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Compare commits
| Author | SHA1 | Date | |
|---|---|---|---|
 Niels Lohmann
|
bc9370c291 | ||
|
Niels Lohmann
|
666801a2c6 |
@@ -224,5 +224,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
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1. Added in version 1.0.0.
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2. Added in version 1.0.0.
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3. Added in version 3.11.0.
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3. Added in version 3.11.0. Fixed in version 3.13.0 to consistently accept `std::string_view`-convertible keys, as
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already supported by [`operator[]`](operator[].md), [`value`](value.md), [`find`](find.md), and other lookup
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functions.
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4. Added in version 2.0.0.
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@@ -119,7 +119,9 @@ Logarithmic in the size of the JSON object.
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## Version history
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1. Added in version 3.11.0.
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2. Added in version 3.6.0. Extended template `KeyType` to support comparable types in version 3.11.0.
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2. Added in version 3.6.0. Extended template `KeyType` to support comparable types in version 3.11.0. Fixed in
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version 3.13.0 to consistently accept `std::string_view`-convertible keys, as already supported by
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[`operator[]`](operator[].md), [`at`](at.md), [`value`](value.md), and other lookup functions.
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3. Added in version 3.7.0.
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4. Deleted overloads for integral key types added in version 3.13.0 to reject such calls at compile time instead of
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causing undefined behavior at runtime.
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@@ -84,6 +84,8 @@ Logarithmic in the size of the JSON object.
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## Version history
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1. Added in version 3.11.0.
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2. Added in version 1.0.0. Changed parameter `key` type to `KeyType&&` in version 3.11.0.
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2. Added in version 1.0.0. Changed parameter `key` type to `KeyType&&` in version 3.11.0. Fixed in version 3.13.0 to
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consistently accept `std::string_view`-convertible keys, as already supported by [`operator[]`](operator[].md),
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[`at`](at.md), [`value`](value.md), and other lookup functions.
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3. Deleted overload for integral key types added in version 3.13.0 to reject such calls at compile time instead of
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causing undefined behavior at runtime.
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@@ -213,5 +213,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
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1. Added in version 1.0.0. Added support for binary types in version 3.8.0.
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2. Added in version 1.0.0. Added support for binary types in version 3.8.0.
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3. Added in version 1.0.0.
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4. Added in version 3.11.0.
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4. Added in version 3.11.0. Fixed in version 3.13.0 to consistently accept `std::string_view`-convertible keys, as
|
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already supported by [`operator[]`](operator[].md), [`at`](at.md), [`value`](value.md), and other lookup
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functions.
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5. Added in version 1.0.0.
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@@ -88,6 +88,8 @@ Logarithmic in the size of the JSON object.
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## Version history
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|
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1. Added in version 3.11.0.
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2. Added in version 1.0.0. Changed to support comparable types in version 3.11.0.
|
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2. Added in version 1.0.0. Changed to support comparable types in version 3.11.0. Fixed in version 3.13.0 to
|
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consistently accept `std::string_view`-convertible keys, as already supported by [`operator[]`](operator[].md),
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[`at`](at.md), [`value`](value.md), and other lookup functions.
|
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3. Deleted overloads for integral key types added in version 3.13.0 to reject such calls at compile time instead of
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causing undefined behavior at runtime.
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@@ -195,7 +195,9 @@ changes to any JSON value.
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1. Added in version 1.0.0. Changed parameter `default_value` type from `const ValueType&` to `ValueType&&` in version
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3.11.0. Deleted overload for integral key types added in version 3.13.0 to reject such calls at compile time
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instead of causing undefined behavior at runtime.
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2. Added in version 3.11.0. Made `ValueType` the first template parameter in version 3.11.2.
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2. Added in version 3.11.0. Made `ValueType` the first template parameter in version 3.11.2. Fixed in version 3.13.0
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to consistently accept `std::string_view`-convertible keys, as already supported by
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[`operator[]`](operator[].md), [`at`](at.md), [`find`](find.md), and other lookup functions.
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3. Added in version 2.0.2. Extended to work with arrays in version 3.13.0, including fixing an issue where resolving
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`ptr` through an array unexpectedly threw `out_of_range` instead of returning the resolved element (or
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`default_value`, as documented).
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@@ -748,6 +748,30 @@ using is_usable_as_key_type = typename std::conditional <
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std::true_type,
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std::false_type >::type;
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#ifdef JSON_HAS_CPP_17
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// type trait to check if KeyType can only be used as an object key after
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// converting it to std::string_view: it is convertible to std::string_view, the
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// object's comparator cannot compare it with object_t::key_type directly, but
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// can compare a std::string_view. JSON pointers and JSON iterators are ruled out
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// first, so that the conversion checks are never instantiated for them (a JSON
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// pointer's deprecated conversion to string_t would be named otherwise).
