
 
 - Added in version 3.1.0.
-- Throwing `type_error.316` for a string or object key that is not valid UTF-8 added in version 3.13.0.

docs/mkdocs/docs/api/macros/index.md

@@ -53,7 +53,6 @@ header. See also the [macro overview page](../../features/macros.md).
 
 - [**JSON_BRACE_INIT_COPY_SEMANTICS**](json_brace_init_copy_semantics.md) - opt in to copy/move semantics for single-element brace initialization
 - [**JSON_DISABLE_ENUM_SERIALIZATION**](json_disable_enum_serialization.md) - switch off default serialization/deserialization functions for enums
-- [**JSON_DISABLE_TUPLE_REFERENCE_CONVERSION**](json_disable_tuple_reference_conversion.md) - switch off conversion from a one-element tuple of a JSON reference
 - [**JSON_USE_IMPLICIT_CONVERSIONS**](json_use_implicit_conversions.md) - control implicit conversions
 
 ## Comparison behavior

docs/mkdocs/docs/api/macros/json_disable_tuple_reference_conversion.md

@@ -1,114 +0,0 @@
-# JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-
-```cpp
-#define JSON_DISABLE_TUPLE_REFERENCE_CONVERSION /* value */
-```
-
-When defined to `1`, a `basic_json` value can no longer be constructed from a one-element `std::tuple` whose element is
-a reference to that `basic_json` type, such as `std::tuple<json&>`, `std::tuple<const json&>`, or `std::tuple<json&&>`.
-These are the tuples created by `std::forward_as_tuple(j)`.
-
-## Default definition
-
-The default value is `0` (disabled — existing behavior is preserved).
-
-```cpp
-#define JSON_DISABLE_TUPLE_REFERENCE_CONVERSION 0
-```
-
-## Notes
-
-!!! note "Background"
-
-    By default, `basic_json` can be constructed from any `std::tuple` whose elements can be converted to JSON; the result
-    is an array. This includes `std::tuple<json&>`, which becomes a one-element array.
-
-    `std::tuple` only converts another tuple element by element if its element type cannot be constructed from the whole
-    source tuple. Because `json` *can* be constructed from `std::tuple<json&>`, `std::tuple` instead converts the whole
-    tuple into a single `json` value. This has two surprising effects:
-
-    ```cpp
-    json j = true;
-
-    // rejected by some standard libraries (e.g., libc++); with others, the
-    // reference binds to a temporary that is destroyed right away
-    std::tuple<const json&> t1(std::forward_as_tuple(j));
-
-    // compiles, but std::get<0>(t2) is [true], not true
-    std::tuple<json> t2(std::forward_as_tuple(j));
-    ```
-
-    Enabling this macro removes the conversion, so both tuples are converted element by element: `std::get<0>(t1)`
-    refers to `j`, and `std::get<0>(t2)` is a copy of `j` (see [#2226](https://github.com/nlohmann/json/issues/2226)).
-
-!!! warning "Opt-in only"
-
-    This macro must be defined **before** including `<nlohmann/json.hpp>`. Defining it after the include has no effect.
-
-!!! note "Affected conversions"
-
-    Only one-element tuples holding a reference to the **same** `basic_json` type are affected. Constructing a JSON value
-    from them no longer compiles:
-
-    ```cpp
-    json j = true;
-    json a = std::forward_as_tuple(j);  // error with the macro enabled
-    json b = json::array({j});          // use this instead: [true]
-    ```
-
-    Tuples holding a JSON value (`std::make_tuple(j)`), tuples with more than one element, and tuples holding references
-    to other types (including other `basic_json` specializations) are converted to arrays as before.
-
-!!! hint "CMake option"
-
-    This behavior can also be controlled with the CMake option
-    [`JSON_DisableTupleReferenceConversion`](../../integration/cmake.md#json_disabletuplereferenceconversion)
-    (`OFF` by default) which defines `JSON_DISABLE_TUPLE_REFERENCE_CONVERSION` accordingly.
-
-## Examples
-
-??? example "Default behavior (macro not defined)"
-
-    ```cpp
-    #include <nlohmann/json.hpp>
-
-    using json = nlohmann::json;
-
-    int main()
-    {
-        json j = true;
-
-        std::tuple<json> t(std::forward_as_tuple(j));
-        // std::get<0>(t) is [true] -- the whole tuple was converted
-    }
-    ```
-
-??? example "Conversion disabled (macro defined to 1)"
-
-    ```cpp
-    #define JSON_DISABLE_TUPLE_REFERENCE_CONVERSION 1
-    #include <nlohmann/json.hpp>
-
-    using json = nlohmann::json;
-
-    int main()
-    {
-        json j = true;
-
-        std::tuple<json> t(std::forward_as_tuple(j));
-        // std::get<0>(t) is true -- a copy of j
-
-        std::tuple<const json&> r(std::forward_as_tuple(j));
-        // std::get<0>(r) refers to j
-    }
-    ```
-
-## See also
-
-- [**basic_json(CompatibleType&&)**](../basic_json/basic_json.md) - the affected constructor
-- [:simple-cmake: JSON_DisableTupleReferenceConversion](../../integration/cmake.md#json_disabletuplereferenceconversion) -
-  CMake option to control the macro
-
-## Version history
-
-- Added in version 3.13.0.

docs/mkdocs/docs/features/binary_formats/bjdata.md

@@ -63,12 +63,6 @@ The library uses the following mapping from JSON values types to BJData types ac
 
       - strings with more than 18446744073709551615 bytes, i.e., $2^{64}-1$ bytes (theoretical)
 
-!!! warning "UTF-8 validation of string values and object keys"
-
-    BJData strings must use UTF-8 encoding. `to_bjdata()` validates the bytes of every string value and object key
-    and throws [`type_error.316`](../../home/exceptions.md#jsonexceptiontype_error316) for ill-formed UTF-8, so a
-    value with such a string cannot be serialized in the first place.
-
 !!! info "Unused BJData markers"
 
     The following markers are not used in the conversion:
@@ -214,13 +208,6 @@ The library maps BJData types to JSON value types as follows:
 
     The mapping is **complete** in the sense that any BJData value can be converted to a JSON value.
 
-!!! warning "UTF-8 validation of string values and object keys"
-
-    This library validates the bytes of every string value and object key at decode time and rejects ill-formed
-    UTF-8 with a [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with
-    `allow_exceptions` set to `false`, a discarded value), rather than only failing later when the resulting value
-    is dumped.
-
 !!! info "Round trips"
 
     A value returned by [`from_bjdata`](../../api/basic_json/from_bjdata.md) can be serialized with

docs/mkdocs/docs/features/binary_formats/bson.md

@@ -115,12 +115,8 @@ The library maps BSON record types to JSON value types as follows:
     bytes of every such string at decode time and rejects ill-formed UTF-8 with a
     [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with `allow_exceptions`
     set to `false`, a discarded value), rather than only failing later when the resulting value is dumped. Element
-    (key) names and `binary` values (type `0x05`) are unaffected and are never validated on read, since they are read
-    byte-by-byte as a C string, or are not required to hold text, respectively. `to_bson()` validates both string
-    values and element names and throws
-    [`type_error.316`](../../home/exceptions.md#jsonexceptiontype_error316) for ill-formed UTF-8 in either, so an
-    object with such a key or value cannot be produced in the first place, even though `from_bson()` would accept it
-    from another source.
+    (key) names and `binary` values (type `0x05`) are unaffected and are never validated, since they are read
+    byte-by-byte as a C string, or are not required to hold text, respectively.
 
 ??? example
 

docs/mkdocs/docs/features/binary_formats/cbor.md

@@ -197,9 +197,7 @@ The library maps CBOR types to JSON value types as follows:
     [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with
     `allow_exceptions` set to `false`, a discarded value), rather than only failing later when the resulting value is
     dumped. Byte strings (major type 2) are unaffected and are never validated, since they are not required to hold
-    text. `to_cbor()` validates string values and object keys the same way and throws
-    [`type_error.316`](../../home/exceptions.md#jsonexceptiontype_error316) for ill-formed UTF-8, so a value with
-    such a string cannot be serialized in the first place.
+    text.
 
 !!! warning "Tagged items"
 

docs/mkdocs/docs/features/binary_formats/messagepack.md

@@ -153,15 +153,14 @@ The library maps MessagePack types to JSON value types as follows:
     This applies to the [SAX interface](../parsing/sax_interface.md) as well, as the key is read before it is passed
     on. Such input needs a general-purpose MessagePack library instead.
 
-!!! warning "Ill-formed UTF-8 in string values"
+!!! warning "UTF-8 validation of string values"
 
-    The MessagePack specification explicitly allows a `str` value (`fixstr`, `str 8`, `str 16`, `str 32`) to contain
-    a byte sequence that is not valid UTF-8, and expects a deserializer to hand the original bytes back unchanged.
-    This library follows that: `from_msgpack()` reads `str` bytes (object keys included) as-is, without validating
-    them, and `to_msgpack()` writes them back as-is, so such a value round-trips through `from_msgpack(to_msgpack(j))`
-    byte for byte. However, [`dump()`](../../api/basic_json/dump.md) still requires valid UTF-8 and throws
-    [`type_error.316`](../../home/exceptions.md#jsonexceptiontype_error316) for a value read this way, unless an
-    error handler is passed that replaces or ignores the ill-formed bytes.
+    The MessagePack specification requires `str` values (`fixstr`, `str 8`, `str 16`, `str 32`) to be valid UTF-8.
+    This library validates the bytes of every such string (object keys included) at decode time and rejects
+    ill-formed UTF-8 with a [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or,
+    with `allow_exceptions` set to `false`, a discarded value), rather than only failing later when the resulting
+    value is dumped. `bin`/`ext`/`fixext` values are unaffected and are never validated, since they are not required
+    to hold text.
 
 ??? example
 

docs/mkdocs/docs/features/binary_formats/ubjson.md

@@ -47,12 +47,6 @@ The library uses the following mapping from JSON values types to UBJSON types ac
 
       - strings with more than 9223372036854775807 bytes (theoretical)
 
-!!! warning "UTF-8 validation of string values and object keys"
-
-    UBJSON's required string encoding is UTF-8. `to_ubjson()` validates the bytes of every string value and object
-    key and throws [`type_error.316`](../../home/exceptions.md#jsonexceptiontype_error316) for ill-formed UTF-8, so
-    a value with such a string cannot be serialized in the first place.
-
 !!! info "Unused UBJSON markers"
 
     The following markers are not used in the conversion:
@@ -126,13 +120,6 @@ The library maps UBJSON types to JSON value types as follows:
 
     The mapping is **complete** in the sense that any UBJSON value can be converted to a JSON value.
 
-!!! warning "UTF-8 validation of string values and object keys"
-
-    This library validates the bytes of every string value and object key at decode time and rejects ill-formed
-    UTF-8 with a [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with
-    `allow_exceptions` set to `false`, a discarded value), rather than only failing later when the resulting value
-    is dumped.
-
 ??? example
 
     ```cpp

docs/mkdocs/docs/features/macros.md

@@ -83,13 +83,6 @@ When defined, default parse and serialize functions for enums are excluded and h
 
 See [full documentation of `JSON_DISABLE_ENUM_SERIALIZATION`](../api/macros/json_disable_enum_serialization.md).
 
-## `JSON_DISABLE_TUPLE_REFERENCE_CONVERSION`
-
-When defined to `1`, a JSON value can no longer be created from a one-element `std::tuple` holding a reference to a JSON
-value, such as the result of `std::forward_as_tuple(j)`. This lets `std::tuple` convert such tuples element-wise.
-
-See [full documentation of `JSON_DISABLE_TUPLE_REFERENCE_CONVERSION`](../api/macros/json_disable_tuple_reference_conversion.md).
-
 ## `JSON_NO_AUTOMATIC_UDLS`
 
 When defined, `<nlohmann/json.hpp>` does not include `<nlohmann/json_literals.hpp>` with the user-defined string literals

docs/mkdocs/docs/integration/cmake.md

@@ -169,12 +169,6 @@ Enable position diagnostics by defining macro [`JSON_DIAGNOSTIC_POSITIONS`](../a
 Disable default `enum` serialization by defining the macro
 [`JSON_DISABLE_ENUM_SERIALIZATION`](../api/macros/json_disable_enum_serialization.md). This option is `OFF` by default.
 
