Merge branch 'develop' into claude/fix-allocation-exception-safety

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

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

@@ -80,8 +80,8 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
   the end of the file was not reached when `strict` was set to true
 - Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if unsupported features from CBOR were
   used in the given input or if the input is not valid CBOR
-- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a map key is not a string (keys of other
+- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a string was expected as a map key,
-  types are not supported, as JSON object keys are always strings) or a string is malformed
+  but not found
 
 ## Complexity
 

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

@@ -73,8 +73,8 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
   the end of the file was not reached when `strict` was set to true
 - Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if unsupported features from
   MessagePack were used in the given input or if the input is not valid MessagePack
-- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a map key is not a string (keys of other
+- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a string was expected as a map key,
-  types are not supported, as JSON object keys are always strings) or a string is malformed
+  but not found
 
 ## Complexity
 

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

@@ -55,10 +55,6 @@ This implementation does exactly follow this approach, as it uses double precisi
 smaller than `-1.79769313486232e+308` and values greater than `1.79769313486232e+308` will be stored as NaN internally
 and be serialized to `null`.
 
-During deserialization (from JSON text or any of the binary formats), a finite number that does not fit into
-`number_float_t` is rejected with [`out_of_range.406`](../../home/exceptions.md#jsonexceptionout_of_range406), for
-example a double-precision number in a binary format when `number_float_t` is `#!cpp float`.
-
 #### Storage
 
 Floating-point number values are stored directly inside a `basic_json` type.

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

@@ -47,9 +47,8 @@ With the default values for `NumberIntegerType` (`std::int64_t`), the default va
 
 When the default type is used, the maximal integer number that can be stored is `9223372036854775807` (INT64_MAX) and
 the minimal integer number that can be stored is `-9223372036854775808` (INT64_MIN). Integer numbers that are out of
-range will yield over/underflow when used in a constructor. During deserialization (from JSON text or any of the binary
+range will yield over/underflow when used in a constructor. During deserialization, too large or small integer numbers
-formats), too large or small integer numbers will automatically be stored as [`number_unsigned_t`](number_unsigned_t.md)
+will automatically be stored as [`number_unsigned_t`](number_unsigned_t.md) or [`number_float_t`](number_float_t.md).
-or [`number_float_t`](number_float_t.md).
 
 [RFC 8259](https://tools.ietf.org/html/rfc8259) further states:
 > Note that when such software is used, numbers that are integers and are in the range $[-2^{53}+1, 2^{53}-1]$ are

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

@@ -48,9 +48,8 @@ With the default values for `NumberUnsignedType` (`std::uint64_t`), the default
 
 When the default type is used, the maximal integer number that can be stored is `18446744073709551615` (UINT64_MAX) and
 the minimal integer number that can be stored is `0`. Integer numbers that are out of range will yield over/underflow
-when used in a constructor. During deserialization (from JSON text or any of the binary formats), too large or small
+when used in a constructor. During deserialization, too large or small integer numbers will automatically be stored
-integer numbers will automatically be stored as [`number_integer_t`](number_integer_t.md) or
+as [`number_integer_t`](number_integer_t.md) or [`number_float_t`](number_float_t.md).
-[`number_float_t`](number_float_t.md).
 
 [RFC 8259](https://tools.ietf.org/html/rfc8259) further states:
 > Note that when such software is used, numbers that are integers and are in the range $[-2^{53}+1, 2^{53}-1]$ are

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

@@ -168,26 +168,13 @@ The library maps CBOR types to JSON value types as follows:
 !!! warning "Negative integer overflow"
 
     CBOR negative integers (major type 1) are decoded as `-1 - n`. If the encoded magnitude `n` is too large for the
-    result to fit into `number_integer_t` (`std::int64_t` by default), the result is stored as `number_float_t`, like
+    result to fit into `number_integer_t` (`std::int64_t` by default), parsing fails with a
-    a too small integer in JSON text. For example, `-18446744073709551616` (`0x3B` followed by eight `0xFF` bytes) is
+    [`parse_error.112`](../../home/exceptions.md#jsonexceptionparse_error112) exception rather than overflowing
-    stored as `-1.8446744073709552e+19`.
+    silently.
 
 !!! warning "Object keys"
 
-    CBOR allows map keys of any type, whereas JSON only allows strings as keys in object values. Therefore, CBOR maps
+    CBOR allows map keys of any type, whereas JSON only allows strings as keys in object values. Therefore, CBOR maps with keys other than UTF-8 strings are rejected.
-    with keys other than text strings (major type 3) are rejected with a
-    [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with `allow_exceptions` set
-    to `false`, a discarded value) naming the type of the key that was found, for instance:
-
-    ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found an unsigned integer; last byte: 0x01
-    ```
-
-    This applies to the [SAX interface](../parsing/sax_interface.md) as well, as the key is read before it is passed
-    on. This is a deliberate restriction of the library's JSON value model, not an oversight: formats built on CBOR
-    maps with integer keys, such as COSE ([RFC 9052](https://www.rfc-editor.org/rfc/rfc9052.html)) or CWT
-    ([RFC 8392](https://www.rfc-editor.org/rfc/rfc8392.html)), cannot be read with this library and need a
-    general-purpose CBOR library instead.
 
 !!! warning "UTF-8 validation of text strings"
 

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

@@ -138,21 +138,6 @@ The library maps MessagePack types to JSON value types as follows:
 
     Any MessagePack output created by `to_msgpack` can be successfully parsed by `from_msgpack`.
 
-!!! warning "Object keys"
-
-    MessagePack allows map keys of any type, whereas JSON only allows strings as keys in object values. Like the
-    JSON-compatible [profile](https://github.com/msgpack/msgpack/blob/master/spec.md#profile) sketched in the
-    MessagePack specification, this library restricts map keys to `str` values. Maps with keys of any other type are
-    rejected with a [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) exception (or, with
-    `allow_exceptions` set to `false`, a discarded value) naming the type of the key that was found, for instance:
-
-    ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found nil; last byte: 0xC0
-    ```
-
-    This applies to the [SAX interface](../parsing/sax_interface.md) as well, as the key is read before it is passed
-    on. Such input needs a general-purpose MessagePack library instead.
-
 !!! warning "UTF-8 validation of string values"
 
     The MessagePack specification requires `str` values (`fixstr`, `str 8`, `str 16`, `str 32`) to be valid UTF-8.

docs/mkdocs/docs/home/exceptions.md

@@ -331,6 +331,9 @@ An unexpected byte was read in a [binary format](../features/binary_formats/inde
     [json.exception.parse_error.112] parse error at byte 15: syntax error while parsing BSON binary: byte array length cannot be negative, is -1
     ```
     ```
+    [json.exception.parse_error.112] parse error at byte 9: syntax error while parsing CBOR value: negative integer overflow
+    ```
+    ```
     [json.exception.parse_error.112] parse error at byte 5: syntax error while parsing BSON document: document size 6 does not match the number of bytes read (5)
     ```
 
@@ -340,20 +343,13 @@ A string could not be read from a [binary format](../features/binary_formats/ind
 string was read where one was required (for instance as a map key), the string's length specification is invalid, or
 the string's bytes are not valid UTF-8.
 
-CBOR and MessagePack allow map keys of any type, but JSON object keys are always strings. Maps with keys of any other
-type (for instance integers or `null`) are therefore not supported; see the notes on
-[CBOR](../features/binary_formats/cbor.md) and [MessagePack](../features/binary_formats/messagepack.md).
-
 !!! failure "Example messages"
 
     ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found an unsigned integer; last byte: 0x01
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xFF
     ```
     ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found nil; last byte: 0xC0
+    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack string: expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xFF
-    ```
-    ```
-    [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x7C
     ```
     ```
     [json.exception.parse_error.113] parse error at byte 2: syntax error while parsing UBJSON char: byte after 'C' must be in range 0x00..0x7F; last byte: 0x82
@@ -851,18 +847,13 @@ The JSON Patch operations 'remove' and 'add' cannot be applied to the root eleme
 
 ### json.exception.out_of_range.406
 
-A parsed number could not be stored without changing it to NaN or INF. For the binary formats, this happens when a
+A parsed number could not be stored as without changing it to NaN or INF.
-finite floating-point number does not fit into [`number_float_t`](../api/basic_json/number_float_t.md), for example a
-double-precision number when `number_float_t` is `#!cpp float`.
 
-!!! failure "Example messages"
+!!! failure "Example message"
 
     ```
     number overflow parsing '10E1000'
     ```
-    ```
-    [json.exception.out_of_range.406] syntax error while parsing CBOR value: number overflow
-    ```
 
 ### json.exception.out_of_range.407
 

include/nlohmann/detail/conversions/to_json.hpp

@@ -42,6 +42,10 @@ namespace detail
  * j.m_data.m_value.destroy(j.m_data.m_type) to avoid a memory leak in case j contains an
  * allocated value (e.g., a string). See bug issue
  * https://github.com/nlohmann/json/issues/2865 for more information.
+ *
+ * A value that has to be allocated is created before the old one is destroyed:
+ * were it the other way around, an exception while creating the new value would
+ * leave j with the type of the new value, but the pointer to the destroyed old one.
  */
 
 template<value_t> struct external_constructor;
@@ -65,18 +69,20 @@ struct external_constructor<value_t::string>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s)
     {
+        const typename BasicJsonType::json_value value(s);
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::string;
-        j.m_data.m_value = s;
+        j.m_data.m_value = value;
         j.assert_invariant();
     }
 
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s)
     {
+        const typename BasicJsonType::json_value value(std::move(s));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::string;
-        j.m_data.m_value = std::move(s);
+        j.m_data.m_value = value;
         j.assert_invariant();
     }
 
@@ -85,9 +91,10 @@ struct external_constructor<value_t::string>
                              int > = 0 >
     static void construct(BasicJsonType& j, const CompatibleStringType& str)
     {
+        auto* created = j.template create<typename BasicJsonType::string_t>(str);
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::string;
-        j.m_data.m_value.string = j.template create<typename BasicJsonType::string_t>(str);
+        j.m_data.m_value.string = created;
         j.assert_invariant();
     }
 };
@@ -98,18 +105,20 @@ struct external_constructor<value_t::binary>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, const typename BasicJsonType::binary_t& b)
     {
+        const typename BasicJsonType::json_value value(b);
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::binary;
-        j.m_data.m_value = typename BasicJsonType::binary_t(b);
+        j.m_data.m_value = value;
         j.assert_invariant();
     }
 