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template < typename BasicJsonType, typename KeyTypeCVRef, typename KeyType = uncvref_t<KeyTypeCVRef>,
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bool = is_json_pointer<KeyType>::value || is_json_iterator_of<BasicJsonType, KeyType>::value >
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struct is_string_view_convertible_key_type : std::false_type {};
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template<typename BasicJsonType, typename KeyTypeCVRef, typename KeyType>
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struct is_string_view_convertible_key_type<BasicJsonType, KeyTypeCVRef, KeyType, false>
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: std::integral_constant < bool,
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std::is_convertible<KeyTypeCVRef, std::string_view>::value
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&& !is_usable_as_key_type<typename BasicJsonType::object_comparator_t,
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typename BasicJsonType::object_t::key_type, KeyTypeCVRef, true, false>::value
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&& is_usable_as_key_type<typename BasicJsonType::object_comparator_t,
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typename BasicJsonType::object_t::key_type, std::string_view, true, false>::value > {};
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#else
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template<typename BasicJsonType, typename KeyTypeCVRef>
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struct is_string_view_convertible_key_type : std::false_type {};
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#endif
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// type trait to check if KeyType can be used as an object key
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// true if:
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// - KeyType is comparable with BasicJsonType::object_t::key_type
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@@ -761,9 +785,7 @@ using is_usable_as_basic_json_key_type = typename std::conditional <
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typename BasicJsonType::object_t::key_type, KeyTypeCVRef,
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RequireTransparentComparator, ExcludeObjectKeyType>::value
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&& !is_json_iterator_of<BasicJsonType, KeyType>::value)
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#ifdef JSON_HAS_CPP_17
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|| std::is_convertible<KeyType, std::string_view>::value
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#endif
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|| is_string_view_convertible_key_type<BasicJsonType, KeyTypeCVRef>::value
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, std::true_type,
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std::false_type >::type;
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+53
-60
@@ -807,6 +807,24 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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return it;
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}
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/// @brief the key to look up an object member with: the key itself, or its
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/// std::string_view if the object can only be searched with that
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template < typename KeyType, detail::enable_if_t <
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!detail::is_string_view_convertible_key_type<basic_json_t, KeyType>::value, int > = 0 >
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static KeyType && lookup_key(KeyType && key) noexcept
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{
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return std::forward<KeyType>(key);
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}
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#ifdef JSON_HAS_CPP_17
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template < typename KeyType, detail::enable_if_t <
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detail::is_string_view_convertible_key_type<basic_json_t, KeyType>::value, int > = 0 >
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static std::string_view lookup_key(KeyType && key)
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{
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return std::forward<KeyType>(key);
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}
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#endif
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/// @brief erase an element from the object and return the following one
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/// Not every map returns an iterator from erase(iterator): some containers
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/// (e.g., Abseil's hash maps) return void to avoid computing a successor
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@@ -1004,38 +1022,18 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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using copy_scratch_value_t = std::pair<typename object_t::key_type, basic_json>;
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using copy_scratch_t = std::vector<copy_scratch_value_t, AllocatorType<copy_scratch_value_t>>;
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/// @brief tag selecting the constructor below; used only to build the
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/// elements of a deep copy (@ref copy_array_level, @ref copy_object_level)
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struct copy_construct_tag {};
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public:
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/*!
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@brief construct a null value whose base class - and, with @ref
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JSON_DIAGNOSTIC_POSITIONS, positions - are copied from @a src
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Copy-constructing @ref json_base_class_t here, rather than default-
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constructing the element and assigning its base class afterwards, means
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that copying a @ref basic_json only ever requires a copy-constructible
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base class, and never a move-assignable one as well.
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@note this constructor has to be public: @ref copy_array_level and
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@ref copy_object_level reach it through @ref array_t's or @ref
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object_t's own emplace_back(), which constructs the element from
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outside @ref basic_json and so cannot call a private constructor.
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@ref copy_construct_tag is private, though, and nothing in the
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public interface hands out a value of it, so outside code can still
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never name it to call this constructor itself.
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*/
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basic_json(copy_construct_tag /*unused*/, const basic_json& src)
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: json_base_class_t(src)
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#if JSON_DIAGNOSTIC_POSITIONS
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, start_position(src.start_position)
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, end_position(src.end_position)
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#endif
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/// @brief copy everything of @a src into @a dst but its type and value
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static void copy_metadata(const basic_json& src, basic_json& dst)
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{
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}
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// a custom base class is only required to be copy-constructible and
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// move-assignable, so the copy has to go through a temporary
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static_cast<json_base_class_t&>(dst) = json_base_class_t(static_cast<const json_base_class_t&>(src));
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private:
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#if JSON_DIAGNOSTIC_POSITIONS
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dst.start_position = src.start_position;
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dst.end_position = src.end_position;
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#endif
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}
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/*!
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@brief copy the value of @a src into @a dst, which must not be structured
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@@ -1099,11 +1097,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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}
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/*!