-### `JSON_DisableTupleReferenceConversion`
-
-Disable the conversion from a one-element `std::tuple` holding a reference to a JSON value by defining the macro
-[`JSON_DISABLE_TUPLE_REFERENCE_CONVERSION`](../api/macros/json_disable_tuple_reference_conversion.md). This option is
-`OFF` by default.
-
 ### `JSON_FastTests`
 
 Skip expensive/slow test suites. This option is `OFF` by default. Depends on `JSON_BuildTests`.

docs/mkdocs/mkdocs.yml

@@ -287,7 +287,6 @@ nav:
           - 'JSON_DIAGNOSTICS': api/macros/json_diagnostics.md
           - 'JSON_DIAGNOSTIC_POSITIONS': api/macros/json_diagnostic_positions.md
           - 'JSON_DISABLE_ENUM_SERIALIZATION': api/macros/json_disable_enum_serialization.md
-          - 'JSON_DISABLE_TUPLE_REFERENCE_CONVERSION': api/macros/json_disable_tuple_reference_conversion.md
           - 'JSON_HAS_CPP_11, JSON_HAS_CPP_14, JSON_HAS_CPP_17, JSON_HAS_CPP_20': api/macros/json_has_cpp_11.md
           - 'JSON_HAS_EXPERIMENTAL_FILESYSTEM, JSON_HAS_FILESYSTEM': api/macros/json_has_filesystem.md
           - 'JSON_HAS_RANGES': api/macros/json_has_ranges.md

include/nlohmann/detail/conversions/from_json.hpp

@@ -27,7 +27,6 @@
 #include <nlohmann/detail/meta/identity_tag.hpp>
 #include <nlohmann/detail/meta/std_fs.hpp>
 #include <nlohmann/detail/meta/type_traits.hpp>
-#include <nlohmann/detail/meta/logic.hpp>
 #include <nlohmann/detail/string_concat.hpp>
 #include <nlohmann/detail/value_t.hpp>
 
@@ -211,62 +210,29 @@ inline void from_json(const BasicJsonType& j, std::valarray<T>& l)
     });
 }
 
+// element is not itself a C array: read it directly
+template<typename BasicJsonType, typename T>
+auto from_json_c_array_element(const BasicJsonType& j, T& e)
+-> decltype(e = j.template get<T>(), void())
+{
+    e = j.template get<T>();
+}
+
+// element is itself a C array: recurse one dimension at a time, so any rank is supported
 template<typename BasicJsonType, typename T, std::size_t N>
-auto from_json(const BasicJsonType& j, T (&arr)[N])  // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
--> decltype(j.template get<T>(), void())
+void from_json_c_array_element(const BasicJsonType& j, T (&arr)[N])  // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
 {
     for (std::size_t i = 0; i < N; ++i)
     {
-        arr[i] = j.at(i).template get<T>();
+        from_json_c_array_element(j.at(i), arr[i]);
     }
 }
 
-template<typename BasicJsonType, typename T, std::size_t N1, std::size_t N2>
-auto from_json(const BasicJsonType& j, T (&arr)[N1][N2])  // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
--> decltype(j.template get<T>(), void())
+template<typename BasicJsonType, typename T, std::size_t N>
+auto from_json(const BasicJsonType& j, T (&arr)[N])  // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
+-> decltype(j.template get<typename std::remove_all_extents<T>::type>(), void())
 {
-    for (std::size_t i1 = 0; i1 < N1; ++i1)
-    {
-        for (std::size_t i2 = 0; i2 < N2; ++i2)
-        {
-            arr[i1][i2] = j.at(i1).at(i2).template get<T>();
-        }
-    }
-}
-
-template<typename BasicJsonType, typename T, std::size_t N1, std::size_t N2, std::size_t N3>
-auto from_json(const BasicJsonType& j, T (&arr)[N1][N2][N3])  // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
--> decltype(j.template get<T>(), void())
-{
-    for (std::size_t i1 = 0; i1 < N1; ++i1)
-    {
-        for (std::size_t i2 = 0; i2 < N2; ++i2)
-        {
-            for (std::size_t i3 = 0; i3 < N3; ++i3)
-            {
-                arr[i1][i2][i3] = j.at(i1).at(i2).at(i3).template get<T>();
-            }
-        }
-    }
-}
-
-template<typename BasicJsonType, typename T, std::size_t N1, std::size_t N2, std::size_t N3, std::size_t N4>
-auto from_json(const BasicJsonType& j, T (&arr)[N1][N2][N3][N4])  // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
--> decltype(j.template get<T>(), void())
-{
-    for (std::size_t i1 = 0; i1 < N1; ++i1)
-    {
-        for (std::size_t i2 = 0; i2 < N2; ++i2)
-        {
-            for (std::size_t i3 = 0; i3 < N3; ++i3)
-            {
-                for (std::size_t i4 = 0; i4 < N4; ++i4)
-                {
-                    arr[i1][i2][i3][i4] = j.at(i1).at(i2).at(i3).at(i4).template get<T>();
-                }
-            }
-        }
-    }
+    from_json_c_array_element(j, arr);
 }
 
 template<typename BasicJsonType>
@@ -286,20 +252,33 @@ auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
     }
 }
 
+// reserve() is called through this pair (modeled on from_json_object_reserve)
+// so from_json_array_impl below has a single body for both ConstructibleArrayType
+// that support reserve() and those that don't.
+template<typename ConstructibleArrayType>
+auto from_json_array_reserve(ConstructibleArrayType& arr, typename ConstructibleArrayType::size_type size, priority_tag<1> /*unused*/)
+-> decltype(arr.reserve(size), void())
+{
+    arr.reserve(size);
+}
+
+template<typename ConstructibleArrayType>
+inline void from_json_array_reserve(ConstructibleArrayType& /*arr*/, std::size_t /*size*/, priority_tag<0> /*unused*/)
+{}
+
 template<typename BasicJsonType, typename ConstructibleArrayType,
          enable_if_t<
              std::is_assignable<ConstructibleArrayType&, ConstructibleArrayType>::value,
              int> = 0>
 auto from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr, priority_tag<1> /*unused*/)
 -> decltype(
-    arr.reserve(std::declval<typename ConstructibleArrayType::size_type>()),
     j.template get<typename ConstructibleArrayType::value_type>(),
     void())
 {
     using std::end;
 
     ConstructibleArrayType ret;
-    ret.reserve(j.size());
+    from_json_array_reserve(ret, j.size(), priority_tag<1> {});
     std::transform(j.begin(), j.end(),
                    std::inserter(ret, end(ret)), [](const BasicJsonType & i)
     {
@@ -310,27 +289,6 @@ auto from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr, p
     arr = std::move(ret);
 }
 
-template<typename BasicJsonType, typename ConstructibleArrayType,
-         enable_if_t<
-             std::is_assignable<ConstructibleArrayType&, ConstructibleArrayType>::value,
-             int> = 0>
-inline void from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr,
-                                 priority_tag<0> /*unused*/)
-{
-    using std::end;
-
-    ConstructibleArrayType ret;
-    std::transform(
-        j.begin(), j.end(), std::inserter(ret, end(ret)),
-        [](const BasicJsonType & i)
-    {
-        // get<BasicJsonType>() returns *this, this won't call a from_json
-        // method when value_type is BasicJsonType
-        return i.template get<typename ConstructibleArrayType::value_type>();
-    });
-    arr = std::move(ret);
-}
-
 template < typename BasicJsonType, typename ConstructibleArrayType,
            enable_if_t <
                is_constructible_array_type<BasicJsonType, ConstructibleArrayType>::value&&
@@ -433,9 +391,7 @@ inline void from_json(const BasicJsonType& j, ConstructibleObjectType& obj)
 }
 
 // overload for arithmetic types, not chosen for basic_json template arguments
-// (BooleanType, etc.); note: Is it really necessary to provide explicit
-// overloads for boolean_t etc. in case of a custom BooleanType which is not
-// an arithmetic type?
+// (BooleanType, etc.)
 template < typename BasicJsonType, typename ArithmeticType,
            enable_if_t <
                std::is_arithmetic<ArithmeticType>::value&&
@@ -531,7 +487,7 @@ inline void from_json_tuple_impl(BasicJsonType&& j, std::pair<A1, A2>& p, priori
 template<typename BasicJsonType, typename... Args>
 std::tuple<Args...> from_json_tuple_impl(BasicJsonType&& j, identity_tag<std::tuple<Args...>> /*unused*/, priority_tag<2> /*unused*/)
 {
-    static_assert(cxpr_and<cxpr_or<cxpr_not<std::is_reference<Args>>, is_compatible_reference_type<BasicJsonType, Args>>...>::value,
+    static_assert(conjunction<disjunction<negation<std::is_reference<Args>>, is_compatible_reference_type<BasicJsonType, Args>>...>::value,
                   "Can not return a tuple containing references to types not contained in a Json, try Json::get_to()");
     return from_json_tuple_impl_base<1, Args...>(std::forward<BasicJsonType>(j), index_sequence_for<Args...> {});
 }
@@ -554,10 +510,10 @@ auto from_json(BasicJsonType&& j, TupleRelated&& t)
     return from_json_tuple_impl(std::forward<BasicJsonType>(j), std::forward<TupleRelated>(t), priority_tag<3> {});
 }
 
-template < typename BasicJsonType, typename Key, typename Value, typename Compare, typename Allocator,
-           typename = enable_if_t < !std::is_constructible <
-                                        typename BasicJsonType::string_t, Key >::value >>
-inline void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allocator>& m)
+// shared body for std::map/std::unordered_map with a non-string Key: both
+// containers are read from an array of [key, value] pairs the same way
+template<typename BasicJsonType, typename MapType>
+inline void from_json_pair_array_to_map(const BasicJsonType& j, MapType& m)
 {
     if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
     {
@@ -570,33 +526,29 @@ inline void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allo
         {
             JSON_THROW(type_error::create(302, concat("type must be array, but is ", p.type_name()), &p));
         }
-        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
+        m.emplace(p.at(0).template get<typename MapType::key_type>(), p.at(1).template get<typename MapType::mapped_type>());
     }
 }
 
+template < typename BasicJsonType, typename Key, typename Value, typename Compare, typename Allocator,
+           typename = enable_if_t < !std::is_constructible <
+                                        typename BasicJsonType::string_t, Key >::value >>
+inline void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allocator>& m)
+{
+    from_json_pair_array_to_map(j, m);
+}
+
 template < typename BasicJsonType, typename Key, typename Value, typename Hash, typename KeyEqual, typename Allocator,
            typename = enable_if_t < !std::is_constructible <
                                         typename BasicJsonType::string_t, Key >::value >>
 inline void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyEqual, Allocator>& m)
 {
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, concat("type must be array, but is ", j.type_name()), &j));
-    }
-    m.clear();
-    for (const auto& p : j)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!p.is_array()))
-        {
-            JSON_THROW(type_error::create(302, concat("type must be array, but is ", p.type_name()), &p));
-        }
-        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
-    }
+    from_json_pair_array_to_map(j, m);
 }
 
 #if JSON_HAS_FILESYSTEM || JSON_HAS_EXPERIMENTAL_FILESYSTEM
 
-// Workaround for MSVC 19.51 (and possibly later): in large in large cpp files, the compiler may fail to resolve with generic has_from_json (issue #4996)
+// Workaround for MSVC 19.51 (and possibly later): in large cpp files, the compiler may fail to resolve with generic has_from_json (issue #4996)
 template<typename BasicJsonType>
 struct has_from_json<BasicJsonType, std_fs::path, void> : std::true_type {};
 

include/nlohmann/detail/conversions/to_json.hpp

@@ -178,7 +178,7 @@ struct external_constructor<value_t::array>
 
     template < typename BasicJsonType, typename CompatibleArrayType,
                enable_if_t < !std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
                              && !is_compatible_range_view<CompatibleArrayType>::value
 #endif
                              , int > = 0 >
@@ -222,9 +222,7 @@ struct external_constructor<value_t::array>
         j.assert_invariant();
     }
 
-    // std::ranges does not work properly on MinGW due to incomplete C++20 support
-    // see https://github.com/nlohmann/json/issues/4916
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
     template<typename BasicJsonType, typename CompatibleArrayType,
              enable_if_t<is_compatible_range_view<std::remove_cvref_t<CompatibleArrayType>>::value, int> = 0>
     static void construct(BasicJsonType& j, CompatibleArrayType && arr)
@@ -379,7 +377,7 @@ template < typename BasicJsonType, typename CompatibleArrayType,
                          !std::is_same<typename BasicJsonType::binary_t, CompatibleArrayType>::value&&
                          !is_compatible_binary_type<BasicJsonType, CompatibleArrayType>::value&&
                          !is_basic_json<CompatibleArrayType>::value
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
     && !is_compatible_range_view<CompatibleArrayType>::value
 #endif
                          ,
@@ -389,7 +387,7 @@ inline void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
     external_constructor<value_t::array>::construct(j, arr);
 }
 
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
 template < typename BasicJsonType, typename T,
            enable_if_t < is_compatible_range_view<std::remove_cvref_t<T>>::value
                          && !is_compatible_string_type<BasicJsonType, std::remove_cvref_t<T>>::value
@@ -471,13 +469,11 @@ inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<
     j = { std::get<Idx>(t)... };
 }
 
-// A one-element braced list does not reliably wrap its element: with
-// JSON_BRACE_INIT_COPY_SEMANTICS it copies it, which would serialize
-// std::tuple<int>{5} as 5 rather than [5], and some compilers (e.g., Apple clang
-// 15 and 16) copy an element that is itself a basic_json even without it, so
-// std::tuple<json>{true} became true rather than [true]. Build what the default
-// deduction builds instead: an object if the element is a [string, value] pair,
-// a one-element array otherwise.
+#if JSON_BRACE_INIT_COPY_SEMANTICS
+// JSON_BRACE_INIT_COPY_SEMANTICS makes a one-element braced list copy its
+// element instead of wrapping it, which would serialize std::tuple<int>{5} as 5
+// rather than [5]. Build what the default deduction builds instead: an object
+// if the element is a [string, value] pair, a one-element array otherwise.
 template<typename BasicJsonType, typename Tuple>
 inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<0> /*unused*/)
 {
@@ -495,6 +491,7 @@ inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<
         j = BasicJsonType::array({std::move(element)});
     }
 }
+#endif
 
 template<typename BasicJsonType, typename Tuple>
 inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& /*unused*/, index_sequence<> /*unused*/)

include/nlohmann/detail/exceptions.hpp

@@ -286,6 +286,27 @@ class other_error : public exception
     other_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
 };
 
