Allow custom base class as node customization point (#3110)
Co-authored-by: Niels Lohmann <niels.lohmann@gmail.com> Co-authored-by: Florian Albrechtskirchinger <falbrechtskirchinger@gmail.com> Co-authored-by: barcode <barcode@example.com>
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88
docs/examples/json_base_class_t.cpp
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88
docs/examples/json_base_class_t.cpp
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@ -0,0 +1,88 @@
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#include <iostream>
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#include <nlohmann/json.hpp>
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class visitor_adaptor_with_metadata
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{
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public:
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template <class Fnc>
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void visit(const Fnc& fnc) const;
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int metadata = 42;
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private:
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template <class Ptr, class Fnc>
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void do_visit(const Ptr& ptr, const Fnc& fnc) const;
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};
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using json = nlohmann::basic_json <
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std::map,
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std::vector,
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std::string,
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bool,
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std::int64_t,
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std::uint64_t,
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double,
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std::allocator,
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nlohmann::adl_serializer,
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std::vector<std::uint8_t>,
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visitor_adaptor_with_metadata
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>;
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template <class Fnc>
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void visitor_adaptor_with_metadata::visit(const Fnc& fnc) const
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{
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do_visit(json::json_pointer{}, fnc);
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}
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template <class Ptr, class Fnc>
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void visitor_adaptor_with_metadata::do_visit(const Ptr& ptr, const Fnc& fnc) const
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{
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using value_t = nlohmann::detail::value_t;
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const json& j = *static_cast<const json*>(this);
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switch (j.type())
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{
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case value_t::object:
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fnc(ptr, j);
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for (const auto& entry : j.items())
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{
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entry.value().do_visit(ptr / entry.key(), fnc);
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}
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break;
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case value_t::array:
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fnc(ptr, j);
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for (std::size_t i = 0; i < j.size(); ++i)
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{
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j.at(i).do_visit(ptr / std::to_string(i), fnc);
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}
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break;
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case value_t::null:
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case value_t::string:
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case value_t::boolean:
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case value_t::number_integer:
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case value_t::number_unsigned:
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case value_t::number_float:
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case value_t::binary:
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fnc(ptr, j);
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break;
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case value_t::discarded:
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default:
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break;
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}
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}
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int main()
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{
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// create a json object
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json j;
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j["null"];
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j["object"]["uint"] = 1U;
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j["object"].metadata = 21;
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// visit and output
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j.visit(
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[&](const json::json_pointer & p,
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const json & j)
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{
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std::cout << (p.empty() ? std::string{"/"} : p.to_string())
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<< " - metadata = " << j.metadata << " -> " << j.dump() << '\n';
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});
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}
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4
docs/examples/json_base_class_t.output
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4
docs/examples/json_base_class_t.output
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/ - metadata = 42 -> {"null":null,"object":{"uint":1}}
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/null - metadata = 42 -> null
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/object - metadata = 21 -> {"uint":1}
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/object/uint - metadata = 42 -> 1
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@ -13,7 +13,8 @@ template<
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class NumberFloatType = double,
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template<typename U> class AllocatorType = std::allocator,
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template<typename T, typename SFINAE = void> class JSONSerializer = adl_serializer,
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class BinaryType = std::vector<std::uint8_t>
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class BinaryType = std::vector<std::uint8_t,
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class CustomBaseClass = void>
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>
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class basic_json;
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```
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@ -32,6 +33,7 @@ class basic_json;
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| `AllocatorType` | type of the allocator to use | |
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| `JSONSerializer` | the serializer to resolve internal calls to `to_json()` and `from_json()` | [`json_serializer`](json_serializer.md) |
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| `BinaryType` | type for binary arrays | [`binary_t`](binary_t.md) |
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| `CustomBaseClass` | extension point for user code | [`json_base_class_t`](json_base_class_t.md) |
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## Specializations
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docs/mkdocs/docs/api/basic_json/json_base_class_t.md
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44
docs/mkdocs/docs/api/basic_json/json_base_class_t.md
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# <small>nlohmann::basic_json::</small>json_base_class_t
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```cpp
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using json_base_class_t = detail::json_base_class<CustomBaseClass>;
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```
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The base class used to inject custom functionality into each instance of `basic_json`.