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@brief finish the copy @a dst of @a src that a @ref copy_construct_tag
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constructor started, other than the children of an object or array
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@brief copy everything of @a src into the null value @a dst but the children
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@a dst already has @a src's base class and, with @ref
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JSON_DIAGNOSTIC_POSITIONS, positions; only its value is still missing.
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Objects and arrays are not copied here; they are appended to @a worklist to
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be created later by @ref copy_iteratively. Until that happens, @a dst remains
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a null value, so that a partially built copy can be destroyed at any point
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@@ -1111,6 +1106,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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*/
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static void copy_shallow(const basic_json& src, basic_json& dst, copy_worklist_t& worklist)
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{
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copy_metadata(src, dst);
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|
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if (src.m_data.m_type == value_t::object || src.m_data.m_type == value_t::array)
|
||||
{
|
||||
// defer: dst stays a null value until its container exists
|
||||
@@ -1131,19 +1128,15 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
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{
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const array_t& src_array = *src.m_data.m_value.array;
|
||||
|
||||
// create all elements up front: growing the array afterwards could
|
||||
// invalidate the pointers that are handed to the worklist; resize()
|
||||
// rather than the fill constructor, because not every array type
|
||||
// provides the latter (e.g., ones without a matching allocator-aware
|
||||
// fill constructor)
|
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dst.m_data.m_value.array = create<array_t>();
|
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// only now that the array exists may dst stop being a null value
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||||
dst.m_data.m_type = value_t::array;
|
||||
|
||||
// create every element - its base class already copy-constructed from
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||||
// its counterpart in src, via the copy_construct_tag constructor -
|
||||
// before any of their addresses are handed to worklist below: growing
|
||||
// the array while that is going on could reallocate it and invalidate
|
||||
// addresses taken from an earlier iteration
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||||
for (const auto& src_element : src_array)
|
||||
{
|
||||
dst.m_data.m_value.array->emplace_back(copy_construct_tag{}, src_element);
|
||||
}
|
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dst.m_data.m_value.array->resize(src_array.size());
|
||||
|
||||
auto dst_it = dst.m_data.m_value.array->begin();
|
||||
for (auto src_it = src_array.cbegin(); src_it != src_array.cend(); ++src_it, ++dst_it)
|
||||
@@ -1161,14 +1154,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
// build the complete key skeleton and hand it to the object's range
|
||||
// constructor: adding the keys one by one would be quadratic for object
|
||||
// types that are backed by a vector, such as nlohmann::ordered_map; each
|
||||
// value's base class is already copy-constructed from its counterpart
|
||||
// in src, via the copy_construct_tag constructor
|
||||
// types that are backed by a vector, such as nlohmann::ordered_map
|
||||
scratch.clear();
|
||||
scratch.reserve(src_object.size());
|
||||
for (const auto& element : src_object)
|
||||
{
|
||||
scratch.emplace_back(element.first, basic_json(copy_construct_tag{}, element.second));
|
||||
scratch.emplace_back(element.first, basic_json());
|
||||
}
|
||||
|
||||
dst.m_data.m_value.object = create<object_t>(std::make_move_iterator(scratch.begin()),
|
||||
@@ -2794,7 +2785,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_THROW(type_error::create(304, detail::concat("cannot use at() with ", type_name()), this));
|
||||
}
|
||||
|
||||
auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
if (it == m_data.m_value.object->end())
|
||||
{
|
||||
JSON_THROW(out_of_range::create(403, detail::concat("key '", string_t(std::forward<KeyType>(key)), "' not found"), this));
|
||||
@@ -2832,7 +2823,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_THROW(type_error::create(304, detail::concat("cannot use at() with ", type_name()), this));
|
||||
}
|
||||
|
||||
auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