+/*!
+@brief helper function to call JSON_THROW from a template
+@note JSON_THROW is a macro that, depending on the JSON_THROW_USER /
+      JSON_TRY_USER / JSON_NOEXCEPTION configuration, may expand to code
+      that does not reference its argument (e.g. `std::abort()`), which
+      would trigger a compilation error if the argument's type depends on
+      a template parameter that is otherwise unused. Wrapping the call in
+      a templated function avoids this and gives the compiler a single
+      place to see the (possibly unused) parameter.
+*/
+template<typename ExceptionType>
+void templated_json_throw(ExceptionType exception)
+{
+    JSON_THROW(exception);
+
+    // JSON_THROW may expand to code that discards its argument (e.g. when
+    // exceptions are disabled) - the cast below avoids an unused-parameter
+    // warning with -Werror in that case
+    (void)exception;
+}
+
 }  // namespace detail
 NLOHMANN_JSON_NAMESPACE_END
 

include/nlohmann/detail/input/binary_reader.hpp

@@ -4111,16 +4111,12 @@ class binary_reader
             return false;
         }
 
-        // RFC 8949 (CBOR) §3.1 and the BSON/UBJSON specifications require
-        // text strings to be valid UTF-8; reject anything else right here so
-        // malformed input is caught at decode time instead of only surfacing
-        // later as a type_error.316 when the value is dumped (which would
-        // defeat allow_exceptions=false / strict discarding). The MessagePack
-        // specification explicitly allows a str object to contain an invalid
-        // byte sequence and expects deserializers to hand back the original
-        // bytes, so msgpack strings (and map keys, which go through this
-        // function as well) are exempt.
-        if (format != input_format_t::msgpack && JSON_HEDLEY_UNLIKELY(!is_valid_utf8(result, old_size)))
+        // RFC 8949 (CBOR) §3.1 and the MessagePack/BSON/UBJSON specifications
+        // all require text strings to be valid UTF-8; reject anything else
+        // right here so malformed input is caught at decode time instead of
+        // only surfacing later as a type_error.316 when the value is dumped
+        // (which would defeat allow_exceptions=false / strict discarding).
+        if (JSON_HEDLEY_UNLIKELY(!is_valid_utf8(result, old_size)))
         {
             return sax->parse_error(chars_read, get_token_string(),
                                     parse_error::create(113, chars_read,

include/nlohmann/detail/iterators/iter_impl.hpp

@@ -60,9 +60,11 @@ class iter_impl // NOLINT(cppcoreguidelines-special-member-functions,hicpp-speci
     static_assert(is_basic_json<typename std::remove_const<BasicJsonType>::type>::value,
                   "iter_impl only accepts (const) basic_json");
     // superficial check for the LegacyBidirectionalIterator named requirement
-    static_assert(std::is_base_of<std::bidirectional_iterator_tag, std::bidirectional_iterator_tag>::value
-                  &&  std::is_base_of<std::bidirectional_iterator_tag, typename std::iterator_traits<typename array_t::iterator>::iterator_category>::value,
-                  "basic_json iterator assumes array and object type iterators satisfy the LegacyBidirectionalIterator named requirement.");
+    // note: only array_t::iterator is checked here; object_t::iterator may be
+    // a forward-only iterator as long as reverse iteration and operator--
+    // are never used on it
+    static_assert(std::is_base_of<std::bidirectional_iterator_tag, typename std::iterator_traits<typename array_t::iterator>::iterator_category>::value,
+                  "basic_json iterator assumes array type iterators satisfy the LegacyBidirectionalIterator named requirement.");
 
   public:
     /// The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17.

include/nlohmann/detail/json_pointer.hpp

@@ -240,6 +240,72 @@ class json_pointer
     }
 
   private:
+    /*!
+    @brief result of @ref parse_array_index
+
+    @ref array_index maps each value to the corresponding parse_error/out_of_range
+    exception; @ref contains and @ref get_checked_or_null, which must not throw for
+    an out-of-range or unrepresentable index, switch on it directly instead.
+    */
+    enum class array_index_status
+    {
+        ok,                ///< @a s is a valid, representable array index
+        leading_zero,      ///< @a s begins with '0' but has more than one character
+        not_a_number,      ///< @a s does not begin with a digit
+        unresolved,        ///< @a s could not be converted to an integer
+        exceeds_size_type  ///< @a s converts to an integer that exceeds size_type
+    };
+
+    /*!
+    @param[in] s    reference token to be converted into an array index
+    @param[out] idx the integer representation of @a s if @ref array_index_status::ok
+                     is returned; left unchanged otherwise
+
+    @return whether @a s is a valid array index, and if not, why
+
+    @note this function never throws; @ref array_index and the callers that must not
+          throw (@ref contains, @ref get_checked_or_null) build on it instead of each
+          re-implementing the RFC 6901 digit rules and the @a size_type range check
+    */
+    template<typename BasicJsonType>
+    static array_index_status parse_array_index(const string_t& s, typename BasicJsonType::size_type& idx) noexcept
+    {
+        using size_type = typename BasicJsonType::size_type;
+
+        // error condition (cf. RFC 6901, Sect. 4)
+        if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && s[0] == '0'))
+        {
+            return array_index_status::leading_zero;
+        }
+
+        // error condition (cf. RFC 6901, Sect. 4)
+        if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && !(s[0] >= '1' && s[0] <= '9')))
+        {
+            return array_index_status::not_a_number;
+        }
+
+        const char* p = s.data();
+        char* p_end = nullptr; // NOLINT(misc-const-correctness)
+        errno = 0; // strtoull doesn't reset errno
+        const unsigned long long res = std::strtoull(p, &p_end, 10); // NOLINT(runtime/int)
+        if (p == p_end // invalid input or empty string
+                || errno == ERANGE // out of range
+                || JSON_HEDLEY_UNLIKELY(static_cast<std::size_t>(p_end - p) != s.size())) // incomplete read
+        {
+            return array_index_status::unresolved;
+        }
+
+        // only triggered on special platforms (like 32bit), see also
+        // https://github.com/nlohmann/json/pull/2203
+        if (res >= static_cast<unsigned long long>((std::numeric_limits<size_type>::max)()))  // NOLINT(runtime/int)
+        {
+            return array_index_status::exceeds_size_type;   // LCOV_EXCL_LINE
+        }
+
+        idx = static_cast<size_type>(res);
+        return array_index_status::ok;
+    }
+
     /*!
     @param[in] s  reference token to be converted into an array index
 
@@ -253,39 +319,30 @@ class json_pointer
     template<typename BasicJsonType>
     static typename BasicJsonType::size_type array_index(const string_t& s)
     {
-        using size_type = typename BasicJsonType::size_type;
+        typename BasicJsonType::size_type idx{};
+        const auto status = parse_array_index<BasicJsonType>(s, idx);
 
-        // error condition (cf. RFC 6901, Sect. 4)
-        if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && s[0] == '0'))
+        if (JSON_HEDLEY_UNLIKELY(status == array_index_status::leading_zero))
         {
             JSON_THROW(detail::parse_error::create(106, 0, detail::concat("array index '", s, "' must not begin with '0'"), nullptr));
         }
 
-        // error condition (cf. RFC 6901, Sect. 4)
-        if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && !(s[0] >= '1' && s[0] <= '9')))
+        if (JSON_HEDLEY_UNLIKELY(status == array_index_status::not_a_number))
         {
             JSON_THROW(detail::parse_error::create(109, 0, detail::concat("array index '", s, "' is not a number"), nullptr));
         }
 
-        const char* p = s.data();
-        char* p_end = nullptr; // NOLINT(misc-const-correctness)
-        errno = 0; // strtoull doesn't reset errno
-        const unsigned long long res = std::strtoull(p, &p_end, 10); // NOLINT(runtime/int)
-        if (p == p_end // invalid input or empty string
-                || errno == ERANGE // out of range
-                || JSON_HEDLEY_UNLIKELY(static_cast<std::size_t>(p_end - p) != s.size())) // incomplete read
+        if (JSON_HEDLEY_UNLIKELY(status == array_index_status::unresolved))
         {
             JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", s, "'"), nullptr));
         }
 
-        // only triggered on special platforms (like 32bit), see also
-        // https://github.com/nlohmann/json/pull/2203
-        if (res >= static_cast<unsigned long long>((std::numeric_limits<size_type>::max)()))  // NOLINT(runtime/int)
+        if (JSON_HEDLEY_UNLIKELY(status == array_index_status::exceeds_size_type))
         {
             JSON_THROW(detail::out_of_range::create(410, detail::concat("array index ", s, " exceeds size_type"), nullptr));   // LCOV_EXCL_LINE
         }
 
-        return static_cast<size_type>(res);
+        return idx;
     }
 
   JSON_PRIVATE_UNLESS_TESTED:
@@ -584,63 +641,6 @@ class json_pointer
         return *ptr;
     }
 
-    /*!
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.402  if the array index '-' is used
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-    */
-    template<typename BasicJsonType>
-    const BasicJsonType& get_checked(const BasicJsonType* ptr) const
-    {
-        for (const auto& reference_token : reference_tokens)
-        {
-            switch (ptr->type())
-            {
-                case detail::value_t::object:
-                {
-                    // note: at performs range check
-                    ptr = &ptr->at(reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
-                    {
-                        // "-" always fails the range check
-                        JSON_THROW(detail::out_of_range::create(402, detail::concat(
-                                "array index '-' (", std::to_string(ptr->m_data.m_value.array->size()),
-                                ") is out of range"), ptr));
-                    }
-
-                    const auto idx = array_index<BasicJsonType>(reference_token);
-                    // Bounds check before access to avoid exception with JSON_NOEXCEPTION
-                    if (JSON_HEDLEY_UNLIKELY(idx >= ptr->m_data.m_value.array->size()))
-                    {
-                        JSON_THROW(detail::out_of_range::create(401, detail::concat(
-                                "array index ", std::to_string(idx), " is out of range"), ptr));
-                    }
-                    ptr = &ptr->operator[](idx);
-                    break;
-                }
-
-                case detail::value_t::null:
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                    JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", reference_token, "'"), ptr));
-            }
-        }
-
-        return *ptr;
-    }
-
     /*!
     @brief return a pointer to the pointed to value, or `nullptr` if the
            pointer cannot be resolved because a key is missing, an array
@@ -679,18 +679,23 @@ class json_pointer
                         return nullptr;
                     }
 
-                    // may throw parse_error.106/109 for a malformed index; an
+                    // a malformed index still throws parse_error.106/109; an
                     // index that is syntactically valid but cannot be
                     // represented (out_of_range.404/410) is treated like an
                     // out-of-range index below
                     typename BasicJsonType::size_type idx{};
-                    JSON_TRY
+                    switch (parse_array_index<BasicJsonType>(reference_token, idx))
                     {
-                        idx = array_index<BasicJsonType>(reference_token);
-                    }
-                    JSON_INTERNAL_CATCH (detail::out_of_range&)
-                    {
-                        return nullptr;
+                        case array_index_status::leading_zero:
+                            JSON_THROW(detail::parse_error::create(106, 0, detail::concat("array index '", reference_token, "' must not begin with '0'"), nullptr));
+                        case array_index_status::not_a_number:
+                            JSON_THROW(detail::parse_error::create(109, 0, detail::concat("array index '", reference_token, "' is not a number"), nullptr));
+                        case array_index_status::unresolved:
+                        case array_index_status::exceeds_size_type:
+                            return nullptr;
+                        case array_index_status::ok:
+                        default:
+                            break;
                     }
 
                     if (JSON_HEDLEY_UNLIKELY(idx >= ptr->m_data.m_value.array->size()))
@@ -718,8 +723,8 @@ class json_pointer
     }
 
     /*!
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
+    @note unlike array_index(), this never throws: a malformed or unrepresentable
+          array index reference token is treated like a missing key (see #5395)
     */
     template<typename BasicJsonType>
     bool contains(const BasicJsonType* ptr) const
@@ -747,49 +752,17 @@ class json_pointer
                         // "-" always fails the range check
                         return false;
                     }
-                    if (JSON_HEDLEY_UNLIKELY(reference_token.empty()))
-                    {
-                        // an empty reference token is not an array index; array_index()
-                        // would throw out_of_range.404 -- contains() must not throw (see #5395)
-                        return false;
-                    }
-                    if (JSON_HEDLEY_UNLIKELY(reference_token.size() == 1 && !('0' <= reference_token[0] && reference_token[0] <= '9')))
-                    {
-                        // invalid char
-                        return false;
-                    }
-                    if (JSON_HEDLEY_UNLIKELY(reference_token.size() > 1))
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!('1' <= reference_token[0] && reference_token[0] <= '9')))
-                        {
-                            // the first char should be between '1' and '9'
-                            return false;
-                        }
-                        for (std::size_t i = 1; i < reference_token.size(); i++)
-                        {
-                            if (JSON_HEDLEY_UNLIKELY(!('0' <= reference_token[i] && reference_token[i] <= '9')))
-                            {
-                                // other char should be between '0' and '9'
-                                return false;
-                            }
-                        }
-                    }
 
-                    // the reference token consists only of digits at this point (cf. checks
-                    // above); however, its numeric value might not be representable, in which
-                    // case array_index() would throw out_of_range.404/410 -- contains() must
-                    // not throw (see #5395), so such a reference token is treated as "not found"
-                    errno = 0; // strtoull() does not reset errno on success
-                    char* p_end = nullptr; // NOLINT(misc-const-correctness)
-                    const unsigned long long magnitude = std::strtoull(reference_token.data(), &p_end, 10); // NOLINT(runtime/int)
-                    if (JSON_HEDLEY_UNLIKELY(errno == ERANGE // the value exceeds ULLONG_MAX
-                                             || magnitude >= static_cast<unsigned long long>((std::numeric_limits<typename BasicJsonType::size_type>::max)()))) // NOLINT(runtime/int)
+                    // any parse failure (malformed index, or one that is syntactically
+                    // valid but not representable as size_type) means the reference
+                    // token cannot denote an existing array element -- contains() must
+                    // not throw (see #5395), so it is treated as "not found"
+                    typename BasicJsonType::size_type idx{};
+                    if (JSON_HEDLEY_UNLIKELY(parse_array_index<BasicJsonType>(reference_token, idx) != array_index_status::ok))
                     {
-                        // the array index cannot be represented as size_type
                         return false;
                     }
 