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, typename BasicJsonType::binary_t&& b)
     {
+        const typename BasicJsonType::json_value value(std::move(b));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::binary;
-        j.m_data.m_value = typename BasicJsonType::binary_t(std::move(b));
+        j.m_data.m_value = value;
         j.assert_invariant();
     }
 };
@@ -159,9 +168,10 @@ struct external_constructor<value_t::array>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr)
     {
+        const typename BasicJsonType::json_value value(arr);
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::array;
-        j.m_data.m_value = arr;
+        j.m_data.m_value = value;
         j.set_parents();
         j.assert_invariant();
     }
@@ -169,9 +179,10 @@ struct external_constructor<value_t::array>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
     {
+        const typename BasicJsonType::json_value value(std::move(arr));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::array;
-        j.m_data.m_value = std::move(arr);
+        j.m_data.m_value = value;
         j.set_parents();
         j.assert_invariant();
     }
@@ -187,9 +198,10 @@ struct external_constructor<value_t::array>
         using std::begin;
         using std::end;
 
+        auto* created = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::array;
-        j.m_data.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
+        j.m_data.m_value.array = created;
         j.set_parents();
         j.assert_invariant();
     }
@@ -197,15 +209,17 @@ struct external_constructor<value_t::array>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, const std::vector<bool>& arr)
     {
-        j.m_data.m_value.destroy(j.m_data.m_type);
+        typename BasicJsonType::array_t elements;
-        j.m_data.m_type = value_t::array;
+        elements.reserve(arr.size());
-        j.m_data.m_value = value_t::array;
-        j.m_data.m_value.array->reserve(arr.size());
         for (const bool x : arr)
         {
-            j.m_data.m_value.array->push_back(x);
+            elements.push_back(x);
-            j.set_parent(j.m_data.m_value.array->back());
         }
+        const typename BasicJsonType::json_value value(std::move(elements));
+        j.m_data.m_value.destroy(j.m_data.m_type);
+        j.m_data.m_type = value_t::array;
+        j.m_data.m_value = value;
+        j.set_parents();
         j.assert_invariant();
     }
 
@@ -213,11 +227,12 @@ struct external_constructor<value_t::array>
              enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
     static void construct(BasicJsonType& j, const std::valarray<T>& arr)
     {
+        typename BasicJsonType::array_t elements(arr.size());
+        std::copy(std::begin(arr), std::end(arr), elements.begin());
+        const typename BasicJsonType::json_value value(std::move(elements));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::array;
-        j.m_data.m_value = value_t::array;
+        j.m_data.m_value = value;
-        j.m_data.m_value.array->resize(arr.size());
-        std::copy(std::begin(arr), std::end(arr), j.m_data.m_value.array->begin());
         j.set_parents();
         j.assert_invariant();
     }
@@ -229,14 +244,16 @@ struct external_constructor<value_t::array>
              enable_if_t<is_compatible_range_view<std::remove_cvref_t<CompatibleArrayType>>::value, int> = 0>
     static void construct(BasicJsonType& j, CompatibleArrayType && arr)
     {
-        j.m_data.m_value.destroy(j.m_data.m_type);
+        typename BasicJsonType::array_t elements;
-        j.m_data.m_type = value_t::array;
-        j.m_data.m_value = value_t::array;
         for (auto&& x : std::forward<CompatibleArrayType>(arr))
         {
-            j.m_data.m_value.array->push_back(x);
+            elements.push_back(x);
-            j.set_parent(j.m_data.m_value.array->back());
         }
+        const typename BasicJsonType::json_value value(std::move(elements));
+        j.m_data.m_value.destroy(j.m_data.m_type);
+        j.m_data.m_type = value_t::array;
+        j.m_data.m_value = value;
+        j.set_parents();
         j.assert_invariant();
     }
 #endif
@@ -248,9 +265,10 @@ struct external_constructor<value_t::object>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj)
     {
+        const typename BasicJsonType::json_value value(obj);
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::object;
-        j.m_data.m_value = obj;
+        j.m_data.m_value = value;
         j.set_parents();
         j.assert_invariant();
     }
@@ -258,9 +276,10 @@ struct external_constructor<value_t::object>
     template<typename BasicJsonType>
     static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
     {
+        const typename BasicJsonType::json_value value(std::move(obj));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::object;
-        j.m_data.m_value = std::move(obj);
+        j.m_data.m_value = value;
         j.set_parents();
         j.assert_invariant();
     }
@@ -272,9 +291,10 @@ struct external_constructor<value_t::object>
         using std::begin;
         using std::end;
 
+        auto* created = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
         j.m_data.m_value.destroy(j.m_data.m_type);
         j.m_data.m_type = value_t::object;
-        j.m_data.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
+        j.m_data.m_value.object = created;
         j.set_parents();
         j.assert_invariant();
     }

include/nlohmann/detail/input/binary_reader.hpp

@@ -559,7 +559,7 @@ class binary_reader
             case 0x01: // double
             {
                 double number{};
-                return get_number<double, true>(input_format_t::bson, number) && emit_float(input_format_t::bson, number);
+                return get_number<double, true>(input_format_t::bson, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 0x02: // string
@@ -600,19 +600,19 @@ class binary_reader
             case 0x10: // int32
             {
                 std::int32_t value{};
-                return get_number<std::int32_t, true>(input_format_t::bson, value) && emit_signed(input_format_t::bson, value);
+                return get_number<std::int32_t, true>(input_format_t::bson, value) && sax->number_integer(value);
             }
 
             case 0x12: // int64
             {
                 std::int64_t value{};
-                return get_number<std::int64_t, true>(input_format_t::bson, value) && emit_signed(input_format_t::bson, value);
+                return get_number<std::int64_t, true>(input_format_t::bson, value) && sax->number_integer(value);
             }
 
             case 0x11: // uint64
             {
                 std::uint64_t value{};
-                return get_number<std::uint64_t, true>(input_format_t::bson, value) && emit_unsigned(input_format_t::bson, value);
+                return get_number<std::uint64_t, true>(input_format_t::bson, value) && sax->number_unsigned(value);
             }
 
             default: // anything else is not supported (yet)
@@ -638,19 +638,14 @@ class binary_reader
         {
             return false;
         }
-
+        const auto max_val = static_cast<NumberType>((std::numeric_limits<number_integer_t>::max)());
-        // the value is -1 - number, which fits into number_integer_t
+        if (number > max_val)
-        // whenever number does
-        if (JSON_HEDLEY_LIKELY(value_in_range_of<number_integer_t>(number)))
         {
-            return sax->number_integer(static_cast<number_integer_t>(-1) - static_cast<number_integer_t>(number));
+            return sax->parse_error(chars_read, get_token_string(),
+                                    parse_error::create(112, chars_read,
+                                            exception_message(input_format_t::cbor, "negative integer overflow", "value"), nullptr));
         }
-
+        return sax->number_integer(static_cast<number_integer_t>(-1) - static_cast<number_integer_t>(number));
-        // like the lexer does for JSON text, store a value too small for
-        // number_integer_t as number_float_t; compute it as long double so
-        // that emit_float sees a finite value and can detect an overflow of
-        // number_float_t
-        return emit_float(input_format_t::cbor, static_cast<long double>(-1) - static_cast<long double>(number));
     }
 
     /*!
@@ -707,25 +702,25 @@ class binary_reader
             case 0x18: // Unsigned integer (one-byte uint8_t follows)
             {
                 std::uint8_t number{};
-                return get_number(input_format_t::cbor, number) && emit_unsigned(input_format_t::cbor, number);
+                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
             }
 
             case 0x19: // Unsigned integer (two-byte uint16_t follows)
             {
                 std::uint16_t number{};
-                return get_number(input_format_t::cbor, number) && emit_unsigned(input_format_t::cbor, number);
+                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
             }
 
             case 0x1A: // Unsigned integer (four-byte uint32_t follows)
             {
                 std::uint32_t number{};
-                return get_number(input_format_t::cbor, number) && emit_unsigned(input_format_t::cbor, number);
+                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
             }
 
             case 0x1B: // Unsigned integer (eight-byte uint64_t follows)
             {
                 std::uint64_t number{};
-                return get_number(input_format_t::cbor, number) && emit_unsigned(input_format_t::cbor, number);
+                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
             }
 
             // Negative integer -1-0x00..-1-0x17 (-1..-24)
@@ -1170,13 +1165,13 @@ class binary_reader
             case 0xFA: // Single-Precision Float (four-byte IEEE 754)
             {
                 float number{};
-                return get_number(input_format_t::cbor, number) && emit_float(input_format_t::cbor, number);
+                return get_number(input_format_t::cbor, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
             {
                 double number{};
-                return get_number(input_format_t::cbor, number) && emit_float(input_format_t::cbor, number);
+                return get_number(input_format_t::cbor, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             default: // anything else (0xFF is handled inside the other types)
@@ -1329,80 +1324,6 @@ class binary_reader
         }
     }
 
-    /*!
-    @brief reads a CBOR object key
-
-    RFC 8949 allows any data item as a map key, but only strings have a
-    counterpart in JSON. A key of any other type is rejected with a message
-    naming that type, rather than the one @ref get_cbor_string gives for a
-    malformed string.
-
-    @param[out] result  created key
-
-    @return whether key creation completed
-    */
-    bool get_cbor_object_key(string_t& result)
-    {
-        // EOF and major type 3 (text string) are left to get_cbor_string
-        if (current == char_traits<char_type>::eof() || (static_cast<unsigned int>(current) & 0xE0u) == 0x60u)
-        {
-            return get_cbor_string(result);
-        }
-
-        const char* found = nullptr;
-        switch (static_cast<unsigned int>(current) >> 5u)
-        {
-            case 0:
-                found = "an unsigned integer";
-                break;
-            case 1:
-                found = "a negative integer";
-                break;
-            case 2:
-                found = "a byte string";
-                break;
-            case 4:
-                found = "an array";
-                break;
-            case 5:
-                found = "a map";
-                break;
-            case 6:
-                found = "a tag";
-                break;
-            default: // major type 7
-                switch (current)
-                {
-                    case 0xF4:
-                    case 0xF5:
-                        found = "a boolean";
-                        break;
-                    case 0xF6:
-                        found = "null";
-                        break;
-                    case 0xF7:
-                        found = "undefined";
-                        break;
-                    case 0xF9:
-                    case 0xFA:
-                    case 0xFB:
-                        found = "a floating-point number";
-                        break;
-                    case 0xFF:
-                        found = "a break stop code";
-                        break;
-                    default:
-                        found = "a simple value";
-                        break;
-                }
-                break;
-        }
-
-        auto last_token = get_token_string();
-        return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read,
-                                exception_message(input_format_t::cbor, concat("only string keys are supported, but found ", found, "; last byte: 0x", last_token), "object key"), nullptr));
-    }
-
     /*!
     @brief reads a definite-length CBOR byte array
 
