Copy the text of float tokens only when a SAX handler asks for it

After the digits are converted while scanning, copying the token text into
token_buffer (an out-of-line std::string::append) was about 10% of parsing
canada.json. The only reader is the string argument of
json_sax::number_float(), and the library's own handlers
(json_sax_dom_parser, json_sax_dom_callback_parser, json_sax_acceptor)
ignore it.

For contiguous input, the fast path now keeps a pointer to the token in the
input, and get_string() copies it on first use. The parser passes an empty
string to the handlers marked by the new internal trait
sax_ignores_number_text instead of calling get_string(), so json::parse()
and json::accept() never copy float text. User handlers, and
JSON_DIAGNOSTIC_POSITIONS (which reads get_string().size()), still see the
exact text. Keys and strings, which never have pending text, use the
unchecked get_string_token(). Input read through a window into a stream
(std::istream, FILE*) copies the text right away, because the next read may
refill the window.

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

.github/workflows/windows.yml

@@ -166,19 +166,21 @@ jobs:
       # link, but the binaries clang 11.0.1 and clang 18.1.8 then produce crash
       # before doctest prints its first line - 39 of 102 tests on clang 18.
       # Keep the objects small by splitting the test files instead.
-      # Objects with more than 65535 sections fail to link with "relocation
-      # truncated to fit: IMAGE_REL_AMD64_REL32 against `.rdata'": the MinGW
-      # linker stores the section an associative COMDAT section belongs to in
-      # 16 bits (x_associated in binutils' include/coff/internal.h), so it
-      # discards the jump tables of inline functions together with the wrong
-      # function. Each basic_json specialization a test file instantiates adds
-      # many sections, so test a second one in a file of its own.
+      # The tests link with LLD: GNU ld fails on objects with more than 32767
+      # sections with "relocation truncated to fit: IMAGE_REL_AMD64_REL32
+      # against `.rdata'", as it stores the section an associative COMDAT
+      # section belongs to in 16 bits (x_associated in binutils'
+      # include/coff/internal.h) and so discards the jump tables of inline
+      # functions together with the wrong function. Each basic_json
+      # specialization and input type a test file instantiates adds many
+      # sections, so unit-msgpack.cpp and unit-regression2.cpp kept crossing
+      # that limit as the library grew.
       - name: Run CMake
         run: cmake -S . -B build ^
              -DCMAKE_CXX_COMPILER="C:/Program Files/LLVM/bin/clang++.exe" ^
              -DCMAKE_CXX_FLAGS="--target=x86_64-w64-mingw32 -stdlib=libstdc++ -pthread" ^
              -DCMAKE_CXX_FLAGS_DEBUG="-g0" ^
-             -DCMAKE_EXE_LINKER_FLAGS="-lwinpthread" ^
+             -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld -lwinpthread" ^
              -G"MinGW Makefiles" ^
              -DCMAKE_BUILD_TYPE=Debug ^
              -DJSON_BuildTests=On

BUILD.bazel

@@ -36,7 +36,6 @@ cc_library(
         "include/nlohmann/detail/input/parser.hpp",
         "include/nlohmann/detail/input/position_t.hpp",
         "include/nlohmann/detail/input/pow5_table.hpp",
-        "include/nlohmann/detail/input/simd_scan.hpp",
         "include/nlohmann/detail/input/string_scan.hpp",
         "include/nlohmann/detail/iterators/internal_iterator.hpp",
         "include/nlohmann/detail/iterators/iter_impl.hpp",

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

@@ -38,7 +38,6 @@ header. See also the [macro overview page](../../features/macros.md).
 - [**JSON_HAS_THREE_WAY_COMPARISON**](json_has_three_way_comparison.md) - control 3-way comparison support
 - [**JSON_NO_AUTOMATIC_UDLS**](json_no_automatic_udls.md) - do not include the user-defined string literals (UDLs) automatically
 - [**JSON_NO_IO**](json_no_io.md) - switch off functions relying on certain C++ I/O headers
-- [**JSON_NO_SIMD**](json_no_simd.md) - use only portable code instead of vector instructions (SSE2, SSSE3, NEON)
 - [**JSON_NO_THREAD_LOCAL**](json_no_thread_local.md) - switch off the use of `thread_local` storage
 - [**JSON_SKIP_UNSUPPORTED_COMPILER_CHECK**](json_skip_unsupported_compiler_check.md) - do not warn about unsupported compilers
 - [**JSON_USE_GLOBAL_UDLS**](json_use_global_udls.md) - place user-defined string literals (UDLs) into the global namespace

docs/mkdocs/docs/api/macros/json_disable_stream_bulk_scan.md

@@ -69,12 +69,11 @@ The default value is `0`: streams are scanned in bulk.
     changes the characters in its get area in place, does not meet these requirements. Define the macro to `1` for
     such stream buffers.
 
-!!! warning "Define consistently"
+!!! note "ABI compatibility"
 
-    The macro selects between two definitions of the library's internal stream input adapter. It must therefore be
-    defined identically for **every** translation unit that includes the library; mixing translation units that define
-    it with ones that do not is an ODR violation. Prefer setting it as a compile definition on the target rather than
-    with `#!cpp #define` in individual source files.
+    The value of this macro is encoded in the [namespace](../../features/namespace.md) (tag `_dsbs`), resulting in
+    distinct symbol names. Translation units compiled with and without it can therefore be linked into the same program
+    without One Definition Rule (ODR) violations, but they cannot exchange instances of library types.
 
 !!! note "Other inputs"
 

docs/mkdocs/docs/api/macros/json_disable_unlocked_file_io.md

@@ -49,12 +49,11 @@ The default value is `0`: the file is locked once and read with the unlocked std
     A program in which a SAX handler or parser callback waits for **another** thread that uses the **same** `FILE`
     object would deadlock. Define the macro to `1` for such programs.
 
-!!! warning "Define consistently"
+!!! note "ABI compatibility"
 
-    The macro selects between two definitions of the library's internal `FILE*` input adapter. It must therefore be
-    defined identically for **every** translation unit that includes the library; mixing translation units that define
-    it with ones that do not is an ODR violation (and can leave a file locked). Prefer setting it as a compile
-    definition on the target rather than with `#!cpp #define` in individual source files.
+    The value of this macro is encoded in the [namespace](../../features/namespace.md) (tag `_dufio`), resulting in
+    distinct symbol names. Translation units compiled with and without it can therefore be linked into the same program
+    without One Definition Rule (ODR) violations, but they cannot exchange instances of library types.
 
 !!! note "Other inputs"
 

docs/mkdocs/docs/api/macros/json_no_simd.md

@@ -1,83 +0,0 @@
-# JSON_NO_SIMD
-
-```cpp
-#define JSON_NO_SIMD
-```
-
-When defined, the library uses only portable C++ code where it would otherwise use vector instructions: when scanning
-strings during parsing, and when writing floating-point numbers during serialization.
-
-The macro is an escape hatch, for example for toolchains that cannot compile the vector code, for sanitizers or
-analyzers that do not understand it, or to compare the speed of both variants. It does not change any result: values,
-exceptions, and error positions are the same either way. Only the speed differs.
-
-## Default definition
-
-By default, `#!cpp JSON_NO_SIMD` is not defined, and vector instructions are used where the target has them.
-
-```cpp
-#undef JSON_NO_SIMD
-```
-
-## Notes
-
-!!! note "Which instructions are used"
-
-    - **x86-64:** SSE2, which every x86-64 CPU has, finds the end of runs of plain string characters 16 bytes at a time
-      and writes the digits of floating-point numbers. The UTF-8 check of non-ASCII text needs SSSE3, which is not part
-      of x86-64: it is compiled for SSSE3 with a function attribute and used when the CPU has SSSE3 (every x86-64 CPU
-      since about 2011), else the portable check. Code compiled for SSSE3 anyway (e.g., with `-mssse3` or `-march=native`)
-      skips this check of the CPU. 32-bit x86 uses SSE2 for strings when the compiler targets it.
-    - **AArch64:** NEON, which every 64-bit Arm CPU has, checks UTF-8 text and long runs of plain string characters 16
-      bytes at a time, and writes the digits of floating-point numbers. With MSVC, only the floating-point digits use
-      NEON.
-    - **Other targets:** portable code only.
-
-    Strings are only scanned this way for contiguous input and for the characters a `#!cpp std::istream` holds in its
-    stream buffer (see [`JSON_DISABLE_STREAM_BULK_SCAN`](json_disable_stream_bulk_scan.md)); other inputs are read one
-    character at a time.
-
-!!! note "Interaction with `JSON_USE_SIMDUTF`"
-
-    With [`JSON_USE_SIMDUTF`](json_use_simdutf.md), runs of string characters are first validated by simdutf; the code
-    described here is used for what simdutf does not accept, so that errors are reported at the same position.
-    `JSON_NO_SIMD` does not affect simdutf.
-
-!!! warning "Define consistently"
-
-    The macro selects between two definitions of the library's internal scanning and formatting functions. It must
-    therefore be defined identically for **every** translation unit that includes the library; mixing translation units
-    that define it with ones that do not is an ODR violation. Prefer setting it as a compile definition on the target
-    rather than with `#!cpp #define` in individual source files.
-
-## Examples
-
-??? example "Example: switching off vector instructions"
-
-    The program parses and serializes the same values with and without the macro:
-
-    ```cpp
-    #define JSON_NO_SIMD
-    #include <iostream>
-    #include <nlohmann/json.hpp>
-
-    using json = nlohmann::json;
-
-    int main()
-    {
-        const json j = json::parse(R"({"name": "日本語 text", "pi": 3.141592653589793})");
-        std::cout << j.dump() << '\n';  // {"name":"日本語 text","pi":3.141592653589793}
-    }
-    ```
-
-## See also
-
-- [**parse**](../basic_json/parse.md) - deserialize from a compatible input
-- [**dump**](../basic_json/dump.md) - serialization
-- [**JSON_USE_SIMDUTF**](json_use_simdutf.md) - use the simdutf library to accelerate UTF-8 validation
-- [**JSON_DISABLE_STREAM_BULK_SCAN**](json_disable_stream_bulk_scan.md) - read a `std::istream` one character at a time
-- [Parsing: input sources and performance](../../features/parsing/index.md#input-sources-and-performance)
-
-## Version history
-
-- Added in version 3.13.0.

docs/mkdocs/docs/api/macros/json_use_simdutf.md

@@ -6,9 +6,8 @@
 
 When defined, the parser validates the UTF-8 content of JSON strings that come from a **contiguous byte input**
 (`std::string`, `std::vector<char>`/`<std::uint8_t>`, string literals, `const char*` ranges, …) using the
-[simdutf](https://github.com/simdutf/simdutf) library instead of the built-in validator (which uses SSSE3 or NEON where
-available, see [`JSON_NO_SIMD`](json_no_simd.md)). On text with many non-ASCII characters (e.g. CJK or emoji) this can
-validate faster, depending on the CPU.
+[simdutf](https://github.com/simdutf/simdutf) library instead of the built-in scalar validator. On text with many
+non-ASCII characters (e.g. CJK or emoji) this can validate several times faster.
 
 This is an **opt-in external dependency**. The library itself remains header-only and its behavior is unchanged: the
 same input is accepted or rejected either way, and every parse error is reported at the same position with the same

docs/mkdocs/docs/api/macros/nlohmann_json_namespace.md

@@ -39,5 +39,6 @@ the library.
 ## Version history
 
 - Added in version 3.11.0. Changed inline namespace name in version 3.11.2. Added the ABI tag `_dp` in
-  version 3.12.0, and the ABI tags `_bics`, `_psp`, `_snul`, `_sbu8`, and `_ekmo` in version 3.13.0; see
+  version 3.12.0, and the ABI tags `_bics`, `_psp`, `_snul`, `_sbu8`, `_ekmo`, `_dsbs`, and `_dufio` in version
+  3.13.0; see
   [`nlohmann` Namespace](../../features/namespace.md#structure).

docs/mkdocs/docs/features/macros.md

@@ -174,13 +174,6 @@ security reasons (e.g., Intel Software Guard Extensions (SGX)).
 
 See [full documentation of `JSON_NO_IO`](../api/macros/json_no_io.md).
 
-## `JSON_NO_SIMD`
-
-When defined, the library uses only portable code instead of vector instructions (SSE2, SSSE3, NEON) for scanning
-strings and writing floating-point numbers. Results are the same either way. It is not defined by default.
-
-See [full documentation of `JSON_NO_SIMD`](../api/macros/json_no_simd.md).
-
 ## `JSON_NO_THREAD_LOCAL`
 
 When defined, the library does not use `#!cpp thread_local` storage. Copying a value and comparing two values then

docs/mkdocs/docs/features/namespace.md

@@ -23,6 +23,10 @@ The complete default namespace name is derived as follows:
     - [`JSON_STRICT_BINARY_UTF8`](../api/macros/json_strict_binary_utf8.md) defined non-zero appends `_sbu8`.
     - [`JSON_USE_OBJECTS_FOR_ENUM_KEYED_MAPS`](../api/macros/json_use_objects_for_enum_keyed_maps.md) defined non-zero
       appends `_ekmo`.
+    - [`JSON_DISABLE_STREAM_BULK_SCAN`](../api/macros/json_disable_stream_bulk_scan.md) defined non-zero appends
+      `_dsbs`.
+    - [`JSON_DISABLE_UNLOCKED_FILE_IO`](../api/macros/json_disable_unlocked_file_io.md) defined non-zero appends
+      `_dufio`.
 - The inline namespace ends with the suffix `_v` followed by the 3 components of the version number separated by
   underscores. To omit the version component, see [Disabling the version component](#disabling-the-version-component)
   below.
@@ -105,5 +109,7 @@ follows:
 - Added ABI tags `_bics` ([`JSON_BRACE_INIT_COPY_SEMANTICS`](../api/macros/json_brace_init_copy_semantics.md)), `_psp`
   ([`JSON_PRECISE_STREAM_POSITION`](../api/macros/json_precise_stream_position.md)), `_snul`
   ([`JSON_STRICT_NUL_HANDLING`](../api/macros/json_strict_nul_handling.md)), `_sbu8`
-  ([`JSON_STRICT_BINARY_UTF8`](../api/macros/json_strict_binary_utf8.md)), and `_ekmo`
-  ([`JSON_USE_OBJECTS_FOR_ENUM_KEYED_MAPS`](../api/macros/json_use_objects_for_enum_keyed_maps.md)) in version 3.13.0.
+  ([`JSON_STRICT_BINARY_UTF8`](../api/macros/json_strict_binary_utf8.md)), `_ekmo`
+  ([`JSON_USE_OBJECTS_FOR_ENUM_KEYED_MAPS`](../api/macros/json_use_objects_for_enum_keyed_maps.md)), `_dsbs`
+  ([`JSON_DISABLE_STREAM_BULK_SCAN`](../api/macros/json_disable_stream_bulk_scan.md)), and `_dufio`
+  ([`JSON_DISABLE_UNLOCKED_FILE_IO`](../api/macros/json_disable_unlocked_file_io.md)) in version 3.13.0.

docs/mkdocs/docs/features/parsing/index.md

@@ -79,10 +79,6 @@ follow the usual `std::streambuf` contract, and
 [`JSON_DISABLE_UNLOCKED_FILE_IO`](../../api/macros/json_disable_unlocked_file_io.md) for programs in which another
 thread must use the same `#!cpp FILE` object while it is parsed.
 