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Examples of such functionality might be metadata, additional member functions (e.g., visitors), or other application-specific code.
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## Template parameters
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`CustomBaseClass`
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: the base class to be added to `basic_json`
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## Notes
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#### Default type
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The default value for `CustomBaseClass` is `void`. In this case an [empty base class](https://en.cppreference.com/w/cpp/language/ebo) is used and no additional functionality is injected.
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#### Limitations
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The type `CustomBaseClass` has to be a default-constructible class.
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`basic_json` only supports copy/move construction/assignment if `CustomBaseClass` does so as well.
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## Examples
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??? example
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The following code shows how to inject custom data and methods for each node.
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```cpp
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--8<-- "examples/json_base_class_t.cpp"
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```
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Output:
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```json
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--8<-- "examples/json_base_class_t.output"
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```
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## Version history
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- Added in version 3.12.0.
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@ -141,6 +141,7 @@ nav:
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- 'is_string': api/basic_json/is_string.md
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- 'is_structured': api/basic_json/is_structured.md
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- 'items': api/basic_json/items.md
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- 'json_base_class_t': api/basic_json/json_base_class_t.md
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- 'json_serializer': api/basic_json/json_serializer.md
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- 'max_size': api/basic_json/max_size.md
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- 'meta': api/basic_json/meta.md
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include/nlohmann/detail/json_custom_base_class.hpp
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include/nlohmann/detail/json_custom_base_class.hpp
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#pragma once
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#include <type_traits> // conditional, is_same
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#include <nlohmann/detail/abi_macros.hpp>
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NLOHMANN_JSON_NAMESPACE_BEGIN
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namespace detail
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{
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/*!
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@brief Default base class of the @ref basic_json class.
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So that the correct implementations of the copy / move ctors / assign operators
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of @ref basic_json do not require complex case distinctions
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(no base class / custom base class used as customization point),
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@ref basic_json always has a base class.
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By default, this class is used because it is empty and thus has no effect
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on the behavior of @ref basic_json.
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*/
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struct json_default_base {};
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template<class T>
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using json_base_class = typename std::conditional <
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std::is_same<T, void>::value,
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json_default_base,
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T
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>::type;
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} // namespace detail
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NLOHMANN_JSON_NAMESPACE_END
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@ -240,12 +240,13 @@
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class NumberUnsignedType, class NumberFloatType, \
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template<typename> class AllocatorType, \
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template<typename, typename = void> class JSONSerializer, \
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class BinaryType>
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class BinaryType, \
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class CustomBaseClass>
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#define NLOHMANN_BASIC_JSON_TPL \
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basic_json<ObjectType, ArrayType, StringType, BooleanType, \
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NumberIntegerType, NumberUnsignedType, NumberFloatType, \
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AllocatorType, JSONSerializer, BinaryType>
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AllocatorType, JSONSerializer, BinaryType, CustomBaseClass>
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// Macros to simplify conversion from/to types
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@ -47,6 +47,7 @@
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#include <nlohmann/detail/iterators/iteration_proxy.hpp>
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#include <nlohmann/detail/iterators/json_reverse_iterator.hpp>
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#include <nlohmann/detail/iterators/primitive_iterator.hpp>
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#include <nlohmann/detail/json_custom_base_class.hpp>
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#include <nlohmann/detail/json_pointer.hpp>
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#include <nlohmann/detail/json_ref.hpp>
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#include <nlohmann/detail/macro_scope.hpp>
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@ -93,6 +94,7 @@ The invariants are checked by member function assert_invariant().