@@ -1647,7 +1568,7 @@ class binary_reader
                 if (top.is_object)
                 {
                     key.clear();
-                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_object_key(key) || !sax->key(key)))
+                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_string(key) || !sax->key(key)))
                     {
                         return false;
                     }
@@ -1940,61 +1861,61 @@ class binary_reader
             case 0xCA: // float 32
             {
                 float number{};
-                return get_number(input_format_t::msgpack, number) && emit_float(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 0xCB: // float 64
             {
                 double number{};
-                return get_number(input_format_t::msgpack, number) && emit_float(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 0xCC: // uint 8
             {
                 std::uint8_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_unsigned(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
             }
 
             case 0xCD: // uint 16
             {
                 std::uint16_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_unsigned(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
             }
 
             case 0xCE: // uint 32
             {
                 std::uint32_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_unsigned(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
             }
 
             case 0xCF: // uint 64
             {
                 std::uint64_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_unsigned(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
             }
 
             case 0xD0: // int 8
             {
                 std::int8_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_signed(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
             }
 
             case 0xD1: // int 16
             {
                 std::int16_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_signed(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
             }
 
             case 0xD2: // int 32
             {
                 std::int32_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_signed(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
             }
 
             case 0xD3: // int 64
             {
                 std::int64_t number{};
-                return get_number(input_format_t::msgpack, number) && emit_signed(input_format_t::msgpack, number);
+                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
             }
 
             case 0xDC: // array 16
@@ -2148,98 +2069,6 @@ class binary_reader
         }
     }
 
-    /*!
-    @brief reads a MessagePack object key
-
-    The MessagePack specification allows any type as a map key, but only
-    strings have a counterpart in JSON. A key of any other type is rejected
-    with a message naming that type, rather than the one @ref
-    get_msgpack_string gives for a malformed string.
-
-    @param[out] result  created key
-
-    @return whether key creation completed
-    */
-    bool get_msgpack_object_key(string_t& result)
-    {
-        const char* found = nullptr;
-        switch (current)
-        {
-            case 0xC0:
-                found = "nil";
-                break;
-            case 0xC2:
-            case 0xC3:
-                found = "a boolean";
-                break;
-            case 0xCA:
-            case 0xCB:
-                found = "a float";
-                break;
-            case 0xC4:
-            case 0xC5:
-            case 0xC6:
-                found = "a bin";
-                break;
-            case 0xC7:
-            case 0xC8:
-            case 0xC9:
-            case 0xD4:
-            case 0xD5:
-            case 0xD6:
-            case 0xD7:
-            case 0xD8:
-                found = "an ext";
-                break;
-            case 0xCC:
-            case 0xCD:
-            case 0xCE:
-            case 0xCF:
-            case 0xD0:
-            case 0xD1:
-            case 0xD2:
-            case 0xD3:
-                found = "an integer";
-                break;
-            case 0xDC:
-            case 0xDD:
-                found = "an array";
-                break;
-            case 0xDE:
-            case 0xDF:
-                found = "a map";
-                break;
-            default:
-                // fixint, fixmap, and fixarray; strings, EOF, and the unused
-                // byte 0xC1 are left to get_msgpack_string
-                if (current == char_traits<char_type>::eof())
-                {
-                    return get_msgpack_string(result);
-                }
-                if (current <= 0x7F || current >= 0xE0)
-                {
-                    found = "an integer";
-                }
-                else if (current <= 0x8F)
-                {
-                    found = "a map";
-                }
-                else if (current <= 0x9F)
-                {
-                    found = "an array";
-                }
-                else
-                {
-                    return get_msgpack_string(result);
-                }
-                break;
-        }
-
-        auto last_token = get_token_string();
-        return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read,
-                                exception_message(input_format_t::msgpack, concat("only string keys are supported, but found ", found, "; last byte: 0x", last_token), "object key"), nullptr));
-    }
-
     /*!
     @brief reads a MessagePack byte array
 
@@ -2402,7 +2231,7 @@ class binary_reader
                 {
                     get();
                     key.clear();
-                    if (JSON_HEDLEY_UNLIKELY(!get_msgpack_object_key(key) || !sax->key(key)))
+                    if (JSON_HEDLEY_UNLIKELY(!get_msgpack_string(key) || !sax->key(key)))
                     {
                         return false;
                     }
@@ -2927,7 +2756,7 @@ class binary_reader
                         {
                             return sax->parse_error(chars_read, get_token_string(), out_of_range::create(408, exception_message(input_format, "excessive ndarray size caused overflow", "size"), nullptr));
                         }
-                        if (JSON_HEDLEY_UNLIKELY(!emit_unsigned(input_format, i)))
+                        if (JSON_HEDLEY_UNLIKELY(!sax->number_unsigned(static_cast<number_unsigned_t>(i))))
                         {
                             return false;
                         }
@@ -3059,37 +2888,37 @@ class binary_reader
                     break;
                 }
                 std::uint8_t number{};
-                return get_number(input_format, number) && emit_unsigned(input_format, number);
+                return get_number(input_format, number) && sax->number_unsigned(number);
             }
 
             case 'U':
             {
                 std::uint8_t number{};
-                return get_number(input_format, number) && emit_unsigned(input_format, number);
+                return get_number(input_format, number) && sax->number_unsigned(number);
             }
 
             case 'i':
             {
                 std::int8_t number{};
-                return get_number(input_format, number) && emit_signed(input_format, number);
+                return get_number(input_format, number) && sax->number_integer(number);
             }
 
             case 'I':
             {
                 std::int16_t number{};
-                return get_number(input_format, number) && emit_signed(input_format, number);
+                return get_number(input_format, number) && sax->number_integer(number);
             }
 
             case 'l':
             {
                 std::int32_t number{};
-                return get_number(input_format, number) && emit_signed(input_format, number);
+                return get_number(input_format, number) && sax->number_integer(number);
             }
 
             case 'L':
             {
                 std::int64_t number{};
-                return get_number(input_format, number) && emit_signed(input_format, number);
+                return get_number(input_format, number) && sax->number_integer(number);
             }
 
             case 'u':
@@ -3099,7 +2928,7 @@ class binary_reader
                     break;
                 }
                 std::uint16_t number{};
-                return get_number(input_format, number) && emit_unsigned(input_format, number);
+                return get_number(input_format, number) && sax->number_unsigned(number);
             }
 
             case 'm':
@@ -3109,7 +2938,7 @@ class binary_reader
                     break;
                 }
                 std::uint32_t number{};
-                return get_number(input_format, number) && emit_unsigned(input_format, number);
+                return get_number(input_format, number) && sax->number_unsigned(number);
             }
 
             case 'M':
@@ -3119,7 +2948,7 @@ class binary_reader
                     break;
                 }
                 std::uint64_t number{};
-                return get_number(input_format, number) && emit_unsigned(input_format, number);
+                return get_number(input_format, number) && sax->number_unsigned(number);
             }
 
             case 'h':
@@ -3177,13 +3006,13 @@ class binary_reader
             case 'd':
             {
                 float number{};
-                return get_number(input_format, number) && emit_float(input_format, number);
+                return get_number(input_format, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 'D':
             {
                 double number{};
-                return get_number(input_format, number) && emit_float(input_format, number);
+                return get_number(input_format, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 'H':
@@ -3650,13 +3479,13 @@ class binary_reader
             case 0x8E: // binary32
             {
                 float number{};
-                return get_number(input_format_t::bon8, number) && emit_float(input_format_t::bon8, number);
+                return get_number(input_format_t::bon8, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 0x8F: // binary64
             {
                 double number{};
-                return get_number(input_format_t::bon8, number) && emit_float(input_format_t::bon8, number);
+                return get_number(input_format_t::bon8, number) && sax->number_float(static_cast<number_float_t>(number), "");
             }
 
             case 0xF8:
@@ -3722,9 +3551,7 @@ class binary_reader
     @brief pass an integer to the SAX parser
 
     Non-negative integers are passed as unsigned, negative integers as signed
-    numbers, like the other binary formats do. A value that does not fit the
+    numbers, like the other binary formats do.
-    number type is passed as described for @ref emit_unsigned and
-    @ref emit_signed.
 