-Where the target has them, strings are scanned with vector instructions: SSE2 on x86-64 (and SSSE3 for UTF-8 text, when
-the CPU has it) and NEON on AArch64. [`JSON_NO_SIMD`](../../api/macros/json_no_simd.md) selects portable code instead,
-again without changing any result.
-
 ## SAX vs. DOM parsing
 
 The library offers two parsing models:

docs/mkdocs/docs/home/architecture.md

@@ -59,7 +59,7 @@ below are relative to `include/nlohmann`.
 |-----------|----------|
 | Value type enumeration | [`detail/value_t.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/value_t.hpp) |
 | Input adapters | [`detail/input/input_adapters.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/input_adapters.hpp) |
-| Lexer | [`detail/input/lexer.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/lexer.hpp), [`detail/input/number_parse.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/number_parse.hpp), [`detail/input/string_scan.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/string_scan.hpp), [`detail/input/simd_scan.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/simd_scan.hpp) |
+| Lexer | [`detail/input/lexer.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/lexer.hpp), [`detail/input/number_parse.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/number_parse.hpp), [`detail/input/string_scan.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/string_scan.hpp) |
 | Parser | [`detail/input/parser.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/parser.hpp) |
 | SAX interface and DOM builders | [`detail/input/json_sax.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/json_sax.hpp) |
 | Binary format readers | [`detail/input/binary_reader.hpp`](https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/binary_reader.hpp) |

docs/mkdocs/mkdocs.yml

@@ -310,7 +310,6 @@ nav:
           - 'JSON_NO_AUTOMATIC_UDLS': api/macros/json_no_automatic_udls.md
           - 'JSON_NOEXCEPTION': api/macros/json_noexception.md
           - 'JSON_NO_IO': api/macros/json_no_io.md
-          - 'JSON_NO_SIMD': api/macros/json_no_simd.md
           - 'JSON_NO_THREAD_LOCAL': api/macros/json_no_thread_local.md
           - 'JSON_PRECISE_STREAM_POSITION': api/macros/json_precise_stream_position.md
           - 'JSON_SKIP_LIBRARY_VERSION_CHECK': api/macros/json_skip_library_version_check.md

include/nlohmann/detail/abi_macros.hpp

@@ -54,6 +54,14 @@
     #define JSON_USE_OBJECTS_FOR_ENUM_KEYED_MAPS 0
 #endif
 
+#ifndef JSON_DISABLE_STREAM_BULK_SCAN
+    #define JSON_DISABLE_STREAM_BULK_SCAN 0
+#endif
+
+#ifndef JSON_DISABLE_UNLOCKED_FILE_IO
+    #define JSON_DISABLE_UNLOCKED_FILE_IO 0
+#endif
+
 #if JSON_DIAGNOSTICS
     #define NLOHMANN_JSON_ABI_TAG_DIAGNOSTICS _diag
 #else
@@ -102,14 +110,26 @@
     #define NLOHMANN_JSON_ABI_TAG_OBJECTS_FOR_ENUM_KEYED_MAPS
 #endif
 
+#if JSON_DISABLE_STREAM_BULK_SCAN
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_STREAM_BULK_SCAN _dsbs
+#else
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_STREAM_BULK_SCAN
+#endif
+
+#if JSON_DISABLE_UNLOCKED_FILE_IO
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_UNLOCKED_FILE_IO _dufio
+#else
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_UNLOCKED_FILE_IO
+#endif
+
 #ifndef NLOHMANN_JSON_NAMESPACE_NO_VERSION
     #define NLOHMANN_JSON_NAMESPACE_NO_VERSION 0
 #endif
 
 // Construct the namespace ABI tags component
-#define NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h) json_abi ## a ## b ## c ## d ## e ## f ## g ## h
-#define NLOHMANN_JSON_ABI_TAGS_CONCAT(a, b, c, d, e, f, g, h) \
-    NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h)
+#define NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h, i, j) json_abi ## a ## b ## c ## d ## e ## f ## g ## h ## i ## j
+#define NLOHMANN_JSON_ABI_TAGS_CONCAT(a, b, c, d, e, f, g, h, i, j) \
+    NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h, i, j)
 
 #define NLOHMANN_JSON_ABI_TAGS                                       \
     NLOHMANN_JSON_ABI_TAGS_CONCAT(                                   \
@@ -120,7 +140,9 @@
             NLOHMANN_JSON_ABI_TAG_PRECISE_STREAM_POSITION,           \
             NLOHMANN_JSON_ABI_TAG_STRICT_NUL_HANDLING,               \
             NLOHMANN_JSON_ABI_TAG_STRICT_BINARY_UTF8,                \
-            NLOHMANN_JSON_ABI_TAG_OBJECTS_FOR_ENUM_KEYED_MAPS)
+            NLOHMANN_JSON_ABI_TAG_OBJECTS_FOR_ENUM_KEYED_MAPS,       \
+            NLOHMANN_JSON_ABI_TAG_DISABLE_STREAM_BULK_SCAN,          \
+            NLOHMANN_JSON_ABI_TAG_DISABLE_UNLOCKED_FILE_IO)
 
 // Construct the namespace version component
 #define NLOHMANN_JSON_NAMESPACE_VERSION_CONCAT_EX(major, minor, patch) \

include/nlohmann/detail/conversions/to_chars.hpp

@@ -23,12 +23,12 @@
 #endif
 
 // SSE2 (every x86-64 CPU) and NEON (every 64-bit Arm CPU) convert the 16
-// digits of a double at once (unless JSON_NO_SIMD selects the portable code)
-#if !defined(JSON_NO_SIMD) && (defined(__x86_64__) || (defined(_M_X64) && !defined(_M_ARM64EC)))
+// digits of a double at once
+#if defined(__x86_64__) || (defined(_M_X64) && !defined(_M_ARM64EC))
     #include <emmintrin.h>
     #define JSON_DTOA_SSE2 1
     #define JSON_DTOA_NEON 0
-#elif !defined(JSON_NO_SIMD) && (defined(__aarch64__) || defined(_M_ARM64)) && !defined(_M_ARM64EC) && !defined(__ARM_BIG_ENDIAN)
+#elif (defined(__aarch64__) || defined(_M_ARM64)) && !defined(_M_ARM64EC) && !defined(__ARM_BIG_ENDIAN)
     #include <arm_neon.h>
     #define JSON_DTOA_SSE2 0
     #define JSON_DTOA_NEON 1

include/nlohmann/detail/conversions/to_json.hpp

@@ -13,7 +13,7 @@
     #include <optional> // optional
 #endif
 
-#include <iterator> // begin, end
+#include <iterator> // begin, end, make_move_iterator, move_iterator
 #include <memory> // allocator_traits
 #include <string> //  basic_string, char_traits
 #include <tuple> // tuple, get
@@ -48,6 +48,32 @@ namespace detail
  * leave j with the type of the new value, but the pointer to the destroyed old one.
  */
 
+// a move iterator over the elements of an rvalue container, unless they are
+// const (e.g., std::set): libstdc++ before GCC 5 defines the reference of a
+// std::move_iterator as value_type&&, which cannot bind to a const element
+template<typename Iterator>
+std::move_iterator<Iterator> make_move_iterator_if_mutable_impl(const Iterator& it, std::true_type /*mutable*/)
+{
+    return std::make_move_iterator(it);
+}
+
+template<typename Iterator>
+Iterator make_move_iterator_if_mutable_impl(const Iterator& it, std::false_type /*mutable*/)
+{
+    return it;
+}
+
+template<typename Iterator>
+using is_mutable_iterator = std::integral_constant < bool,
+      !std::is_const<typename std::remove_reference<decltype(*std::declval<Iterator&>())>::type>::value >;
+
+template<typename Iterator>
+auto make_move_iterator_if_mutable(const Iterator& it)
+-> decltype(make_move_iterator_if_mutable_impl(it, is_mutable_iterator<Iterator> {}))
+{
+    return make_move_iterator_if_mutable_impl(it, is_mutable_iterator<Iterator> {});
+}
+
 template<value_t> struct external_constructor;
 
 template<>
@@ -174,7 +200,7 @@ struct external_constructor<value_t::array>
         using std::begin;
         using std::end;
 
-        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::array_t>(std::make_move_iterator(begin(arr)), std::make_move_iterator(end(arr))));
+        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::array_t>(make_move_iterator_if_mutable(begin(arr)), make_move_iterator_if_mutable(end(arr))));
         j.replace_value(value_t::array, value);
     }
 
@@ -235,7 +261,7 @@ struct external_constructor<value_t::object>
         using std::begin;
         using std::end;
 
-        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::object_t>(std::make_move_iterator(begin(obj)), std::make_move_iterator(end(obj))));
+        const typename BasicJsonType::json_value value(j.template create<typename BasicJsonType::object_t>(make_move_iterator_if_mutable(begin(obj)), make_move_iterator_if_mutable(end(obj))));
         j.replace_value(value_t::object, value);
     }
 
@@ -413,25 +439,27 @@ using is_movable_container_rvalue = negation<disjunction<
                                     std::is_const<T>,
                                     has_dedicated_to_json<T>,
                                     is_basic_json<T>,
-                                    is_range_view_type<T>,
                                     is_enum_keyed_map_type<T>,
                                     std::is_same<T, std::vector<bool>>>>;
 
-// rvalue array-like containers
+// rvalue array-like containers; object types are ruled out before views are
+// checked, as std::ranges::view<T> for the object_t of an ordered_json would
+// need that ordered_json to be complete (GCC 11, see #3312)
 template<typename BasicJsonType, typename T>
 using is_rvalue_array_to_json = conjunction<is_movable_container_rvalue<T>,
+      negation<is_compatible_object_type<BasicJsonType, T>>,
+      negation<is_range_view_type<T>>,
       is_compatible_array_type<BasicJsonType, T>,
       negation<disjunction<
       std::is_same<T, typename BasicJsonType::array_t>,
       std::is_same<T, typename BasicJsonType::binary_t>,
-      is_compatible_object_type<BasicJsonType, T>,
       is_compatible_string_type<BasicJsonType, T>,
       is_compatible_binary_type<BasicJsonType, T>>>>;
 
 // rvalue containers: their elements are moved instead of copied
 template<typename BasicJsonType, typename CompatibleArrayType,
          enable_if_t<is_rvalue_array_to_json<BasicJsonType, CompatibleArrayType>::value, int> = 0>
-inline void to_json(BasicJsonType& j, CompatibleArrayType && arr)
+inline void to_json(BasicJsonType& j, CompatibleArrayType && arr) // NOLINT(cppcoreguidelines-missing-std-forward)
 {
     external_constructor<value_t::array>::construct_moving(j, arr);
 }
@@ -509,7 +537,8 @@ inline void to_json(BasicJsonType& j, const EnumKeyedMap& map)
 }
 #endif
 
-// rvalue object-like containers
+// rvalue object-like containers (views have no key_type and mapped_type, so
+// they are no compatible object type)
 template<typename BasicJsonType, typename T>
 using is_rvalue_object_to_json = conjunction<is_movable_container_rvalue<T>,
       negation<std::is_same<T, typename BasicJsonType::object_t>>,
@@ -517,7 +546,7 @@ using is_rvalue_object_to_json = conjunction<is_movable_container_rvalue<T>,
 
 template<typename BasicJsonType, typename CompatibleObjectType,
          enable_if_t<is_rvalue_object_to_json<BasicJsonType, CompatibleObjectType>::value, int> = 0>
-inline void to_json(BasicJsonType& j, CompatibleObjectType && obj)
+inline void to_json(BasicJsonType& j, CompatibleObjectType && obj) // NOLINT(cppcoreguidelines-missing-std-forward)
 {
     external_constructor<value_t::object>::construct_moving(j, obj);
 }

include/nlohmann/detail/conversions/zmij.hpp

@@ -185,7 +185,7 @@ JSON_HEDLEY_ALWAYS_INLINE shortest_decimal to_shortest(std::uint64_t bits) noexc
     const uint128_parts p = umul192_hi128(p10.high, p10.low, bin_sig << static_cast<unsigned>(shift));
     std::uint64_t integral = p.high >> static_cast<unsigned>(extra_shift);
     // (no casts in the shifts: MSVC 2015 warns C4554 on them despite the parentheses)
-    constexpr unsigned fractional_low_shift = static_cast<unsigned>(extra_shift);
+    constexpr auto fractional_low_shift = static_cast<unsigned>(extra_shift);
     constexpr unsigned fractional_high_shift = 64u - fractional_low_shift;
     const std::uint64_t fractional = (p.high << fractional_high_shift) | (p.low >> fractional_low_shift);
     std::uint64_t digit = 0;

include/nlohmann/detail/exceptions.hpp

@@ -494,8 +494,7 @@ JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE void throw_patch_missing_member(c
     static_cast<void>(string_type);
     static_cast<void>(val);
     // context-sensitive error message
-    const std::string error_msg = (op == "op") ? std::string("operation") : concat("operation '", op, '\'');
-    JSON_THROW(parse_error::create(exception_id::patch_invalid_operation, 0, concat(error_msg, string_type ? " must have string member '" : " must have member '", member, "'"), &val));
+    JSON_THROW(parse_error::create(exception_id::patch_invalid_operation, 0, concat((op == "op") ? std::string("operation") : concat("operation '", op, '\''), string_type ? " must have string member '" : " must have member '", member, "'"), &val));
 }
 
 template<typename StringType, typename BasicJsonType>

include/nlohmann/detail/input/input_adapters.hpp

@@ -91,10 +91,7 @@ class file_input_adapter
     file_input_adapter& operator=(file_input_adapter&&) = delete;
     ~file_input_adapter()
     {
-        if (m_file != nullptr)
-        {
-            unlock();
-        }
+        unlock();
     }
 
     std::char_traits<char>::int_type get_character() noexcept
@@ -132,6 +129,11 @@ class file_input_adapter
 
     void unlock() noexcept
     {
+        // a moved-from adapter has no file and holds no lock
+        if (m_file == nullptr)
+        {
+            return;
+        }
 #if JSON_UNLOCKED_FILE_IO == 1
         funlockfile(m_file);
 #elif JSON_UNLOCKED_FILE_IO == 2

include/nlohmann/detail/input/lexer.hpp

@@ -12,7 +12,6 @@
 #include <cstddef> // size_t
 #include <cstdint> // uint32_t
 #include <cstdio> // snprintf
-#include <cstring> // memcmp
 #include <initializer_list> // initializer_list
 #include <string> // char_traits, string
 #include <utility> // move
@@ -418,43 +417,30 @@ class lexer : public lexer_base<BasicJsonType>
     }
 
     /// contiguous input: bulk-append the run of ordinary characters and complete
-    /// well-formed UTF-8 sequences starting at the current read position, then
-    /// read the first byte that needs individual handling (the closing quote, an
-    /// escape, a control character, or an ill-formed UTF-8 byte) like get().
-    /// That byte is taken from the buffer that was just scanned. Through get(),
-    /// Apple Clang merged this read with the other get() calls of the scan
-    /// function, which load the read position again right after it was stored
-    /// (3% of json::accept() on jeopardy.json on Apple M1).
-    char_int_type get_after_string_run(std::true_type /*bulk*/)
+    /// well-formed UTF-8 sequences starting at the current read position, leaving
+    /// the first byte that needs individual handling (the closing quote, an
+    /// escape, a control character, or an ill-formed UTF-8 byte) for get()
+    void scan_string_bulk(std::true_type /*bulk*/)
     {
         // a pending unget must be consumed through the normal path first
         if (next_unget)
         {
-            return get();
+            return;
         }
         const std::size_t remaining = ia.bulk_remaining();
         if (remaining == 0)
         {
-            return get();
+            return;
         }
-        const auto* const raw = ia.bulk_data();
-        const auto* const data = reinterpret_cast<const unsigned char*>(raw);
+        const auto* const data = reinterpret_cast<const unsigned char*>(ia.bulk_data());
 
-        const std::size_t pos = lexer_string_bulk_run(data, remaining);
-        if (pos != 0)
+        const std::size_t pos = string_bulk_run(data, remaining);
+        if (pos == 0)
         {
-            token_buffer.append(reinterpret_cast<const typename string_t::value_type*>(data), pos);
-            bulk_consume(reinterpret_cast<const char*>(data), pos);
+            return;
         }
-        if (pos == remaining)
-        {
-            return get(); // end of the contiguous input
-        }
-        // what get() does, with the byte at hand
-        advance_position();
-        ia.bulk_skip(1);
-        current = char_traits<char_type>::to_int_type(raw[pos]);
-        return track_after_read();
+        token_buffer.append(reinterpret_cast<const typename string_t::value_type*>(data), pos);
+        bulk_consume(reinterpret_cast<const char*>(data), pos);
     }
 
     /// consume @a n characters at @a data (the adapter's bulk_data()) and do
@@ -487,10 +473,7 @@ class lexer : public lexer_base<BasicJsonType>
     }
 
     /// streaming input: no bulk fast path
-    char_int_type get_after_string_run(std::false_type /*bulk*/)
-    {
-        return get();
-    }
+    void scan_string_bulk(std::false_type /*bulk*/) const noexcept {}
 
     /*!
     @brief scan a string literal
@@ -518,8 +501,11 @@ class lexer : public lexer_base<BasicJsonType>
         while (true)
         {
             // bulk-consume ordinary characters from contiguous input, then
-            // get the next character, the one that ends the run
-            switch (get_after_string_run(std::integral_constant<bool, bulk_scan>()))
+            // handle the next special byte through the switch below
+            scan_string_bulk(std::integral_constant<bool, bulk_scan> {});
+
+            // get the next character
+            switch (get())
             {
                 // end of file while parsing the string
                 case char_traits<char_type>::eof():
@@ -1855,23 +1841,18 @@ scan_number_done:
     }
 
     /*!
-    @param[in] rest         the literal text after its first character, which
-                            is current (its length is a template parameter, so
-                            that the comparison of the contiguous fast path is
-                            a fixed-size load, not a call of memcmp)
-    @param[in] return_type  the token type to return on success
+    @param[in] literal_text  the literal text to expect
+    @param[in] length        the length of the passed literal text
+    @param[in] return_type   the token type to return on success
     */
-    template<std::size_t N>
-    JSON_HEDLEY_NEVER_INLINE token_type scan_literal(const char (&rest)[N], token_type return_type)
+    JSON_HEDLEY_NON_NULL(2)
+    token_type scan_literal(const char_type* literal_text, const std::size_t length,
+                            token_type return_type)
     {
-        constexpr std::size_t length = N - 1;
-        if (scan_literal_bulk(rest, length, std::integral_constant<bool, bulk_scan> {}))
+        JSON_ASSERT(char_traits<char_type>::to_char_type(current) == literal_text[0]);
+        for (std::size_t i = 1; i < length; ++i)
         {
-            return return_type;
-        }
-        for (std::size_t i = 0; i < length; ++i)
-        {
-            if (JSON_HEDLEY_UNLIKELY(char_traits<char_type>::to_char_type(get()) != static_cast<char_type>(rest[i])))
+            if (JSON_HEDLEY_UNLIKELY(char_traits<char_type>::to_char_type(get()) != literal_text[i]))
             {
                 error_message = "invalid literal";
                 return token_type::parse_error;
@@ -1880,27 +1861,6 @@ scan_number_done:
         return return_type;
     }
 
-    /// contiguous input: compare the rest of a literal at once; false (and
-    /// nothing consumed) if it does not match, so that the byte path reports
-    /// the error at the right character
-    JSON_HEDLEY_ALWAYS_INLINE bool scan_literal_bulk(const char* rest, const std::size_t length, std::true_type /*bulk*/)
-    {
-        if (next_unget || ia.bulk_remaining() < length
-                || std::memcmp(ia.bulk_data(), rest, length) != 0)
-        {
-            return false;
-        }
-        bulk_consume(reinterpret_cast<const char*>(ia.bulk_data()), length);
-        current = static_cast<char_int_type>(static_cast<unsigned char>(rest[length - 1]));
-        return true;
-    }
-
-    /// streaming input: no bulk fast path
-    bool scan_literal_bulk(const char* /*rest*/, const std::size_t /*length*/, std::false_type /*bulk*/) const noexcept
-    {
-        return false;
-    }
-
     /////////////////////
     // input management
     /////////////////////
@@ -2526,14 +2486,21 @@ scan_number_done:
                 return token_type::value_separator;
 