-                    const auto idx = array_index<BasicJsonType>(reference_token);
                     if (idx >= ptr->size())
                     {
                         // index out of range

include/nlohmann/detail/macro_scope.hpp

@@ -9,7 +9,6 @@
 #pragma once
 
 #include <utility> // declval, pair
-#include <nlohmann/detail/meta/detected.hpp>
 #include <nlohmann/thirdparty/hedley/hedley.hpp>
 
 // This file contains all internal macro definitions (except those affecting ABI)
@@ -140,10 +139,12 @@
         // libstdc++ < 11 has incomplete C++20 ranges (issue #4440)
     #elif defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE < 11
         #define JSON_HAS_RANGES 0
-        // libc++ < 16 has incomplete C++20 ranges (issue #4440)
+        // clang < 16 with libstdc++ does not implement the ranges customization
+        // points libstdc++ declares, so its C++20 ranges support is incomplete (issue #5161)
     #elif defined(__clang__) && !defined(__apple_build_version__) \
         && __clang_major__ < 16 && defined(__GLIBCXX__)
         #define JSON_HAS_RANGES 0
+        // libc++ < 16 has incomplete C++20 ranges (issue #4440)
     #elif defined(_LIBCPP_VERSION) && _LIBCPP_VERSION < 160000
         #define JSON_HAS_RANGES 0
         // nvcc CUDA 12.0/12.1 chokes on the enable_borrowed_range variable-template
@@ -158,6 +159,18 @@
     #endif
 #endif
 
+// std::ranges view conversion (to_json/is_compatible_array_type_impl) additionally
+// needs to be disabled on MinGW, whose std::ranges support is incomplete
+// (issue #4916); this macro combines both conditions so the check and its
+// reason are not duplicated at every use site.
+#ifndef JSON_HAS_RANGE_VIEW_CONVERSION
+    #if JSON_HAS_RANGES && !defined(__MINGW32__)
+        #define JSON_HAS_RANGE_VIEW_CONVERSION 1
+    #else
+        #define JSON_HAS_RANGE_VIEW_CONVERSION 0
+    #endif
+#endif
+
 #ifndef JSON_HAS_STD_FORMAT
     #if defined(JSON_HAS_CPP_20) && defined(__cpp_lib_format)
         #define JSON_HAS_STD_FORMAT 1
@@ -286,26 +299,11 @@
 
 
 
-/*!
-@brief function to wrap JSON_THROW_MACRO - there can be compilation errors about
-       there being no arguments to JSON_THROW that depend on template arguments
-       if this is not used to call JSON_THROW
-*/
-template<typename ExceptionType>
-void templated_json_throw(ExceptionType exception)
-{
-    JSON_THROW(exception);
-
-    /* JSON_THROW(exception) discards exception and aborts - void cast needed to supress
-       compilation error if compiled with -Werror and Wunused-parameter */
-    (void)exception;
-}
-
 /*!
 @brief macro to briefly define a mapping between an enum and JSON with exception
        on invalid input
 @def NLOHMANN_JSON_SERIALIZE_ENUM_STRICT
-@since version 3.12.0
+@since version 3.13.0
 */
 #define NLOHMANN_JSON_SERIALIZE_ENUM_STRICT(ENUM_TYPE, ...)                                     \
     template<typename BasicJsonType>                                                            \
@@ -321,7 +319,7 @@ void templated_json_throw(ExceptionType exception)
             return ej_pair.first == e;                                                          \
         });                                                                                     \
         if (it != std::end(m)) j = it->second;                                                  \
-        else templated_json_throw<nlohmann::detail::out_of_range>(nlohmann::detail::out_of_range::create(410,"enum value out of range for " #ENUM_TYPE, nullptr)); \
+        else ::nlohmann::detail::templated_json_throw<nlohmann::detail::out_of_range>(nlohmann::detail::out_of_range::create(410,"enum value out of range for " #ENUM_TYPE, nullptr)); \
     }                                                                                           \
     template<typename BasicJsonType>                                                            \
     inline void from_json(const BasicJsonType& j, ENUM_TYPE& e)                                 \
@@ -336,7 +334,7 @@ void templated_json_throw(ExceptionType exception)
             return ej_pair.second == j;                                                         \
         });                                                                                     \
         if (it != std::end(m)) e = it->first;                                                   \
-        else templated_json_throw<nlohmann::detail::out_of_range>(nlohmann::detail::out_of_range::create(410, nlohmann::detail::concat("enum value out of range for " #ENUM_TYPE ": ", j.dump(-1, ' ', false, nlohmann::detail::error_handler_t::replace)), &j)); \
+        else ::nlohmann::detail::templated_json_throw<nlohmann::detail::out_of_range>(nlohmann::detail::out_of_range::create(410, nlohmann::detail::concat("enum value out of range for " #ENUM_TYPE ": ", j.dump(-1, ' ', false, nlohmann::detail::error_handler_t::replace)), &j)); \
     }
 
 // Ugly macros to avoid uglier copy-paste when specializing basic_json. They
@@ -876,30 +874,6 @@ void templated_json_throw(ExceptionType exception)
     \
     template<typename... T>                                                       \
     using result_of_##std_name = decltype(std_name(std::declval<T>()...));        \
-    }                                                                             \
-    \
-    namespace detail2 {                                                           \
-    struct std_name##_tag                                                         \
-    {                                                                             \
-    };                                                                            \
-    \
-    template<typename... T>                                                       \
-    std_name##_tag std_name(T&&...);                                              \
-    \
-    template<typename... T>                                                       \
-    using result_of_##std_name = decltype(std_name(std::declval<T>()...));        \
-    \
-    template<typename... T>                                                       \
-    struct would_call_std_##std_name                                              \
-    {                                                                             \
-        static constexpr auto const value = ::nlohmann::detail::                  \
-                                            is_detected_exact<std_name##_tag, result_of_##std_name, T...>::value; \
-    };                                                                            \
-    } /* namespace detail2 */ \
-    \
-    template<typename... T>                                                       \
-    struct would_call_std_##std_name : detail2::would_call_std_##std_name<T...>   \
-    {                                                                             \
     }
 
 #ifndef JSON_USE_IMPLICIT_CONVERSIONS
@@ -915,7 +889,3 @@ void templated_json_throw(ExceptionType exception)
 #ifndef JSON_DISABLE_ENUM_SERIALIZATION
     #define JSON_DISABLE_ENUM_SERIALIZATION 0
 #endif
-
-#ifndef JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-    #define JSON_DISABLE_TUPLE_REFERENCE_CONVERSION 0
-#endif

include/nlohmann/detail/macro_unscope.hpp

@@ -25,7 +25,6 @@
 #undef JSON_INLINE_VARIABLE
 #undef JSON_NO_UNIQUE_ADDRESS
 #undef JSON_DISABLE_ENUM_SERIALIZATION
-#undef JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
 
 #ifndef JSON_TEST_KEEP_MACROS
     #undef JSON_CATCH
@@ -40,6 +39,7 @@
     #undef JSON_HAS_EXPERIMENTAL_FILESYSTEM
     #undef JSON_HAS_THREE_WAY_COMPARISON
     #undef JSON_HAS_RANGES
+    #undef JSON_HAS_RANGE_VIEW_CONVERSION
     #undef JSON_HAS_STD_FORMAT
     #undef JSON_HAS_STATIC_RTTI
     #undef JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON

include/nlohmann/detail/meta/call_std/begin.hpp

@@ -12,6 +12,6 @@
 
 NLOHMANN_JSON_NAMESPACE_BEGIN
 
-NLOHMANN_CAN_CALL_STD_FUNC_IMPL(begin);
+NLOHMANN_CAN_CALL_STD_FUNC_IMPL(begin)
 
 NLOHMANN_JSON_NAMESPACE_END

include/nlohmann/detail/meta/call_std/end.hpp

@@ -12,6 +12,6 @@
 
 NLOHMANN_JSON_NAMESPACE_BEGIN
 
-NLOHMANN_CAN_CALL_STD_FUNC_IMPL(end);
+NLOHMANN_CAN_CALL_STD_FUNC_IMPL(end)
 
 NLOHMANN_JSON_NAMESPACE_END

include/nlohmann/detail/meta/detected.hpp

@@ -62,9 +62,5 @@ using detected_or_t = typename detected_or<Default, Op, Args...>::type;
 template<class Expected, template<class...> class Op, class... Args>
 using is_detected_exact = std::is_same<Expected, detected_t<Op, Args...>>;
 
-template<class To, template<class...> class Op, class... Args>
-using is_detected_convertible =
-    std::is_convertible<detected_t<Op, Args...>, To>;
-
 }  // namespace detail
 NLOHMANN_JSON_NAMESPACE_END

include/nlohmann/detail/meta/is_sax.hpp

@@ -8,7 +8,7 @@
 
 #pragma once
 
-#include <cstdint> // size_t
+#include <cstddef> // size_t
 #include <utility> // declval
 #include <string> // string
 
@@ -70,37 +70,6 @@ using parse_error_function_t = decltype(std::declval<T&>().parse_error(
         std::declval<std::size_t>(), std::declval<const std::string&>(),
         std::declval<const Exception&>()));
 
-template<typename SAX, typename BasicJsonType>
-struct is_sax
-{
-  private:
-    static_assert(is_basic_json<BasicJsonType>::value,
-                  "BasicJsonType must be of type basic_json<...>");
-
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-    using exception_t = typename BasicJsonType::exception;
-
-  public:
-    static constexpr bool value =
-        is_detected_exact<bool, null_function_t, SAX>::value &&
-        is_detected_exact<bool, boolean_function_t, SAX>::value &&
-        is_detected_exact<bool, number_integer_function_t, SAX, number_integer_t>::value &&
-        is_detected_exact<bool, number_unsigned_function_t, SAX, number_unsigned_t>::value &&
-        is_detected_exact<bool, number_float_function_t, SAX, number_float_t, string_t>::value &&
-        is_detected_exact<bool, string_function_t, SAX, string_t>::value &&
-        is_detected_exact<bool, binary_function_t, SAX, binary_t>::value &&
-        is_detected_exact<bool, start_object_function_t, SAX>::value &&
-        is_detected_exact<bool, key_function_t, SAX, string_t>::value &&
-        is_detected_exact<bool, end_object_function_t, SAX>::value &&
-        is_detected_exact<bool, start_array_function_t, SAX>::value &&
-        is_detected_exact<bool, end_array_function_t, SAX>::value &&
-        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value;
-};
-
 template<typename SAX, typename BasicJsonType>
 struct is_sax_static_asserts
 {
@@ -120,8 +89,6 @@ struct is_sax_static_asserts
                   "Missing/invalid function: bool null()");
     static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
                   "Missing/invalid function: bool boolean(bool)");
-    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
-                  "Missing/invalid function: bool boolean(bool)");
     static_assert(
         is_detected_exact<bool, number_integer_function_t, SAX,
         number_integer_t>::value,

include/nlohmann/detail/meta/logic.hpp

@@ -1,54 +0,0 @@
-#pragma once
-
-#include <nlohmann/detail/macro_scope.hpp>
-
-NLOHMANN_JSON_NAMESPACE_BEGIN
-namespace detail
-{
-#ifdef JSON_HAS_CPP_17
-
-template<bool... Booleans>
-struct cxpr_or_impl : std::integral_constant < bool, (Booleans || ...) > {};
-
-template<bool... Booleans>
-struct cxpr_and_impl : std::integral_constant < bool, (Booleans &&...) > {};
-
-#else
-
-template<bool... Booleans>
-struct cxpr_or_impl : std::false_type {};
-
-template<bool... Booleans>
-struct cxpr_or_impl<true, Booleans...> : std::true_type {};
-
-template<bool... Booleans>
-struct cxpr_or_impl<false, Booleans...> : cxpr_or_impl<Booleans...> {};
-
-template<bool... Booleans>
-struct cxpr_and_impl : std::true_type {};
-
-template<bool... Booleans>
-struct cxpr_and_impl<true, Booleans...> : cxpr_and_impl<Booleans...> {};
-
-template<bool... Booleans>
-struct cxpr_and_impl<false, Booleans...> : std::false_type {};
-
-#endif
-
-template<class Boolean>
-struct cxpr_not : std::integral_constant < bool, !Boolean::value > {};
-
-template<class... Booleans>
-struct cxpr_or : cxpr_or_impl<Booleans::value...> {};
-
-template<bool... Booleans>
-struct cxpr_or_c : cxpr_or_impl<Booleans...> {};
-
-template<class... Booleans>
-struct cxpr_and : cxpr_and_impl<Booleans::value...> {};
-
-template<bool... Booleans>
-struct cxpr_and_c : cxpr_and_impl<Booleans...> {};
-
-}  // namespace detail
-NLOHMANN_JSON_NAMESPACE_END

include/nlohmann/detail/meta/type_traits.hpp

@@ -283,6 +283,13 @@ template<class B, class... Bn>
 struct conjunction<B, Bn...>
 : std::conditional<static_cast<bool>(B::value), conjunction<Bn...>, B>::type {};
 
+// https://en.cppreference.com/w/cpp/types/disjunction
+template<class...> struct disjunction : std::false_type { };
+template<class B> struct disjunction<B> : B { };
+template<class B, class... Bn>
+struct disjunction<B, Bn...>
+: std::conditional<static_cast<bool>(B::value), B, disjunction<Bn...>>::type {};
+
 // https://en.cppreference.com/w/cpp/types/negation
 template<class B> struct negation : std::integral_constant < bool, !B::value > { };
 