if (it == m_data.m_value.object->end())
|
||||
{
|
||||
JSON_THROW(out_of_range::create(403, detail::concat("key '", string_t(std::forward<KeyType>(key)), "' not found"), this));
|
||||
@@ -2975,7 +2966,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
// operator[] only works for objects
|
||||
if (JSON_HEDLEY_LIKELY(is_object()))
|
||||
{
|
||||
auto result = m_data.m_value.object->emplace(std::forward<KeyType>(key), nullptr);
|
||||
auto result = m_data.m_value.object->emplace(lookup_key(std::forward<KeyType>(key)), nullptr);
|
||||
return set_parent(result.first->second);
|
||||
}
|
||||
|
||||
@@ -2991,7 +2982,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
// const operator[] only works for objects
|
||||
if (JSON_HEDLEY_LIKELY(is_object()))
|
||||
{
|
||||
auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
JSON_ASSERT(it != m_data.m_value.object->end());
|
||||
return it->second;
|
||||
}
|
||||
@@ -3001,8 +2992,10 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
private:
|
||||
template<typename KeyType>
|
||||
using is_comparable_with_object_key = detail::is_comparable <
|
||||
object_comparator_t, const typename object_t::key_type&, KeyType >;
|
||||
using is_comparable_with_object_key = std::integral_constant < bool,
|
||||
detail::is_comparable <
|
||||
object_comparator_t, const typename object_t::key_type&, KeyType >::value
|
||||
|| detail::is_string_view_convertible_key_type<basic_json_t, KeyType>::value >;
|
||||
|
||||
template<typename ValueType>
|
||||
using value_return_type = std::conditional <
|
||||
@@ -3389,7 +3382,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_THROW(type_error::create(307, detail::concat("cannot use erase() with ", type_name()), this));
|
||||
}
|
||||
|
||||
const auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
const auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
if (it != m_data.m_value.object->end())
|
||||
{
|
||||
m_data.m_value.object->erase(it);
|
||||
@@ -3416,7 +3409,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
detail::is_usable_as_basic_json_key_type<basic_json_t, KeyType>::value, int> = 0>
|
||||
size_type erase(KeyType && key)
|
||||
{
|
||||
return erase_internal(std::forward<KeyType>(key));
|
||||
return erase_internal(lookup_key(std::forward<KeyType>(key)));
|
||||
}
|
||||
|
||||
/// @brief remove element from a JSON array given an index
|
||||
@@ -3496,7 +3489,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
if (is_object())
|
||||
{
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
}
|
||||
|
||||
return result;
|
||||
@@ -3512,7 +3505,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
if (is_object())
|
||||
{
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
}
|
||||
|
||||
return result;
|
||||
@@ -3535,7 +3528,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
size_type count(KeyType && key) const
|
||||
{
|
||||
// return 0 for all nonobject types
|
||||
return is_object() ? m_data.m_value.object->count(std::forward<KeyType>(key)) : 0;
|
||||
return is_object() ? m_data.m_value.object->count(lookup_key(std::forward<KeyType>(key))) : 0;
|
||||
}
|
||||
|
||||
/// @brief check the existence of an element in a JSON object
|
||||
@@ -3553,7 +3546,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_HEDLEY_WARN_UNUSED_RESULT
|
||||
bool contains(KeyType && key) const
|
||||
{
|
||||
return is_object() && m_data.m_value.object->find(std::forward<KeyType>(key)) != m_data.m_value.object->end();
|
||||
return is_object() && m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key))) != m_data.m_value.object->end();
|
||||
}
|
||||
|
||||
/// @brief check the existence of an element in a JSON object given a JSON pointer
|
||||
|
||||
@@ -4756,6 +4756,30 @@ using is_usable_as_key_type = typename std::conditional <
|
||||
std::true_type,
|
||||
std::false_type >::type;
|
||||
|
||||
#ifdef JSON_HAS_CPP_17
|
||||
// type trait to check if KeyType can only be used as an object key after
|
||||
// converting it to std::string_view: it is convertible to std::string_view, the
|
||||
// object's comparator cannot compare it with object_t::key_type directly, but
|
||||
// can compare a std::string_view. JSON pointers and JSON iterators are ruled out
|
||||
// first, so that the conversion checks are never instantiated for them (a JSON
|
||||
// pointer's deprecated conversion to string_t would be named otherwise).
|
||||
template < typename BasicJsonType, typename KeyTypeCVRef, typename KeyType = uncvref_t<KeyTypeCVRef>,
|
||||
bool = is_json_pointer<KeyType>::value || is_json_iterator_of<BasicJsonType, KeyType>::value >
|
||||
struct is_string_view_convertible_key_type : std::false_type {};
|
||||
|
||||
template<typename BasicJsonType, typename KeyTypeCVRef, typename KeyType>
|
||||
struct is_string_view_convertible_key_type<BasicJsonType, KeyTypeCVRef, KeyType, false>
|
||||
: std::integral_constant < bool,
|
||||
std::is_convertible<KeyTypeCVRef, std::string_view>::value
|
||||
&& !is_usable_as_key_type<typename BasicJsonType::object_comparator_t,
|
||||