             // literals
-            // (the text after the first character; no local arrays, which
-            // would give this function a stack canary on every token)
             case 't':
-                return scan_literal("rue", token_type::literal_true);
+            {
+                std::array<char_type, 4> true_literal = {{static_cast<char_type>('t'), static_cast<char_type>('r'), static_cast<char_type>('u'), static_cast<char_type>('e')}};
+                return scan_literal(true_literal.data(), true_literal.size(), token_type::literal_true);
+            }
             case 'f':
-                return scan_literal("alse", token_type::literal_false);
+            {
+                std::array<char_type, 5> false_literal = {{static_cast<char_type>('f'), static_cast<char_type>('a'), static_cast<char_type>('l'), static_cast<char_type>('s'), static_cast<char_type>('e')}};
+                return scan_literal(false_literal.data(), false_literal.size(), token_type::literal_false);
+            }
             case 'n':
-                return scan_literal("ull", token_type::literal_null);
+            {
+                std::array<char_type, 4> null_literal = {{static_cast<char_type>('n'), static_cast<char_type>('u'), static_cast<char_type>('l'), static_cast<char_type>('l')}};
+                return scan_literal(null_literal.data(), null_literal.size(), token_type::literal_null);
+            }
 
             // string
             case '\"':

include/nlohmann/detail/input/parser.hpp

@@ -244,9 +244,8 @@ class parser
     bool sax_parse_internal(SAX* sax)
     {
         // stack to remember the hierarchy of structured values we are parsing
-        // true = array; false = object (bytes, not std::vector<bool>, whose
-        // push_back() is a call with GCC)
-        std::vector<std::uint8_t> states;
+        // true = array; false = object
+        std::vector<bool> states;
         // value to avoid a goto (see comment where set to true)
         bool skip_to_state_evaluation = false;
 
@@ -291,7 +290,7 @@ class parser
                         }
 
                         // remember we are now inside an object
-                        states.push_back(0);
+                        states.push_back(false);
 
                         // parse values
                         get_token();
@@ -316,7 +315,7 @@ class parser
                         }
 
                         // remember we are now inside an array
-                        states.push_back(1);
+                        states.push_back(true);
 
                         // parse values (no need to call get_token)
                         continue;
@@ -433,7 +432,7 @@ class parser
                 return true;
             }
 
-            if (states.back() != 0)  // array
+            if (states.back())  // array
             {
                 // comma -> next value
                 // or end of array (ignore_trailing_commas = true)

include/nlohmann/detail/input/simd_scan.hpp

@@ -1,314 +0,0 @@
-//     __ _____ _____ _____
-//  __|  |   __|     |   | |  JSON for Modern C++
-// |  |  |__   |  |  | | | |  version 3.12.0
-// |_____|_____|_____|_|___|  https://github.com/nlohmann/json
-//
-// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
-// SPDX-FileCopyrightText: 2018-2025 The simdjson authors <https://github.com/simdjson/simdjson>
-// SPDX-License-Identifier: MIT
-
-#pragma once
-
-#include <array> // array
-#include <atomic> // atomic
-#include <cstddef> // size_t
-#include <cstdint> // uint8_t, uint64_t
-
-#include <nlohmann/detail/bit_ops.hpp>
-#include <nlohmann/detail/macro_scope.hpp>
-
-// Vector code for runs of string bytes, used by the lexer for contiguous input
-// (see string_bulk_run()). NEON (AArch64) and SSE2 (x86-64) belong to the
-// baseline instruction sets and are used by default. The vector UTF-8 check
-// needs NEON or SSSE3. SSSE3 is not part of x86-64, and the code must not
-// depend on the flags of a translation unit (two translation units with
-// different flags would have different definitions of the same inline
-// functions): the check is compiled for SSSE3 with a function attribute and
-// used where the CPU has SSSE3 (all x86-64 CPUs since about 2011), else the
-// portable check. Code compiled for SSSE3 anyway (-mssse3 or more) skips the
-// CPU check. JSON_NO_SIMD selects the portable code everywhere.
-// NLOHMANN_JSON_NO_TARGET_ATTRIBUTE (for compilers that ignore the target
-// attribute and then reject the SSSE3 intrinsics) keeps the check portable
-// without disabling the SSE2 code.
-#if !defined(JSON_NO_SIMD) && defined(__aarch64__) && (defined(__GNUC__) || defined(__clang__)) && defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    #include <arm_neon.h>
-    #define JSON_SCAN_NEON 1
-#else
-    #define JSON_SCAN_NEON 0
-#endif
-// (x86 only: other targets can define __SSE2__ as well, e.g., WebAssembly with -msse2, but have no <cpuid.h>)
-#if !defined(JSON_NO_SIMD) && !JSON_SCAN_NEON && (defined(__x86_64__) || defined(__i386__) || defined(_M_X64) || defined(_M_IX86)) && !defined(_M_ARM64EC) && (defined(__SSE2__) || defined(_M_X64) || (defined(_M_IX86_FP) && _M_IX86_FP >= 2))
-    #include <emmintrin.h>
-    #define JSON_SCAN_SSE2 1
-#else
-    #define JSON_SCAN_SSE2 0
-#endif
-#if JSON_SCAN_SSE2 && defined(__SSSE3__)
-    #include <tmmintrin.h>
-    #define JSON_SCAN_SSSE3 1 // NOLINT(cppcoreguidelines-macro-to-enum,modernize-macro-to-enum)
-#else
-    #define JSON_SCAN_SSSE3 0 // NOLINT(cppcoreguidelines-macro-to-enum,modernize-macro-to-enum)
-#endif
-#if JSON_SCAN_SSE2 && !JSON_SCAN_SSSE3 && !defined(NLOHMANN_JSON_NO_TARGET_ATTRIBUTE) && ((defined(__clang__) && __clang_major__ >= 4) || (defined(__GNUC__) && !defined(__clang__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 9))))
-    // (GCC before 4.9 has no SSSE3 intrinsics without -mssse3)
-    #include <cpuid.h>
-    #include <tmmintrin.h>
-    #define JSON_SCAN_SSSE3_DISPATCH 1 // NOLINT(cppcoreguidelines-macro-to-enum,modernize-macro-to-enum)
-    #define JSON_SCAN_SSSE3_TARGET __attribute__((target("ssse3")))
-#elif JSON_SCAN_SSE2 && !JSON_SCAN_SSSE3 && defined(_MSC_VER)
-    // (MSVC compiles intrinsics of any instruction set)
-    #include <intrin.h>
-    #include <tmmintrin.h>
-    #define JSON_SCAN_SSSE3_DISPATCH 1 // NOLINT(cppcoreguidelines-macro-to-enum,modernize-macro-to-enum)
-    #define JSON_SCAN_SSSE3_TARGET
-#else
-    #define JSON_SCAN_SSSE3_DISPATCH 0 // NOLINT(cppcoreguidelines-macro-to-enum,modernize-macro-to-enum)
-    #define JSON_SCAN_SSSE3_TARGET
-#endif
-#define JSON_SCAN_VECTOR (JSON_SCAN_NEON || JSON_SCAN_SSE2)
-#define JSON_SCAN_VECTOR_UTF8 (JSON_SCAN_NEON || JSON_SCAN_SSSE3 || JSON_SCAN_SSSE3_DISPATCH)
-
-NLOHMANN_JSON_NAMESPACE_BEGIN
-namespace detail
-{
-
-#if JSON_SCAN_VECTOR
-/*!
-@brief the first byte of a string run that is a quote, a backslash, a control
-character, or not ASCII, 16 bytes per step
-
-Stops at such a byte, or where fewer than 16 bytes are left (the caller tells
-the two apart). A signed compare with 0x20 finds control characters and
-non-ASCII bytes at once.
-*/
-JSON_HEDLEY_ALWAYS_INLINE const unsigned char* vector_plain_run(const unsigned char* p, const unsigned char* e) noexcept
-{
-    while (e - p >= 16)
-    {
-#if JSON_SCAN_NEON
-        const uint8x16_t in = vld1q_u8(p);
-        const uint8x16_t special = vorrq_u8(vorrq_u8(vceqq_u8(in, vdupq_n_u8('"')), vceqq_u8(in, vdupq_n_u8('\\'))),
-                                            vcltq_s8(vreinterpretq_s8_u8(in), vdupq_n_s8(0x20)));
-        // one nibble per byte (the usual NEON replacement of x86's movemask, see
-        // D. Kutenin, "Porting x86 vector bitmask optimizations to Arm NEON", 2022)
-        const std::uint64_t bits = vget_lane_u64(vreinterpret_u64_u8(vshrn_n_u16(vreinterpretq_u16_u8(special), 4)), 0);
-        if (bits != 0)
-        {
-            return p + (count_trailing_zeros(bits) >> 2u);
-        }
-#else
-        const __m128i in = _mm_loadu_si128(static_cast<const __m128i*>(static_cast<const void*>(p))); // NOLINT(bugprone-casting-through-void)
-        const __m128i special = _mm_or_si128(_mm_or_si128(_mm_cmpeq_epi8(in, _mm_set1_epi8('"')), _mm_cmpeq_epi8(in, _mm_set1_epi8('\\'))),
-                                             _mm_cmplt_epi8(in, _mm_set1_epi8(0x20)));
-        const auto bits = static_cast<std::uint64_t>(static_cast<unsigned>(_mm_movemask_epi8(special)));
-        if (bits != 0)
-        {
-            return p + count_trailing_zeros(bits);
-        }
-#endif
-        p += 16;
-    }
-    return p;
-}
-#endif
-
-#if JSON_SCAN_VECTOR
-/// vector_plain_run() for runs that are already longer than a few words:
-/// inline with SSE2, out of line with NEON, where a larger string loop slows
-/// down the rest of the lexer
-#if JSON_SCAN_NEON
-    JSON_HEDLEY_NEVER_INLINE inline
-#else
-    JSON_HEDLEY_ALWAYS_INLINE
-#endif
-const unsigned char* vector_plain_run_long(const unsigned char* p, const unsigned char* e) noexcept
-{
-    return vector_plain_run(p, e);
-}
-#endif
-
-#if JSON_SCAN_SSSE3_DISPATCH
-/// whether the CPU has SSSE3 (CPUID leaf 1, ECX bit 9)
-inline bool cpu_ssse3() noexcept
-{
-#if defined(_MSC_VER) && !defined(__clang__)
-    std::array<int, 4> regs {{}};
-    __cpuid(regs.data(), 1);
-    return (static_cast<unsigned>(regs[2]) & (1u << 9u)) != 0;
-#else
-    unsigned eax = 0;
-    unsigned ebx = 0;
-    unsigned ecx = 0;
-    unsigned edx = 0;
-    return __get_cpuid(1, &eax, &ebx, &ecx, &edx) != 0 && (ecx & (1u << 9u)) != 0;
-#endif
-}
-
-/// whether the CPU has SSSE3, asked once: the answer is kept in an atomic
-/// that is initialized at compile time, so that neither a guard of a local
-/// static nor a global constructor is needed (threads that ask at the same
-/// time all store the same answer)
-JSON_HEDLEY_ALWAYS_INLINE bool cpu_has_ssse3() noexcept
-{
-    static std::atomic<int> known{0}; // 0: not asked yet, 1: no, 2: yes
-    int state = known.load(std::memory_order_relaxed);
-    if (JSON_HEDLEY_UNLIKELY(state == 0))
-    {
-        state = cpu_ssse3() ? 2 : 1;
-        known.store(state, std::memory_order_relaxed);
-    }
-    return state == 2;
-}
-#endif
-
-#if JSON_SCAN_VECTOR_UTF8
-/// Tables of the UTF-8 check of J. Keiser and D. Lemire, "Validating UTF-8 In
-/// Less Than One Instruction Per Byte" (2021), as in simdjson ("lookup4"): each
-/// maps a nibble (high and low nibble of the previous byte, high nibble of the
-/// current byte) to the errors it allows; a byte pair is ill-formed if all
-/// three have an error bit in common.
-template<typename Dummy = void>
-struct utf8_lookup4
-{
-    static constexpr std::uint8_t too_short = 1u << 0u, too_long = 1u << 1u, overlong_3 = 1u << 2u, too_large = 1u << 3u;
-    static constexpr std::uint8_t surrogate = 1u << 4u, overlong_2 = 1u << 5u, too_large_1000 = 1u << 6u, overlong_4 = 1u << 6u;
-    static constexpr std::uint8_t two_conts = 1u << 7u, carry = too_short | too_long | two_conts;
-    static const std::array<std::uint8_t, 16> byte_1_high;
-    static const std::array<std::uint8_t, 16> byte_1_low;
-    static const std::array<std::uint8_t, 16> byte_2_high;
-};
-
-template<typename Dummy>
-const std::array<std::uint8_t, 16> utf8_lookup4<Dummy>::byte_1_high =
-{
-    {
-        too_long, too_long, too_long, too_long, too_long, too_long, too_long, too_long,
-        two_conts, two_conts, two_conts, two_conts,
-        too_short | overlong_2, too_short, too_short | overlong_3 | surrogate, too_short | too_large | too_large_1000 | overlong_4
-    }
-};
-
-template<typename Dummy>
-const std::array<std::uint8_t, 16> utf8_lookup4<Dummy>::byte_1_low =
-{
-    {
-        carry | overlong_3 | overlong_2 | overlong_4, carry | overlong_2, carry, carry,
-        carry | too_large, carry | too_large | too_large_1000, carry | too_large | too_large_1000, carry | too_large | too_large_1000,
-        carry | too_large | too_large_1000, carry | too_large | too_large_1000, carry | too_large | too_large_1000, carry | too_large | too_large_1000,
-        carry | too_large | too_large_1000, carry | too_large | too_large_1000 | surrogate, carry | too_large | too_large_1000, carry | too_large | too_large_1000
-    }
-};
-
-template<typename Dummy>
-const std::array<std::uint8_t, 16> utf8_lookup4<Dummy>::byte_2_high =
-{
-    {
-        too_short, too_short, too_short, too_short, too_short, too_short, too_short, too_short,
-        static_cast<std::uint8_t>(too_long | overlong_2 | two_conts | overlong_3 | too_large_1000 | overlong_4),
-        static_cast<std::uint8_t>(too_long | overlong_2 | two_conts | overlong_3 | too_large),
-        static_cast<std::uint8_t>(too_long | overlong_2 | two_conts | surrogate | too_large),
-        static_cast<std::uint8_t>(too_long | overlong_2 | two_conts | surrogate | too_large),
-        too_short, too_short, too_short, too_short
-    }
-};
-
-/*!
-@brief the run of plain string bytes and well-formed UTF-8 at p (a character
-       boundary), 16 bytes per step
-
-The first quote, backslash, or control character is found with vector
-compares, and the UTF-8 check of J. Keiser and D. Lemire covers the bytes up
-to it. Returns true with @a block at that byte; returns false with @a block at
-the start of the 16 bytes where the check found ill-formed UTF-8 or where
-fewer than 16 bytes are left, for the caller to finish one sequence at a time.
-Out of line, so that no constants of the check occupy registers in the
-caller's loop. On x86-64, it is compiled for SSSE3 (see cpu_has_ssse3()).
-*/
-JSON_SCAN_SSSE3_TARGET JSON_HEDLEY_NEVER_INLINE inline bool vector_utf8_run(const unsigned char* p, const unsigned char* e, const unsigned char*& block_out) noexcept
-{
-    using lookup = utf8_lookup4<>;
-    const unsigned char* block = p;
-#if JSON_SCAN_NEON
-    const uint8x16_t t1h = vld1q_u8(lookup::byte_1_high.data());
-    const uint8x16_t t1l = vld1q_u8(lookup::byte_1_low.data());
-    const uint8x16_t t2h = vld1q_u8(lookup::byte_2_high.data());
-    uint8x16_t prev = vdupq_n_u8(0);
-    while (e - block >= 16)
-    {
-        const uint8x16_t in = vld1q_u8(block);
-        const uint8x16_t special = vorrq_u8(vorrq_u8(vceqq_u8(in, vdupq_n_u8('"')), vceqq_u8(in, vdupq_n_u8('\\'))), vcltq_u8(in, vdupq_n_u8(0x20)));
-        const uint8x16_t prev1 = vextq_u8(prev, in, 15);
-        const uint8x16_t sc = vandq_u8(vandq_u8(vqtbl1q_u8(t1h, vshrq_n_u8(prev1, 4)), vqtbl1q_u8(t1l, vandq_u8(prev1, vdupq_n_u8(0x0F)))), vqtbl1q_u8(t2h, vshrq_n_u8(in, 4)));
-        const uint8x16_t must23 = vorrq_u8(vqsubq_u8(vextq_u8(prev, in, 14), vdupq_n_u8(0xE0 - 0x80)), vqsubq_u8(vextq_u8(prev, in, 13), vdupq_n_u8(0xF0 - 0x80)));
-        const uint8x16_t err = veorq_u8(vandq_u8(must23, vdupq_n_u8(0x80)), sc);
-        const std::uint64_t special_bits = vget_lane_u64(vreinterpret_u64_u8(vshrn_n_u16(vreinterpretq_u16_u8(special), 4)), 0);
-        const std::uint64_t err_bits = vget_lane_u64(vreinterpret_u64_u8(vshrn_n_u16(vreinterpretq_u16_u8(vtstq_u8(err, err)), 4)), 0);
-        if (special_bits != 0)
-        {
-            // errors up to the special byte count (an incomplete sequence
-            // before a quote shows at the quote); the bytes after it do not
-            const unsigned k = static_cast<unsigned>(count_trailing_zeros(special_bits)) >> 2u;
-            const std::uint64_t upto = k == 15 ? ~std::uint64_t{0} :
-                                       (std::uint64_t{1} << (4u * (k + 1u))) - 1u;
-            if ((err_bits & upto) == 0)
-            {
-                block_out = block + k;
-                return true;
-            }
-            break;
-        }
-        if (err_bits != 0)
-        {
-            break;
-        }
-        prev = in;
-        block += 16;
-    }
-#else
-    // the same with SSSE3 (pshufb for the table lookups; nibbles from 16-bit
-    // shifts, as there are no byte shifts)
-    const __m128i t1h = _mm_loadu_si128(static_cast<const __m128i*>(static_cast<const void*>(lookup::byte_1_high.data()))); // NOLINT(bugprone-casting-through-void)
-    const __m128i t1l = _mm_loadu_si128(static_cast<const __m128i*>(static_cast<const void*>(lookup::byte_1_low.data()))); // NOLINT(bugprone-casting-through-void)
-    const __m128i t2h = _mm_loadu_si128(static_cast<const __m128i*>(static_cast<const void*>(lookup::byte_2_high.data()))); // NOLINT(bugprone-casting-through-void)
-    const __m128i nibble = _mm_set1_epi8(0x0F);
-    const __m128i zero = _mm_setzero_si128();
-    __m128i prev = zero;
-    while (e - block >= 16)
-    {
-        const __m128i in = _mm_loadu_si128(static_cast<const __m128i*>(static_cast<const void*>(block))); // NOLINT(bugprone-casting-through-void)
-        const __m128i special = _mm_or_si128(_mm_or_si128(_mm_cmpeq_epi8(in, _mm_set1_epi8('"')), _mm_cmpeq_epi8(in, _mm_set1_epi8('\\'))),
-                                             _mm_cmpeq_epi8(_mm_subs_epu8(in, _mm_set1_epi8(0x1F)), zero)); // in < 0x20
-        const __m128i prev1 = _mm_alignr_epi8(in, prev, 15);
-        const __m128i sc = _mm_and_si128(_mm_and_si128(_mm_shuffle_epi8(t1h, _mm_and_si128(_mm_srli_epi16(prev1, 4), nibble)),
-                                         _mm_shuffle_epi8(t1l, _mm_and_si128(prev1, nibble))),
-                                         _mm_shuffle_epi8(t2h, _mm_and_si128(_mm_srli_epi16(in, 4), nibble)));
-        const __m128i must23 = _mm_or_si128(_mm_subs_epu8(_mm_alignr_epi8(in, prev, 14), _mm_set1_epi8(0xE0 - 0x80)),
-                                            _mm_subs_epu8(_mm_alignr_epi8(in, prev, 13), _mm_set1_epi8(0xF0 - 0x80)));
-        const __m128i err = _mm_xor_si128(_mm_and_si128(must23, _mm_set1_epi8(static_cast<char>(-128))), sc);
-        const auto special_bits = static_cast<unsigned>(_mm_movemask_epi8(special));
-        const auto err_bits = ~static_cast<unsigned>(_mm_movemask_epi8(_mm_cmpeq_epi8(err, zero))) & 0xFFFFu;
-        if (special_bits != 0)
-        {
-            const auto k = static_cast<unsigned>(count_trailing_zeros(static_cast<std::uint64_t>(special_bits)));
-            if ((err_bits & ((2u << k) - 1u)) == 0)
-            {
-                block_out = block + k;
-                return true;
-            }
-            break;
-        }
-        if (err_bits != 0)
-        {
-            break;
-        }
-        prev = in;
-        block += 16;
-    }
-#endif
-    block_out = block;
-    return false;
-}
-#endif
-
-}  // namespace detail
-NLOHMANN_JSON_NAMESPACE_END