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*/
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NLOHMANN_BASIC_JSON_TPL_DECLARATION
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class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-special-member-functions)
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: public ::nlohmann::detail::json_base_class<CustomBaseClass>
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{
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private:
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template<detail::value_t> friend struct detail::external_constructor;
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@ -119,6 +121,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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/// workaround type for MSVC
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using basic_json_t = NLOHMANN_BASIC_JSON_TPL;
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using json_base_class_t = ::nlohmann::detail::json_base_class<CustomBaseClass>;
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JSON_PRIVATE_UNLESS_TESTED:
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// convenience aliases for types residing in namespace detail;
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@ -1132,7 +1135,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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/// @brief copy constructor
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/// @sa https://json.nlohmann.me/api/basic_json/basic_json/
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basic_json(const basic_json& other)
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: m_type(other.m_type)
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: json_base_class_t(other),
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m_type(other.m_type)
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{
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// check of passed value is valid
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other.assert_invariant();
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@ -1200,11 +1204,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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/// @brief move constructor
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/// @sa https://json.nlohmann.me/api/basic_json/basic_json/
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basic_json(basic_json&& other) noexcept
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: m_type(std::move(other.m_type)),
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: json_base_class_t(std::move(other)),
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m_type(std::move(other.m_type)),
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m_value(std::move(other.m_value))
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{
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// check that passed value is valid
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other.assert_invariant(false);
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other.assert_invariant(false); // NOLINT(bugprone-use-after-move,hicpp-invalid-access-moved)
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// invalidate payload
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other.m_type = value_t::null;
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@ -1220,7 +1225,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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std::is_nothrow_move_constructible<value_t>::value&&
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std::is_nothrow_move_assignable<value_t>::value&&
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std::is_nothrow_move_constructible<json_value>::value&&
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std::is_nothrow_move_assignable<json_value>::value
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std::is_nothrow_move_assignable<json_value>::value&&
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std::is_nothrow_move_assignable<json_base_class_t>::value
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)
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{
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// check that passed value is valid
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@ -1229,6 +1235,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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using std::swap;
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swap(m_type, other.m_type);
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swap(m_value, other.m_value);
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json_base_class_t::operator=(std::move(other));
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set_parents();
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assert_invariant();
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@ -46,7 +46,8 @@ template<template<typename U, typename V, typename... Args> class ObjectType =
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template<typename U> class AllocatorType = std::allocator,
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template<typename T, typename SFINAE = void> class JSONSerializer =
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adl_serializer,
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class BinaryType = std::vector<std::uint8_t>>
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class BinaryType = std::vector<std::uint8_t>, // cppcheck-suppress syntaxError
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class CustomBaseClass = void>
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class basic_json;
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/// @brief JSON Pointer defines a string syntax for identifying a specific value within a JSON document
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@ -2590,12 +2590,13 @@ JSON_HEDLEY_DIAGNOSTIC_POP
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class NumberUnsignedType, class NumberFloatType, \
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template<typename> class AllocatorType, \
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template<typename, typename = void> class JSONSerializer, \
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class BinaryType>
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class BinaryType, \
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class CustomBaseClass>
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#define NLOHMANN_BASIC_JSON_TPL \
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basic_json<ObjectType, ArrayType, StringType, BooleanType, \
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NumberIntegerType, NumberUnsignedType, NumberFloatType, \
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AllocatorType, JSONSerializer, BinaryType>
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AllocatorType, JSONSerializer, BinaryType, CustomBaseClass>
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// Macros to simplify conversion from/to types
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@ -3389,7 +3390,8 @@ NLOHMANN_JSON_NAMESPACE_END
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template<typename U> class AllocatorType = std::allocator,
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template<typename T, typename SFINAE = void> class JSONSerializer =
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adl_serializer,
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class BinaryType = std::vector<std::uint8_t>>
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class BinaryType = std::vector<std::uint8_t>, // cppcheck-suppress syntaxError
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class CustomBaseClass = void>
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class basic_json;
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/// @brief JSON Pointer defines a string syntax for identifying a specific value within a JSON document
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@ -13673,6 +13675,40 @@ NLOHMANN_JSON_NAMESPACE_END
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// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
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// #include <nlohmann/detail/json_custom_base_class.hpp>
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#include <type_traits> // conditional, is_same
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// #include <nlohmann/detail/abi_macros.hpp>
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NLOHMANN_JSON_NAMESPACE_BEGIN
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namespace detail
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{
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/*!
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@brief Default base class of the @ref basic_json class.
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So that the correct implementations of the copy / move ctors / assign operators
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of @ref basic_json do not require complex case distinctions
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(no base class / custom base class used as customization point),
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@ref basic_json always has a base class.
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By default, this class is used because it is empty and thus has no effect
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on the behavior of @ref basic_json.