typename BasicJsonType::object_t::key_type, KeyTypeCVRef, true, false>::value
|
||||
&& is_usable_as_key_type<typename BasicJsonType::object_comparator_t,
|
||||
typename BasicJsonType::object_t::key_type, std::string_view, true, false>::value > {};
|
||||
#else
|
||||
template<typename BasicJsonType, typename KeyTypeCVRef>
|
||||
struct is_string_view_convertible_key_type : std::false_type {};
|
||||
#endif
|
||||
|
||||
// type trait to check if KeyType can be used as an object key
|
||||
// true if:
|
||||
// - KeyType is comparable with BasicJsonType::object_t::key_type
|
||||
@@ -4769,9 +4793,7 @@ using is_usable_as_basic_json_key_type = typename std::conditional <
|
||||
typename BasicJsonType::object_t::key_type, KeyTypeCVRef,
|
||||
RequireTransparentComparator, ExcludeObjectKeyType>::value
|
||||
&& !is_json_iterator_of<BasicJsonType, KeyType>::value)
|
||||
#ifdef JSON_HAS_CPP_17
|
||||
|| std::is_convertible<KeyType, std::string_view>::value
|
||||
#endif
|
||||
|| is_string_view_convertible_key_type<BasicJsonType, KeyTypeCVRef>::value
|
||||
, std::true_type,
|
||||
std::false_type >::type;
|
||||
|
||||
@@ -27734,6 +27756,24 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
return it;
|
||||
}
|
||||
|
||||
/// @brief the key to look up an object member with: the key itself, or its
|
||||
/// std::string_view if the object can only be searched with that
|
||||
template < typename KeyType, detail::enable_if_t <
|
||||
!detail::is_string_view_convertible_key_type<basic_json_t, KeyType>::value, int > = 0 >
|
||||
static KeyType && lookup_key(KeyType && key) noexcept
|
||||
{
|
||||
return std::forward<KeyType>(key);
|
||||
}
|
||||
|
||||
#ifdef JSON_HAS_CPP_17
|
||||
template < typename KeyType, detail::enable_if_t <
|
||||
detail::is_string_view_convertible_key_type<basic_json_t, KeyType>::value, int > = 0 >
|
||||
static std::string_view lookup_key(KeyType && key)
|
||||
{
|
||||
return std::forward<KeyType>(key);
|
||||
}
|
||||
#endif
|
||||
|
||||
/// @brief erase an element from the object and return the following one
|
||||
/// Not every map returns an iterator from erase(iterator): some containers
|
||||
/// (e.g., Abseil's hash maps) return void to avoid computing a successor
|
||||
@@ -27931,38 +27971,18 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
using copy_scratch_value_t = std::pair<typename object_t::key_type, basic_json>;
|
||||
using copy_scratch_t = std::vector<copy_scratch_value_t, AllocatorType<copy_scratch_value_t>>;
|
||||
|
||||
/// @brief tag selecting the constructor below; used only to build the
|
||||
/// elements of a deep copy (@ref copy_array_level, @ref copy_object_level)
|
||||
struct copy_construct_tag {};
|
||||
|
||||
public:
|
||||
/*!
|
||||
@brief construct a null value whose base class - and, with @ref
|
||||
JSON_DIAGNOSTIC_POSITIONS, positions - are copied from @a src
|
||||
|
||||
Copy-constructing @ref json_base_class_t here, rather than default-
|
||||
constructing the element and assigning its base class afterwards, means
|
||||
that copying a @ref basic_json only ever requires a copy-constructible
|
||||
base class, and never a move-assignable one as well.
|
||||
|
||||
@note this constructor has to be public: @ref copy_array_level and
|
||||
@ref copy_object_level reach it through @ref array_t's or @ref
|
||||
object_t's own emplace_back(), which constructs the element from
|
||||
outside @ref basic_json and so cannot call a private constructor.
|
||||
@ref copy_construct_tag is private, though, and nothing in the
|
||||
public interface hands out a value of it, so outside code can still
|
||||
never name it to call this constructor itself.
|
||||
*/
|
||||
basic_json(copy_construct_tag /*unused*/, const basic_json& src)
|
||||
: json_base_class_t(src)
|
||||
#if JSON_DIAGNOSTIC_POSITIONS
|
||||
, start_position(src.start_position)
|
||||
, end_position(src.end_position)
|
||||
#endif
|
||||
/// @brief copy everything of @a src into @a dst but its type and value
|
||||
static void copy_metadata(const basic_json& src, basic_json& dst)
|
||||
{
|
||||
}
|
||||
// a custom base class is only required to be copy-constructible and
|
||||
// move-assignable, so the copy has to go through a temporary
|
||||
static_cast<json_base_class_t&>(dst) = json_base_class_t(static_cast<const json_base_class_t&>(src));
|
||||
|
||||
private:
|
||||
#if JSON_DIAGNOSTIC_POSITIONS
|
||||
dst.start_position = src.start_position;
|
||||
dst.end_position = src.end_position;
|
||||
#endif
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief copy the value of @a src into @a dst, which must not be structured
|
||||
@@ -28026,11 +28046,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief finish the copy @a dst of @a src that a @ref copy_construct_tag
|
||||
constructor started, other than the children of an object or array
|
||||
@brief copy everything of @a src into the null value @a dst but the children
|
||||
|
||||
@a dst already has @a src's base class and, with @ref
|
||||
JSON_DIAGNOSTIC_POSITIONS, positions; only its value is still missing.