include/nlohmann/detail/input/string_scan.hpp

@@ -14,7 +14,6 @@
 #include <cstring> // memcpy
 
 #include <nlohmann/detail/bit_ops.hpp>
-#include <nlohmann/detail/input/simd_scan.hpp>
 #include <nlohmann/detail/macro_scope.hpp>
 
 // Optional SIMD backend for bulk UTF-8 validation. This is an opt-in external
@@ -35,7 +34,7 @@
 // This file contains the byte-level string-scanning helpers used by the lexer's
 // contiguous fast path. They operate purely on raw bytes (no dependency on the
 // lexer's template parameters) so they are free functions, keeping the lexer
-// itself focused on the state machine; see lexer::get_after_string_run().
+// itself focused on the state machine; see lexer::scan_string_bulk().
 
 NLOHMANN_JSON_NAMESPACE_BEGIN
 namespace detail
@@ -67,7 +66,7 @@ inline std::uint64_t swar_string_special(std::uint64_t v) noexcept
 
 // return the index of the first is_string_special() byte in [data, data+n), or
 // n if every byte is ordinary; scans 8 bytes at a time
-JSON_HEDLEY_ALWAYS_INLINE std::size_t find_string_special(const unsigned char* data, std::size_t n) noexcept
+inline std::size_t find_string_special(const unsigned char* data, std::size_t n) noexcept
 {
     std::size_t i = 0;
     for (; i + 8 <= n; i += 8)
@@ -236,143 +235,35 @@ inline std::size_t valid_utf8_prefix(const unsigned char* data, std::size_t n) n
     return pos;
 }
 
-#if JSON_SCAN_VECTOR_UTF8
-/// the end of scan_string_vector from block, where the vector loop stopped
-/// (ill-formed UTF-8, or fewer than 16 bytes left): one byte or sequence at a
-/// time, from the start of a sequence that crosses into the block
-inline const unsigned char* scan_string_finish(const unsigned char* p, const unsigned char* block, const unsigned char* e) noexcept
-{
-    for (int i = 1; i <= 3 && block - i >= p; ++i)
-    {
-        const unsigned char c = block[-i];
-        if (c < 0x80)
-        {
-            break;
-        }
-        if (c >= 0xC0)
-        {
-            const int len = 2 + static_cast<int>(c >= 0xE0) + static_cast<int>(c >= 0xF0);
-            if (len > i)
-            {
-                block -= i;
-            }
-            break;
-        }
-    }
-    for (p = block; p != e;)
-    {
-        if (*p < 0x80)
-        {
-            if (is_string_special(*p))
-            {
-                return p;
-            }
-            ++p;
-            continue;
-        }
-        const std::size_t n = validate_one_utf8(p, static_cast<std::size_t>(e - p));
-        if (n == 0)
-        {
-            return p;
-        }
-        p += n;
-    }
-    return p;
-}
-
-/// the rest of a string from p (a character boundary), with the vector UTF-8
-/// check and the scalar check for the end of the block where it stopped
-inline const unsigned char* scan_string_vector(const unsigned char* p, const unsigned char* e) noexcept
-{
-    const unsigned char* block = p;
-    if (vector_utf8_run(p, e, block))
-    {
-        return block;
-    }
-    return scan_string_finish(p, block, e);
-}
-#endif
-
-#if JSON_SCAN_VECTOR
-/// the end of the run of plain string characters at @a p: the first quote,
-/// backslash, control character, or non-ASCII byte, or @a e. The first words
-/// are checked with SWAR (one; four with NEON, where the vector mask costs
-/// more), as most keys and short values end there; longer runs continue 16
-/// bytes at a time.
-JSON_HEDLEY_ALWAYS_INLINE const unsigned char* plain_run_end(const unsigned char* p, const unsigned char* e) noexcept
-{
-    constexpr int prefix_words = JSON_SCAN_NEON ? 4 : 1;
-    for (int words = prefix_words; words > 0 && e - p >= 8; --words)
-    {
-        const std::uint64_t special = swar_string_special(read_eight_bytes(p));
-        if (special != 0)
-        {
-            return p + (static_cast<std::size_t>(count_trailing_zeros(special)) / 8);
-        }
-        p += 8;
-    }
-    // the vector loop only for 16 bytes or more: the serializer passes a
-    // string without its closing quote, so most of its runs end at e, and a
-    // call of the out-of-line NEON loop for a shorter rest made dump() up to
-    // 10% slower
-    if (e - p >= 16)
-    {
-        p = vector_plain_run_long(p, e);
-        if (e - p >= 16)
-        {
-            return p; // the vector loop stopped at a special byte
-        }
-    }
-    return p + find_string_special(p, static_cast<std::size_t>(e - p));
-}
-#endif
-
-// Computation of the bulk run length: the number of leading bytes in
-// [data, data+n) that are ordinary ASCII or complete well-formed UTF-8
+// Scalar (C++11) computation of the bulk run length: the number of leading
+// bytes in [data, data+n) that are ordinary ASCII or complete well-formed UTF-8
 // sequences, stopping before the first byte that needs individual handling (the
 // closing quote, an escape, a control character, or an ill-formed/truncated
-// sequence). ASCII is skipped 16 bytes at a time with SSE2 and 8 bytes at a
-// time otherwise; runs of non-ASCII text use the vector UTF-8 check where
-// available.
-JSON_HEDLEY_ALWAYS_INLINE std::size_t scalar_string_bulk_run(const unsigned char* data, std::size_t n) noexcept
+// sequence). ASCII is skipped 8 bytes at a time.
+inline std::size_t scalar_string_bulk_run(const unsigned char* data, std::size_t n) noexcept
 {
-    const unsigned char* const e = data + n;
-    const unsigned char* p = data;
-    while (p != e)
+    std::size_t pos = 0;
+    while (pos < n)
     {
-#if JSON_SCAN_VECTOR
-        p = plain_run_end(p, e);
-#else
-        p += find_string_special(p, static_cast<std::size_t>(e - p));
-#endif
-        if (p == e || *p < 0x80u)
+        pos += find_string_special(data + pos, n - pos);
+        if (pos >= n || data[pos] < 0x80u)
         {
             break; // end of buffer, or a quote/escape/control byte
         }
-#if JSON_SCAN_VECTOR_UTF8
-#if JSON_SCAN_SSSE3_DISPATCH
-        if (JSON_HEDLEY_LIKELY(cpu_has_ssse3()))
-#endif
-        {
-            return static_cast<std::size_t>(scan_string_vector(p, e) - data);
-        }
-#endif
-#if !JSON_SCAN_VECTOR_UTF8 || JSON_SCAN_SSSE3_DISPATCH
         // a run of multi-byte sequences (e.g. CJK text) is validated sequence
         // by sequence without searching for the next special byte in between
         do
         {
-            const std::size_t seq = validate_one_utf8(p, static_cast<std::size_t>(e - p));
+            const std::size_t seq = validate_one_utf8(data + pos, n - pos);
             if (seq == 0)
             {
-                return static_cast<std::size_t>(p - data); // ill-formed or truncated: let the byte path diagnose it
+                return pos; // ill-formed or truncated: let the byte path diagnose it
             }
-            p += seq;
+            pos += seq;
         }
-        while (p != e && *p >= 0x80u);
-#endif
+        while (pos < n && data[pos] >= 0x80u);
     }
-    return static_cast<std::size_t>(p - data);
+    return pos;
 }
 
 #if defined(JSON_USE_SIMDUTF) && defined(JSON_HAS_CPP_17)
@@ -413,7 +304,7 @@ inline std::size_t find_string_delimiter(const unsigned char* data, std::size_t
 // next delimiter is validated in one shot by simdutf; on the rare failure the
 // scalar helper recomputes the exact valid prefix so the byte path still
 // produces the precise diagnostic. Without it, the pure scalar path is used.
-JSON_HEDLEY_ALWAYS_INLINE std::size_t string_bulk_run(const unsigned char* data, std::size_t n) noexcept
+inline std::size_t string_bulk_run(const unsigned char* data, std::size_t n) noexcept
 {
 #if defined(JSON_USE_SIMDUTF) && defined(JSON_HAS_CPP_17)
     const std::size_t run = find_string_delimiter(data, n);
@@ -425,42 +316,6 @@ JSON_HEDLEY_ALWAYS_INLINE std::size_t string_bulk_run(const unsigned char* data,
     return scalar_string_bulk_run(data, n);
 }
 
-#if JSON_SCAN_NEON
-/// scalar_string_bulk_run() from @a start on, out of line (see
-/// lexer_string_bulk_run())
-JSON_HEDLEY_NEVER_INLINE inline std::size_t string_bulk_run_from(const unsigned char* data, std::size_t start, std::size_t n) noexcept
-{
-    return start + scalar_string_bulk_run(data + start, n - start);
-}
-#endif
-
-// string_bulk_run() for the lexer. With NEON, only the first four words are
-// checked inline (most keys and short values end there), and longer runs and
-// non-ASCII text continue out of line. The lexer's scan function runs once per
-// token, and the vector code inlined into it needs more registers, which every
-// token pays for: 5% of json::accept() on jeopardy.json with Apple Clang on
-// Apple M1, even though no string of that file reaches the vector code. The
-// serializer keeps string_bulk_run() inline, which is faster there.
-JSON_HEDLEY_ALWAYS_INLINE std::size_t lexer_string_bulk_run(const unsigned char* data, std::size_t n) noexcept
-{
-#if JSON_SCAN_NEON && !(defined(JSON_USE_SIMDUTF) && defined(JSON_HAS_CPP_17))
-    std::size_t i = 0;
-    for (int words = 4; words > 0 && n - i >= 8; --words)
-    {
-        const std::uint64_t special = swar_string_special(read_eight_bytes(data + i));
-        if (special != 0)
-        {
-            const std::size_t pos = i + (static_cast<std::size_t>(count_trailing_zeros(special)) / 8);
-            return data[pos] < 0x80u ? pos : string_bulk_run_from(data, pos, n);
-        }
-        i += 8;
-    }
-    return string_bulk_run_from(data, i, n);
-#else
-    return string_bulk_run(data, n);
-#endif
-}
-
 // Decode the 4 hex digits at [data, data+4) - the digits following a `\u`
 // escape - into a codepoint 0x0000..0xFFFF via one table lookup per byte
 // (after yyjson's read_hex_u16), or return -1 if any of the 4 bytes is not a

include/nlohmann/detail/iterators/iter_impl.hpp

@@ -680,12 +680,12 @@ class iter_impl // NOLINT(cppcoreguidelines-special-member-functions,hicpp-speci
     {
         JSON_ASSERT(m_object != nullptr);
 
-        if (JSON_HEDLEY_LIKELY(m_object->is_object()))
+        if (JSON_HEDLEY_UNLIKELY(!m_object->is_object()))
         {
-            return m_it.object_iterator->first;
+            throw_literal<invalid_iterator>(exception_id::iterator_key_not_object, "cannot use key() for non-object iterators", m_object);
         }
 
-        throw_literal<invalid_iterator>(exception_id::iterator_key_not_object, "cannot use key() for non-object iterators", m_object);
+        return m_it.object_iterator->first;
     }
 
     /*!

include/nlohmann/detail/json_pointer.hpp

@@ -11,6 +11,7 @@
 #include <algorithm> // all_of
 #include <cctype> // isdigit
 #include <cerrno> // errno, ERANGE
+#include <cstddef> // size_t
 #include <cstdlib> // strtoull
 #ifndef JSON_NO_IO
     #include <iosfwd> // ostream
@@ -334,7 +335,7 @@ class json_pointer
                 {
                     break; // not a plain number: let strtoull decide
                 }
-                acc = static_cast<size_type>(acc * 10 + static_cast<size_type>(c - '0'));
+                acc = static_cast<size_type>((acc * 10) + static_cast<size_type>(c - '0'));
                 if (JSON_HEDLEY_UNLIKELY(i == s.size() - 1))
                 {
                     idx = acc;
@@ -529,10 +530,10 @@ class json_pointer
 
         static std::size_t hash_of(std::size_t parent, const string_t& token) noexcept
         {
-            std::size_t h = parent * static_cast<std::size_t>(0x9E3779B97F4A7C15ULL);
+            std::size_t h = parent * static_cast<std::size_t>(0x9E3779B97F4A7C15ULL & (std::numeric_limits<std::size_t>::max)());
             for (std::size_t i = 0; i < token.size(); ++i)
             {
-                h = (h ^ static_cast<unsigned char>(token[i])) * static_cast<std::size_t>(0x100000001B3ULL);
+                h = (h ^ static_cast<unsigned char>(token[i])) * static_cast<std::size_t>(0x100000001B3ULL & (std::numeric_limits<std::size_t>::max)());
             }
             return h ^ (h >> 29u);
         }

include/nlohmann/detail/macro_scope.hpp

@@ -895,11 +895,3 @@
 #ifndef JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
     #define JSON_DISABLE_TUPLE_REFERENCE_CONVERSION 0
 #endif
-
-#ifndef JSON_DISABLE_STREAM_BULK_SCAN
-    #define JSON_DISABLE_STREAM_BULK_SCAN 0
-#endif
-
-#ifndef JSON_DISABLE_UNLOCKED_FILE_IO
-    #define JSON_DISABLE_UNLOCKED_FILE_IO 0
-#endif

include/nlohmann/detail/macro_unscope.hpp

@@ -21,18 +21,9 @@
 #undef JSON_NO_UNIQUE_ADDRESS
 #undef JSON_DISABLE_ENUM_SERIALIZATION
 #undef JSON_DISABLE_TUPLE_REFERENCE_CONVERSION
-#undef JSON_DISABLE_STREAM_BULK_SCAN
-#undef JSON_DISABLE_UNLOCKED_FILE_IO
 #undef JSON_UNLOCKED_FILE_IO
 #undef JSON_DTOA_SSE2
 #undef JSON_DTOA_NEON
-#undef JSON_SCAN_NEON
-#undef JSON_SCAN_SSE2
-#undef JSON_SCAN_SSSE3
-#undef JSON_SCAN_SSSE3_DISPATCH
-#undef JSON_SCAN_SSSE3_TARGET
-#undef JSON_SCAN_VECTOR
-#undef JSON_SCAN_VECTOR_UTF8
 