@@ -477,9 +484,7 @@ template<typename T> struct is_range_view_optional_type<std::optional<T>> : std:
 template<typename T> struct is_range_view_optional_type : std::false_type {};
 #endif
 
-// std::ranges does not work properly on MinGW due to incomplete C++20 support
-// see https://github.com/nlohmann/json/issues/4916
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
 
 // SafeToCheck guards against types that trigger circular constraints when
 // std::ranges::view<T> is evaluated on GCC 12 / libstdc++ 12:
@@ -518,7 +523,7 @@ struct is_compatible_array_type_impl <
 // filter_view) can match BOTH this iterator-based specialization AND the view-based one
 // below, causing ambiguity. Exclude views here so the two specializations are mutually
 // exclusive: this one handles plain iterable containers, the other handles views.
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
 && !is_compatible_range_view<CompatibleArrayType>::value
 #endif
             >>
@@ -528,7 +533,7 @@ struct is_compatible_array_type_impl <
         range_value_t<CompatibleArrayType>>::value;
 };
 
-#if JSON_HAS_RANGES && !defined(__MINGW32__)
+#if JSON_HAS_RANGE_VIEW_CONVERSION
 template<typename BasicJsonType, typename CompatibleArrayType>
 struct is_compatible_array_type_impl <
     BasicJsonType, CompatibleArrayType,
@@ -604,7 +609,6 @@ struct is_compatible_integer_type_impl <
     std::is_integral<CompatibleNumberIntegerType>::value&&
     !std::is_same<bool, CompatibleNumberIntegerType>::value >>
 {
-    // is there an assert somewhere on overflows?
     using RealLimits = std::numeric_limits<RealIntegerType>;
     using CompatibleLimits = std::numeric_limits<CompatibleNumberIntegerType>;
 
@@ -636,18 +640,6 @@ template<typename BasicJsonType, typename CompatibleType>
 struct is_compatible_type
     : is_compatible_type_impl<BasicJsonType, CompatibleType> {};
 
-// a one-element std::tuple holding a reference to BasicJsonType, as created by
-// std::forward_as_tuple(j); see JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-template<typename BasicJsonType, typename T>
-struct is_basic_json_reference_tuple : std::false_type {};
-
-template<typename BasicJsonType, typename T>
-struct is_basic_json_reference_tuple<BasicJsonType, std::tuple<T>>
-{
-    static constexpr bool value =
-        std::is_reference<T>::value && std::is_same<uncvref_t<T>, BasicJsonType>::value;
-};
-
 template<typename BasicJsonType, typename CompatibleArrayType>
 struct is_compatible_binary_type
 {
@@ -810,20 +802,7 @@ struct has_capacity : std::integral_constant<bool, is_detected<detect_capacity,
 // a naive helper to check if a type is an ordered_map (exploits the fact that
 // ordered_map inherits capacity() from std::vector)
 template <typename T>
-struct is_ordered_map
-{
-    using one = char;
-
-    struct two
-    {
-        char x[2]; // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-    };
-
-    template <typename C> static one test( decltype(&C::capacity) ) ;
-    template <typename C> static two test(...);
-
-    enum { value = sizeof(test<T>(nullptr)) == sizeof(char) }; // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg,cppcoreguidelines-use-enum-class)
-};
+struct is_ordered_map : has_capacity<T> {};
 
 // to avoid useless casts (see https://github.com/nlohmann/json/issues/2893#issuecomment-889152324)
 template < typename T, typename U, enable_if_t < !std::is_same<T, U>::value, int > = 0 >
@@ -847,10 +826,8 @@ using all_signed = conjunction<std::is_signed<Types>...>;
 template<typename... Types>
 using all_unsigned = conjunction<std::is_unsigned<Types>...>;
 
-// there's a disjunction trait in another PR; replace when merged
 template<typename... Types>
-using same_sign = std::integral_constant < bool,
-      all_signed<Types...>::value || all_unsigned<Types...>::value >;
+using same_sign = disjunction<all_signed<Types...>, all_unsigned<Types...>>;
 
 template<typename OfType, typename T>
 using never_out_of_range = std::integral_constant < bool,

include/nlohmann/detail/output/binary_writer.hpp

@@ -116,8 +116,6 @@ class binary_writer
     /*!
     @param[in] j  JSON value to serialize
     @pre       j.type() == value_t::object
-    @throw type_error.316 if a string value or an object key is not valid
-           UTF-8
     */
     void write_bson(const BasicJsonType& j)
     {
@@ -147,8 +145,6 @@ class binary_writer
 
     /*!
     @param[in] j  JSON value to serialize
-    @throw type_error.316 if a string value or an object key is not valid
-           UTF-8
     */
     void write_cbor(const BasicJsonType& j)
     {
@@ -215,8 +211,6 @@ class binary_writer
 
             case value_t::string:
             {
-                check_utf8(*j.m_data.m_value.string, j);
-
                 // step 1: write control byte and the string length
                 write_cbor_head(0x60, j.m_data.m_value.string->size());
 
@@ -286,11 +280,6 @@ class binary_writer
                 // step 2: write each element
                 for (const auto& el : *j.m_data.m_value.object)
                 {
-                    // el.first is checked here, against the object as
-                    // diagnostics context, because write_cbor(el.first)
-                    // converts it to a temporary basic_json that would be
-                    // used as the context instead
-                    check_utf8(el.first, j);
                     write_cbor(el.first);
                     write_cbor(el.second);
                 }
@@ -654,8 +643,6 @@ class binary_writer
     @param[in] add_prefix  whether prefixes need to be used for this value
     @param[in] use_bjdata  whether write in BJData format, default is false
     @param[in] bjdata_version  which BJData version to use, default is draft2
-    @throw type_error.316 if a string value or an object key is not valid
-           UTF-8
     */
     void write_ubjson(const BasicJsonType& j, const bool use_count,
                       const bool use_type, const bool add_prefix = true,
@@ -705,8 +692,6 @@ class binary_writer
 
             case value_t::string:
             {
-                check_utf8(*j.m_data.m_value.string, j);
-
                 if (add_prefix)
                 {
                     oa.write_character(to_char_type('S'));
@@ -869,7 +854,6 @@ class binary_writer
 
                 for (const auto& el : *j.m_data.m_value.object)
                 {
-                    check_utf8(el.first, j);
                     write_number_with_ubjson_prefix(el.first.size(), true, use_bjdata);
                     oa.write_characters(
                           reinterpret_cast<const CharType*>(el.first.data()),
@@ -914,10 +898,6 @@ class binary_writer
     /*!
     @return The size of a BSON document entry header, including the id marker
             and the entry name size (and its null-terminator).
-    @throw out_of_range.409 if @a name contains U+0000, before anything is
-           written
-    @throw type_error.316 if @a name is not valid UTF-8, before anything is
-           written
     */
     static std::size_t calc_bson_entry_header_size(const string_t& name, const BasicJsonType& j)
     {
@@ -927,8 +907,7 @@ class binary_writer
             JSON_THROW(out_of_range::create(409, concat("BSON key cannot contain code point U+0000 (at byte ", std::to_string(it), ")"), &j));
         }
 
-        check_utf8(name, j);
-
+        static_cast<void>(j);
         return /*id*/ 1ul + name.size() + /*zero-terminator*/1u;
     }
 
@@ -984,21 +963,9 @@ class binary_writer
 
     /*!
     @return The size of the BSON-encoded string in @a value
-    @throw type_error.316 if @a value is not valid UTF-8, before anything is
-           written
-
-    @note The UTF-8 check is skipped if @a value is already too long for the
-          32-bit BSON length field (@ref to_bson_length rejects it later, once
-          the size of the whole document is known); this also keeps the check
-          from reading past a StringType that reports a size larger than what
-          it actually holds.
     */
-    static std::size_t calc_bson_string_size(const string_t& value, const BasicJsonType& j)
+    static std::size_t calc_bson_string_size(const string_t& value)
     {
-        if (JSON_HEDLEY_LIKELY(value_in_range_of<std::int32_t>(value.size())))
-        {
-            check_utf8(value, j);
-        }
         return sizeof(std::int32_t) + value.size() + 1ul;
     }
 
@@ -1127,8 +1094,6 @@ class binary_writer
             is neither an object nor an array
     @throw out_of_range.415 if @a j is binary with a subtype that does not fit
            into a byte, before anything is written
-    @throw type_error.316 if @a j is a string that is not valid UTF-8, before
-           anything is written
     */
     static std::size_t calc_bson_value_size(const BasicJsonType& j)
     {
@@ -1150,7 +1115,7 @@ class binary_writer
                 return calc_bson_unsigned_size(j.m_data.m_value.number_unsigned);
 
             case value_t::string:
-                return calc_bson_string_size(*j.m_data.m_value.string, j);
+                return calc_bson_string_size(*j.m_data.m_value.string);
 
             case value_t::null:
                 return 0ul;
@@ -1263,8 +1228,6 @@ class binary_writer
            written
     @throw out_of_range.415 if a binary value's subtype does not fit into a
            byte, before anything is written
-    @throw type_error.316 if a string value or a key is not valid UTF-8,
-           before anything is written
     */
     static std::size_t calc_bson_sizes(const BasicJsonType& document, std::vector<std::size_t>& nested_sizes)
     {
@@ -2289,7 +2252,7 @@ class binary_writer
     */
     void write_bon8_string(const string_t& s, bool& string_open, const BasicJsonType& context)
     {
-        check_utf8(s, context);
+        check_bon8_utf8(s, context);
 
         // a string that follows another string terminates it
         if (string_open)
@@ -2319,7 +2282,7 @@ class binary_writer
     @throw type_error.316 if @a s is not valid UTF-8; the message names the
            first byte of the first invalid or incomplete sequence
     */
-    static void check_utf8(const string_t& s, const BasicJsonType& context)
+    static void check_bon8_utf8(const string_t& s, const BasicJsonType& context)
     {
         static_cast<void>(context); // only used when exceptions are enabled
         const auto* data = reinterpret_cast<const unsigned char*>(s.data());

include/nlohmann/json.hpp

@@ -906,11 +906,11 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     /*!
     @brief how many levels the operation going on in this thread has descended into
 
-    Copying a value, converting one from another specialization, and comparing
-    two values share this count. The library never nests one of them inside
-    another - none of them does either of the other two on the way - and where
-    user code nests them anyway, sharing the count only ends a descent sooner
-    than it had to, which costs a little speed and is never wrong.
+    Copying a value and comparing two values share this count. The library never
+    nests one inside the other - copying a value does not compare one, and
+    comparing two values does not copy them - and where user code nests them
+    anyway, sharing the count only ends a descent sooner than it had to, which
+    costs a little speed and is never wrong.
 
     A byte is enough: the count never exceeds the limit by more than the single
     level that notices the limit has been reached.
@@ -1267,222 +1267,6 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         copy_iteratively(src);
     }
 