     @param[in] number  the integer
     @return whether the SAX parser accepted the value
@@ -3733,9 +3560,9 @@ class binary_reader
     {
         if (number >= 0)
         {
-            return emit_unsigned(input_format_t::bon8, static_cast<std::uint64_t>(number));
+            return sax->number_unsigned(static_cast<number_unsigned_t>(number));
         }
-        return emit_signed(input_format_t::bon8, number);
+        return sax->number_integer(static_cast<number_integer_t>(number));
     }
 
     /*!
@@ -3792,7 +3619,8 @@ class binary_reader
             value = (value << 8) | static_cast<std::int64_t>(current);
         }
 
-        return emit_bon8_integer(negative ? -(value + offset) : value + offset);
+        return negative ? sax->number_integer(static_cast<number_integer_t>(-(value + offset)))
+               : sax->number_unsigned(static_cast<number_unsigned_t>(value + offset));
     }
 
     /*!
@@ -4089,88 +3917,6 @@ class binary_reader
         return true;
     }
 
-    /*!
-    @brief pass a signed integer read from the input to the SAX parser
-
-    Like the lexer does for JSON text, a value that does not fit into
-    number_integer_t is passed as number_unsigned_t if it is non-negative and
-    fits there, and as number_float_t otherwise. With the default number
-    types, every integer the binary formats can encode fits, so this only
-    matters for narrower custom number types.
-
-    @tparam NumberType a signed integer type
-    @param[in] format  the current format (for diagnostics)
-    @param[in] number  the integer
-    @return whether the SAX parser accepted the value
-
-    @throw out_of_range.406 if @a number overflows number_float_t (see
-           @ref emit_float)
-    */
-    template<typename NumberType>
-    bool emit_signed(const input_format_t format, const NumberType number)
-    {
-        if (JSON_HEDLEY_LIKELY(value_in_range_of<number_integer_t>(number)))
-        {
-            return sax->number_integer(static_cast<number_integer_t>(number));
-        }
-        if (value_in_range_of<number_unsigned_t>(number))
-        {
-            return sax->number_unsigned(static_cast<number_unsigned_t>(number));
-        }
-        return emit_float(format, number);
-    }
-
-    /*!
-    @brief pass an unsigned integer read from the input to the SAX parser
-
-    Like the lexer does for JSON text, a value that does not fit into
-    number_unsigned_t is passed as number_float_t.
-
-    @tparam NumberType an unsigned integer type
-    @param[in] format  the current format (for diagnostics)
-    @param[in] number  the integer
-    @return whether the SAX parser accepted the value
-
-    @throw out_of_range.406 if @a number overflows number_float_t (see
-           @ref emit_float)
-    */
-    template<typename NumberType>
-    bool emit_unsigned(const input_format_t format, const NumberType number)
-    {
-        if (JSON_HEDLEY_LIKELY(value_in_range_of<number_unsigned_t>(number)))
-        {
-            return sax->number_unsigned(static_cast<number_unsigned_t>(number));
-        }
-        return emit_float(format, number);
-    }
-
-    /*!
-    @brief pass a floating-point number read from the input to the SAX parser
-
-    Like the lexer does for JSON text, a finite value that overflows
-    number_float_t is rejected instead of silently becoming infinity. Infinity
-    and NaN in the input are passed on unchanged. Integers only overflow if
-    number_float_t cannot represent 2^64, e.g., a half-precision type.
-
-    @tparam NumberType a floating-point or integer type
-    @param[in] format  the current format (for diagnostics)
-    @param[in] number  the number
-    @return whether the SAX parser accepted the value
-
-    @throw out_of_range.406 if a finite @a number overflows number_float_t
-    */
-    template<typename NumberType>
-    bool emit_float(const input_format_t format, const NumberType number)
-    {
-        const auto result = static_cast<number_float_t>(number);
-        if (JSON_HEDLEY_UNLIKELY(std::isfinite(number) && !std::isfinite(result)))
-        {
-            return sax->parse_error(chars_read, get_token_string(),
-                                    out_of_range::create(406, exception_message(format, "number overflow", "value"), nullptr));
-        }
-        return sax->number_float(result, "");
-    }
-
     /*!
     @brief create a string by reading characters from the input
 

include/nlohmann/detail/input/lexer.hpp

@@ -206,6 +206,7 @@ class lexer : public lexer_base<BasicJsonType>
     explicit lexer(InputAdapterType&& adapter, bool ignore_comments_ = false, bool discard_number_values_ = false) noexcept
         : ia(std::move(adapter))
         , ignore_comments(ignore_comments_)
+        , decimal_point_char(static_cast<char_int_type>(get_decimal_point()))
         , discard_number_values(discard_number_values_)
     {}
 
@@ -221,7 +222,8 @@ class lexer : public lexer_base<BasicJsonType>
     // locales
     /////////////////////
 
-    /// return the decimal point of the current locale
+    /// return the locale-dependent decimal point
+    JSON_HEDLEY_PURE
     static char get_decimal_point() noexcept
     {
         const auto* loc = localeconv();
@@ -1090,10 +1092,9 @@ class lexer : public lexer_base<BasicJsonType>
             token_type::value_float if number could be successfully scanned,
             token_type::parse_error otherwise
 
-    @note The scanner is independent of the current locale: token_buffer
+    @note The scanner is independent of the current locale. Internally, the
-          always holds `.`. Only the std::strtod fallback of convert_number()
+          locale's decimal point is used instead of `.` to work with the
-          depends on the locale, and it looks up the decimal point right
+          locale-dependent converters.
-          before converting (see convert_float_locale_aware()).
     */
     token_type scan_number()  // lgtm [cpp/use-of-goto] `goto` is used in this function to implement the number-parsing state machine described above. By design, any finite input will eventually reach the "done" state or return token_type::parse_error. In each intermediate state, 1 byte of the input is appended to the token_buffer vector, and only the already initialized variables token_buffer, number_type, and error_message are manipulated.
     {
@@ -1182,7 +1183,7 @@ scan_number_zero:
         {
             case '.':
             {
-                add(current);
+                add(decimal_point_char);
                 decimal_point_position = token_buffer.size() - 1;
                 goto scan_number_decimal1;
             }
@@ -1219,7 +1220,7 @@ scan_number_any1:
 
             case '.':
             {
-                add(current);
+                add(decimal_point_char);
                 decimal_point_position = token_buffer.size() - 1;
                 goto scan_number_decimal1;
             }
@@ -1461,9 +1462,9 @@ scan_number_done:
 
         // Only a number below 1 can carry further insignificant zeros, and only
         // while the count stays at the limit does removing them change the
-        // answer - so this loop is skipped for all but a few tokens. The
+        // answer - so this loop is skipped for all but a few tokens. Note
-        // fraction is located through decimal_point_position rather than by
+        // token_buffer holds the locale's decimal point, so the fraction is
-        // searching '.'.
+        // located through decimal_point_position rather than by searching '.'.
         if (lead_zero != 0)
         {
             JSON_ASSERT(has_dot != 0); // an integer "0" cannot reach the limit
@@ -1481,8 +1482,8 @@ scan_number_done:
     @brief convert the number text in token_buffer to its value and token type
 
     The digit sequence in token_buffer has already been validated (by the
-    scan_number() state machine or by the contiguous fast path) and holds '.'
+    scan_number() state machine or by the contiguous fast path) and holds the
-    as decimal point, independent of the locale. Integers are parsed first and fall
+    locale decimal point in place of '.'. Integers are parsed first and fall
     back to floating point on overflow. This is shared so both scanners produce
     identical results.
 
@@ -1562,7 +1563,7 @@ scan_number_done:
         // integer conversion above overflowed. Prefer std::from_chars
         // (Eisel-Lemire, locale-independent, correctly rounded) when available;
         // otherwise the exact Clinger fast path (double only); otherwise the
-        // locale-aware strtof/strtod/strtold.
+        // locale-aware strtof/strtod.
         if (parse_float_from_chars(num_begin, num_end, value_float))
         {
             return token_type::value_float;
@@ -1571,75 +1572,26 @@ scan_number_done:
         // extra pass over the token's bytes, which otherwise shows up on
         // high-precision inputs such as canada.json
         if (mantissa_fits_clinger(mantissa_end)
-                && parse_float_fast(num_begin, num_end, value_float))
+                && parse_float_fast(num_begin, num_end, decimal_point_char, value_float))
         {
             return token_type::value_float;
         }
 
-        convert_float_locale_aware();
+        char* endptr = nullptr; // NOLINT(misc-const-correctness,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
+        strtof(value_float, token_buffer.data(), &endptr);
+
+        // we checked the number format before
+        JSON_ASSERT(endptr == token_buffer.data() + token_buffer.size());
+
         return token_type::value_float;
     }
 
-    /*!
-    @brief convert the float in token_buffer with strtof/strtod/strtold
-
-    These functions expect the decimal point of the *current* locale, so it is
-    looked up right before the conversion instead of once when the lexer is
-    constructed: a locale change in between (by a parser callback, a SAX
-    handler, or another thread) must not truncate the value (#5198). The
-    token has been validated before, so if the conversion stops early and the
-    decimal point changed in the meantime, the locale changed between the
-    lookup and the call, and the conversion is repeated with the new decimal
-    point. If the decimal point did not change, a retry cannot succeed: the
-    locale's decimal point is not a single character (e.g., the two-byte
-    U+066B of ar_EG.UTF-8 or fa_IR.UTF-8) and cannot be substituted in place.
-    The value strtod parsed up to that point is kept, as before this change.
-
-    Note that changing the locale in another thread *while* strtod runs is
-    undefined behavior of the C library, which this function cannot prevent.
-    */
-    void convert_float_locale_aware()
-    {
-        const bool has_dot = decimal_point_position != std::string::npos;
-        char decimal_point = get_decimal_point();
-        for (;;)
-        {
-            const bool substitute = has_dot && decimal_point != '.';
-            if (substitute)
-            {
-                token_buffer[decimal_point_position] = static_cast<typename string_t::value_type>(decimal_point);
-            }
-
-            char* endptr = nullptr; // NOLINT(misc-const-correctness,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-            strtof(value_float, token_buffer.data(), &endptr);
-
-            if (substitute)
-            {
-                // get_string() hands the token to the SAX interface with '.'
-                token_buffer[decimal_point_position] = '.';
-            }
-
-            if (JSON_HEDLEY_LIKELY(endptr == token_buffer.data() + token_buffer.size()))
-            {
-                return;
-            }
-
-            // retry only if the locale changed; otherwise, this would loop forever
-            const char current_decimal_point = get_decimal_point();
-            if (current_decimal_point == decimal_point)
-            {
-                return;
-            }
-            decimal_point = current_decimal_point;
-        }
-    }
-
     /*!
     @brief contiguous fast path for scanning a number
 
     Parses the whole number token straight from the input buffer, avoiding the
     per-character get()/add() of scan_number(). On success it fills token_buffer
-    (as scan_number() does) and
+    (with the locale decimal point substituted, as scan_number() does) and
     returns the token type. On anything it does not fully recognize as a
     well-formed number it makes no state change and returns
     token_type::uninitialized, so the caller falls back to scan_number(), which
@@ -1755,11 +1707,16 @@ scan_number_done:
         }
 #endif
 
-        // materialize the token exactly as scan_number() would. reset() already
+        // materialize the token exactly as scan_number() would, substituting the
-        // cleared token_buffer, so append() fills it (assign() is avoided
+        // locale decimal point so convert_number()'s strtof fallback stays valid.
-        // because custom string_t types need not provide it)
+        // reset() already cleared token_buffer, so append() fills it (assign() is
+        // avoided because custom string_t types need not provide it)
         token_buffer.append(reinterpret_cast<const typename string_t::value_type*>(data), len);
-        decimal_point_position = dot_index;
+        if (dot_index != std::string::npos)
+        {
+            token_buffer[dot_index] = static_cast<typename string_t::value_type>(decimal_point_char);
+            decimal_point_position = dot_index;
+        }
 
         ia.bulk_skip(len - 1);
         position.chars_read_total += (len - 1);
@@ -2026,7 +1983,11 @@ scan_number_done:
     /// return current string value (implicitly resets the token; useful only once)
     string_t& get_string()
     {
-        // a number token holds '.' regardless of the locale (#4084)
+        // translate decimal points from locale back to '.' (#4084)
+        if (decimal_point_char != '.' && decimal_point_position != std::string::npos)
+        {
+            token_buffer[decimal_point_position] = '.';
+        }
         return token_buffer;
     }
 
@@ -2322,7 +2283,9 @@ scan_number_done:
     number_unsigned_t value_unsigned = 0;
     number_float_t value_float = 0;
 
-    /// the position of the decimal point in token_buffer
+    /// the decimal point
+    const char_int_type decimal_point_char = '.';
+    /// the position of the decimal point in the input
     std::size_t decimal_point_position = std::string::npos;
 
     /// whether the caller (e.g. accept()/json_sax_acceptor) only needs the

include/nlohmann/detail/input/number_parse.hpp

@@ -118,12 +118,14 @@ std::strtod. The parser only activates for number_float_t == double; float and
 long double keep the std::strtof/std::strtold paths (see the templated overload
 below).
 