 #ifndef JSON_TEST_KEEP_MACROS
     #undef JSON_CATCH
@@ -57,6 +48,8 @@
     #undef JSON_STRICT_BINARY_UTF8
     #undef JSON_DELETE_DEPRECATED_FUNCTIONS
     #undef JSON_USE_OBJECTS_FOR_ENUM_KEYED_MAPS
+    #undef JSON_DISABLE_STREAM_BULK_SCAN
+    #undef JSON_DISABLE_UNLOCKED_FILE_IO
 #endif
 
 #include <nlohmann/thirdparty/hedley/hedley_undef.hpp>

include/nlohmann/json.hpp

@@ -29,6 +29,7 @@
 #endif  // JSON_NO_IO
 #include <iterator> // make_move_iterator, random_access_iterator_tag
 #include <limits> // numeric_limits
+#include <map> // map
 #include <memory> // unique_ptr
 #include <set> // swap, operator!=
 #include <stdexcept> // length_error
@@ -754,26 +755,20 @@ private:
         // one level deep); stops at the first structured child it meets
         static bool all_children_leaves(const basic_json& v) noexcept
         {
+            // array_t only needs forward iterators (see custom_array_type)
             if (v.m_data.m_type == value_t::array)
             {
                 const auto& a = *v.m_data.m_value.array;
-                for (auto it = a.rbegin(); it != a.rend(); ++it)
+                return std::all_of(a.begin(), a.end(), [](const basic_json & el)
                 {
-                    if (!has_no_children(*it))
-                    {
-                        return false;
-                    }
-                }
-                return true;
+                    return has_no_children(el);
+                });
             }
-            for (const auto& el : *v.m_data.m_value.object)
+            const auto& o = *v.m_data.m_value.object;
+            return std::all_of(o.begin(), o.end(), [](const typename object_t::value_type & el)
             {
-                if (!has_no_children(el.second))
-                {
-                    return false;
-                }
-            }
-            return true;
+                return has_no_children(el.second);
+            });
         }
 
         // The walk in destroy_container() may take the children of a
@@ -1230,7 +1225,7 @@ public:
     }
 
     template < typename O = object_t, detail::enable_if_t < detail::has_stable_elements<O>::value, int > = 0 >
-    static constexpr std::size_t object_capacity() noexcept
+    std::size_t object_capacity() const noexcept
     {
         return 0;
     }
@@ -1242,7 +1237,7 @@ public:
     }
 
     template < typename O = object_t, detail::enable_if_t < !detail::has_stable_elements<O>::value && !detail::is_nlohmann_ordered_map<O>::value, int > = 0 >
-    static constexpr std::size_t object_capacity() noexcept
+    std::size_t object_capacity() const noexcept
     {
         return detail::unknown_size();
     }
@@ -3043,18 +3038,21 @@ public:
     JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE
     static void throw_iterator_range_of_null(const basic_json* obj)
     {
+        static_cast<void>(obj); // unused when JSON_NOEXCEPTION is defined
         JSON_THROW(invalid_iterator::create(detail::exception_id::iterator_range_of_null, detail::concat("cannot construct with iterators from ", obj->type_name()), obj));
     }
 
     JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE
     static void throw_incompatible_reference_type(const basic_json& obj)
     {
+        static_cast<void>(obj); // unused when JSON_NOEXCEPTION is defined
         JSON_THROW(type_error::create(detail::exception_id::incompatible_reference_type, detail::concat("incompatible ReferenceType for get_ref, actual type is ", obj.type_name()), &obj));
     }
 
     JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE
     static void throw_array_index_exceeds_size_type(size_type idx)
     {
+        static_cast<void>(idx); // unused when JSON_NOEXCEPTION is defined
         JSON_THROW(std::length_error(detail::concat("array index ", std::to_string(idx), " exceeds size_type")));
     }
 
@@ -3062,6 +3060,8 @@ public:
     JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE
     static void throw_array_index_out_of_range(size_type idx, const basic_json& j)
     {
+        static_cast<void>(idx); // unused when JSON_NOEXCEPTION is defined
+        static_cast<void>(j);
         JSON_THROW(out_of_range::create(detail::exception_id::array_index_out_of_range, detail::concat("array index ", std::to_string(idx), " is out of range"), &j));
     }
 
@@ -3070,6 +3070,8 @@ public:
     JSON_HEDLEY_NO_RETURN JSON_HEDLEY_NEVER_INLINE
     static void throw_key_not_found(const KeyType& key, const basic_json& j)
     {
+        static_cast<void>(key); // unused when JSON_NOEXCEPTION is defined
+        static_cast<void>(j);
         JSON_THROW(out_of_range::create(detail::exception_id::key_not_found, detail::concat("key '", key, "' not found"), &j));
     }
 
@@ -4893,19 +4895,19 @@ public:
     iterator insert(const_iterator pos, const basic_json& val) // NOLINT(performance-unnecessary-value-param)
     {
         // insert only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
+        if (JSON_HEDLEY_UNLIKELY(!is_array()))
         {
-            // check if iterator pos fits to this JSON value
-            if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-            {
-                detail::throw_literal<invalid_iterator>(detail::exception_id::iterator_from_other_value, "iterator does not fit current value", this);
-            }
-
-            // insert to array and return iterator
-            return insert_iterator(pos, val);
+            detail::throw_cannot_use_with(detail::exception_id::insert_wrong_type, "insert()", *this);
         }
 
-        detail::throw_cannot_use_with(detail::exception_id::insert_wrong_type, "insert()", *this);
+        // check if iterator pos fits to this JSON value
+        if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
+        {
+            detail::throw_literal<invalid_iterator>(detail::exception_id::iterator_from_other_value, "iterator does not fit current value", this);
+        }
+
+        // insert to array and return iterator
+        return insert_iterator(pos, val);
     }
 
     /// @brief inserts element into array
@@ -4913,21 +4915,21 @@ public:
     iterator insert(const_iterator pos, basic_json&& val) // NOLINT(performance-unnecessary-value-param)
     {
         // insert only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
+        if (JSON_HEDLEY_UNLIKELY(!is_array()))
         {
-            // check if iterator pos fits to this JSON value
-            if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-            {
-                detail::throw_literal<invalid_iterator>(detail::exception_id::iterator_from_other_value, "iterator does not fit current value", this);
-            }
-
-            // moving into a local first keeps this safe even if val aliases
-            // an element of this array
-            basic_json tmp(std::move(val));
-            return insert_iterator(pos, std::move(tmp));
+            detail::throw_cannot_use_with(detail::exception_id::insert_wrong_type, "insert()", *this);
         }
 
-        detail::throw_cannot_use_with(detail::exception_id::insert_wrong_type, "insert()", *this);
+        // check if iterator pos fits to this JSON value
+        if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
+        {
+            detail::throw_literal<invalid_iterator>(detail::exception_id::iterator_from_other_value, "iterator does not fit current value", this);
+        }
+
+        // moving into a local first keeps this safe even if val aliases
+        // an element of this array
+        basic_json tmp(std::move(val));
+        return insert_iterator(pos, std::move(tmp));
     }
 
     /// @brief inserts copies of element into array
@@ -4935,19 +4937,19 @@ public:
     iterator insert(const_iterator pos, size_type cnt, const basic_json& val) // NOLINT(performance-unnecessary-value-param)
     {
         // insert only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
+        if (JSON_HEDLEY_UNLIKELY(!is_array()))
         {
-            // check if iterator pos fits to this JSON value
-            if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-            {
-                detail::throw_literal<invalid_iterator>(detail::exception_id::iterator_from_other_value, "iterator does not fit current value", this);
-            }
-
-            // insert to array and return iterator
-            return insert_iterator(pos, cnt, val);
+            detail::throw_cannot_use_with(detail::exception_id::insert_wrong_type, "insert()", *this);
         }
 
-        detail::throw_cannot_use_with(detail::exception_id::insert_wrong_type, "insert()", *this);
+        // check if iterator pos fits to this JSON value
+        if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
+        {
+            detail::throw_literal<invalid_iterator>(detail::exception_id::iterator_from_other_value, "iterator does not fit current value", this);
+        }
+
+        // insert to array and return iterator
+        return insert_iterator(pos, cnt, val);
     }
 
     /// @brief inserts range of elements into array
@@ -5453,7 +5455,7 @@ public:
     // inline fast path for two values of the same non-owning scalar type; anything
     // else falls through to the out-of-line general comparison
 #define JSON_IMPLEMENT_SCALAR_FAST(op, null_result)                                                      \
-    if (lhs.m_data.m_type == rhs.m_data.m_type)                                                          \
+    if (lhs.m_data.m_type == rhs.m_data.m_type) /* NOLINT(readability/braces) */                         \
     {                                                                                                    \
         switch (lhs.m_data.m_type)                                                                       \
         {                                                                                                \

include/nlohmann/ordered_map.hpp

@@ -23,6 +23,7 @@
 #include <nlohmann/detail/abi_macros.hpp>
 #include <nlohmann/detail/macro_scope.hpp>
 #include <nlohmann/detail/meta/type_traits.hpp>
+#include <nlohmann/thirdparty/hedley/hedley.hpp>
 
 NLOHMANN_JSON_NAMESPACE_BEGIN
 

single_include/nlohmann/json_fwd.hpp

@@ -71,6 +71,14 @@
     #define JSON_USE_OBJECTS_FOR_ENUM_KEYED_MAPS 0
 #endif
 
+#ifndef JSON_DISABLE_STREAM_BULK_SCAN
+    #define JSON_DISABLE_STREAM_BULK_SCAN 0
+#endif
+
+#ifndef JSON_DISABLE_UNLOCKED_FILE_IO
+    #define JSON_DISABLE_UNLOCKED_FILE_IO 0
+#endif
+
 #if JSON_DIAGNOSTICS
     #define NLOHMANN_JSON_ABI_TAG_DIAGNOSTICS _diag
 #else
@@ -119,14 +127,26 @@
     #define NLOHMANN_JSON_ABI_TAG_OBJECTS_FOR_ENUM_KEYED_MAPS
 #endif
 
+#if JSON_DISABLE_STREAM_BULK_SCAN
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_STREAM_BULK_SCAN _dsbs
+#else
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_STREAM_BULK_SCAN
+#endif
+
+#if JSON_DISABLE_UNLOCKED_FILE_IO
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_UNLOCKED_FILE_IO _dufio
+#else
+    #define NLOHMANN_JSON_ABI_TAG_DISABLE_UNLOCKED_FILE_IO
+#endif
+
 #ifndef NLOHMANN_JSON_NAMESPACE_NO_VERSION
     #define NLOHMANN_JSON_NAMESPACE_NO_VERSION 0
 #endif
 
 // Construct the namespace ABI tags component
-#define NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h) json_abi ## a ## b ## c ## d ## e ## f ## g ## h
-#define NLOHMANN_JSON_ABI_TAGS_CONCAT(a, b, c, d, e, f, g, h) \
-    NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h)
+#define NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h, i, j) json_abi ## a ## b ## c ## d ## e ## f ## g ## h ## i ## j
+#define NLOHMANN_JSON_ABI_TAGS_CONCAT(a, b, c, d, e, f, g, h, i, j) \
+    NLOHMANN_JSON_ABI_TAGS_CONCAT_EX(a, b, c, d, e, f, g, h, i, j)
 
 #define NLOHMANN_JSON_ABI_TAGS                                       \
     NLOHMANN_JSON_ABI_TAGS_CONCAT(                                   \
@@ -137,7 +157,9 @@
             NLOHMANN_JSON_ABI_TAG_PRECISE_STREAM_POSITION,           \
             NLOHMANN_JSON_ABI_TAG_STRICT_NUL_HANDLING,               \
             NLOHMANN_JSON_ABI_TAG_STRICT_BINARY_UTF8,                \
-            NLOHMANN_JSON_ABI_TAG_OBJECTS_FOR_ENUM_KEYED_MAPS)
+            NLOHMANN_JSON_ABI_TAG_OBJECTS_FOR_ENUM_KEYED_MAPS,       \
+            NLOHMANN_JSON_ABI_TAG_DISABLE_STREAM_BULK_SCAN,          \
+            NLOHMANN_JSON_ABI_TAG_DISABLE_UNLOCKED_FILE_IO)
 
 // Construct the namespace version component
 #define NLOHMANN_JSON_NAMESPACE_VERSION_CONCAT_EX(major, minor, patch) \

tests/CMakeLists.txt

@@ -118,7 +118,7 @@ endif()
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
     # avoid stack overflow, see https://github.com/nlohmann/json/issues/2955
-    json_test_set_test_options("test-bon8;test-cbor;test-msgpack;test-ubjson;test-bjdata;test-binary_formats" LINK_OPTIONS /STACK:4000000)
+    json_test_set_test_options("test-bon8;test-cbor;test-msgpack;test-ubjson;test-bjdata;test-bjdata_round_trip_draft2;test-bjdata_round_trip_draft3;test-binary_formats" LINK_OPTIONS /STACK:4000000)
 endif()
 
 # disable exceptions for test-disabled_exceptions
@@ -373,25 +373,6 @@ json_test_add_test_for(src/unit-diagnostic-positions.cpp
     MAIN test_main CXX_STANDARDS ${test_cxx_standards} ${test_force}
 )
 
-# the lexer again with the portable string scanning instead of SSE2/NEON, and on
-# x86-64 with SSSE3 compiled in (no check of the CPU)
-json_test_set_test_options(test-class_lexer_no_simd
-    COMPILE_DEFINITIONS JSON_NO_SIMD
-)
-json_test_add_test_for(src/unit-class_lexer.cpp
-    NAME test-class_lexer_no_simd
-    MAIN test_main CXX_STANDARDS ${test_cxx_standards} ${test_force}
-)
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^(x86_64|AMD64|amd64)$" AND NOT MSVC)
-    json_test_set_test_options(test-class_lexer_ssse3
-        COMPILE_OPTIONS -mssse3
-    )
-    json_test_add_test_for(src/unit-class_lexer.cpp
-        NAME test-class_lexer_ssse3
-        MAIN test_main CXX_STANDARDS ${test_cxx_standards} ${test_force}
-    )
-endif()
-
 # test reading from a std::istream again without scanning the get area in bulk
 json_test_set_test_options(test-stream-bulk-scan_disabled
     COMPILE_DEFINITIONS JSON_DISABLE_STREAM_BULK_SCAN=1

tests/abi/config/CMakeLists.txt

@@ -21,7 +21,9 @@ foreach(test default noversion)
     target_compile_definitions(abi_config_${test}_all_tags PRIVATE
         JSON_DIAGNOSTICS=1
         JSON_DIAGNOSTIC_POSITIONS=1
-        JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON=1)
+        JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON=1
+        JSON_DISABLE_STREAM_BULK_SCAN=1
+        JSON_DISABLE_UNLOCKED_FILE_IO=1)
     target_link_libraries(abi_config_${test}_all_tags PRIVATE abi_compat_main)
     add_test(
         NAME test-abi_config_${test}_all_tags

tests/abi/config/default.cpp

@@ -52,6 +52,14 @@ TEST_CASE("default namespace")
         expected += "_ekmo";
 #endif
 
+#if JSON_DISABLE_STREAM_BULK_SCAN
+        expected += "_dsbs";
+#endif
+
+#if JSON_DISABLE_UNLOCKED_FILE_IO
+        expected += "_dufio";
+#endif
+
         expected += "_v" STRINGIZE(NLOHMANN_JSON_VERSION_MAJOR);
         expected += "_" STRINGIZE(NLOHMANN_JSON_VERSION_MINOR);
         expected += "_" STRINGIZE(NLOHMANN_JSON_VERSION_PATCH) "::basic_json";

tests/abi/config/noversion.cpp

@@ -53,6 +53,14 @@ TEST_CASE("default namespace without version component")
         expected += "_ekmo";
 #endif
 
+#if JSON_DISABLE_STREAM_BULK_SCAN
+        expected += "_dsbs";
+#endif
+
+#if JSON_DISABLE_UNLOCKED_FILE_IO
+        expected += "_dufio";
+#endif
+
         expected += "::basic_json";
 