-    /*!
-    @brief convert the value @a val of another specialization into this null
-           value; @a val must be neither an object nor an array
-
-    Converting such a value never descends, so both ways of converting an
-    object or an array (@ref convert_structured) leave their elements of this
-    kind to the converting constructor, which leaves them to this.
-    */
-    template<typename BasicJsonType>
-    void convert_leaf(const BasicJsonType& val)
-    {
-        using other_boolean_t = typename BasicJsonType::boolean_t;
-        using other_number_float_t = typename BasicJsonType::number_float_t;
-        using other_number_integer_t = typename BasicJsonType::number_integer_t;
-        using other_number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-        using other_string_t = typename BasicJsonType::string_t;
-        using other_binary_t = typename BasicJsonType::binary_t;
-
-        switch (val.type())
-        {
-            case value_t::boolean:
-                JSONSerializer<other_boolean_t>::to_json(*this, val.template get<other_boolean_t>());
-                break;
-            case value_t::number_float:
-                JSONSerializer<other_number_float_t>::to_json(*this, val.template get<other_number_float_t>());
-                break;
-            case value_t::number_integer:
-                JSONSerializer<other_number_integer_t>::to_json(*this, val.template get<other_number_integer_t>());
-                break;
-            case value_t::number_unsigned:
-                JSONSerializer<other_number_unsigned_t>::to_json(*this, val.template get<other_number_unsigned_t>());
-                break;
-            case value_t::string:
-                JSONSerializer<other_string_t>::to_json(*this, val.template get_ref<const other_string_t&>());
-                break;
-            case value_t::binary:
-                JSONSerializer<other_binary_t>::to_json(*this, val.template get_ref<const other_binary_t&>());
-                break;
-            case value_t::null:
-                // m_data.m_type is already value_t::null
-                break;
-            case value_t::discarded:
-                m_data.m_type = value_t::discarded;
-                break;
-            case value_t::object: // LCOV_EXCL_LINE
-            case value_t::array:  // LCOV_EXCL_LINE
-            default:              // LCOV_EXCL_LINE
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        }
-    }
-
-    /// scratch space for the converted elements of the arrays that
-    /// @ref convert_iteratively has yet to create
-    using convert_scratch_t = std::vector<basic_json, AllocatorType<basic_json>>;
-
-    /*!
-    @brief create the object or array @a val converted into this null value
-
-    Its converted elements are the last `val.size()` entries of @a elements (an
-    array) or of @a members (an object); they are moved into the container in
-    one go and then removed.
-    */
-    template<typename BasicJsonType>
-    void convert_level(const BasicJsonType& val, convert_scratch_t& elements, copy_scratch_t& members)
-    {
-        if (val.is_object())
-        {
-            const auto first = members.end() - static_cast<typename copy_scratch_t::difference_type>(val.size());
-            m_data.m_value.object = create<object_t>(std::make_move_iterator(first),
-                                    std::make_move_iterator(members.end()));
-            // only now that the object exists may this stop being a null value
-            m_data.m_type = value_t::object;
-            members.erase(first, members.end());
-        }
-        else
-        {
-            const auto first = elements.end() - static_cast<typename convert_scratch_t::difference_type>(val.size());
-            m_data.m_value.array = create<array_t>(std::make_move_iterator(first),
-                                                   std::make_move_iterator(elements.end()));
-            // only now that the array exists may this stop being a null value
-            m_data.m_type = value_t::array;
-            elements.erase(first, elements.end());
-        }
-
-        set_parents();
-    }
-
-    /*!
-    @brief convert the object or array @a val of another specialization into
-           this null value without recursing
-
-    The containers whose conversion has begun are kept on an explicit stack
-    rather than on the call stack. Unlike @ref copy_iteratively, this builds
-    every container from the bottom up: all its elements are converted first,
-    and the container is then created from them in one go, the way the range
-    constructor that converts the levels above the bound does. The two object
-    types need not enumerate their members in the same order, so the members
-    could not be paired up by position anyway, and building from a range keeps
-    what the range constructor does with keys that become equal on conversion.
-
-    Every value is complete before it is handed on, and a container gets its
-    type only once it exists, so whatever throws, every value left behind can
-    be destroyed.
-    */
-    template<typename BasicJsonType>
-    void convert_iteratively(const BasicJsonType& val)
-    {
-        using other_const_iterator = typename BasicJsonType::const_iterator;
-
-        // the containers whose conversion has begun, innermost last, each with
-        // its element to convert next
-        std::vector<std::pair<const BasicJsonType*, other_const_iterator>> pending;
-
-        // the converted elements of the pending arrays and the converted
-        // members of the pending objects, those of the innermost one last
-        convert_scratch_t elements;
-        copy_scratch_t members;
-
-        pending.emplace_back(&val, val.cbegin());
-
-        for (;;)
-        {
-            const BasicJsonType& container = *pending.back().first;
-            // a copy, as descending below can reallocate pending; the
-            // iterator kept in pending is only advanced through pending.back()
-            const other_const_iterator next = pending.back().second;
-
-            if (next != container.cend())
-            {
-                if (next->is_structured())
-                {
-                    // convert its elements first; next stays where it is until
-                    // the converted container is handed back to this one
-                    pending.emplace_back(&*next, next->cbegin());
-                    continue;
-                }
-
-                // the converting constructor does not descend into this value
-                if (container.is_object())
-                {
-                    members.emplace_back(next.key(), *next);
-                }
-                else
-                {
-                    elements.emplace_back(*next);
-                }
-                ++pending.back().second;
-                continue;
-            }
-
-            // all elements of the container are converted: create it
-            pending.pop_back();
-
-            if (pending.empty())
-            {
-                convert_level(container, elements, members);
-                return;
-            }
-
-            basic_json converted;
-            converted.convert_level(container, elements, members);
-#if JSON_DIAGNOSTIC_POSITIONS
-            converted.start_position = container.start_pos();
-            converted.end_position = container.end_pos();
-#endif
-
-            // hand it to the container it is an element of
-            if (pending.back().first->is_object())
-            {
-                members.emplace_back(pending.back().second.key(), std::move(converted));
-            }
-            else
-            {
-                elements.push_back(std::move(converted));
-            }
-            ++pending.back().second;
-        }
-    }
-
-    /*!
-    @brief convert the object or array @a val of another specialization into
-           this null value
-
-    Converting a container converts its elements, so a value nested deeply
-    enough used to exhaust the call stack. The descent is bounded here as in
-    @ref copy_structured: the first `detail::recursion_depth_limit()` levels
-    are converted by the containers' range constructors, just as they always were,
-    and anything below that is converted without the call stack by
-    @ref convert_iteratively.
-
-    @sa https://github.com/nlohmann/json/issues/5650
-    */
-    template<typename BasicJsonType>
-    void convert_structured(const BasicJsonType& val)
-    {
-        const nesting_depth_guard guard;
-
-        if (JSON_HEDLEY_LIKELY(guard.okay()))
-        {
-            // every element comes back to the converting constructor
-            if (val.is_object())
-            {
-                using other_object_t = typename BasicJsonType::object_t;
-                JSONSerializer<other_object_t>::to_json(*this, val.template get_ref<const other_object_t&>());
-            }
-            else
-            {
-                using other_array_t = typename BasicJsonType::array_t;
-                JSONSerializer<other_array_t>::to_json(*this, val.template get_ref<const other_array_t&>());
-            }
-            return;
-        }
-
-        convert_iteratively(val);
-    }
-
 
     /// the result of comparing two values, including values that cannot be
     /// ordered at all, such as a discarded value or a NaN
@@ -1812,12 +1596,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     template < typename CompatibleType,
                typename U = detail::uncvref_t<CompatibleType>,
                detail::enable_if_t <
-                   !detail::is_basic_json<U>::value && detail::is_compatible_type<basic_json_t, U>::value
-#if JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-                   // see https://github.com/nlohmann/json/issues/2226
-                   && !detail::is_basic_json_reference_tuple<basic_json_t, U>::value
-#endif
-                   , int > = 0 >
+                   !detail::is_basic_json<U>::value && detail::is_compatible_type<basic_json_t, U>::value, int > = 0 >
     basic_json(CompatibleType && val) noexcept(noexcept( // NOLINT(bugprone-forwarding-reference-overload,bugprone-exception-escape)
                 JSONSerializer<U>::to_json(std::declval<basic_json_t&>(),
                                            std::forward<CompatibleType>(val))))
@@ -1838,13 +1617,49 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
           end_position(val.end_pos())
 #endif
     {
-        if (val.is_structured())
+        using other_boolean_t = typename BasicJsonType::boolean_t;
+        using other_number_float_t = typename BasicJsonType::number_float_t;
+        using other_number_integer_t = typename BasicJsonType::number_integer_t;
+        using other_number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+        using other_string_t = typename BasicJsonType::string_t;
+        using other_object_t = typename BasicJsonType::object_t;
+        using other_array_t = typename BasicJsonType::array_t;
+        using other_binary_t = typename BasicJsonType::binary_t;
+
+        switch (val.type())
         {
-            convert_structured(val);
-        }
-        else
-        {
-            convert_leaf(val);
+            case value_t::boolean:
+                JSONSerializer<other_boolean_t>::to_json(*this, val.template get<other_boolean_t>());
+                break;
+            case value_t::number_float:
+                JSONSerializer<other_number_float_t>::to_json(*this, val.template get<other_number_float_t>());
+                break;
+            case value_t::number_integer:
+                JSONSerializer<other_number_integer_t>::to_json(*this, val.template get<other_number_integer_t>());
+                break;
+            case value_t::number_unsigned:
+                JSONSerializer<other_number_unsigned_t>::to_json(*this, val.template get<other_number_unsigned_t>());
+                break;
+            case value_t::string:
+                JSONSerializer<other_string_t>::to_json(*this, val.template get_ref<const other_string_t&>());
+                break;
+            case value_t::object:
+                JSONSerializer<other_object_t>::to_json(*this, val.template get_ref<const other_object_t&>());
+                break;
+            case value_t::array:
+                JSONSerializer<other_array_t>::to_json(*this, val.template get_ref<const other_array_t&>());
+                break;
+            case value_t::binary:
+                JSONSerializer<other_binary_t>::to_json(*this, val.template get_ref<const other_binary_t&>());
+                break;
+            case value_t::null:
+                *this = nullptr;
+                break;
+            case value_t::discarded:
+                m_data.m_type = value_t::discarded;
+                break;
+            default:            // LCOV_EXCL_LINE
+                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
         }
         JSON_ASSERT(m_data.m_type == val.type());
 

tests/src/unit-allocator.cpp

@@ -479,77 +479,6 @@ TEST_CASE("deep copy uses the provided allocator")
     CHECK(copy == j);
 }
 
-namespace
-{
-// the number of constructions countdown_allocator lets happen, including the
-// one that fails; 0 means none ever fails
-std::size_t constructions_until_failure = 0;
-
-template<class T>
-struct countdown_allocator : std::allocator<T>
-{
-    using std::allocator<T>::allocator;
-
-    template<class U, class... Args>
-    void construct(U* p, Args&& ... args)
-    {
-        if (constructions_until_failure != 0 && --constructions_until_failure == 0)
-        {
-            throw std::bad_alloc();
-        }
-
-        ::new (static_cast<void*>(p)) U(std::forward<Args>(args)...);
-    }
-
-    template <class U>
-    struct rebind
-    {
-        using other = countdown_allocator<U>;
-    };
-};
-} // namespace
-
-TEST_CASE("converting a deeply nested value from another specialization fails cleanly (#5650)")
-{
-    using countdown_json = nlohmann::basic_json<std::map,
-          std::vector,
-          std::string,
-          bool,
-          std::int64_t,
-          std::uint64_t,
-          double,
-          countdown_allocator>;
-
-    // deeper than the 128 levels the converting constructor descends into, so
-    // that failures land on both sides of the bound - or, built with
-    // JSON_NO_THREAD_LOCAL, all in the iterative conversion
-    json j = {1, "two", {{"three", 3}}};
-    for (std::size_t i = 0; i < 150; ++i)
-    {
-        j = json{{"a", json::array({j, "sibling"})}};
-    }
-
-    // Fail every construction in turn. Each failure has to reach the caller,
-    // and everything built until then has to be destroyed cleanly.
-    std::size_t failures = 0;
-    for (std::size_t n = 1;; ++n)
-    {
-        constructions_until_failure = n;
-        try
-        {
-            const countdown_json converted = j;
-            constructions_until_failure = 0;
-            CHECK(converted.dump() == j.dump());
-            break;
-        }
-        catch (const std::bad_alloc&)
-        {
-            ++failures;
-        }
-    }
-    CHECK(failures > 0);
-}
-
 namespace
 {
 template<class T>

tests/src/unit-bjdata.cpp

@@ -4025,30 +4025,6 @@ TEST_CASE("Universal Binary JSON Specification Examples 1")
             CHECK(json::to_bjdata(j) == v);
             CHECK(json::from_bjdata(v) == j);
         }
-
-        SECTION("ill-formed UTF-8 (see #5651)")
-        {
-            // a string value whose bytes are not valid UTF-8 (0xC0 0xAE is an
-            // overlong encoding of '.') is rejected at decode time, matching
-            // every other kind of malformed binary input, and to_bjdata()
-            // rejects it as well, so a value it accepts can always be read
-            // back
-            const std::vector<uint8_t> v = {'S', 'i', 2, 0xc0, 0xae};
-            json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_bjdata(v), "[json.exception.parse_error.113] parse error at byte 5: syntax error while parsing BJData string: invalid string: ill-formed UTF-8 byte", json::parse_error&);
-            CHECK(json::from_bjdata(v, true, false).is_discarded());
-
-            CHECK_THROWS_WITH_AS(json::to_bjdata(json("\xFF")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-            // a truncated multi-byte sequence
-            CHECK_THROWS_WITH_AS(json::to_bjdata(json("\xC3")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC3", json::type_error&);
-            // an encoded surrogate half (U+D800)
-            CHECK_THROWS_WITH_AS(json::to_bjdata(json("\xED\xA0\x80")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xED", json::type_error&);
-            // an overlong encoding of '.'
-            CHECK_THROWS_WITH_AS(json::to_bjdata(json("\xC0\xAF")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC0", json::type_error&);
-
-            // an object key with ill-formed UTF-8 is rejected the same way
-            CHECK_THROWS_WITH_AS(json::to_bjdata(json{{"\xFF", 1}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-        }
     }
 
     SECTION("Array Type")

tests/src/unit-bson.cpp

@@ -151,44 +151,6 @@ TEST_CASE("BSON")
 #endif
     }
 
-    SECTION("ill-formed UTF-8 (see #5651)")
-    {
-        // a BSON document {"s": "\xC0\xAE"} (0xC0 0xAE is an overlong
-        // encoding of '.'); the reader rejects an ill-formed string value at
-        // decode time
-        const std::vector<uint8_t> v =
-        {
-            0x0F, 0x00, 0x00, 0x00, // document length
-            0x02, 's', 0x00,        // type 0x02 (string), key "s"
-            0x03, 0x00, 0x00, 0x00, // string length (including null)
-            0xc0, 0xae, 0x00,       // string content and its null terminator
-            0x00                    // document terminator
-        };
-        json _;
-        CHECK_THROWS_WITH_AS(_ = json::from_bson(v), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing BSON string: invalid string: ill-formed UTF-8 byte", json::parse_error&);
-        CHECK(json::from_bson(v, true, false).is_discarded());
-
-        // to_bson() rejects the same kind of ill-formed string value, before
-        // any bytes reach the output adapter (the BSON document length
-        // prefix must be known up front, so nothing is written incrementally)
-        std::vector<std::uint8_t> out{0x42}; // a sentinel byte the writer must not touch
-        CHECK_THROWS_WITH_AS(json::to_bson(json{{"s", "\xFF"}}, nlohmann::detail::output_adapter<std::uint8_t>(out)), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-        CHECK(out == std::vector<std::uint8_t> {0x42});
-
-        CHECK_THROWS_WITH_AS(json::to_bson(json{{"s", "\xFF"}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-        // a truncated multi-byte sequence
-        CHECK_THROWS_WITH_AS(json::to_bson(json{{"s", "\xC3"}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC3", json::type_error&);
-        // an encoded surrogate half (U+D800)
-        CHECK_THROWS_WITH_AS(json::to_bson(json{{"s", "\xED\xA0\x80"}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xED", json::type_error&);
-        // an overlong encoding of '.'
-        CHECK_THROWS_WITH_AS(json::to_bson(json{{"s", "\xC0\xAF"}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC0", json::type_error&);
-
-        // an object key with ill-formed UTF-8 is rejected as well; unlike
-        // the reader (which never validates element names), the writer
-        // checks both string values and object keys
-        CHECK_THROWS_WITH_AS(json::to_bson(json{{"\xFF", 1}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-    }
-
     SECTION("lengths exceeding INT32_MAX cannot be serialized to BSON")
     {
         // out_of_range.412 is thrown from a single shared helper

tests/src/unit-cbor.cpp

@@ -1896,25 +1896,6 @@ TEST_CASE("CBOR")
             CHECK(json::from_cbor(json::to_cbor(j)) == j);
         }
 