-@param[in]  first  pointer to the first character of the number
+@param[in]  first          pointer to the first character of the number
-@param[in]  last   pointer past the last character
+@param[in]  last           pointer past the last character
-@param[out] out    the parsed value on success
+@param[in]  decimal_point  the (locale-dependent) decimal point character
+@param[out] out            the parsed value on success
 @return true if the value was parsed exactly; false to fall back to strtod
 */
-inline bool parse_float_fast(const char* first, const char* last, double& out) noexcept
+template<typename DecimalPointType>
+bool parse_float_fast(const char* first, const char* last, DecimalPointType decimal_point, double& out) noexcept
 {
 #if defined(FLT_EVAL_METHOD) && FLT_EVAL_METHOD != 0
     // Clinger's fast path is only exact when double operations are evaluated in
@@ -134,6 +136,7 @@ inline bool parse_float_fast(const char* first, const char* last, double& out) n
     // std::from_chars / std::strtod path.
     static_cast<void>(first);
     static_cast<void>(last);
+    static_cast<void>(decimal_point);
     static_cast<void>(out);
     return false;
 #else
@@ -172,7 +175,7 @@ inline bool parse_float_fast(const char* first, const char* last, double& out) n
             ++num_digits;
             fractional_digits += static_cast<int>(seen_dot);
         }
-        else if (c == '.')
+        else if (static_cast<DecimalPointType>(c) == decimal_point)
         {
             if (JSON_HEDLEY_UNLIKELY(seen_dot))
             {
@@ -257,8 +260,8 @@ inline bool parse_float_fast(const char* first, const char* last, double& out) n
 }
 
 /// fast float path is only exact for `double`; decline for float/long double
-template<typename FloatType>
+template<typename DecimalPointType, typename FloatType>
-bool parse_float_fast(const char* /*first*/, const char* /*last*/, FloatType& /*out*/) noexcept
+bool parse_float_fast(const char* /*first*/, const char* /*last*/, DecimalPointType /*decimal_point*/, FloatType& /*out*/) noexcept
 {
     return false;
 }
@@ -270,7 +273,9 @@ std::from_chars is locale-independent, correctly rounded, and - via the
 Eisel-Lemire algorithm in modern standard libraries - much faster than strtod
 over the whole value range (not just the Clinger subset). It is used only when
 __cpp_lib_to_chars indicates full floating-point support and only when it
-consumes the entire token ([first, last)). An under-/overflow (result_out_of_range) also declines, so
+consumes the entire token ([first, last)); a partial parse means the buffer
+uses a non-'.' locale decimal point, in which case the caller falls back to the
+locale-aware path. An under-/overflow (result_out_of_range) also declines, so
 the caller's strtod fallback supplies the well-defined ±inf/0 result the parser
 expects (side-stepping the P4168 divergence between implementations).
 

include/nlohmann/json.hpp

@@ -1702,8 +1702,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         if (is_an_object)
         {
             // the initializer list is a list of pairs -> create an object
-            m_data.m_type = value_t::object;
             m_data.m_value = value_t::object;
+            m_data.m_type = value_t::object;
 
             for (auto& element_ref : init)
             {
@@ -1725,8 +1725,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
             }
 #endif
             // the initializer list describes an array -> create an array
-            m_data.m_type = value_t::array;
             m_data.m_value.array = create<array_t>(init.begin(), init.end());
+            m_data.m_type = value_t::array;
         }
 
         set_parents();
@@ -1739,8 +1739,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     static basic_json binary(const typename binary_t::container_type& init)
     {
         auto res = basic_json();
-        res.m_data.m_type = value_t::binary;
         res.m_data.m_value = init;
+        res.m_data.m_type = value_t::binary;
         return res;
     }
 
@@ -1750,8 +1750,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     static basic_json binary(const typename binary_t::container_type& init, typename binary_t::subtype_type subtype)
     {
         auto res = basic_json();
-        res.m_data.m_type = value_t::binary;
         res.m_data.m_value = binary_t(init, subtype);
+        res.m_data.m_type = value_t::binary;
         return res;
     }
 
@@ -1761,8 +1761,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     static basic_json binary(typename binary_t::container_type&& init)
     {
         auto res = basic_json();
-        res.m_data.m_type = value_t::binary;
         res.m_data.m_value = std::move(init);
+        res.m_data.m_type = value_t::binary;
         return res;
     }
 
@@ -1772,8 +1772,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
     static basic_json binary(typename binary_t::container_type&& init, typename binary_t::subtype_type subtype)
     {
         auto res = basic_json();
-        res.m_data.m_type = value_t::binary;
         res.m_data.m_value = binary_t(std::move(init), subtype);
+        res.m_data.m_type = value_t::binary;
         return res;
     }
 
@@ -2819,8 +2819,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // implicitly convert a null value to an empty array
         if (is_null())
         {
-            m_data.m_type = value_t::array;
             m_data.m_value.array = create<array_t>();
+            m_data.m_type = value_t::array;
             assert_invariant();
         }
 
@@ -2879,8 +2879,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // implicitly convert a null value to an empty object
         if (is_null())
         {
-            m_data.m_type = value_t::object;
             m_data.m_value.object = create<object_t>();
+            m_data.m_type = value_t::object;
             assert_invariant();
         }
 
@@ -2932,8 +2932,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // implicitly convert a null value to an empty object
         if (is_null())
         {
-            m_data.m_type = value_t::object;
             m_data.m_value.object = create<object_t>();
+            m_data.m_type = value_t::object;
             assert_invariant();
         }
 
@@ -3868,8 +3868,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // transform a null object into an array
         if (is_null())
         {
-            m_data.m_type = value_t::array;
             m_data.m_value = value_t::array;
+            m_data.m_type = value_t::array;
             assert_invariant();
         }
 
@@ -3901,8 +3901,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // transform a null object into an array
         if (is_null())
         {
-            m_data.m_type = value_t::array;
             m_data.m_value = value_t::array;
+            m_data.m_type = value_t::array;
             assert_invariant();
         }
 
@@ -3933,8 +3933,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // transform a null object into an object
         if (is_null())
         {
-            m_data.m_type = value_t::object;
             m_data.m_value = value_t::object;
+            m_data.m_type = value_t::object;
             assert_invariant();
         }
 
@@ -3989,8 +3989,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // transform a null object into an array
         if (is_null())
         {
-            m_data.m_type = value_t::array;
             m_data.m_value = value_t::array;
+            m_data.m_type = value_t::array;
             assert_invariant();
         }
 
@@ -4014,8 +4014,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // transform a null object into an object
         if (is_null())
         {
-            m_data.m_type = value_t::object;
             m_data.m_value = value_t::object;
+            m_data.m_type = value_t::object;
             assert_invariant();
         }
 
@@ -4196,8 +4196,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
         // implicitly convert a null value to an empty object
         if (is_null())
         {
-            m_data.m_type = value_t::object;
             m_data.m_value.object = create<object_t>();
+            m_data.m_type = value_t::object;
             assert_invariant();
         }
 

tests/src/unit-allocator.cpp

@@ -12,6 +12,11 @@
 #include <nlohmann/json.hpp>
 using nlohmann::json;
 