         // fallback for Clang

tests/src/bjdata_round_trip.hpp

@@ -0,0 +1,103 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  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
+
+#pragma once
+
+#include <cstdint> // uint8_t
+#include <vector> // vector
+
+#include "doctest_compatibility.h"
+
+#include <nlohmann/json.hpp>
+
+#include "round_trip_corpus.hpp"
+
+// The BJData round-trip invariants, split by the BJData version that turns a
+// corpus value into j1 (unit-bjdata_round_trip_draft2.cpp and
+// unit-bjdata_round_trip_draft3.cpp). They were part of unit-bjdata.cpp, but
+// took 80 % of its time; as separate tests, both halves run in parallel and
+// stay below the ctest timeout under Valgrind.
+namespace utils
+{
+
+// This checks what the parse_bjdata_fuzzer driver checks (see
+// tests/src/fuzzer-parse_bjdata.cpp), so that a regression shows up in CI
+// rather than as an OSS-Fuzz report: every value from_bjdata() returns
+// (j1) can be serialized with any combination of options, the result can
+// be parsed back (j2), and serializing j2 again with the same options
+// yields a value-equal result.
+//
+// Beyond the driver, this also checks that j2 equals j1 and that
+// serializing j2 reproduces the exact bytes, both except for values that
+// contain a binary value: a binary value is only written as a binary
+// value with Draft 3's optimized binary array, and otherwise read back as
+// an array of integers, for which the writer may choose different (but
+// equally valid) type markers when it is serialized again (see #5494).
+//
+// Values are compared with dump() rather than operator==, because a NaN
+// never compares equal to itself.
+//
+// Only the corpus values written with @a initial_version become j1; each j1
+// is then serialized with every combination of options, both versions
+// included.
+inline void check_bjdata_round_trip(const nlohmann::json::bjdata_version_t initial_version)
+{
+    using nlohmann::json;
+
+    struct options
+    {
+        bool use_size;
+        bool use_type;
+        json::bjdata_version_t version;
+    };
+    const std::vector<options> all_options =
+    {
+        {false, false, json::bjdata_version_t::draft2},
+        {true, false, json::bjdata_version_t::draft2},
+        {true, true, json::bjdata_version_t::draft2},
+        {false, false, json::bjdata_version_t::draft3},
+        {true, false, json::bjdata_version_t::draft3},
+        {true, true, json::bjdata_version_t::draft3},
+    };
+
+    for (const auto& j0 : utils::round_trip_corpus::values())
+    {
+        // turn the corpus value into a value as from_bjdata() returns it
+        for (const auto& initial : all_options)
+        {
+            if (initial.version != initial_version)
+            {
+                continue;
+            }
+
+            const json j1 = json::from_bjdata(json::to_bjdata(j0, initial.use_size, initial.use_type, initial.version));
+            const bool has_binary = utils::round_trip_corpus::contains_binary(j1);
+
+            for (const auto& o : all_options)
+            {
+                INFO("j1 = " << j1.dump() << ", use_size = " << o.use_size << ", use_type = " << o.use_type
+                     << ", draft3 = " << (o.version == json::bjdata_version_t::draft3));
+
+                const std::vector<std::uint8_t> vec = json::to_bjdata(j1, o.use_size, o.use_type, o.version);
+                json j2;
+                // anything the library writes must be parsable by the library
+                REQUIRE_NOTHROW(j2 = json::from_bjdata(vec));
+                const std::vector<std::uint8_t> vec2 = json::to_bjdata(j2, o.use_size, o.use_type, o.version);
+                CHECK(json::from_bjdata(vec2).dump() == j2.dump());
+
+                if (!has_binary)
+                {
+                    CHECK(j2.dump() == j1.dump());
+                    CHECK(vec2 == vec);
+                }
+            }
+        }
+    }
+}
+
+} // namespace utils

tests/src/unit-bjdata.cpp

@@ -28,7 +28,6 @@ using ordered_json = nlohmann::ordered_json;
 #include <fstream>
 #include <set>
 #include "make_test_data_available.hpp"
-#include "round_trip_corpus.hpp"
 #include "test_utils.hpp"
 #include "sax_countdown.hpp"
 using utils::SaxCountdown;
@@ -4441,70 +4440,6 @@ TEST_CASE("BJData use_type requires use_size")
     }
 }
 
-TEST_CASE("BJData round-trip invariants")
-{
-    // This checks what the parse_bjdata_fuzzer driver checks (see
-    // tests/src/fuzzer-parse_bjdata.cpp), so that a regression shows up in CI
-    // rather than as an OSS-Fuzz report: every value from_bjdata() returns
-    // (j1) can be serialized with any combination of options, the result can
-    // be parsed back (j2), and serializing j2 again with the same options
-    // yields a value-equal result.
-    //
-    // Beyond the driver, this also checks that j2 equals j1 and that
-    // serializing j2 reproduces the exact bytes, both except for values that
-    // contain a binary value: a binary value is only written as a binary
-    // value with Draft 3's optimized binary array, and otherwise read back as
-    // an array of integers, for which the writer may choose different (but
-    // equally valid) type markers when it is serialized again (see #5494).
-    //
-    // Values are compared with dump() rather than operator==, because a NaN
-    // never compares equal to itself.
-    struct options
-    {
-        bool use_size;
-        bool use_type;
-        json::bjdata_version_t version;
-    };
-    const std::vector<options> all_options =
-    {
-        {false, false, json::bjdata_version_t::draft2},
-        {true, false, json::bjdata_version_t::draft2},
-        {true, true, json::bjdata_version_t::draft2},
-        {false, false, json::bjdata_version_t::draft3},
-        {true, false, json::bjdata_version_t::draft3},
-        {true, true, json::bjdata_version_t::draft3},
-    };
-
-    for (const auto& j0 : utils::round_trip_corpus::values())
-    {
-        // turn the corpus value into a value as from_bjdata() returns it
-        for (const auto& initial : all_options)
-        {
-            const json j1 = json::from_bjdata(json::to_bjdata(j0, initial.use_size, initial.use_type, initial.version));
-            const bool has_binary = utils::round_trip_corpus::contains_binary(j1);
-
-            for (const auto& o : all_options)
-            {
-                INFO("j1 = " << j1.dump() << ", use_size = " << o.use_size << ", use_type = " << o.use_type
-                     << ", draft3 = " << (o.version == json::bjdata_version_t::draft3));
-
-                const std::vector<std::uint8_t> vec = json::to_bjdata(j1, o.use_size, o.use_type, o.version);
-                json j2;
-                // anything the library writes must be parsable by the library
-                REQUIRE_NOTHROW(j2 = json::from_bjdata(vec));
-                const std::vector<std::uint8_t> vec2 = json::to_bjdata(j2, o.use_size, o.use_type, o.version);
-                CHECK(json::from_bjdata(vec2).dump() == j2.dump());
-
-                if (!has_binary)
-                {
-                    CHECK(j2.dump() == j1.dump());
-                    CHECK(vec2 == vec);
-                }
-            }
-        }
-    }
-}
-
 TEST_CASE("BJData round trip of a binary value is value-stable, not byte-stable")
 {
     // OSS-Fuzz issue 474480402: a Draft 3 optimized binary array is read as a

tests/src/unit-bjdata_round_trip_draft2.cpp

@@ -0,0 +1,22 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  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"
+
+#include <nlohmann/json.hpp>
+using nlohmann::json;
+
+#include "bjdata_round_trip.hpp"
+
+// split from unit-bjdata.cpp, see bjdata_round_trip.hpp; the other half is in
+// unit-bjdata_round_trip_draft3.cpp
+
+TEST_CASE("BJData round-trip invariants (j1 written with Draft 2)")
+{
+    utils::check_bjdata_round_trip(json::bjdata_version_t::draft2);
+}

tests/src/unit-bjdata_round_trip_draft3.cpp

@@ -0,0 +1,22 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  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"
+
+#include <nlohmann/json.hpp>
+using nlohmann::json;
+
+#include "bjdata_round_trip.hpp"
+
+// split from unit-bjdata.cpp, see bjdata_round_trip.hpp; the other half is in
+// unit-bjdata_round_trip_draft2.cpp
+
+TEST_CASE("BJData round-trip invariants (j1 written with Draft 3)")
+{
+    utils::check_bjdata_round_trip(json::bjdata_version_t::draft3);
+}

tests/src/unit-class_lexer.cpp

@@ -13,7 +13,6 @@
 using nlohmann::json;
 
 #include <array> // array
-#include <cctype> // toupper
 #include <cstdint> // uint32_t, uint64_t
 #include <cstdio> // snprintf
 #include <cmath> // isfinite
@@ -336,6 +335,8 @@ TEST_CASE("lexer number fast path")
         }
     }
 
+#if !defined(JSON_NOEXCEPTION)
+    // this section reports parse errors, which abort when exceptions are off
     SECTION("digits accumulated while scanning")
     {
         // The fast path accumulates the digits while it validates them, eight
@@ -414,6 +415,7 @@ TEST_CASE("lexer number fast path")
             }
         }
     }
+#endif
 
     SECTION("integers that do not fit a narrower type become floats")
     {
@@ -597,63 +599,6 @@ TEST_CASE("lexer number fast path")
 #endif
 }
 
-TEST_CASE("lexer literal fast path")
-{
-    // For contiguous input, the rest of a literal is compared at once, and a
-    // mismatch is left to the byte path, which reports the error at the
-    // character that differs. Every truncation and every wrong character of
-    // each literal, at the end of the input or followed by more text, must
-    // give the byte path's result (a std::list is read one character at a
-    // time).
-    const auto outcome = [](const std::string & doc, bool byte_path) -> std::string
-    {
-        JSON_TRY
-        {
-            const std::list<char> chars(doc.begin(), doc.end());
-            return (byte_path ? json::parse(chars.begin(), chars.end()) : json::parse(doc)).dump();
-        }
-        JSON_CATCH (const json::exception & e)
-        {
-            return e.what();
-        }
-    };
-
-    std::vector<std::string> mismatches;
-    for (const std::string literal :
-            {"true", "false", "null"
-            })
-    {
-        std::vector<std::string> variants;
-        for (std::size_t length = 1; length <= literal.size(); ++length)
-        {
-            variants.push_back(literal.substr(0, length));
-        }
-        for (std::size_t i = 1; i < literal.size(); ++i)
-        {
-            std::string changed = literal;
-            changed[i] = 'X';
-            variants.push_back(changed);
-            changed[i] = static_cast<char>(std::toupper(static_cast<unsigned char>(literal[i])));
-            variants.push_back(changed);
-        }
-        for (const auto& variant : variants)
-        {
-            for (const std::string& doc :
-                    {
-                        variant, "[" + variant + "]", "[" + variant, variant + " ", variant + "1", "{\"k\":" + variant + "}"
-                    })
-            {
-                if (outcome(doc, false) != outcome(doc, true))
-                {
-                    mismatches.push_back(doc);
-                }
-            }
-        }
-    }
-    CAPTURE(mismatches)
-    CHECK(mismatches.empty());
-}
-
 TEST_CASE("lexer string fast path")
 {
     // Build a byte string from explicit values: a hex escape in a string
@@ -774,73 +719,6 @@ TEST_CASE("lexer string fast path")
         CAPTURE(mismatches)
         CHECK(mismatches.empty());
     }
-
-    SECTION("special bytes at every offset of the vector blocks")
-    {
-        // With SSE2 or NEON, runs are scanned 16 bytes at a time (after one
-        // SWAR word, or four with NEON), and runs of non-ASCII text are
-        // checked 16 bytes at a time as well. Place every kind of byte that
-        // ends a run at each offset across several blocks, after ASCII and
-        // after CJK text, so sequences also straddle the block boundaries.
-        // The reference is a std::list, which has no contiguous storage and
-        // is therefore read one character at a time.
-        const auto byte_path = [](const std::string & doc) -> std::string
-        {
-            const std::list<char> chars(doc.begin(), doc.end());
-            JSON_TRY
-            {
-                return json::parse(chars.begin(), chars.end()).dump();
-            }
-            JSON_CATCH (const json::exception & e)
-            {
-                return e.what();
-            }
-        };
-        const std::vector<std::string> specials =
-        {
-            "\"", "\\", "\\u00e9", bytes({0x01}), bytes({0x1F}), bytes({0x7F}),
-            bytes({0xC3, 0xA9}), bytes({0xE4, 0xB8, 0xAD}), bytes({0xF0, 0x9F, 0x98, 0x80}),
-            bytes({0xFF}), bytes({0xC3}), bytes({0xE4, 0xB8}), bytes({0xED, 0xA0, 0x80}), bytes({0xC0, 0x80})
-        };
-        const std::string cjk = bytes({0xE4, 0xB8, 0xAD}); // U+4E2D
-
-        std::vector<std::string> mismatches;
-        for (std::size_t offset = 0; offset <= 80; ++offset)
-        {
-            std::string text;
-            while (text.size() < offset)
-            {
-                text += cjk;
-            }
-            for (const auto& prefix :
-                    {
-                        std::string(offset, 'a'), text
-                    })
-            {
-                for (const auto& special : specials)
-                {
-                    // the closing quote right behind, or in a later block
-                    for (const int tail :
-                            {
-                                0, 1, 3, 20
-                            })
-                    {
-                        std::string doc = "[\"";
-                        doc += prefix;
-                        doc += special;
-                        doc.append(static_cast<std::size_t>(tail), 'b');
-                        doc += "\"]";
-                        if (outcome(doc, false) != byte_path(doc))
-                        {
-                            mismatches.push_back(doc);
-                        }
-                    }
-                }
-            }
-        }
-        CAPTURE(mismatches)
-        CHECK(mismatches.empty());
-    }
 #endif
 
     // json::accept() never throws, so the ranges stay covered without exceptions

tests/src/unit-constructor2.cpp

@@ -198,11 +198,11 @@ TEST_CASE("copy constructor and destructor across value types")
         const json src_uint = 7u;
         const json src_float = 2.5;
 
-        json c_null(src_null);
-        json c_bool(src_bool);
-        json c_int(src_int);
-        json c_uint(src_uint);
-        json c_float(src_float);
+        json c_null(src_null); // NOLINT(performance-unnecessary-copy-initialization): tests the copy constructor
+        json c_bool(src_bool); // NOLINT(performance-unnecessary-copy-initialization): tests the copy constructor
+        json c_int(src_int); // NOLINT(performance-unnecessary-copy-initialization): tests the copy constructor
+        json c_uint(src_uint); // NOLINT(performance-unnecessary-copy-initialization): tests the copy constructor
+        json c_float(src_float); // NOLINT(performance-unnecessary-copy-initialization): tests the copy constructor
 
         CHECK(c_null.is_null());
         CHECK(c_bool == true);
@@ -300,12 +300,12 @@ TEST_CASE("copy constructor and destructor across value types")
             REQUIRE(v.size() == 70);
 
             std::vector<json> copy(v);
-            CHECK(copy == v);
+            CHECK((copy == v));
 
             // mutating the copy leaves the original alone
             copy[5] = "changed";
             copy[6].push_back(1);
-            CHECK(copy != v);
+            CHECK((copy != v));
             CHECK(v[5] == std::string(5, 'x'));
             CHECK(v[6].size() == 3);
 

tests/src/unit-diagnostics.cpp

@@ -817,8 +817,8 @@ template<class Key, class T, class IgnoredLess = std::less<Key>,
              struct relocating_map : nlohmann::ordered_map<Key, T, IgnoredLess, Allocator>
 {
     using base_type = nlohmann::ordered_map<Key, T, IgnoredLess, Allocator>;
-    using typename base_type::iterator;
-    using typename base_type::Container;
+    using iterator = typename base_type::iterator;
+    using Container = typename base_type::Container;
     using base_type::base_type;
 
     template<typename... Args>

tests/src/unit-file_input.cpp

@@ -170,6 +170,7 @@ TEST_CASE("parsing from a FILE*")
         check_unlocked(f.get());
     }
 
+#if !defined(JSON_NOEXCEPTION)
     SECTION("the file is unlocked after a parse error")
     {
         const file_ptr f = open_with(name, "[1, 2, x]");
@@ -186,6 +187,8 @@ TEST_CASE("parsing from a FILE*")
         CHECK(std::string(rest.data()) == "]");
     }
 
+#endif // !defined(JSON_NOEXCEPTION)
+
     SECTION("the file can be parsed again and read with stdio afterwards")
     {
         const file_ptr f = open_with(name, "[1] [2] tail");

tests/src/unit-iterators1.cpp

@@ -1637,6 +1637,7 @@ TEST_CASE_TEMPLATE("reverse iteration and member access", Json, nlohmann::json,
     {
         Json j = {1, 2, 3, 4};
 
+        const std::vector<int> reversed = {4, 3, 2, 1};
         auto it = j.end();
         std::vector<int> seen;
         while (it != j.begin())
@@ -1644,7 +1645,7 @@ TEST_CASE_TEMPLATE("reverse iteration and member access", Json, nlohmann::json,
             --it;
             seen.push_back(it->template get<int>());
         }
-        CHECK(seen == std::vector<int> {4, 3, 2, 1});
+        CHECK(seen == reversed);
 
         auto it2 = j.end();
         auto old = it2--;
@@ -1656,14 +1657,14 @@ TEST_CASE_TEMPLATE("reverse iteration and member access", Json, nlohmann::json,
         {
             seen.push_back(r->template get<int>());
         }
-        CHECK(seen == std::vector<int> {4, 3, 2, 1});
+        CHECK(seen == reversed);
 
         seen.clear();
         for (auto r = j.crbegin(); r != j.crend(); ++r)
         {
-            seen.push_back(*r);
+            seen.push_back(r->template get<int>());
         }
-        CHECK(seen == std::vector<int> {4, 3, 2, 1});
+        CHECK(seen == reversed);
     }
 
     SECTION("object: -- and rbegin/rend")

tests/src/unit-json_pointer.cpp

@@ -1230,11 +1230,11 @@ TEST_CASE("JSON pointer array index tokens match strtoull semantics")
 
     SECTION("random tokens")
     {
-        std::mt19937 gen(42);
+        std::mt19937 gen(42); // NOLINT(cert-msc32-c,cert-msc51-cpp,bugprone-random-generator-seed): reproducible
         const std::string alphabet = "0123456789012345678901234567890123456789-+ ex";
         for (int i = 0; i < 5000; ++i)
         {
-            std::string token(static_cast<std::size_t>(gen() % 23), '0');
+            std::string token(gen() % 23, '0');
             for (auto& c : token)
             {
                 c = alphabet[gen() % alphabet.size()];

tests/src/unit-large_json.cpp

@@ -13,8 +13,6 @@ using nlohmann::json;
 