|
||||
Objects and arrays are not copied here; they are appended to @a worklist to
|
||||
be created later by @ref copy_iteratively. Until that happens, @a dst remains
|
||||
a null value, so that a partially built copy can be destroyed at any point
|
||||
@@ -28038,6 +28055,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
*/
|
||||
static void copy_shallow(const basic_json& src, basic_json& dst, copy_worklist_t& worklist)
|
||||
{
|
||||
copy_metadata(src, dst);
|
||||
|
||||
if (src.m_data.m_type == value_t::object || src.m_data.m_type == value_t::array)
|
||||
{
|
||||
// defer: dst stays a null value until its container exists
|
||||
@@ -28058,19 +28077,15 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
{
|
||||
const array_t& src_array = *src.m_data.m_value.array;
|
||||
|
||||
// create all elements up front: growing the array afterwards could
|
||||
// invalidate the pointers that are handed to the worklist; resize()
|
||||
// rather than the fill constructor, because not every array type
|
||||
// provides the latter (e.g., ones without a matching allocator-aware
|
||||
// fill constructor)
|
||||
dst.m_data.m_value.array = create<array_t>();
|
||||
// only now that the array exists may dst stop being a null value
|
||||
dst.m_data.m_type = value_t::array;
|
||||
|
||||
// create every element - its base class already copy-constructed from
|
||||
// its counterpart in src, via the copy_construct_tag constructor -
|
||||
// before any of their addresses are handed to worklist below: growing
|
||||
// the array while that is going on could reallocate it and invalidate
|
||||
// addresses taken from an earlier iteration
|
||||
for (const auto& src_element : src_array)
|
||||
{
|
||||
dst.m_data.m_value.array->emplace_back(copy_construct_tag{}, src_element);
|
||||
}
|
||||
dst.m_data.m_value.array->resize(src_array.size());
|
||||
|
||||
auto dst_it = dst.m_data.m_value.array->begin();
|
||||
for (auto src_it = src_array.cbegin(); src_it != src_array.cend(); ++src_it, ++dst_it)
|
||||
@@ -28088,14 +28103,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
// build the complete key skeleton and hand it to the object's range
|
||||
// constructor: adding the keys one by one would be quadratic for object
|
||||
// types that are backed by a vector, such as nlohmann::ordered_map; each
|
||||
// value's base class is already copy-constructed from its counterpart
|
||||
// in src, via the copy_construct_tag constructor
|
||||
// types that are backed by a vector, such as nlohmann::ordered_map
|
||||
scratch.clear();
|
||||
scratch.reserve(src_object.size());
|
||||
for (const auto& element : src_object)
|
||||
{
|
||||
scratch.emplace_back(element.first, basic_json(copy_construct_tag{}, element.second));
|
||||
scratch.emplace_back(element.first, basic_json());
|
||||
}
|
||||
|
||||
dst.m_data.m_value.object = create<object_t>(std::make_move_iterator(scratch.begin()),
|
||||
@@ -29721,7 +29734,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_THROW(type_error::create(304, detail::concat("cannot use at() with ", type_name()), this));
|
||||
}
|
||||
|
||||
auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
if (it == m_data.m_value.object->end())
|
||||
{
|
||||
JSON_THROW(out_of_range::create(403, detail::concat("key '", string_t(std::forward<KeyType>(key)), "' not found"), this));
|
||||
@@ -29759,7 +29772,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_THROW(type_error::create(304, detail::concat("cannot use at() with ", type_name()), this));
|
||||
}
|
||||
|
||||
auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
if (it == m_data.m_value.object->end())
|
||||
{
|
||||
JSON_THROW(out_of_range::create(403, detail::concat("key '", string_t(std::forward<KeyType>(key)), "' not found"), this));
|
||||
@@ -29902,7 +29915,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
// operator[] only works for objects
|
||||
if (JSON_HEDLEY_LIKELY(is_object()))
|
||||
{
|
||||
auto result = m_data.m_value.object->emplace(std::forward<KeyType>(key), nullptr);
|
||||
auto result = m_data.m_value.object->emplace(lookup_key(std::forward<KeyType>(key)), nullptr);
|
||||
return set_parent(result.first->second);
|
||||
}
|
||||
|
||||
@@ -29918,7 +29931,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
// const operator[] only works for objects
|
||||
if (JSON_HEDLEY_LIKELY(is_object()))
|
||||
{
|
||||
auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
JSON_ASSERT(it != m_data.m_value.object->end());
|
||||
return it->second;