+#include <valarray>
+#if JSON_HAS_RANGES
+    #include <ranges>
+#endif
+
 namespace
 {
 // special test case to check if memory is leaked if constructor throws
@@ -394,3 +399,173 @@ TEST_CASE("bad my_allocator::construct")
         j["test"].push_back("should not leak");
     }
 }
+
+// the no-exceptions CI job skips every CHECK_THROWS_AS, which would leave
+// next_construct_fails set for the next allocation outside a check
+#if !defined(JSON_NOEXCEPTION)
+TEST_CASE("a failed allocation leaves the value unchanged")
+{
+    // create JSON type using the throwing allocator
+    using my_json = nlohmann::basic_json<std::map,
+          std::vector,
+          std::string,
+          bool,
+          std::int64_t,
+          std::uint64_t,
+          double,
+          my_allocator>;
+
+    // Each of these creates a string, array, object, or binary value. The
+    // value must be created before the type is changed: otherwise, a failed
+    // creation left a value of the new type without anything behind it (an
+    // assertion in its destructor, a null pointer everywhere else) or, when
+    // an old value was destroyed first, with a pointer to that destroyed one.
+
+    SECTION("creating a binary value")
+    {
+        const std::vector<std::uint8_t> bytes = {1, 2, 3};
+        my_json _;
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(_ = my_json::binary(bytes), std::bad_alloc&);
+        next_construct_fails = true;
+        CHECK_THROWS_AS(_ = my_json::binary(bytes, 42), std::bad_alloc&);
+        next_construct_fails = true;
+        CHECK_THROWS_AS(_ = my_json::binary(std::vector<std::uint8_t>(bytes)), std::bad_alloc&);
+        next_construct_fails = true;
+        CHECK_THROWS_AS(_ = my_json::binary(std::vector<std::uint8_t>(bytes), 42), std::bad_alloc&);
+        next_construct_fails = false;
+    }
+
+    SECTION("turning a null value into an array or object")
+    {
+        my_json j;
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j[0], std::bad_alloc&);
+        CHECK(j.is_null());
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j["key"], std::bad_alloc&);
+        CHECK(j.is_null());
+
+#ifdef JSON_HAS_CPP_17
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j[std::string_view("key")], std::bad_alloc&);
+        CHECK(j.is_null());
+#endif
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j.push_back(my_json(1)), std::bad_alloc&);
+        CHECK(j.is_null());
+
+        const my_json one = 1;
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j.push_back(one), std::bad_alloc&);
+        CHECK(j.is_null());
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j.push_back(my_json::object_t::value_type("key", 1)), std::bad_alloc&);
+        CHECK(j.is_null());
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j.emplace_back(1), std::bad_alloc&);
+        CHECK(j.is_null());
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j.emplace("key", 1), std::bad_alloc&);
+        CHECK(j.is_null());
+
+        const my_json object = {{"key", 1}};
+        next_construct_fails = true;
+        CHECK_THROWS_AS(j.update(object), std::bad_alloc&);
+        CHECK(j.is_null());
+
+        next_construct_fails = false;
+    }
+
+    SECTION("converting into an existing value")
+    {
+        // to_json replaces the value it is given; the old one must survive a
+        // failed creation of the new one
+        my_json j = "old";
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::string("new")), std::bad_alloc&);
+        CHECK(j == "old");
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::vector<int> {1, 2}), std::bad_alloc&);
+        CHECK(j == "old");
+
+        // with iterator debugging, the default constructor of VS 2015's
+        // std::vector is noexcept but constructs a proxy with the allocator,
+        // which terminates when this allocator throws
+#if !(defined(_MSC_VER) && _MSC_VER < 1910 && defined(_ITERATOR_DEBUG_LEVEL) && _ITERATOR_DEBUG_LEVEL > 0)
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::vector<bool> {true, false}), std::bad_alloc&);
+        CHECK(j == "old");
+#endif
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::map<std::string, int> {{"a", 1}}), std::bad_alloc&);
+        CHECK(j == "old");
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, my_json::binary_t({1, 2})), std::bad_alloc&);
+        CHECK(j == "old");
+
+        // the overloads for lvalues of the value types, for the value types
+        // themselves, and for the remaining compatible types
+        const std::string string = "new";
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, string), std::bad_alloc&);
+        CHECK(j == "old");
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, "new"), std::bad_alloc&);
+        CHECK(j == "old");
+
+        // to_json only moves a binary value that it converted from another
+        // container type, which my_json's std::vector<std::uint8_t> is not
+        using binary_constructor = nlohmann::detail::external_constructor<nlohmann::detail::value_t::binary>;
+        next_construct_fails = true;
+        CHECK_THROWS_AS(binary_constructor::construct(j, my_json::binary_t({1, 2})), std::bad_alloc&);
+        CHECK(j == "old");
+
+        my_json::array_t array = {1, 2};
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, array), std::bad_alloc&);
+        CHECK(j == "old");
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::move(array)), std::bad_alloc&);
+        CHECK(j == "old");
+
+        my_json::object_t object = {{"a", 1}};
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, object), std::bad_alloc&);
+        CHECK(j == "old");
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::move(object)), std::bad_alloc&);
+        CHECK(j == "old");
+
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, std::valarray<int> {1, 2}), std::bad_alloc&);
+        CHECK(j == "old");
+
+#if JSON_HAS_RANGES && !defined(__MINGW32__)
+        const std::vector<int> numbers = {1, 2};
+        next_construct_fails = true;
+        CHECK_THROWS_AS(nlohmann::to_json(j, numbers | std::views::filter([](int /*unused*/)
+        {
+            return true;
+        })), std::bad_alloc&);
+        CHECK(j == "old");
+#endif
+
+        next_construct_fails = false;
+        nlohmann::to_json(j, std::vector<int> {1, 2});
+        CHECK(j == my_json({1, 2}));
+    }
+}
+#endif

tests/src/unit-binary_formats.cpp

@@ -11,12 +11,7 @@
 #include <nlohmann/json.hpp>
 using nlohmann::json;
 
-#include <cmath>
 #include <fstream>
-#include <limits>
-#include <map>
-#include <string>
-#include <vector>
 #include "make_test_data_available.hpp"
 
 TEST_CASE("Binary Formats" * doctest::skip())
@@ -229,139 +224,3 @@ TEST_CASE("Binary Formats" * doctest::skip())
         CHECK((100.0 * double(ubjson_3_size) / double(json_size)) == Approx(89.450));
     }
 }
-
-namespace
-{
-// the binary formats as function pointers for "Binary formats with narrow number types";
-// named functions rather than lambdas, because clang 3.5 cannot convert a lambda
-// to a function pointer in the braced initializer of the format table
-using narrow_json = nlohmann::basic_json<std::map, std::vector, std::string, bool, std::int32_t, std::uint32_t, float>;
-using bytes = std::vector<std::uint8_t>;
-
-bytes encode_cbor(const json& j)
-{
-    return json::to_cbor(j);
-}
-narrow_json decode_cbor(const bytes& v, bool allow_exceptions)
-{
-    return narrow_json::from_cbor(v, true, allow_exceptions);
-}
-
-bytes encode_msgpack(const json& j)
-{
-    return json::to_msgpack(j);
-}
-narrow_json decode_msgpack(const bytes& v, bool allow_exceptions)
-{
-    return narrow_json::from_msgpack(v, true, allow_exceptions);
-}
-
-bytes encode_ubjson(const json& j)
-{
-    return json::to_ubjson(j);
-}
-narrow_json decode_ubjson(const bytes& v, bool allow_exceptions)
-{
-    return narrow_json::from_ubjson(v, true, allow_exceptions);
-}
-
-bytes encode_bjdata(const json& j)
-{
-    return json::to_bjdata(j);
-}
-narrow_json decode_bjdata(const bytes& v, bool allow_exceptions)
-{
-    return narrow_json::from_bjdata(v, true, allow_exceptions);
-}
-
-// BSON can only store numbers as object members
-bytes encode_bson(const json& j)
-{
-    return json::to_bson(json{{"a", j}});
-}
-narrow_json decode_bson(const bytes& v, bool allow_exceptions)
-{
-    const auto result = narrow_json::from_bson(v, true, allow_exceptions);
-    return result.is_discarded() ? result : result.at("a");
-}
-
-bytes encode_bon8(const json& j)
-{
-    return json::to_bon8(j);
-}
-narrow_json decode_bon8(const bytes& v, bool allow_exceptions)
-{
-    return narrow_json::from_bon8(v, true, allow_exceptions);
-}
-
-} // namespace
-
-TEST_CASE("Binary formats with narrow number types")
-{
-    // Numbers that do not fit the number types are handled like the lexer
-    // handles them in JSON text: an integer that fits neither integer type is
-    // stored as a floating-point number, and a finite floating-point number
-    // that overflows number_float_t is rejected with out_of_range.406.
-    struct binary_format
-    {
-        const char* name;
-        bytes (*encode)(const json&);
-        narrow_json (*decode)(const bytes&, bool);
-    };
-
-    const std::vector<binary_format> formats =
-    {
-        {"CBOR", encode_cbor, decode_cbor},
-        {"MessagePack", encode_msgpack, decode_msgpack},
-        {"UBJSON", encode_ubjson, decode_ubjson},
-        {"BJData", encode_bjdata, decode_bjdata},
-        {"BSON", encode_bson, decode_bson},
-        {"BON8", encode_bon8, decode_bon8},
-    };
-
-    for (const auto& format : formats)
-    {
-        const std::string name = format.name;
-        INFO("format := ", name);
-        const auto roundtrip = [&format](const json & j)
-        {
-            return format.decode(format.encode(j), true);
-        };
-
-        // integers that fit keep their type
-        CHECK(roundtrip(json(-5)).is_number_integer());
-        CHECK(roundtrip(json(-5)).get<std::int32_t>() == -5);
-        CHECK(roundtrip(json(3000000000u)).is_number_unsigned());
-        CHECK(roundtrip(json(3000000000u)).get<std::uint32_t>() == 3000000000u);
-
-        // integers that fit neither integer type are stored as float
-        CHECK(roundtrip(json(5000000000u)).is_number_float());
-        CHECK(roundtrip(json(5000000000u)).get<float>() == 5000000000.0f);
-        if (name != "BON8") // BON8 cannot encode integers above INT64_MAX
-        {
-            CHECK(roundtrip(json(10000000000000000000u)).is_number_float());
-            CHECK(roundtrip(json(10000000000000000000u)).get<float>() == 10000000000000000000.0f);
-        }
-        CHECK(roundtrip(json(-3000000000LL)).is_number_float());
-        CHECK(roundtrip(json(-3000000000LL)).get<float>() == -3000000000.0f);
-        CHECK(roundtrip(json(-5000000000LL)).is_number_float());
-        CHECK(roundtrip(json(-5000000000LL)).get<float>() == -5000000000.0f);
-
-        // floating-point numbers that fit
-        CHECK(roundtrip(json(1.5)).get<float>() == 1.5f);
-        const auto just_above_max = std::nextafter(static_cast<double>((std::numeric_limits<float>::max)()),
-                                    std::numeric_limits<double>::infinity());
-        CHECK(roundtrip(json(just_above_max)).get<float>() == (std::numeric_limits<float>::max)());
-
-        // infinity and NaN are passed on
-        CHECK(std::isinf(roundtrip(json(std::numeric_limits<double>::infinity())).get<float>()));
-        CHECK(std::isnan(roundtrip(json(std::numeric_limits<double>::quiet_NaN())).get<float>()));
-
-        // finite floating-point numbers that overflow number_float_t are rejected
-        const std::string message = "[json.exception.out_of_range.406] syntax error while parsing " + name
-                                    + " value: number overflow";
-        CHECK_THROWS_WITH_AS(roundtrip(json(1e300)), message.c_str(), narrow_json::out_of_range&);
-        CHECK_THROWS_WITH_AS(roundtrip(json(-1e300)), message.c_str(), narrow_json::out_of_range&);
-        CHECK(format.decode(format.encode(json(1e300)), false).is_discarded());
-    }
-}

tests/src/unit-cbor.cpp

@@ -1830,51 +1830,10 @@ TEST_CASE("CBOR")
         SECTION("invalid string in map")
         {
             json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xa1, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found a break stop code; last byte: 0xFF", json::parse_error&);
+            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xa1, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xFF", json::parse_error&);
             CHECK(json::from_cbor(std::vector<uint8_t>({0xa1, 0xff, 0x01}), true, false).is_discarded());
         }
 