-        SECTION("to_cbor rejects ill-formed UTF-8 (see #5651)")
-        {
-            // to_cbor() must reject the same ill-formed strings from_cbor()
-            // rejects, so a value it accepts can always be read back
-            CHECK_THROWS_WITH_AS(json::to_cbor(json("\xFF")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-            // a truncated multi-byte sequence
-            CHECK_THROWS_WITH_AS(json::to_cbor(json("\xC3")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC3", json::type_error&);
-            // an encoded surrogate half (U+D800)
-            CHECK_THROWS_WITH_AS(json::to_cbor(json("\xED\xA0\x80")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xED", json::type_error&);
-            // an overlong encoding of '.'
-            CHECK_THROWS_WITH_AS(json::to_cbor(json("\xC0\xAF")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC0", json::type_error&);
-
-            // an object key with ill-formed UTF-8 is rejected the same way
-            CHECK_THROWS_WITH_AS(json::to_cbor(json{{"\xFF", 1}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-
-            // binary values are not text and are unaffected
-            CHECK_NOTHROW(json::to_cbor(json::binary(std::vector<std::uint8_t>({0xFF}))));
-        }
-
         SECTION("invalid UTF-8 in indefinite-length string")
         {
             json _;

tests/src/unit-conversions.cpp

@@ -430,6 +430,37 @@ TEST_CASE("value conversion")
             CHECK(std::equal(std::begin(nbs[0][0][0]), std::end(nbs[1][1][1]), std::begin(nbs2[0][0][0])));
         }
 
+        SECTION("built-in arrays: 5D")
+        {
+            // NOLINTBEGIN(misc-const-correctness,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
+            const int nbs[1][1][1][2][2] = {{{{{0, 1}, {2, 3}}}}};
+            int nbs2[1][1][1][2][2] = {{{{{0, 0}, {0, 0}}}}};
+            // NOLINTEND(misc-const-correctness,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
+
+            const json j2 = nbs;
+            j2.get_to(nbs2);
+            CHECK(std::equal(std::begin(nbs[0][0][0][0]), std::end(nbs[0][0][0][1]), std::begin(nbs2[0][0][0][0])));
+        }
+
+        SECTION("built-in arrays: mismatched shape")
+        {
+            // NOLINTBEGIN(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
+            int nbs2[2][3] = {{0, 0, 0}, {0, 0, 0}};
+            // NOLINTEND(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
+
+            SECTION("not an array")
+            {
+                const json j2 = 42;
+                CHECK_THROWS_WITH_AS(j2.get_to(nbs2), "[json.exception.type_error.304] cannot use at() with number", json::type_error&);
+            }
+
+            SECTION("too few elements")
+            {
+                const json j2 = {{0, 1, 2}};
+                CHECK_THROWS_WITH_AS(j2.get_to(nbs2), "[json.exception.out_of_range.401] array index 1 is out of range", json::out_of_range&);
+            }
+        }
+
         SECTION("std::deque<json>")
         {
             std::deque<json> a{"previous", "value"};
@@ -1726,6 +1757,34 @@ NLOHMANN_JSON_SERIALIZE_ENUM_STRICT(StrictTaskState,
     {STRICT_TS_COMPLETED, "completed"},
 })
 
+// regression test for #5708 item 2: NLOHMANN_JSON_SERIALIZE_ENUM_STRICT must not rely on
+// unqualified lookup of a helper name that a user's own namespace may also declare
+namespace ns_with_colliding_name
+{
+// NOLINTNEXTLINE(misc-use-internal-linkage) - used to shadow the library's internal helper name
+inline void templated_json_throw(int /*unused*/) {}
+
+enum class colliding_enum { a, b };
+
+// NOLINTNEXTLINE(misc-use-internal-linkage,misc-const-correctness,cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays) - false positive
+NLOHMANN_JSON_SERIALIZE_ENUM_STRICT(colliding_enum,
+{
+    {colliding_enum::a, "a"},
+    {colliding_enum::b, "b"}
+})
+} // namespace ns_with_colliding_name
+
+TEST_CASE("NLOHMANN_JSON_SERIALIZE_ENUM_STRICT in a namespace with a colliding name")
+{
+    using ns_with_colliding_name::colliding_enum;
+
+    CHECK(json(colliding_enum::a) == "a");
+    CHECK(colliding_enum::b == json("b"));
+
+    json _;
+    CHECK_THROWS_WITH_AS(_ = json("nope").get<colliding_enum>(), "[json.exception.out_of_range.410] enum value out of range for colliding_enum: \"nope\"", json::out_of_range&);
+}
+
 TEST_CASE("Strict JSON to enum mapping")
 {
     SECTION("enum class")

tests/src/unit-diagnostic-positions.cpp

@@ -141,58 +141,6 @@ TEST_CASE("Better diagnostics with positions")
         check_objects(300);
     }
 
-    SECTION("converting keeps the positions of nested values (#5650)")
-    {
-        // Values nested deeper than the converting constructor's descent bound
-        // are converted without the call stack, on a path that has to carry the
-        // positions of every value over itself. Objects and arrays take turns,
-        // and the innermost value is null, which used to lose its positions.
-        const auto check_conversion = [](std::size_t depth)
-        {
-            CAPTURE(depth)
-
-            std::string text;
-            std::string closing;
-            for (std::size_t i = 0; i < depth; ++i)
-            {
-                text += (i % 2 == 0) ? "[12, " : R"({"b":1, "a":)";
-                closing += (i % 2 == 0) ? ']' : '}';
-            }
-            text += "null";
-            text.append(closing.rbegin(), closing.rend());
-
-            const json original = json::parse(text);
-            const nlohmann::ordered_json converted = original;
-
-            const json* o = &original;
-            const nlohmann::ordered_json* c = &converted;
-            for (std::size_t level = 0; level <= depth; ++level)
-            {
-                CAPTURE(level)
-                REQUIRE(c->start_pos() == o->start_pos());
-                REQUIRE(c->end_pos() == o->end_pos());
-
-                if (level < depth)
-                {
-                    // the number beside the value nested next
-                    const json& o_number = o->is_object() ? o->at("b") : o->at(0);
-                    const nlohmann::ordered_json& c_number = c->is_object() ? c->at("b") : c->at(0);
-                    REQUIRE(c_number.start_pos() == o_number.start_pos());
-                    REQUIRE(c_number.end_pos() == o_number.end_pos());
-
-                    o = o->is_object() ? &o->at("a") : &o->at(1);
-                    c = c->is_object() ? &c->at("a") : &c->at(1);
-                }
-            }
-        };
-
-        check_conversion(1);
-        check_conversion(127);
-        check_conversion(128);
-        check_conversion(129);
-        check_conversion(300);
-    }
-
     SECTION("JSON patch add to primitive parent (#4292)")
     {
         // the JSON Patch "add" target /foo/bar/baz has a string parent

tests/src/unit-diagnostics.cpp

@@ -341,36 +341,6 @@ TEST_CASE("Regression tests for extended diagnostics")
         }
     }
 
-    SECTION("Regression test for issue #5650 - converting keeps the parents of nested values")
-    {
-        // A value nested deeper than the converting constructor's descent bound
-        // is converted without the call stack. Every container that path creates
-        // has to have the parents of its children set, or the JSON Pointer in the
-        // diagnostic is cut short. Objects and arrays take turns.
-        const std::size_t pairs = 150;
-
-        json j = "not a number";
-        std::string pointer;
-        for (std::size_t i = 0; i < pairs; ++i)
-        {
-            j = json{{"a", json::array({j})}};
-            pointer += "/a/0";
-        }
-
-        const nlohmann::ordered_json converted = j;
-
-        const nlohmann::ordered_json* inner = &converted;
-        for (std::size_t i = 0; i < pairs; ++i)
-        {
-            inner = &inner->at("a").at(0);
-        }
-
-        std::string const expected = "[json.exception.type_error.302] (" + pointer + ") type must be number, but is string";
-        int i = 0;
-        CHECK_THROWS_WITH_AS(i = inner->get<int>(), expected.c_str(), nlohmann::ordered_json::type_error);
-        CHECK(i == 0);
-    }
-
     SECTION("Regression test for issue #5668 - wrong path for std::map/unordered_map with non-string keys")
     {
         // a map with non-string keys is read from an array of [key, value] arrays;

tests/src/unit-disable-tuple-reference-conversion.cpp

@@ -1,93 +0,0 @@
-//     __ _____ _____ _____
-//  __|  |   __|     |   | |  JSON for Modern C++ (supporting code)
-// |  |  |__   |  |  | | | |  version 3.12.0
-// |_____|_____|_____|_|___|  https://github.com/nlohmann/json
-//
-// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
-// SPDX-License-Identifier: MIT
-
-#include "doctest_compatibility.h"
-
-// This file tests the opt-in JSON_DISABLE_TUPLE_REFERENCE_CONVERSION, so it
-// defines the macro itself rather than relying on a -D flag, and runs in every
-// build.
-#ifdef JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-    #undef JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-#endif
-
-#define JSON_DISABLE_TUPLE_REFERENCE_CONVERSION 1
-
-#include <nlohmann/json.hpp>
-using nlohmann::json;
-using nlohmann::ordered_json;
-
-#include <string>
-#include <tuple>
-#include <type_traits>
-#include <utility>
-
-// clang before 4 and GCC before 5 cannot create a std::tuple of basic_json
-// references at all, with or without JSON_DISABLE_TUPLE_REFERENCE_CONVERSION:
-// the tuple constructors make them instantiate basic_json's conversion operator
-// for libstdc++'s internal tuple bases, which fails hard
-#if (defined(__clang__) && __clang_major__ < 4) || (!defined(__clang__) && defined(__GNUC__) && __GNUC__ < 5)
-    #define SKIP_TESTS_FOR_JSON_REFERENCE_TUPLES
-#endif
-
-TEST_CASE("JSON_DISABLE_TUPLE_REFERENCE_CONVERSION")
-{
-    SECTION("json is not constructible from a one-element tuple of a json reference")
-    {
-        CHECK_FALSE(std::is_constructible<json, std::tuple<json&>>::value);
-        CHECK_FALSE(std::is_constructible<json, std::tuple<const json&>>::value);
-        CHECK_FALSE(std::is_constructible < json, std::tuple < json && >>::value);
-        CHECK_FALSE(std::is_constructible<json, const std::tuple<json&>&>::value);
-        CHECK_FALSE(std::is_constructible<ordered_json, std::tuple<ordered_json&>>::value);
-    }
-
-#ifndef SKIP_TESTS_FOR_JSON_REFERENCE_TUPLES
-    SECTION("issue #2226 - tuple<const json&> from tuple<json&> keeps the reference")
-    {
-        json j = true;
-        const std::tuple<const json&> tup(std::forward_as_tuple(j));
-        CHECK(&std::get<0>(tup) == &j);
-    }
-
-    SECTION("tuple<json> from tuple<json&> copies the element")
-    {
-        const json j = {{"key", "value"}};
-        const std::tuple<json> t1(std::forward_as_tuple(j));
-        CHECK(std::get<0>(t1) == j);
-
-        json j2 = "text";
-        const std::tuple<json> t2(std::forward_as_tuple(std::move(j2)));
-        CHECK(std::get<0>(t2) == "text");
-    }
-#endif
-
-    SECTION("other tuple conversions are not affected")
-    {
-        const json j = true;
-
-        // one-element tuple holding a json value
-        CHECK(json(std::make_tuple(j)) == json::array({true}));
-
-        // tuples with more than one element, even when holding references
-        int i = 1;
-#ifndef SKIP_TESTS_FOR_JSON_REFERENCE_TUPLES
-        CHECK(json(std::forward_as_tuple(i, j)) == json::array({1, true}));
-        CHECK(json(std::forward_as_tuple(j, j)) == json::array({true, true}));
-#endif
-
-        // one-element tuples holding references to other types
-        std::string s = "text";
-        CHECK(json(std::forward_as_tuple(s)) == json::array({"text"}));
-        CHECK(json(std::forward_as_tuple(i)) == json::array({1}));
-
-#ifndef SKIP_TESTS_FOR_JSON_REFERENCE_TUPLES
-        // a reference to a different basic_json specialization
-        ordered_json oj = true;
-        CHECK(json(std::forward_as_tuple(oj)) == json::array({true}));
-#endif
-    }
-}

tests/src/unit-element_access2.cpp

@@ -516,6 +516,16 @@ TEST_CASE_TEMPLATE("element access 2", Json, nlohmann::json, nlohmann::ordered_j
                     CHECK(j_array.value("/-"_json_pointer, 42) == 42);
                     CHECK(j_array_const.value("/-"_json_pointer, 42) == 42);
 