 #include <algorithm>
 #include <string>
-#include <utility>
-#include <vector>
 
 TEST_CASE("tests on very large JSONs")
 {
@@ -55,24 +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")
@@ -244,385 +224,4 @@ 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);
-        }
-    }
 }
-
-namespace
-{
-json nested_array(const std::size_t depth, json leaf)
-{
-    json j = std::move(leaf);
-    for (std::size_t i = 0; i < depth; ++i)
-    {
-        json a = json::array();
-        a.push_back(std::move(j));
-        j = std::move(a);
-    }
-    return j;
-}
-
-json nested_object(const std::size_t depth, json leaf)
-{
-    json j = std::move(leaf);
-    for (std::size_t i = 0; i < depth; ++i)
-    {
-        json o = json::object();
-        o["k"] = std::move(j);
-        j = std::move(o);
-    }
-    return j;
-}
-} // namespace
-
-TEST_CASE("issue #5392 - binary writers on deeply nested values")
-{
-    // 200 is past the point where the writers stop recursing, and still
-    // shallow enough that from_* and operator== (which still recurse) are fine.
-    const json deep_array = nested_array(200, json(0));
-    const json deep_object = nested_object(200, json("x"));
-    const json empty_array = nested_array(200, json::array());
-    const json empty_object = nested_object(200, json::object());
-    const json mixed = nested_object(80, nested_array(80, json(true)));
-
-    SECTION("roundtrip past the recursion bound")
-    {
-        CHECK(json::from_cbor(json::to_cbor(deep_array)) == deep_array);
-        CHECK(json::from_msgpack(json::to_msgpack(deep_array)) == deep_array);
-        CHECK(json::from_ubjson(json::to_ubjson(deep_array)) == deep_array);
-        CHECK(json::from_ubjson(json::to_ubjson(deep_array, true, false)) == deep_array);
-        CHECK(json::from_ubjson(json::to_ubjson(deep_array, true, true)) == deep_array);
-        CHECK(json::from_bjdata(json::to_bjdata(deep_array)) == deep_array);
-        CHECK(json::from_bon8(json::to_bon8(deep_array)) == deep_array);
-
-        CHECK(json::from_cbor(json::to_cbor(deep_object)) == deep_object);
-        CHECK(json::from_msgpack(json::to_msgpack(deep_object)) == deep_object);
-        CHECK(json::from_ubjson(json::to_ubjson(deep_object)) == deep_object);
-        CHECK(json::from_ubjson(json::to_ubjson(deep_object, true, true)) == deep_object);
-        CHECK(json::from_bjdata(json::to_bjdata(deep_object)) == deep_object);
-        CHECK(json::from_bon8(json::to_bon8(deep_object)) == deep_object);
-
-        CHECK(json::from_cbor(json::to_cbor(empty_array)) == empty_array);
-        CHECK(json::from_msgpack(json::to_msgpack(empty_array)) == empty_array);
-        CHECK(json::from_ubjson(json::to_ubjson(empty_array)) == empty_array);
-        CHECK(json::from_ubjson(json::to_ubjson(empty_array, true, true)) == empty_array);
-        CHECK(json::from_bon8(json::to_bon8(empty_array)) == empty_array);
-
-        CHECK(json::from_cbor(json::to_cbor(empty_object)) == empty_object);
-        CHECK(json::from_msgpack(json::to_msgpack(empty_object)) == empty_object);
-        CHECK(json::from_ubjson(json::to_ubjson(empty_object)) == empty_object);
-        CHECK(json::from_bon8(json::to_bon8(empty_object)) == empty_object);
-
-        CHECK(json::from_cbor(json::to_cbor(mixed)) == mixed);
-        CHECK(json::from_msgpack(json::to_msgpack(mixed)) == mixed);
-        CHECK(json::from_ubjson(json::to_ubjson(mixed)) == mixed);
-        CHECK(json::from_bjdata(json::to_bjdata(mixed)) == mixed);
-        CHECK(json::from_bon8(json::to_bon8(mixed)) == mixed);
-    }
-
-    SECTION("the two ways of writing a value meet at the bound")
-    {
-        for (std::size_t depth = 120; depth <= 140; ++depth)
-        {
-            CAPTURE(depth)
-
-            const json array = nested_array(depth, json(7));
-            CHECK(json::from_cbor(json::to_cbor(array)) == array);
-            CHECK(json::from_msgpack(json::to_msgpack(array)) == array);
-            CHECK(json::from_ubjson(json::to_ubjson(array, true, true)) == array);
-            CHECK(json::from_bon8(json::to_bon8(array)) == array);
-
-            const json object = nested_object(depth, json(7));
-            CHECK(json::from_cbor(json::to_cbor(object)) == object);
-            CHECK(json::from_msgpack(json::to_msgpack(object)) == object);
-            CHECK(json::from_bjdata(json::to_bjdata(object)) == object);
-            CHECK(json::from_bon8(json::to_bon8(object)) == object);
-        }
-    }
-
-    SECTION("a BJData ndarray below the bound is still an ndarray")
-    {
-        const json ndarray = json({{"_ArrayType_", "uint8"}, {"_ArraySize_", {2, 3}}, {"_ArrayData_", {1, 2, 3, 4, 5, 6}}});
-        const json invalid = json({{"_ArrayType_", "nope"}, {"_ArraySize_", {1}}, {"_ArrayData_", {1}}});
-
-        const json deep_ndarray = nested_array(140, ndarray);
-        const json deep_invalid = nested_array(140, invalid);
-
-        CHECK(json::from_bjdata(json::to_bjdata(deep_ndarray)) == deep_ndarray);
-        CHECK(json::from_bjdata(json::to_bjdata(deep_invalid)) == deep_invalid);
-        CHECK(json::from_bjdata(json::to_bjdata(ndarray)) == ndarray);
-    }
-
-    SECTION("byte-exact across the switch-over")
-    {
-        // nested one-element arrays around the recursion bound: the exact
-        // bytes a writer produces do not depend on whether it stayed on the
-        // call stack or moved to the heap one partway through
-        for (const std::size_t depth :
-                {
-                    nlohmann::detail::recursion_depth_limit() - 1, nlohmann::detail::recursion_depth_limit(),
-                    nlohmann::detail::recursion_depth_limit() + 1, nlohmann::detail::recursion_depth_limit() + 2
-                })
-        {
-            CAPTURE(depth)
-            const json array = nested_array(depth, json(0));
-
-            std::vector<std::uint8_t> expected_cbor(depth, 0x81);
-            expected_cbor.push_back(0x00);
-            CHECK(json::to_cbor(array) == expected_cbor);
-
-            std::vector<std::uint8_t> expected_msgpack(depth, 0x91);
-            expected_msgpack.push_back(0x00);
-            CHECK(json::to_msgpack(array) == expected_msgpack);
-
-            std::string expected_ubjson(depth, '[');
-            expected_ubjson += "i";
-            expected_ubjson += '\0';
-            expected_ubjson.append(depth, ']');
-            const auto packed_ubjson = json::to_ubjson(array);
-            CHECK(std::string(packed_ubjson.begin(), packed_ubjson.end()) == expected_ubjson);
-
-            std::vector<std::uint8_t> expected_bon8(depth, 0x81);
-            expected_bon8.push_back(0x90);
-            CHECK(json::to_bon8(array) == expected_bon8);
-        }
-    }
-
-    SECTION("a deep object, and a BJData ndarray, past the recursion bound")
-    {
-        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
-
-        const json object = nested_object(depth, json(42));
-        CHECK(json::from_cbor(json::to_cbor(object)) == object);
-        CHECK(json::from_msgpack(json::to_msgpack(object)) == object);
-        CHECK(json::from_ubjson(json::to_ubjson(object, true, true)) == object);
-        CHECK(json::from_bjdata(json::to_bjdata(object)) == object);
-        CHECK(json::from_bon8(json::to_bon8(object)) == object);
-
-        const json ndarray = json({{"_ArrayType_", "uint8"}, {"_ArraySize_", {2, 3}}, {"_ArrayData_", {1, 2, 3, 4, 5, 6}}});
-        const json deep_ndarray = nested_array(depth, ndarray);
-        CHECK(json::from_bjdata(json::to_bjdata(deep_ndarray)) == deep_ndarray);
-    }
-
-    SECTION("a discarded value past the recursion bound still throws type_error.321")
-    {
-        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
-        const json discarded_leaf(json::value_t::discarded);
-        const json deep_discarded = nested_array(depth, discarded_leaf);
-
-        // with diagnostics, the message names the path to the discarded leaf
-#if JSON_DIAGNOSTICS
-        std::string path;
-        for (std::size_t i = 0; i < depth; ++i)
-        {
-            path += "/0";
-        }
-        const std::string prefix = "[json.exception.type_error.321] (" + path + ") ";
-#else
-        const std::string prefix = "[json.exception.type_error.321] ";
-#endif
-
-        CHECK_THROWS_WITH_AS(json::to_cbor(deep_discarded), (prefix + "cannot serialize discarded value to CBOR").c_str(), json::type_error);
-        CHECK_THROWS_WITH_AS(json::to_msgpack(deep_discarded), (prefix + "cannot serialize discarded value to MessagePack").c_str(), json::type_error);
-        CHECK_THROWS_WITH_AS(json::to_ubjson(deep_discarded), (prefix + "cannot serialize discarded value to UBJSON").c_str(), json::type_error);
-        CHECK_THROWS_WITH_AS(json::to_bjdata(deep_discarded), (prefix + "cannot serialize discarded value to BJData").c_str(), json::type_error);
-    }
-
-    SECTION("BON8 past the recursion bound: discarded values and errors")
-    {
-        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
-
-        // BON8 rejects a discarded value (type_error.321), deep or not
-        const json deep_discarded = nested_array(depth, json(json::value_t::discarded));
-        CHECK_THROWS_AS(json::to_bon8(deep_discarded), json::type_error);
-
-        // errors are thrown from below the bound as from above it
-        const json deep_invalid_string = nested_array(depth, json(std::string("\x80")));
-        CHECK_THROWS_AS(json::to_bon8(deep_invalid_string), json::type_error);
-
-        json deep_invalid_key = json::object();
-        deep_invalid_key[std::string("\x80")] = 1;
-        deep_invalid_key = nested_object(depth, deep_invalid_key);
-        CHECK_THROWS_AS(json::to_bon8(deep_invalid_key), json::type_error);
-
-        const json deep_too_large = nested_array(depth, json(9223372036854775808u));
-        CHECK_THROWS_AS(json::to_bon8(deep_too_large), json::out_of_range);
-    }
-
-    SECTION("does not overflow the C++ stack")
-    {
-        const std::size_t depth = 100000;
-        const json j = json::parse(std::string(depth, '[') + "0" + std::string(depth, ']'));
-
-        std::vector<std::uint8_t> packed;
-        CHECK_NOTHROW(packed = json::to_cbor(j));
-        CHECK(json::from_cbor(packed) == j);
-
-        CHECK_NOTHROW(packed = json::to_msgpack(j));
-        CHECK(json::from_msgpack(packed) == j);
-
-        CHECK_NOTHROW(packed = json::to_ubjson(j));
-        CHECK(json::from_ubjson(packed) == j);
-
-        CHECK_NOTHROW(packed = json::to_ubjson(j, true, false));
-        CHECK(json::from_ubjson(packed) == j);
-
-        CHECK_NOTHROW(packed = json::to_bjdata(j));
-        CHECK(json::from_bjdata(packed) == j);
-
-        CHECK_NOTHROW(packed = json::to_bon8(j));
-        CHECK(json::from_bon8(packed) == j);
-    }
-
-    SECTION("BON8 containers with more than four elements past the recursion bound")
-    {
-        // such containers are closed with 0xFE, which the iterative writer
-        // must emit when it leaves them; strings next to each other must
-        // still be separated with 0xFF
-        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
-        json wide_array = json::array({1, "a", "b", json::array(), 5});
-        json wide_object = json({{"k1", "v"}, {"k2", 2}, {"k3", ""}, {"k4", json::object()}, {"k5", nullptr}});
-        for (std::size_t i = 0; i < depth; ++i)
-        {
-            wide_array = json::array({"s", wide_array, "t", wide_object, true});
-            wide_object = json({{"a", wide_object}, {"b", "x"}, {"c", "y"}, {"d", wide_array.size()}, {"e", "z"}});
-        }
-
-        CHECK(json::from_bon8(json::to_bon8(wide_array)) == wide_array);
-        CHECK(json::from_bon8(json::to_bon8(wide_object)) == wide_object);
-    }
-
-    SECTION("regression test for https://issues.oss-fuzz.com/issues/566583014")
-    {
-        // 200000 nested one-element CBOR arrays, the innermost holding null;
-        // round-tripping this used to recurse once per level on the way back
-        // out through to_cbor(), deep enough to overflow the stack
-        std::vector<std::uint8_t> v(200000, 0x81);
-        v.push_back(0xf6);
-        const json j = json::from_cbor(v);
-        CHECK(json::to_cbor(j) == v);
-
-        // the MessagePack analogue: fixarray of 1 nesting down to nil
-        std::vector<std::uint8_t> v_msgpack(200000, 0x91);
-        v_msgpack.push_back(0xc0);
-        const json j_msgpack = json::from_msgpack(v_msgpack);
-        CHECK(json::to_msgpack(j_msgpack) == v_msgpack);
-    }
-
-    SECTION("regression test for https://issues.oss-fuzz.com/issues/572238015")
-    {
-        // the BON8 analogue: 200000 nested one-element arrays down to null
-        std::vector<std::uint8_t> v(200000, 0x81);
-        v.push_back(0xFA);
-        const json j = json::from_bon8(v);
-        CHECK(json::to_bon8(j) == v);
-    }
-}
-