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*/
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struct json_default_base {};
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template<class T>
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using json_base_class = typename std::conditional <
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std::is_same<T, void>::value,
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json_default_base,
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T
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>::type;
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} // namespace detail
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NLOHMANN_JSON_NAMESPACE_END
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// #include <nlohmann/detail/json_pointer.hpp>
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// __ _____ _____ _____
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// __| | __| | | | JSON for Modern C++
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@ -19271,6 +19307,7 @@ The invariants are checked by member function assert_invariant().
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*/
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NLOHMANN_BASIC_JSON_TPL_DECLARATION
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class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-special-member-functions)
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: public ::nlohmann::detail::json_base_class<CustomBaseClass>
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{
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private:
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template<detail::value_t> friend struct detail::external_constructor;
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@ -19297,6 +19334,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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/// workaround type for MSVC
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using basic_json_t = NLOHMANN_BASIC_JSON_TPL;
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using json_base_class_t = ::nlohmann::detail::json_base_class<CustomBaseClass>;
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JSON_PRIVATE_UNLESS_TESTED:
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// convenience aliases for types residing in namespace detail;
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@ -20310,7 +20348,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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/// @brief copy constructor
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/// @sa https://json.nlohmann.me/api/basic_json/basic_json/
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basic_json(const basic_json& other)
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: m_type(other.m_type)
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: json_base_class_t(other),
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m_type(other.m_type)
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{
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// check of passed value is valid
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other.assert_invariant();
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@ -20378,11 +20417,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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/// @brief move constructor
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/// @sa https://json.nlohmann.me/api/basic_json/basic_json/
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basic_json(basic_json&& other) noexcept
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: m_type(std::move(other.m_type)),
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: json_base_class_t(std::move(other)),
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m_type(std::move(other.m_type)),
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m_value(std::move(other.m_value))
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{
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// check that passed value is valid
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other.assert_invariant(false);
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other.assert_invariant(false); // NOLINT(bugprone-use-after-move,hicpp-invalid-access-moved)
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// invalidate payload
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other.m_type = value_t::null;
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@ -20398,7 +20438,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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std::is_nothrow_move_constructible<value_t>::value&&
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std::is_nothrow_move_assignable<value_t>::value&&
|
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std::is_nothrow_move_constructible<json_value>::value&&
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std::is_nothrow_move_assignable<json_value>::value
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std::is_nothrow_move_assignable<json_value>::value&&
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std::is_nothrow_move_assignable<json_base_class_t>::value
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)
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{
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// check that passed value is valid
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@ -20407,6 +20448,7 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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using std::swap;
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swap(m_type, other.m_type);
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swap(m_value, other.m_value);
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json_base_class_t::operator=(std::move(other));
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set_parents();
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assert_invariant();
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|
@ -147,7 +147,8 @@ template<template<typename U, typename V, typename... Args> class ObjectType =
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template<typename U> class AllocatorType = std::allocator,
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template<typename T, typename SFINAE = void> class JSONSerializer =
|
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adl_serializer,
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class BinaryType = std::vector<std::uint8_t>>
|
||||
class BinaryType = std::vector<std::uint8_t>, // cppcheck-suppress syntaxError
|
||||
class CustomBaseClass = void>
|
||||
class basic_json;
|
||||
|
||||
/// @brief JSON Pointer defines a string syntax for identifying a specific value within a JSON document
|
||||
|
357
tests/src/unit-custom-base-class.cpp
Normal file
357
tests/src/unit-custom-base-class.cpp
Normal file
@ -0,0 +1,357 @@
|
||||
/*
|
||||
__ _____ _____ _____
|
||||
__| | __| | | | JSON for Modern C++ (test suite)
|
||||
| | |__ | | | | | | version 3.10.2
|
||||
|_____|_____|_____|_|___| https://github.com/nlohmann/json
|
||||
|
||||
Licensed under the MIT License <http://opensource.org/licenses/MIT>.
|
||||
SPDX-License-Identifier: MIT
|
||||
Copyright (c) 2013-2019 Niels Lohmann <http://nlohmann.me>.
|
||||
|
||||
Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
of this software and associated documentation files (the "Software"), to deal
|
||||
in the Software without restriction, including without limitation the rights
|
||||
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
copies of the Software, and to permit persons to whom the Software is
|
||||
furnished to do so, subject to the following conditions:
|
||||
|
||||
The above copyright notice and this permission notice shall be included in all
|
||||
copies or substantial portions of the Software.