|
||||
}
|
||||
@@ -29928,8 +29941,10 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
private:
|
||||
template<typename KeyType>
|
||||
using is_comparable_with_object_key = detail::is_comparable <
|
||||
object_comparator_t, const typename object_t::key_type&, KeyType >;
|
||||
using is_comparable_with_object_key = std::integral_constant < bool,
|
||||
detail::is_comparable <
|
||||
object_comparator_t, const typename object_t::key_type&, KeyType >::value
|
||||
|| detail::is_string_view_convertible_key_type<basic_json_t, KeyType>::value >;
|
||||
|
||||
template<typename ValueType>
|
||||
using value_return_type = std::conditional <
|
||||
@@ -30316,7 +30331,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_THROW(type_error::create(307, detail::concat("cannot use erase() with ", type_name()), this));
|
||||
}
|
||||
|
||||
const auto it = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
const auto it = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
if (it != m_data.m_value.object->end())
|
||||
{
|
||||
m_data.m_value.object->erase(it);
|
||||
@@ -30343,7 +30358,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
detail::is_usable_as_basic_json_key_type<basic_json_t, KeyType>::value, int> = 0>
|
||||
size_type erase(KeyType && key)
|
||||
{
|
||||
return erase_internal(std::forward<KeyType>(key));
|
||||
return erase_internal(lookup_key(std::forward<KeyType>(key)));
|
||||
}
|
||||
|
||||
/// @brief remove element from a JSON array given an index
|
||||
@@ -30423,7 +30438,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
if (is_object())
|
||||
{
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
}
|
||||
|
||||
return result;
|
||||
@@ -30439,7 +30454,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
if (is_object())
|
||||
{
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(std::forward<KeyType>(key));
|
||||
result.m_it.object_iterator = m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key)));
|
||||
}
|
||||
|
||||
return result;
|
||||
@@ -30462,7 +30477,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
size_type count(KeyType && key) const
|
||||
{
|
||||
// return 0 for all nonobject types
|
||||
return is_object() ? m_data.m_value.object->count(std::forward<KeyType>(key)) : 0;
|
||||
return is_object() ? m_data.m_value.object->count(lookup_key(std::forward<KeyType>(key))) : 0;
|
||||
}
|
||||
|
||||
/// @brief check the existence of an element in a JSON object
|
||||
@@ -30480,7 +30495,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
JSON_HEDLEY_WARN_UNUSED_RESULT
|
||||
bool contains(KeyType && key) const
|
||||
{
|
||||
return is_object() && m_data.m_value.object->find(std::forward<KeyType>(key)) != m_data.m_value.object->end();
|
||||
return is_object() && m_data.m_value.object->find(lookup_key(std::forward<KeyType>(key))) != m_data.m_value.object->end();
|
||||
}
|
||||
|
||||
/// @brief check the existence of an element in a JSON object given a JSON pointer
|
||||
|
||||
@@ -405,73 +405,3 @@ TEST_CASE("JSON Visit Node")
|
||||
);
|
||||
CHECK(expected.empty());
|
||||
}
|
||||
|
||||
// A custom base class with a const member: copy-constructible (initializing a
|
||||
// const member works fine), but not copy-/move-assignable (assigning one does
|
||||
// not). Used to check that copy construction never requires more than that.
|
||||
struct const_member_base
|
||||
{
|
||||
const int id = 7; // NOLINT(misc-non-private-member-variables-in-classes)
|
||||
};
|
||||
|
||||
using json_with_const_base = nlohmann::basic_json <
|
||||
std::map,
|
||||
std::vector,
|
||||
std::string,
|
||||
bool,
|
||||
std::int64_t,
|
||||
std::uint64_t,
|
||||
double,
|
||||
std::allocator,
|
||||
nlohmann::adl_serializer,
|
||||
std::vector<std::uint8_t>,
|
||||
const_member_base
|
||||
>;
|
||||
|
||||
// build an array nested @a depth levels deep, with the innermost value 1;
|
||||
// every level is constructed (never assigned), since const_member_base does
|
||||
// not support assignment
|
||||
static json_with_const_base make_nested_array(std::size_t depth)
|
||||
{
|
||||
if (depth == 0)
|
||||
{
|
||||
return json_with_const_base(1);
|
||||
}
|
||||
return json_with_const_base::array({make_nested_array(depth - 1)});
|
||||
}
|
||||
|
||||
TEST_CASE("Regression test for issue #5674 - copy construction must not require an assignable base class")
|
||||
{
|
||||
SECTION("depth 0")
|
||||
{
|
||||
// as in the original bug report: copy construction only, no assignment
|
||||
const json_with_const_base j = {1, 2};