-        SECTION("non-string key (see #2766 and #3381)")
-        {
-            // only text strings map to JSON object keys; any other key is
-            // rejected with a message naming its type
-            const std::vector<std::pair<std::vector<std::uint8_t>, std::string>> cases =
-            {
-                {{0xA1, 0x01, 0x01}, "an unsigned integer; last byte: 0x01"},
-                {{0xA1, 0x20, 0x01}, "a negative integer; last byte: 0x20"},
-                {{0xA1, 0x41, 0x61, 0x01}, "a byte string; last byte: 0x41"},
-                {{0xA1, 0x80, 0x01}, "an array; last byte: 0x80"},
-                {{0xA1, 0xA0, 0x01}, "a map; last byte: 0xA0"},
-                {{0xA1, 0xC0, 0x61, 0x61, 0x01}, "a tag; last byte: 0xC0"},
-                {{0xA1, 0xF4, 0x01}, "a boolean; last byte: 0xF4"},
-                {{0xA1, 0xF5, 0x01}, "a boolean; last byte: 0xF5"},
-                {{0xA1, 0xF6, 0x01}, "null; last byte: 0xF6"},
-                {{0xA1, 0xF7, 0x01}, "undefined; last byte: 0xF7"},
-                {{0xA1, 0xF9, 0x3C, 0x00, 0x01}, "a floating-point number; last byte: 0xF9"},
-                {{0xA1, 0xFA, 0x3F, 0x80, 0x00, 0x00, 0x01}, "a floating-point number; last byte: 0xFA"},
-                {{0xA1, 0xFB, 0x3F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "a floating-point number; last byte: 0xFB"},
-                {{0xA1, 0xE0, 0x01}, "a simple value; last byte: 0xE0"},
-                {{0xA1, 0xF8, 0x20, 0x01}, "a simple value; last byte: 0xF8"},
-                // indefinite-length map
-                {{0xBF, 0x01, 0x01, 0xFF}, "an unsigned integer; last byte: 0x01"},
-            };
-
-            for (const auto& c : cases)
-            {
-                CAPTURE(c.first)
-                const std::string expected = "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found " + c.second;
-                json _;
-                CHECK_THROWS_WITH_AS(_ = json::from_cbor(c.first), expected.c_str(), json::parse_error&);
-                CHECK(json::from_cbor(c.first, true, false).is_discarded());
-            }
-
-            // a key of major type 3 with a reserved length is still reported as
-            // a malformed string, and a missing key as the end of input
-            json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1})), "[json.exception.parse_error.110] parse error at byte 2: syntax error while parsing CBOR string: unexpected end of input", json::parse_error&);
-            CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1, 0x7C, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x7C", json::parse_error&);
-        }
-
         SECTION("invalid UTF-8 in string (see #5529)")
         {
             // a two-character text string (major type 3) whose bytes are not
@@ -2325,7 +2284,7 @@ TEST_CASE("CBOR indefinite-length strings do not recurse per chunk")
     SECTION("a break marker outside an indefinite-length string is not a string")
     {
         // 0xFF only closes a string that was opened; on its own it is not one
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1, 0xFF, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found a break stop code; last byte: 0xFF", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(std::vector<uint8_t>({0xA1, 0xFF, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xFF", json::parse_error&);
     }
 }
 
@@ -3187,8 +3146,7 @@ TEST_CASE("Tagged values")
         // CBOR encodes negative integers as: result = -1 - n
         // For type 0x3B, n is an 8-byte uint64_t. Valid range for n with
         // the default int64_t is [0, INT64_MAX], producing results in [INT64_MIN, -1].
-        // When n > INT64_MAX, the result exceeds int64_t range and is stored
+        // When n > INT64_MAX, the result exceeds int64_t range and is rejected.
-        // as a floating-point number, as the lexer does for JSON text.
 
         SECTION("n = 0 is valid (result = -1)")
         {
@@ -3209,34 +3167,33 @@ TEST_CASE("Tagged values")
             CHECK(result.get<int64_t>() == (std::numeric_limits<int64_t>::min)());
         }
 
-        SECTION("n = INT64_MAX + 1 is stored as float")
+        SECTION("n = INT64_MAX + 1 is rejected (overflow)")
         {
             // n = INT64_MAX + 1 (0x8000000000000000)
-            // result = -1 - n = -9223372036854775809, which exceeds int64_t range;
+            // result = -1 - n = -9223372036854775809, which exceeds int64_t range
-            // the nearest double is -9223372036854775808.0
             const std::vector<uint8_t> input = {0x3B, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
-            const auto result = json::from_cbor(input);
+            json _;
-            CHECK(result.is_number_float());
+            CHECK_THROWS_WITH_AS(_ = json::from_cbor(input),
-            CHECK(result.get<double>() == -9223372036854775808.0);
+                                 "[json.exception.parse_error.112] parse error at byte 9: syntax error while parsing CBOR value: negative integer overflow",
-            CHECK(result == json::parse("-9223372036854775809"));
+                                 json::parse_error);
         }
 
-        SECTION("n = UINT64_MAX is stored as float")
+        SECTION("n = UINT64_MAX is rejected (overflow)")
         {
             // n = UINT64_MAX (0xFFFFFFFFFFFFFFFF)
             // result = -1 - n = -18446744073709551616, which exceeds int64_t range
             const std::vector<uint8_t> input = {0x3B, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
-            const auto result = json::from_cbor(input);
+            json _;
-            CHECK(result.is_number_float());
+            CHECK_THROWS_WITH_AS(_ = json::from_cbor(input),
-            CHECK(result.get<double>() == -18446744073709551616.0);
+                                 "[json.exception.parse_error.112] parse error at byte 9: syntax error while parsing CBOR value: negative integer overflow",
-            CHECK(result == json::parse("-18446744073709551616"));
+                                 json::parse_error);
         }
 
-        SECTION("overflow with allow_exceptions=false is not an error")
+        SECTION("overflow with allow_exceptions=false returns discarded")
         {
             const std::vector<uint8_t> input = {0x3B, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
             const auto result = json::from_cbor(input, true, false);
-            CHECK(result.is_number_float());
+            CHECK(result.is_discarded());
         }
     }
 

tests/src/unit-class_lexer.cpp

@@ -666,7 +666,7 @@ TEST_CASE("parse_float_fast declines what it cannot convert exactly")
     // always safe: the caller then falls back to a slower, exact conversion.
     const auto fast = [](const std::string & s, double & out)
     {
-        return nlohmann::detail::parse_float_fast(s.data(), s.data() + s.size(), out);
+        return nlohmann::detail::parse_float_fast(s.data(), s.data() + s.size(), '.', out);
     };
     double out = 0;
 

tests/src/unit-locale-cpp.cpp

@@ -12,12 +12,7 @@
 #include <nlohmann/json.hpp>
 using nlohmann::json;
 
-#include <array>
 #include <clocale>
-#include <map>
-#include <string>
-#include <utility>
-#include <vector>
 