|
||||
|
||||
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||||
SOFTWARE.
|
||||
*/
|
||||
|
||||
#include <set>
|
||||
#include <sstream>
|
||||
#include <string>
|
||||
|
||||
#include "doctest_compatibility.h"
|
||||
|
||||
#include <nlohmann/json.hpp>
|
||||
|
||||
// Test extending nlohmann::json by using a custom base class.
|
||||
// Add some metadata to each node and test the behaviour of copy / move
|
||||
template<class MetaDataType>
|
||||
class json_metadata
|
||||
{
|
||||
public:
|
||||
using metadata_t = MetaDataType;
|
||||
metadata_t& metadata()
|
||||
{
|
||||
return m_metadata;
|
||||
}
|
||||
const metadata_t& metadata() const
|
||||
{
|
||||
return m_metadata;
|
||||
}
|
||||
private:
|
||||
metadata_t m_metadata = {};
|
||||
};
|
||||
|
||||
template<class T>
|
||||
using json_with_metadata =
|
||||
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>,
|
||||
json_metadata<T>
|
||||
>;
|
||||
|
||||
TEST_CASE("JSON Node Metadata")
|
||||
{
|
||||
SECTION("type int")
|
||||
{
|
||||
using json = json_with_metadata<int>;
|
||||
json null;
|
||||
auto obj = json::object();
|
||||
auto array = json::array();
|
||||
|
||||
null.metadata() = 1;
|
||||
obj.metadata() = 2;
|
||||
array.metadata() = 3;
|
||||
auto copy = array;
|
||||
|
||||
CHECK(null.metadata() == 1);
|
||||
CHECK(obj.metadata() == 2);
|
||||
CHECK(array.metadata() == 3);
|
||||
CHECK(copy.metadata() == 3);
|
||||
}
|
||||
SECTION("type vector<int>")
|
||||
{
|
||||
using json = json_with_metadata<std::vector<int>>;
|
||||
json value;
|
||||
value.metadata().emplace_back(1);
|
||||
auto copy = value;
|
||||
value.metadata().emplace_back(2);
|
||||
|
||||
CHECK(copy.metadata().size() == 1);
|
||||
CHECK(copy.metadata().at(0) == 1);
|
||||
CHECK(value.metadata().size() == 2);
|
||||
CHECK(value.metadata().at(0) == 1);
|
||||
CHECK(value.metadata().at(1) == 2);
|
||||
}
|
||||
SECTION("copy ctor")
|
||||
{
|
||||
using json = json_with_metadata<std::vector<int>>;
|
||||
json value;
|
||||
value.metadata().emplace_back(1);
|
||||
value.metadata().emplace_back(2);
|
||||
|
||||
json copy = value;
|
||||
|
||||
CHECK(copy.metadata().size() == 2);
|
||||
CHECK(copy.metadata().at(0) == 1);
|
||||
CHECK(copy.metadata().at(1) == 2);
|
||||
CHECK(value.metadata().size() == 2);
|
||||
CHECK(value.metadata().at(0) == 1);
|
||||
CHECK(value.metadata().at(1) == 2);
|
||||
|
||||
value.metadata().clear();
|
||||
CHECK(copy.metadata().size() == 2);
|
||||
CHECK(value.metadata().size() == 0);
|
||||
}
|
||||
SECTION("move ctor")
|
||||
{
|
||||
using json = json_with_metadata<std::vector<int>>;
|
||||
json value;
|
||||
value.metadata().emplace_back(1);
|
||||
value.metadata().emplace_back(2);
|
||||
|
||||
const json moved = std::move(value);
|
||||
|
||||
CHECK(moved.metadata().size() == 2);
|
||||
CHECK(moved.metadata().at(0) == 1);
|
||||
CHECK(moved.metadata().at(1) == 2);
|
||||
}
|
||||
SECTION("move assign")
|
||||
{
|
||||
using json = json_with_metadata<std::vector<int>>;
|
||||
json value;
|
||||
value.metadata().emplace_back(1);
|
||||
value.metadata().emplace_back(2);
|
||||
|
||||
json moved;
|
||||
moved = std::move(value);
|
||||
|
||||
CHECK(moved.metadata().size() == 2);
|
||||
CHECK(moved.metadata().at(0) == 1);
|
||||
CHECK(moved.metadata().at(1) == 2);