|
||||
const json_with_const_base copy = j; // NOLINT(performance-unnecessary-copy-initialization)
|
||||
|
||||
CHECK(copy.size() == 2);
|
||||
CHECK(copy.id == 7);
|
||||
}
|
||||
|
||||
SECTION("nested deeper than the copy constructor's descent bound")
|
||||
{
|
||||
// beyond nesting_depth_limit() (128) levels, the copy constructor
|
||||
// copies without the call stack (copy_iteratively / copy_array_level),
|
||||
// which used to assign the base class of every element it created
|
||||
const std::size_t depth = 300;
|
||||
|
||||
const json_with_const_base j = make_nested_array(depth);
|
||||
const json_with_const_base copy = j; // NOLINT(performance-unnecessary-copy-initialization)
|
||||
|
||||
const json_with_const_base* c = ©
|
||||
for (std::size_t level = 0; level <= depth; ++level)
|
||||
{
|
||||
CAPTURE(level)
|
||||
REQUIRE(c->id == 7);
|
||||
if (level < depth)
|
||||
{
|
||||
c = &c->at(0);
|
||||
}
|
||||
}
|
||||
CHECK(*c == 1);
|
||||
}
|
||||
}
|
||||
|
||||
@@ -1973,4 +1973,115 @@ TEST_CASE("operator[] with user-defined std::string_view-convertible types")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
TEST_CASE("keys convertible to std::string_view work with all lookup functions (regression test for #5663)")
|
||||
{
|
||||
// a key type convertible only to std::string_view: the case #4958 added
|
||||
// support for, but only the non-const operator[] compiled with it
|
||||
struct ViewKey
|
||||
{
|
||||
operator std::string_view() const
|
||||
{
|
||||
return "a";
|
||||
}
|
||||
};
|
||||
|
||||
// a key type convertible to both std::string and std::string_view: with
|
||||
// 3.12.0, such a key worked with at, the const operator[], find, count and
|
||||
// contains via the conversion to std::string; #4958 made the KeyType&&
|
||||
// templates win overload resolution for it instead, and those then failed
|
||||
struct DualKey
|
||||
{
|
||||
operator std::string() const
|
||||
{
|
||||
return "a";
|
||||
}
|
||||
operator std::string_view() const
|
||||
{
|
||||
return "a";
|
||||
}
|
||||
};
|
||||
|
||||
SECTION("nlohmann::json")
|
||||
{
|
||||
using json = nlohmann::json;
|
||||
|
||||
SECTION("ViewKey")
|
||||
{
|
||||
json j = {{"a", 1}};
|
||||
const json& cj = j;
|
||||
|
||||
CHECK(j[ViewKey{}] == 1);
|
||||
CHECK(cj[ViewKey{}] == 1);
|
||||
CHECK(j.at(ViewKey{}) == 1);
|
||||
CHECK(cj.at(ViewKey{}) == 1);
|
||||
CHECK(j.find(ViewKey{}) != j.end());
|
||||
CHECK(cj.find(ViewKey{}) != cj.end());
|
||||
CHECK(j.count(ViewKey{}) == 1);
|
||||
CHECK(j.contains(ViewKey{}));
|
||||
CHECK(j.value(ViewKey{}, 0) == 1);
|
||||
CHECK(j.erase(ViewKey{}) == 1);
|
||||
CHECK(!j.contains("a"));
|
||||
}
|
||||
|
||||
SECTION("DualKey")
|
||||
{
|
||||
json j = {{"a", 1}};
|
||||
const json& cj = j;
|
||||
|
||||
CHECK(j[DualKey{}] == 1);
|
||||
CHECK(cj[DualKey{}] == 1);
|
||||
CHECK(j.at(DualKey{}) == 1);
|
||||
CHECK(cj.at(DualKey{}) == 1);
|
||||
CHECK(j.find(DualKey{}) != j.end());
|
||||
CHECK(cj.find(DualKey{}) != cj.end());
|
||||
CHECK(j.count(DualKey{}) == 1);
|
||||
CHECK(j.contains(DualKey{}));
|
||||
CHECK(j.value(DualKey{}, 0) == 1);
|
||||
CHECK(j.erase(DualKey{}) == 1);
|
||||
CHECK(!j.contains("a"));
|
||||
}
|
||||
}
|
||||
|
||||
SECTION("nlohmann::ordered_json")
|
||||
{
|
||||
using ordered_json = nlohmann::ordered_json;
|
||||
|
||||
SECTION("ViewKey")
|
||||
{
|
||||
ordered_json j = {{"a", 1}};
|
||||
const ordered_json& cj = j;
|
||||
|
||||
CHECK(j[ViewKey{}] == 1);
|
||||
CHECK(cj[ViewKey{}] == 1);
|
||||
CHECK(j.at(ViewKey{}) == 1);
|
||||
CHECK(cj.at(ViewKey{}) == 1);
|
||||
CHECK(j.find(ViewKey{}) != j.end());
|
||||
CHECK(cj.find(ViewKey{}) != cj.end());
|
||||
CHECK(j.count(ViewKey{}) == 1);
|
||||
CHECK(j.contains(ViewKey{}));
|
||||
CHECK(j.value(ViewKey{}, 0) == 1);
|
||||
CHECK(j.erase(ViewKey{}) == 1);
|
||||
CHECK(!j.contains("a"));
|
||||
}
|
||||
|
||||
SECTION("DualKey")
|
||||
{
|
||||
ordered_json j = {{"a", 1}};
|
||||
const ordered_json& cj = j;
|
||||
|
||||
CHECK(j[DualKey{}] == 1);
|
||||
CHECK(cj[DualKey{}] == 1);
|
||||
CHECK(j.at(DualKey{}) == 1);
|
||||
CHECK(cj.at(DualKey{}) == 1);
|
||||
CHECK(j.find(DualKey{}) != j.end());
|
||||
CHECK(cj.find(DualKey{}) != cj.end());
|
||||
CHECK(j.count(DualKey{}) == 1);
|
||||
CHECK(j.contains(DualKey{}));
|
||||
CHECK(j.value(DualKey{}, 0) == 1);
|
||||
CHECK(j.erase(DualKey{}) == 1);
|
||||
CHECK(!j.contains("a"));
|
||||
}
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
Reference in New Issue
Block a user