 struct ParserImpl final: public nlohmann::json_sax<json>
 {
@@ -180,208 +175,3 @@ TEST_CASE("locale-dependent test (LC_NUMERIC=de_DE)")
         MESSAGE("locale de_DE is not usable");
     }
 }
-
-namespace
-{
-// records the numbers of a flat array and switches LC_NUMERIC to the given
-// locale once the array opens - after the lexer was constructed, but before
-// any number in the array is lexed
-struct LocaleSwitchingSax final: public nlohmann::json_sax<json>
-{
-    explicit LocaleSwitchingSax(const char* switch_to)
-        : locale_after_open(switch_to)
-    {}
-
-    bool null() override
-    {
-        return true;
-    }
-    bool boolean(bool /*val*/) override
-    {
-        return true;
-    }
-    bool number_integer(json::number_integer_t /*val*/) override
-    {
-        return true;
-    }
-    bool number_unsigned(json::number_unsigned_t /*val*/) override
-    {
-        return true;
-    }
-    bool number_float(json::number_float_t val, const json::string_t& s) override
-    {
-        values.push_back(val);
-        strings.push_back(s);
-        return true;
-    }
-    bool string(json::string_t& /*val*/) override
-    {
-        return true;
-    }
-    bool binary(json::binary_t& /*val*/) override
-    {
-        return true;
-    }
-    bool start_object(std::size_t /*val*/) override
-    {
-        return true;
-    }
-    bool key(json::string_t& /*val*/) override
-    {
-        return true;
-    }
-    bool end_object() override
-    {
-        return true;
-    }
-    bool start_array(std::size_t /*val*/) override
-    {
-        switched = std::setlocale(LC_NUMERIC, locale_after_open.c_str()) != nullptr;
-        return true;
-    }
-    bool end_array() override
-    {
-        return true;
-    }
-    bool parse_error(std::size_t /*val*/, const std::string& /*val*/, const nlohmann::detail::exception& /*val*/) override
-    {
-        return false;
-    }
-
-    std::string locale_after_open;
-    bool switched = false;
-    std::vector<json::number_float_t> values {}; // NOLINT(readability-redundant-member-init)
-    std::vector<json::string_t> strings {}; // NOLINT(readability-redundant-member-init)
-};
-} // namespace
-
-TEST_CASE("locale changes between lexer construction and number conversion (#5198)")
-{
-    // The numbers are chosen so that the conversion also takes the strtod
-    // fallback, which honors the locale that is current at conversion time:
-    // too many significant digits for Clinger's fast path, an underflow that
-    // std::from_chars rejects, and a plain value.
-    const std::vector<std::string> numbers = {"3.14159265358979323846", "1.5e-400", "12.34", "-0.000123456789012345678"};
-    std::string text = "[";
-    for (const auto& n : numbers)
-    {
-        text += (text.size() == 1 ? "" : ",") + n;
-    }
-    text += "]";
-
-    using long_double_json = nlohmann::basic_json<std::map, std::vector, std::string, bool, std::int64_t, std::uint64_t, long double>;
-
-    // reference values, parsed without a locale switch
-    REQUIRE(std::setlocale(LC_NUMERIC, "C") != nullptr);
-    const json expected = json::parse(text);
-    const long_double_json expected_ld = long_double_json::parse(text);
-
-    const std::array<std::pair<const char*, const char*>, 2> transitions =
-    {
-        {
-            {"C", "de_DE"},
-            {"de_DE", "C"}
-        }
-    };
-
-    for (const auto& transition : transitions)
-    {
-        CAPTURE(transition.first);
-        CAPTURE(transition.second);
-
-        if (std::setlocale(LC_NUMERIC, transition.first) == nullptr)
-        {
-            MESSAGE("locale is not usable");
-            continue;
-        }
-
-        // SAX parsing
-        {
-            LocaleSwitchingSax sax(transition.second);
-            CHECK(json::sax_parse(text, &sax));
-            if (sax.switched)
-            {
-                CHECK(sax.values == expected.get<std::vector<json::number_float_t>>());
-                CHECK(sax.strings == numbers);
-            }
-        }
-
-        // DOM parsing with a callback
-        {
-            bool switched = false;
-            const auto cb = [&](int /*depth*/, json::parse_event_t event, json& /*parsed*/) noexcept
-            {
-                if (event == json::parse_event_t::array_start)
-                {
-                    switched = std::setlocale(LC_NUMERIC, transition.second) != nullptr;
-                }
-                return true;
-            };
-            const json j = json::parse(text, cb);
-            if (switched)
-            {
-                CHECK(j == expected);
-            }
-        }
-
-        // a long double goes through std::strtold unless std::from_chars supports it
-        {
-            bool switched = false;
-            const auto cb = [&](int /*depth*/, long_double_json::parse_event_t event, long_double_json& /*parsed*/) noexcept
-            {
-                if (event == long_double_json::parse_event_t::array_start)
-                {
-                    switched = std::setlocale(LC_NUMERIC, transition.second) != nullptr;
-                }
-                return true;
-            };
-            const long_double_json j = long_double_json::parse(text, cb);
-            if (switched)
-            {
-                CHECK(j == expected_ld);
-            }
-        }
-    }
-
-    CHECK(std::setlocale(LC_NUMERIC, "C") != nullptr);
-}
-
-TEST_CASE("locale with a multi-byte decimal point")
-{
-    // Some locales use a decimal point that is not a single character, e.g.
-    // U+066B ARABIC DECIMAL SEPARATOR (two bytes in UTF-8). It cannot be
-    // substituted in place for '.', so the strtod fallback stops early. The
-    // conversion must still terminate rather than retry forever.
-    const std::array<const char*, 6> names = {{"ar_EG.UTF-8", "ar_SA.UTF-8", "fa_IR.UTF-8", "ps_AF.UTF-8", "ar_EG", "fa_IR"}};
-    bool tested = false;
-    for (const char* name : names)
-    {
-        if (std::setlocale(LC_NUMERIC, name) == nullptr)
-        {
-            continue;
-        }
-        const std::string decimal_point = std::localeconv()->decimal_point;
-        if (decimal_point.size() < 2)
-        {
-            continue;
-        }
-        CAPTURE(name);
-        tested = true;
-
-        // too many significant digits for Clinger's fast path, and an underflow
-        // that std::from_chars rejects: both reach the strtod fallback
-        json j;
-        CHECK_NOTHROW(j = json::parse("[3.14159265358979323846, 1.5e-400, -0.000123456789012345678]"));
-        CHECK(j.is_array());
-        CHECK(json::accept("3.14159265358979323846"));
-
-        // a value the locale-independent paths convert is not affected
-        CHECK(json::parse("12.5") == 12.5);
-    }
-    if (!tested)
-    {
-        MESSAGE("no locale with a multi-byte decimal point is usable");
-    }
-
-    CHECK(std::setlocale(LC_NUMERIC, "C") != nullptr);
-}

tests/src/unit-msgpack.cpp

@@ -1551,69 +1551,10 @@ TEST_CASE("MessagePack")
         SECTION("invalid string in map")
         {
             json _;
-            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found an integer; last byte: 0xFF", json::parse_error&);
+            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81, 0xff, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack string: expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xFF", json::parse_error&);
             CHECK(json::from_msgpack(std::vector<uint8_t>({0x81, 0xff, 0x01}), true, false).is_discarded());
         }
 
-        SECTION("non-string key (see #3381)")
-        {
-            // only strings map to JSON object keys; any other key is rejected
-            // with a message naming its type
-            const std::vector<std::pair<std::vector<std::uint8_t>, std::string>> cases =
-            {
-                {{0x81, 0xC0, 0x01}, "nil; last byte: 0xC0"},
-                {{0x81, 0xC2, 0x01}, "a boolean; last byte: 0xC2"},
-                {{0x81, 0xC3, 0x01}, "a boolean; last byte: 0xC3"},
-                {{0x81, 0xCA, 0x3F, 0x80, 0x00, 0x00, 0x01}, "a float; last byte: 0xCA"},
-                {{0x81, 0xCB, 0x3F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "a float; last byte: 0xCB"},
-                {{0x81, 0xC4, 0x00, 0x01}, "a bin; last byte: 0xC4"},
-                {{0x81, 0xC5, 0x00, 0x00, 0x01}, "a bin; last byte: 0xC5"},
-                {{0x81, 0xC6, 0x00, 0x00, 0x00, 0x00, 0x01}, "a bin; last byte: 0xC6"},
-                {{0x81, 0xC7, 0x00, 0x01, 0x01}, "an ext; last byte: 0xC7"},
-                {{0x81, 0xC8, 0x00, 0x00, 0x01, 0x01}, "an ext; last byte: 0xC8"},
-                {{0x81, 0xC9, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}, "an ext; last byte: 0xC9"},
-                {{0x81, 0xD4, 0x01, 0x00, 0x01}, "an ext; last byte: 0xD4"},
-                {{0x81, 0xD5, 0x01, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD5"},
-                {{0x81, 0xD6, 0x01, 0x00, 0x00, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD6"},
-                {{0x81, 0xD7, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD7"},
-                {{0x81, 0xD8, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, "an ext; last byte: 0xD8"},
-                {{0x81, 0xCC, 0x01, 0x01}, "an integer; last byte: 0xCC"},
-                {{0x81, 0xCD, 0x00, 0x01, 0x01}, "an integer; last byte: 0xCD"},
-                {{0x81, 0xCE, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xCE"},
-                {{0x81, 0xCF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xCF"},
-                {{0x81, 0xD0, 0x01, 0x01}, "an integer; last byte: 0xD0"},
-                {{0x81, 0xD1, 0x00, 0x01, 0x01}, "an integer; last byte: 0xD1"},
-                {{0x81, 0xD2, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xD2"},
-                {{0x81, 0xD3, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}, "an integer; last byte: 0xD3"},
-                {{0x81, 0x00, 0x01}, "an integer; last byte: 0x00"},
-                {{0x81, 0x7F, 0x01}, "an integer; last byte: 0x7F"},
-                {{0x81, 0xE0, 0x01}, "an integer; last byte: 0xE0"},
-                {{0x81, 0x80, 0x01}, "a map; last byte: 0x80"},
-                {{0x81, 0x8F, 0x01}, "a map; last byte: 0x8F"},
-                {{0x81, 0xDE, 0x00, 0x00, 0x01}, "a map; last byte: 0xDE"},
-                {{0x81, 0xDF, 0x00, 0x00, 0x00, 0x00, 0x01}, "a map; last byte: 0xDF"},
-                {{0x81, 0x90, 0x01}, "an array; last byte: 0x90"},
-                {{0x81, 0x9F, 0x01}, "an array; last byte: 0x9F"},
-                {{0x81, 0xDC, 0x00, 0x00, 0x01}, "an array; last byte: 0xDC"},
-                {{0x81, 0xDD, 0x00, 0x00, 0x00, 0x00, 0x01}, "an array; last byte: 0xDD"},
-            };
-
-            for (const auto& c : cases)
-            {
-                CAPTURE(c.first)
-                const std::string expected = "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack object key: only string keys are supported, but found " + c.second;
-                json _;
-                CHECK_THROWS_WITH_AS(_ = json::from_msgpack(c.first), expected.c_str(), json::parse_error&);
-                CHECK(json::from_msgpack(c.first, true, false).is_discarded());
-            }
-
-            json _;
-            // the unused byte 0xC1 is still reported as a malformed string
-            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81, 0xC1, 0x01})), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing MessagePack string: expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0xC1", json::parse_error&);
-            // a missing key is still reported as the end of input
-            CHECK_THROWS_WITH_AS(_ = json::from_msgpack(std::vector<uint8_t>({0x81})), "[json.exception.parse_error.110] parse error at byte 2: syntax error while parsing MessagePack string: unexpected end of input", json::parse_error&);
-        }
-
         SECTION("invalid UTF-8 in string (see #5529)")
         {
             // a fixstr of length 2 (0xA0 | 2) whose bytes are not valid UTF-8

tests/src/unit-regression1.cpp

@@ -1018,7 +1018,7 @@ TEST_CASE("regression tests 1")
         };
 
         json _;
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR object key: only string keys are supported, but found an array; last byte: 0x98", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec), "[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x98", json::parse_error&);
 
         // related test case: nonempty UTF-8 string (indefinite length)
         std::vector<uint8_t> const vec1 {0x7f, 0x61, 0x61};
@@ -1065,7 +1065,7 @@ TEST_CASE("regression tests 1")
         };
 
         json _;
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec1), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR object key: only string keys are supported, but found a map; last byte: 0xB4", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec1), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xB4", json::parse_error&);
 
         // related test case: double-precision
         std::vector<uint8_t> const vec2
@@ -1077,7 +1077,7 @@ TEST_CASE("regression tests 1")
             0x96, 0x96, 0xb4, 0xb4, 0xfa, 0x94, 0x94, 0x61,
             0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0xfb
         };
-        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec2), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR object key: only string keys are supported, but found a map; last byte: 0xB4", json::parse_error&);
+        CHECK_THROWS_WITH_AS(_ = json::from_cbor(vec2), "[json.exception.parse_error.113] parse error at byte 13: syntax error while parsing CBOR string: expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0xB4", json::parse_error&);
     }
 
     SECTION("issue #452 - Heap-buffer-overflow (OSS-Fuzz issue 585)")