+                    // Test an index that is syntactically valid but exceeds size_type, and one
+                    // with a trailing non-digit: both must yield the default value rather than
+                    // throw, even with exceptions disabled (regression test for #5708 item 4 /
+                    // #5672: get_checked_or_null() no longer relies on a JSON_TRY/
+                    // JSON_INTERNAL_CATCH around array_index() to turn these into "not found")
+                    CHECK(j_array.value("/18446744073709551615"_json_pointer, 42) == 42);
+                    CHECK(j_array_const.value("/18446744073709551615"_json_pointer, 42) == 42);
+                    CHECK(j_array.value("/1a"_json_pointer, 42) == 42);
+                    CHECK(j_array_const.value("/1a"_json_pointer, 42) == 42);
+
 #if !defined(JSON_NOEXCEPTION)
                     // Test malformed index (non-numeric) throws parse_error
                     CHECK_THROWS_WITH_AS(j_array.value("/foo"_json_pointer, 1), "[json.exception.parse_error.109] parse error: array index 'foo' is not a number", typename Json::parse_error&);

tests/src/unit-large_json.cpp

@@ -13,7 +13,6 @@ using nlohmann::json;
 
 #include <algorithm>
 #include <string>
-#include <vector>
 
 TEST_CASE("tests on very large JSONs")
 {
@@ -54,24 +53,6 @@ const json* innermost_value(const json& j, std::size_t& depth)
     return current;
 }
 
-// The text of a value nested depth levels deep around the number 0. Level i is
-// an array if pattern[i % pattern.size()] is '[', and otherwise an object with
-// the single member "a", which every object type enumerates in the same order.
-std::string nested_text(std::size_t depth, const std::string& pattern)
-{
-    std::string text;
-    std::string closing;
-    for (std::size_t i = 0; i < depth; ++i)
-    {
-        const bool array = pattern[i % pattern.size()] == '[';
-        text += array ? "[" : "{\"a\":";
-        closing += array ? ']' : '}';
-    }
-    text += '0';
-    text.append(closing.rbegin(), closing.rend());
-    return text;
-}
-
 } // namespace
 
 TEST_CASE("tests on deeply nested JSONs")
@@ -243,114 +224,5 @@ TEST_CASE("tests on deeply nested JSONs")
             CHECK(*innermost_value(j, unused) == 0);
         }
     }
-
-    SECTION("issue #5650 - stack overflow converting between specializations")
-    {
-        const std::vector<std::string> patterns = {"[", "{", "[{"};
-
-        SECTION("json to ordered_json")
-        {
-            for (const auto& pattern : patterns)
-            {
-                CAPTURE(pattern);
-                const std::string text = nested_text(depth, pattern);
-                const json j = json::parse(text);
-
-                const nlohmann::ordered_json converted = j;
-                CHECK(converted.dump() == text);
-            }
-        }
-
-        SECTION("ordered_json to json")
-        {
-            for (const auto& pattern : patterns)
-            {
-                CAPTURE(pattern);
-                const std::string text = nested_text(depth, pattern);
-                const nlohmann::ordered_json o = nlohmann::ordered_json::parse(text);
-
-                const json converted = o;
-                CHECK(converted.dump() == text);
-            }
-        }
-
-        SECTION("get<ordered_json>()")
-        {
-            for (const auto& pattern : patterns)
-            {
-                CAPTURE(pattern);
-                const std::string text = nested_text(depth, pattern);
-                const json j = json::parse(text);
-
-                CHECK(j.get<nlohmann::ordered_json>().dump() == text);
-            }
-        }
-
-        SECTION("depths around the bound of the recursive descent")
-        {
-            for (std::size_t d = 1; d <= 300; ++d)
-            {
-                CAPTURE(d);
-                for (const auto& pattern : patterns)
-                {
-                    CAPTURE(pattern);
-                    const std::string text = nested_text(d, pattern);
-                    const json j = json::parse(text);
-
-                    const nlohmann::ordered_json converted = j;
-                    CHECK(converted.dump() == text);
-                    const json back = converted;
-                    CHECK(back.dump() == text);
-                }
-            }
-        }
-
-        SECTION("values below the bound are converted as values above it")
-        {
-            // Bury a value below the bound, where it is converted without the
-            // call stack, and compare it with the same value converted on its
-            // own by the containers' range constructors. Its objects have
-            // members that the two object types enumerate in different orders.
-            const auto bury = [](nlohmann::ordered_json value)
-            {
-                for (std::size_t i = 0; i < 200; ++i)
-                {
-                    value = nlohmann::ordered_json::array({std::move(value)});
-                }
-                return value;
-            };
-            const auto dig = [](const json & value)
-            {
-                const json* current = &value;
-                for (std::size_t i = 0; i < 200; ++i)
-                {
-                    current = &current->at(0);
-                }
-                return current;
-            };
-
-            nlohmann::ordered_json value = nlohmann::ordered_json::object();
-            value["z"] = {1, -2, 3U, 4.5, true, nullptr, "six", nlohmann::ordered_json::binary({7, 8}, 9),
-                          nlohmann::ordered_json::binary({10}), nlohmann::ordered_json::array(), nlohmann::ordered_json::object()
-                         };
-            value["y"] = {{"x", {{"w", 1}, {"v", 2}}}, {"u", {3, {{"t", 4}, {"s", 5}}}}};
-            value["r"] = nlohmann::ordered_json::array({nlohmann::ordered_json(nlohmann::ordered_json::value_t::discarded)});
-
-            const json converted_above = value;
-            const json buried = bury(value);
-            const json& converted_below = *dig(buried);
-
-            CHECK(converted_below.dump() == converted_above.dump());
-            CHECK(converted_below.at("z").at(7).get_binary().subtype() == 9);
-            CHECK_FALSE(converted_below.at("z").at(8).get_binary().has_subtype());
-            CHECK(converted_below.at("r").at(0).is_discarded());
-
-            // a discarded value is never equal to anything, so compare the rest
-            value.erase("r");
-            const json without_discarded_above = value;
-            const json without_discarded_buried = bury(value);
-            CHECK(*dig(without_discarded_buried) == without_discarded_above);
-        }
-    }
 }
 

tests/src/unit-msgpack.cpp

@@ -1614,39 +1614,19 @@ TEST_CASE("MessagePack")
             CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81})), "[json.exception.parse_error.110] parse error at byte 2: syntax error while parsing MessagePack string: unexpected end of input", json::parse_error&);
         }
 
-        SECTION("ill-formed UTF-8 in string (see #5529, #5651)")
+        SECTION("invalid UTF-8 in string (see #5529)")
         {
-            // the MessagePack specification explicitly allows a str object to
-            // contain a byte sequence that is not valid UTF-8 and expects a
-            // deserializer to hand the original bytes back unchanged; this
-            // library follows that, unlike CBOR/UBJSON/BJData/BSON, whose
-            // specifications require text strings to be valid UTF-8
-
             // a fixstr of length 2 (0xA0 | 2) whose bytes are not valid UTF-8
-            // (0xC0 0xAE is an overlong encoding of '.') round-trips byte for
-            // byte as a string value
-            const std::vector<uint8_t> ill_formed_value = {0xa2, 0xc0, 0xae};
-            json j_value;
-            CHECK_NOTHROW(j_value = json::from_msgpack(ill_formed_value));
-            REQUIRE(j_value.is_string());
-            CHECK(j_value.get_ref<const json::string_t&>() == std::string("\xc0\xae"));
-            CHECK(json::from_msgpack(json::to_msgpack(j_value)) == j_value);
-            // dump() still requires valid UTF-8 and throws for such a value,
-            // unless an error handler that replaces or ignores the bytes is
-            // passed
-            CHECK_THROWS_AS(j_value.dump(), json::type_error&);
-
-            // the same bytes as an object key round-trip as well
-            const std::vector<uint8_t> ill_formed_key = {0x81, 0xa2, 0xc0, 0xae, 0x01};
-            json j_key;
-            CHECK_NOTHROW(j_key = json::from_msgpack(ill_formed_key));
-            REQUIRE(j_key.is_object());
-            CHECK(j_key.contains(std::string("\xc0\xae")));
-            CHECK(json::from_msgpack(json::to_msgpack(j_key)) == j_key);
+            // (0xC0 0xAE is an overlong encoding of '.') must be rejected at
+            // decode time, matching every other kind of malformed binary
+            // input, rather than only failing later when the resulting
+            // value is dumped
+            json _;
+            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0xa2, 0xc0, 0xae})), "[json.exception.parse_error.113] parse error at byte 3: syntax error while parsing MessagePack string: invalid string: ill-formed UTF-8 byte", json::parse_error&);
+            CHECK(json::from_msgpack(std::vector<uint8_t>({0xa2, 0xc0, 0xae}), true, false).is_discarded());
 
             // a MessagePack bin8 blob with the very same bytes is NOT text
             // and must still be accepted as-is
-            json _;
             CHECK_NOTHROW(_ = json::from_msgpack(std::vector<uint8_t>({0xc4, 0x02, 0xc0, 0xae})));
             CHECK(_ == json::binary(std::vector<std::uint8_t>({0xc0, 0xae})));
 

tests/src/unit-regression2.cpp

@@ -18,19 +18,6 @@
 // for some reason including this after the json header leads to linker errors with VS 2017...
 #include <locale>
 
-// skip tests if JSON_DISABLE_TUPLE_REFERENCE_CONVERSION=1 (#2226)
-#if defined(JSON_DISABLE_TUPLE_REFERENCE_CONVERSION) && (JSON_DISABLE_TUPLE_REFERENCE_CONVERSION == 1)
-    #define SKIP_TESTS_FOR_TUPLE_REFERENCE_CONVERSION
-#endif
-
-// clang before 4 and GCC before 5 cannot create a std::tuple of basic_json
-// references at all, with or without JSON_DISABLE_TUPLE_REFERENCE_CONVERSION:
-// the tuple constructors make them instantiate basic_json's conversion operator
-// for libstdc++'s internal tuple bases, which fails hard
-#if (defined(__clang__) && __clang_major__ < 4) || (!defined(__clang__) && defined(__GNUC__) && __GNUC__ < 5)
-    #define SKIP_TESTS_FOR_JSON_REFERENCE_TUPLES
-#endif
-
 #define JSON_TESTS_PRIVATE
 #include <nlohmann/json.hpp>
 using json = nlohmann::json;
@@ -41,7 +28,6 @@ using ordered_json = nlohmann::ordered_json;
 
 #include <cstdio>
 #include <list>
-#include <tuple>
 #include <type_traits>
 #include <utility>
 
@@ -556,20 +542,6 @@ TEST_CASE("regression tests 2")
                       )));
     }
 
-#ifndef SKIP_TESTS_FOR_TUPLE_REFERENCE_CONVERSION
-    SECTION("issue #2226 - std::tuple dangling reference - implicit conversion")
-    {
-        // by default, a one-element tuple holding a json reference converts to
-        // a one-element array; JSON_DISABLE_TUPLE_REFERENCE_CONVERSION removes
-        // this conversion (see unit-disable-tuple-reference-conversion.cpp)
-        const json j = true;
-        CHECK(std::is_constructible<json, std::tuple<const json&>>::value);
-#ifndef SKIP_TESTS_FOR_JSON_REFERENCE_TUPLES
-        CHECK(json(std::forward_as_tuple(j)) == json::array({true}));
-#endif
-    }
-#endif
-
     SECTION("PR #2181 - regression bug with lvalue")
     {
         // see https://github.com/nlohmann/json/pull/2181#issuecomment-653326060

tests/src/unit-type_traits.cpp

@@ -10,10 +10,14 @@
 
 #if JSON_TEST_USING_MULTIPLE_HEADERS
     #include <nlohmann/detail/meta/type_traits.hpp>
+    #include <nlohmann/ordered_map.hpp>
 #else
     #include <nlohmann/json.hpp>
 #endif
 
+#include <map>
+#include <string>
+
 TEST_CASE("type traits")
 {
     SECTION("is_c_string")
@@ -83,4 +87,12 @@ TEST_CASE("type traits")
             }
         }
     }
+
+    SECTION("is_ordered_map")
+    {
+        using nlohmann::detail::is_ordered_map;
+
+        CHECK(is_ordered_map<nlohmann::ordered_map<std::string, int>>::value);
+        CHECK_FALSE(is_ordered_map<std::map<std::string, int>>::value);
+    }
 }

tests/src/unit-ubjson.cpp

@@ -2580,30 +2580,6 @@ TEST_CASE("Universal Binary JSON Specification Examples 1")
             CHECK(json::to_ubjson(j) == v);
             CHECK(json::from_ubjson(v) == j);
         }
-
-        SECTION("ill-formed UTF-8 (see #5651)")
-        {
-            // a string value whose bytes are not valid UTF-8 (0xC0 0xAE is an
-            // overlong encoding of '.') is rejected at decode time, matching
-            // every other kind of malformed binary input, and to_ubjson()
-            // rejects it as well, so a value it accepts can always be read
-            // back
-            const std::vector<uint8_t> v = {'S', 'i', 2, 0xc0, 0xae};
-            json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_ubjson(v), "[json.exception.parse_error.113] parse error at byte 5: syntax error while parsing UBJSON string: invalid string: ill-formed UTF-8 byte", json::parse_error&);
-            CHECK(json::from_ubjson(v, true, false).is_discarded());
-
-            CHECK_THROWS_WITH_AS(json::to_ubjson(json("\xFF")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-            // a truncated multi-byte sequence
-            CHECK_THROWS_WITH_AS(json::to_ubjson(json("\xC3")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC3", json::type_error&);
-            // an encoded surrogate half (U+D800)
-            CHECK_THROWS_WITH_AS(json::to_ubjson(json("\xED\xA0\x80")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xED", json::type_error&);
-            // an overlong encoding of '.'
-            CHECK_THROWS_WITH_AS(json::to_ubjson(json("\xC0\xAF")), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xC0", json::type_error&);
-
-            // an object key with ill-formed UTF-8 is rejected the same way
-            CHECK_THROWS_WITH_AS(json::to_ubjson(json{{"\xFF", 1}}), "[json.exception.type_error.316] invalid UTF-8 byte at index 0: 0xFF", json::type_error&);
-        }
     }
 
     SECTION("Array Type")