tests/src/unit-large_json_binary_writers.cpp

@@ -0,0 +1,294 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  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"
+
+#include <nlohmann/json.hpp>
+using nlohmann::json;
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <utility>
+#include <vector>
+
+// split from unit-large_json.cpp so that both run in parallel and stay below
+// the ctest timeout under Valgrind
+
+namespace
+{
+json nested_array(const std::size_t depth, json leaf)
+{
+    json j = std::move(leaf);
+    for (std::size_t i = 0; i < depth; ++i)
+    {
+        json a = json::array();
+        a.push_back(std::move(j));
+        j = std::move(a);
+    }
+    return j;
+}
+
+json nested_object(const std::size_t depth, json leaf)
+{
+    json j = std::move(leaf);
+    for (std::size_t i = 0; i < depth; ++i)
+    {
+        json o = json::object();
+        o["k"] = std::move(j);
+        j = std::move(o);
+    }
+    return j;
+}
+} // namespace
+
+TEST_CASE("issue #5392 - binary writers on deeply nested values")
+{
+    // 200 is past the point where the writers stop recursing, and still
+    // shallow enough that from_* and operator== (which still recurse) are fine.
+    const json deep_array = nested_array(200, json(0));
+    const json deep_object = nested_object(200, json("x"));
+    const json empty_array = nested_array(200, json::array());
+    const json empty_object = nested_object(200, json::object());
+    const json mixed = nested_object(80, nested_array(80, json(true)));
+
+    SECTION("roundtrip past the recursion bound")
+    {
+        CHECK(json::from_cbor(json::to_cbor(deep_array)) == deep_array);
+        CHECK(json::from_msgpack(json::to_msgpack(deep_array)) == deep_array);
+        CHECK(json::from_ubjson(json::to_ubjson(deep_array)) == deep_array);
+        CHECK(json::from_ubjson(json::to_ubjson(deep_array, true, false)) == deep_array);
+        CHECK(json::from_ubjson(json::to_ubjson(deep_array, true, true)) == deep_array);
+        CHECK(json::from_bjdata(json::to_bjdata(deep_array)) == deep_array);
+        CHECK(json::from_bon8(json::to_bon8(deep_array)) == deep_array);
+
+        CHECK(json::from_cbor(json::to_cbor(deep_object)) == deep_object);
+        CHECK(json::from_msgpack(json::to_msgpack(deep_object)) == deep_object);
+        CHECK(json::from_ubjson(json::to_ubjson(deep_object)) == deep_object);
+        CHECK(json::from_ubjson(json::to_ubjson(deep_object, true, true)) == deep_object);
+        CHECK(json::from_bjdata(json::to_bjdata(deep_object)) == deep_object);
+        CHECK(json::from_bon8(json::to_bon8(deep_object)) == deep_object);
+
+        CHECK(json::from_cbor(json::to_cbor(empty_array)) == empty_array);
+        CHECK(json::from_msgpack(json::to_msgpack(empty_array)) == empty_array);
+        CHECK(json::from_ubjson(json::to_ubjson(empty_array)) == empty_array);
+        CHECK(json::from_ubjson(json::to_ubjson(empty_array, true, true)) == empty_array);
+        CHECK(json::from_bon8(json::to_bon8(empty_array)) == empty_array);
+
+        CHECK(json::from_cbor(json::to_cbor(empty_object)) == empty_object);
+        CHECK(json::from_msgpack(json::to_msgpack(empty_object)) == empty_object);
+        CHECK(json::from_ubjson(json::to_ubjson(empty_object)) == empty_object);
+        CHECK(json::from_bon8(json::to_bon8(empty_object)) == empty_object);
+
+        CHECK(json::from_cbor(json::to_cbor(mixed)) == mixed);
+        CHECK(json::from_msgpack(json::to_msgpack(mixed)) == mixed);
+        CHECK(json::from_ubjson(json::to_ubjson(mixed)) == mixed);
+        CHECK(json::from_bjdata(json::to_bjdata(mixed)) == mixed);
+        CHECK(json::from_bon8(json::to_bon8(mixed)) == mixed);
+    }
+
+    SECTION("the two ways of writing a value meet at the bound")
+    {
+        for (std::size_t depth = 120; depth <= 140; ++depth)
+        {
+            CAPTURE(depth)
+
+            const json array = nested_array(depth, json(7));
+            CHECK(json::from_cbor(json::to_cbor(array)) == array);
+            CHECK(json::from_msgpack(json::to_msgpack(array)) == array);
+            CHECK(json::from_ubjson(json::to_ubjson(array, true, true)) == array);
+            CHECK(json::from_bon8(json::to_bon8(array)) == array);
+
+            const json object = nested_object(depth, json(7));
+            CHECK(json::from_cbor(json::to_cbor(object)) == object);
+            CHECK(json::from_msgpack(json::to_msgpack(object)) == object);
+            CHECK(json::from_bjdata(json::to_bjdata(object)) == object);
+            CHECK(json::from_bon8(json::to_bon8(object)) == object);
+        }
+    }
+
+    SECTION("a BJData ndarray below the bound is still an ndarray")
+    {
+        const json ndarray = json({{"_ArrayType_", "uint8"}, {"_ArraySize_", {2, 3}}, {"_ArrayData_", {1, 2, 3, 4, 5, 6}}});
+        const json invalid = json({{"_ArrayType_", "nope"}, {"_ArraySize_", {1}}, {"_ArrayData_", {1}}});
+
+        const json deep_ndarray = nested_array(140, ndarray);
+        const json deep_invalid = nested_array(140, invalid);
+
+        CHECK(json::from_bjdata(json::to_bjdata(deep_ndarray)) == deep_ndarray);
+        CHECK(json::from_bjdata(json::to_bjdata(deep_invalid)) == deep_invalid);
+        CHECK(json::from_bjdata(json::to_bjdata(ndarray)) == ndarray);
+    }
+
+    SECTION("byte-exact across the switch-over")
+    {
+        // nested one-element arrays around the recursion bound: the exact
+        // bytes a writer produces do not depend on whether it stayed on the
+        // call stack or moved to the heap one partway through
+        for (const std::size_t depth :
+                {
+                    nlohmann::detail::recursion_depth_limit() - 1, nlohmann::detail::recursion_depth_limit(),
+                    nlohmann::detail::recursion_depth_limit() + 1, nlohmann::detail::recursion_depth_limit() + 2
+                })
+        {
+            CAPTURE(depth)
+            const json array = nested_array(depth, json(0));
+
+            std::vector<std::uint8_t> expected_cbor(depth, 0x81);
+            expected_cbor.push_back(0x00);
+            CHECK(json::to_cbor(array) == expected_cbor);
+
+            std::vector<std::uint8_t> expected_msgpack(depth, 0x91);
+            expected_msgpack.push_back(0x00);
+            CHECK(json::to_msgpack(array) == expected_msgpack);
+
+            std::string expected_ubjson(depth, '[');
+            expected_ubjson += "i";
+            expected_ubjson += '\0';
+            expected_ubjson.append(depth, ']');
+            const auto packed_ubjson = json::to_ubjson(array);
+            CHECK(std::string(packed_ubjson.begin(), packed_ubjson.end()) == expected_ubjson);
+
+            std::vector<std::uint8_t> expected_bon8(depth, 0x81);
+            expected_bon8.push_back(0x90);
+            CHECK(json::to_bon8(array) == expected_bon8);
+        }
+    }
+
+    SECTION("a deep object, and a BJData ndarray, past the recursion bound")
+    {
+        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
+
+        const json object = nested_object(depth, json(42));
+        CHECK(json::from_cbor(json::to_cbor(object)) == object);
+        CHECK(json::from_msgpack(json::to_msgpack(object)) == object);
+        CHECK(json::from_ubjson(json::to_ubjson(object, true, true)) == object);
+        CHECK(json::from_bjdata(json::to_bjdata(object)) == object);
+        CHECK(json::from_bon8(json::to_bon8(object)) == object);
+
+        const json ndarray = json({{"_ArrayType_", "uint8"}, {"_ArraySize_", {2, 3}}, {"_ArrayData_", {1, 2, 3, 4, 5, 6}}});
+        const json deep_ndarray = nested_array(depth, ndarray);
+        CHECK(json::from_bjdata(json::to_bjdata(deep_ndarray)) == deep_ndarray);
+    }
+
+    SECTION("a discarded value past the recursion bound still throws type_error.321")
+    {
+        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
+        const json discarded_leaf(json::value_t::discarded);
+        const json deep_discarded = nested_array(depth, discarded_leaf);
+
+        // with diagnostics, the message names the path to the discarded leaf
+#if JSON_DIAGNOSTICS
+        std::string path;
+        for (std::size_t i = 0; i < depth; ++i)
+        {
+            path += "/0";
+        }
+        const std::string prefix = "[json.exception.type_error.321] (" + path + ") ";
+#else
+        const std::string prefix = "[json.exception.type_error.321] ";
+#endif
+
+        CHECK_THROWS_WITH_AS(json::to_cbor(deep_discarded), (prefix + "cannot serialize discarded value to CBOR").c_str(), json::type_error);
+        CHECK_THROWS_WITH_AS(json::to_msgpack(deep_discarded), (prefix + "cannot serialize discarded value to MessagePack").c_str(), json::type_error);
+        CHECK_THROWS_WITH_AS(json::to_ubjson(deep_discarded), (prefix + "cannot serialize discarded value to UBJSON").c_str(), json::type_error);
+        CHECK_THROWS_WITH_AS(json::to_bjdata(deep_discarded), (prefix + "cannot serialize discarded value to BJData").c_str(), json::type_error);
+    }
+
+    SECTION("BON8 past the recursion bound: discarded values and errors")
+    {
+        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
+
+        // BON8 rejects a discarded value (type_error.321), deep or not
+        const json deep_discarded = nested_array(depth, json(json::value_t::discarded));
+        CHECK_THROWS_AS(json::to_bon8(deep_discarded), json::type_error);
+
+        // errors are thrown from below the bound as from above it
+        const json deep_invalid_string = nested_array(depth, json(std::string("\x80")));
+        CHECK_THROWS_AS(json::to_bon8(deep_invalid_string), json::type_error);
+
+        json deep_invalid_key = json::object();
+        deep_invalid_key[std::string("\x80")] = 1;
+        deep_invalid_key = nested_object(depth, deep_invalid_key);
+        CHECK_THROWS_AS(json::to_bon8(deep_invalid_key), json::type_error);
+
+        const json deep_too_large = nested_array(depth, json(9223372036854775808u));
+        CHECK_THROWS_AS(json::to_bon8(deep_too_large), json::out_of_range);
+    }
+
+    SECTION("does not overflow the C++ stack")
+    {
+        const std::size_t depth = 100000;
+        const json j = json::parse(std::string(depth, '[') + "0" + std::string(depth, ']'));
+
+        std::vector<std::uint8_t> packed;
+        CHECK_NOTHROW(packed = json::to_cbor(j));
+        CHECK(json::from_cbor(packed) == j);
+
+        CHECK_NOTHROW(packed = json::to_msgpack(j));
+        CHECK(json::from_msgpack(packed) == j);
+
+        CHECK_NOTHROW(packed = json::to_ubjson(j));
+        CHECK(json::from_ubjson(packed) == j);
+
+        CHECK_NOTHROW(packed = json::to_ubjson(j, true, false));
+        CHECK(json::from_ubjson(packed) == j);
+
+        CHECK_NOTHROW(packed = json::to_bjdata(j));
+        CHECK(json::from_bjdata(packed) == j);
+
+        CHECK_NOTHROW(packed = json::to_bon8(j));
+        CHECK(json::from_bon8(packed) == j);
+    }
+
+    SECTION("BON8 containers with more than four elements past the recursion bound")
+    {
+        // such containers are closed with 0xFE, which the iterative writer
+        // must emit when it leaves them; strings next to each other must
+        // still be separated with 0xFF
+        const std::size_t depth = nlohmann::detail::recursion_depth_limit() + 50;
+        json wide_array = json::array({1, "a", "b", json::array(), 5});
+        json wide_object = json({{"k1", "v"}, {"k2", 2}, {"k3", ""}, {"k4", json::object()}, {"k5", nullptr}});
+        for (std::size_t i = 0; i < depth; ++i)
+        {
+            wide_array = json::array({"s", wide_array, "t", wide_object, true});
+            wide_object = json({{"a", wide_object}, {"b", "x"}, {"c", "y"}, {"d", wide_array.size()}, {"e", "z"}});
+        }
+
+        CHECK(json::from_bon8(json::to_bon8(wide_array)) == wide_array);
+        CHECK(json::from_bon8(json::to_bon8(wide_object)) == wide_object);
+    }
+
+    SECTION("regression test for https://issues.oss-fuzz.com/issues/566583014")
+    {
+        // 200000 nested one-element CBOR arrays, the innermost holding null;
+        // round-tripping this used to recurse once per level on the way back
+        // out through to_cbor(), deep enough to overflow the stack
+        std::vector<std::uint8_t> v(200000, 0x81);
+        v.push_back(0xf6);
+        const json j = json::from_cbor(v);
+        CHECK(json::to_cbor(j) == v);
+
+        // the MessagePack analogue: fixarray of 1 nesting down to nil
+        std::vector<std::uint8_t> v_msgpack(200000, 0x91);
+        v_msgpack.push_back(0xc0);
+        const json j_msgpack = json::from_msgpack(v_msgpack);
+        CHECK(json::to_msgpack(j_msgpack) == v_msgpack);
+    }
+
+    SECTION("regression test for https://issues.oss-fuzz.com/issues/572238015")
+    {
+        // the BON8 analogue: 200000 nested one-element arrays down to null
+        std::vector<std::uint8_t> v(200000, 0x81);
+        v.push_back(0xFA);
+        const json j = json::from_bon8(v);
+        CHECK(json::to_bon8(j) == v);
+    }
+}
+

tests/src/unit-large_json_conversions.cpp

@@ -0,0 +1,156 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  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"
+
+#include <nlohmann/json.hpp>
+using nlohmann::json;
+
+#include <cstddef>
+#include <string>
+#include <utility>
+#include <vector>
+
+// split from unit-large_json.cpp so that both run in parallel and stay below
+// the ctest timeout under Valgrind
+
+namespace
+{
+
+// 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("issue #5650 - stack overflow converting between specializations")
+{
+    // deep enough to exhaust the call stack, but small enough to stay cheap:
+    // parsing is iterative, so building the values below costs little
+    const std::size_t depth = 100000;
+
+    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-serialization.cpp

@@ -1374,7 +1374,13 @@ void check_dump_against_reference(const std::string& s, const bool with_strict =
     };
     for (const auto error_handler : error_handlers)
     {
+#if defined(JSON_NOEXCEPTION)
+        // a strict dump of invalid UTF-8 calls std::abort() instead of throwing
+        static_cast<void>(with_strict);
+        if (error_handler == json::error_handler_t::strict)
+#else
         if (!with_strict && error_handler == json::error_handler_t::strict)
+#endif
         {
             continue;
         }
@@ -1429,7 +1435,7 @@ TEST_CASE("invalid UTF-8 at every position is handled like the reference")
         "\xF4\x90\x80\x80",
         // sequences cut short by ASCII, a control character, a quote, a
         // backslash, DEL, or the lead byte of a well-formed character
-        "\xC3" "a", "\xE2\x82" "\n", "\xE2\x82\"", "\xF0\x9F\x98\\", "\xC3\x7F", "\xC3\xC3\xA4", "\xE2\xF0\x9F\x98\x80",
+        "\xC3" "a", "\xE2\x82" "\n", "\xE2\x82\"", "\xF0\x9F\x98\\", "\xC3\x7F", "\xC3\xC3\xA4", "\xE2\xF0\x9F\x98\x80", // NOLINT(bugprone-suspicious-missing-comma): "\xC3" "a" ends the hex escape
         // truncated sequences
         "\xC3", "\xE2\x82", "\xF0\x9F\x98"
     };
@@ -1489,7 +1495,7 @@ TEST_CASE("invalid UTF-8 at every position is handled like the reference")
                 {
                     for (const auto& pattern : patterns)
                     {
-                        check_dump_against_reference(make_string(filler, pos, pattern, length - pos), bytes <= (filler.size() == 1 ? 17 : 8));
+                        check_dump_against_reference(make_string(filler, pos, pattern, length - pos), bytes <= (filler.size() == 1 ? 17u : 8u));
                     }
                 }
             }

tests/src/unit-stream-bulk-scan.cpp

@@ -171,8 +171,7 @@ std::vector<std::string> corpus()
         R"("unterminated)", "\"control\x01character\"", "\"ill-formed \xc3\x28 UTF-8\"", R"("bad \x escape")",
         R"("\ud800 lone surrogate")",
         // literals
-        "true", "false", "null", "tru", "nul", "falsey", "[true,false,null]", "nulL", "truex", "[fals e]", "t",
-        "true1", "null null", "[false]",
+        "true", "false", "null", "tru", "nul", "falsey",
         // structures
         "[]", "{}", "[1,2,3]", R"({"a":1,"b":[true,false,null],"c":{"d":"e"}})", "[1,]", R"({"a" 1})", "[[[[[]]]]]",
         // pretty-printed
@@ -191,6 +190,7 @@ std::vector<std::string> corpus()
 
 TEST_CASE("parsing from a std::istream scans the get area in bulk")
 {
+#if !defined(JSON_NOEXCEPTION)
     SECTION("results do not depend on the get area")
     {
         const std::vector<read_mode> read_modes = {read_mode::extract, read_mode::parse, read_mode::parse_lenient};
@@ -211,6 +211,8 @@ TEST_CASE("parsing from a std::istream scans the get area in bulk")
         }
     }
 
+#endif // !defined(JSON_NOEXCEPTION)
+
     SECTION("values are the same as when parsing from a string")
     {
         const std::string input = R"({"name": "nlohmann::json", "numbers": [1, -2, 3.5, 4e10, 18446744073709551615],)"
@@ -228,6 +230,7 @@ TEST_CASE("parsing from a std::istream scans the get area in bulk")
         CHECK(json::parse(ss) == expected);
     }
 
+#if !defined(JSON_NOEXCEPTION)
     SECTION("a token that spans several get areas is reported completely")
     {
         // the error is found after the string has crossed many get areas; the
@@ -282,6 +285,8 @@ TEST_CASE("parsing from a std::istream scans the get area in bulk")
         }
     }
 
+#endif // !defined(JSON_NOEXCEPTION)
+
     SECTION("many values from one stream")
     {
         std::string input;

tests/src/unit-testsuites.cpp

@@ -218,7 +218,11 @@ TEST_CASE("compliance tests from nativejson-benchmark")
             n1e308[0] = '[';
             n1e308[1] = '1';
             n1e308[310] = ']';
+#if JSON_STRICT_NUL_HANDLING
+            n1e308.pop_back(); // a NUL byte after the value is a syntax error in strict mode
+#else
             n1e308[311] = '\0';
+#endif
             TEST_DOUBLE(n1e308, 1E308);
         }
 

tests/src/unit-throw_messages.cpp

@@ -54,8 +54,8 @@ TEST_CASE("exception messages of out-of-line throw sites")
 
     SECTION("at")
     {
-        const json carr = arr;
-        const json cobj = obj;
+        const json& carr = arr;
+        const json& cobj = obj;
         CHECK_MSG((void)arr.at(static_cast<json::size_type>(10)), "[json.exception.out_of_range.401] array index 10 is out of range");
         CHECK_MSG((void)carr.at(static_cast<json::size_type>(3)), "[json.exception.out_of_range.401] array index 3 is out of range");
         CHECK_MSG((void)num.at(static_cast<json::size_type>(0)), "[json.exception.type_error.304] cannot use at() with number");
@@ -65,7 +65,7 @@ TEST_CASE("exception messages of out-of-line throw sites")
         CHECK_MSG((void)num.at("a"), "[json.exception.type_error.304] cannot use at() with number");
 
         nlohmann::ordered_json oobj = {{"a", 1}};
-        const nlohmann::ordered_json coobj = oobj;
+        const nlohmann::ordered_json& coobj = oobj;
         CHECK_MSG((void)oobj.at("z"), "[json.exception.out_of_range.403] key 'z' not found");
         CHECK_MSG((void)coobj.at("z"), "[json.exception.out_of_range.403] key 'z' not found");
         CHECK_MSG((void)coobj.at(std::string("zz")), "[json.exception.out_of_range.403] key 'zz' not found");
@@ -94,9 +94,10 @@ TEST_CASE("exception messages of out-of-line throw sites")
         CHECK_MSG(obj.update(arr.begin(), arr2.end()), "[json.exception.invalid_iterator.210] iterators do not fit");
     }
 
+#if !defined(JSON_NOEXCEPTION) // patch_msg() catches the exceptions, which JSON_NOEXCEPTION turns into std::abort()
     SECTION("patch")
     {
-        const auto patch_msg = [](const char* doc, const char* patch)
+        const auto patch_msg = [](const char* doc, const char* patch) -> std::string
         {
             try
             {
@@ -105,16 +106,23 @@ TEST_CASE("exception messages of out-of-line throw sites")
             }
             catch (const json::exception& e)
             {
-                // with JSON_DIAGNOSTICS, what() names the offending value like "(/0) "; drop it
+                // with JSON_DIAGNOSTICS, what() names the offending value like "(/0) ",
+                // and with JSON_DIAGNOSTIC_POSITIONS its position like "(bytes 0-2) "; drop both
                 std::string msg = e.what();
-                const auto pos = msg.find(" (/");
-                if (pos != std::string::npos)
+                for (const char* marker :
+            {
+                " (/", " (bytes "
+            })
                 {
-                    msg.erase(pos + 1, msg.find(") ", pos) - pos + 1);
+                    const auto pos = msg.find(marker);
+                    if (pos != std::string::npos)
+                    {
+                        msg.erase(pos + 1, msg.find(") ", pos) - pos + 1);
+                    }
                 }
                 return msg;
             }
-            return std::string();
+            return {};
         };
 
         CHECK(patch_msg("{}", "{}") == "[json.exception.parse_error.104] parse error: JSON patch must be an array of objects");
@@ -132,4 +140,5 @@ TEST_CASE("exception messages of out-of-line throw sites")
         CHECK(patch_msg("{\"a\":1}", "[{\"op\":\"test\",\"path\":\"/a\",\"value\":2}]") == "[json.exception.other_error.501] unsuccessful: {\"op\":\"test\",\"path\":\"/a\",\"value\":2}");
         CHECK(patch_msg("{\"a\":1}", "[{\"op\":\"move\",\"path\":\"/a\"}]") == "[json.exception.parse_error.105] parse error: operation 'move' must have member 'from'");
     }
+#endif
 }