|
||||
}
|
||||
SECTION("copy assign")
|
||||
{
|
||||
using json = json_with_metadata<std::vector<int>>;
|
||||
json value;
|
||||
value.metadata().emplace_back(1);
|
||||
value.metadata().emplace_back(2);
|
||||
|
||||
json copy;
|
||||
copy = value;
|
||||
|
||||
CHECK(copy.metadata().size() == 2);
|
||||
CHECK(copy.metadata().at(0) == 1);
|
||||
CHECK(copy.metadata().at(1) == 2);
|
||||
CHECK(value.metadata().size() == 2);
|
||||
CHECK(value.metadata().at(0) == 1);
|
||||
CHECK(value.metadata().at(1) == 2);
|
||||
|
||||
value.metadata().clear();
|
||||
CHECK(copy.metadata().size() == 2);
|
||||
CHECK(value.metadata().size() == 0);
|
||||
}
|
||||
SECTION("type unique_ptr<int>")
|
||||
{
|
||||
using json = json_with_metadata<std::unique_ptr<int>>;
|
||||
json value;
|
||||
value.metadata().reset(new int(42)); // NOLINT(cppcoreguidelines-owning-memory)
|
||||
auto moved = std::move(value);
|
||||
|
||||
CHECK(moved.metadata() != nullptr);
|
||||
CHECK(*moved.metadata() == 42);
|
||||
}
|
||||
SECTION("type vector<int> in json array")
|
||||
{
|
||||
using json = json_with_metadata<std::vector<int>>;
|
||||
json value;
|
||||
value.metadata().emplace_back(1);
|
||||
value.metadata().emplace_back(2);
|
||||
|
||||
json array(10, value);
|
||||
|
||||
CHECK(value.metadata().size() == 2);
|
||||
CHECK(value.metadata().at(0) == 1);
|
||||
CHECK(value.metadata().at(1) == 2);
|
||||
|
||||
for (const auto& val : array)
|
||||
{
|
||||
CHECK(val.metadata().size() == 2);
|
||||
CHECK(val.metadata().at(0) == 1);
|
||||
CHECK(val.metadata().at(1) == 2);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Test extending nlohmann::json by using a custom base class.
|
||||
// Add a custom member function template iterating over the whole json tree.
|
||||
class visitor_adaptor
|
||||
{
|
||||
public:
|
||||
template <class Fnc>
|
||||
void visit(const Fnc& fnc) const;
|
||||
private:
|
||||
template <class Ptr, class Fnc>
|
||||
void do_visit(const Ptr& ptr, const Fnc& fnc) const;
|
||||
};
|
||||
|
||||
using json_with_visitor_t = 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>,
|
||||
visitor_adaptor
|
||||
>;
|
||||
|
||||
|
||||
template <class Fnc>
|
||||
void visitor_adaptor::visit(const Fnc& fnc) const
|
||||
{
|
||||
do_visit(json_with_visitor_t::json_pointer{}, fnc);
|
||||
}
|
||||
|
||||
template <class Ptr, class Fnc>
|
||||
void visitor_adaptor::do_visit(const Ptr& ptr, const Fnc& fnc) const
|
||||
{
|
||||
using value_t = nlohmann::detail::value_t;
|
||||
const json_with_visitor_t& json = *static_cast<const json_with_visitor_t*>(this);
|
||||
switch (json.type())
|
||||
{
|
||||
case value_t::object:
|
||||
for (const auto& entry : json.items())
|
||||
{
|
||||
entry.value().do_visit(ptr / entry.key(), fnc);
|
||||
}
|
||||
break;
|
||||
case value_t::array:
|
||||
for (std::size_t i = 0; i < json.size(); ++i)
|
||||
{
|
||||
json.at(i).do_visit(ptr / std::to_string(i), fnc);
|
||||
}
|
||||
break;
|
||||
case value_t::discarded:
|
||||
break;
|
||||
case value_t::null:
|
||||
case value_t::string:
|
||||
case value_t::boolean:
|
||||
case value_t::number_integer:
|
||||
case value_t::number_unsigned:
|
||||
case value_t::number_float:
|
||||
case value_t::binary:
|
||||
default:
|
||||
fnc(ptr, json);
|
||||
}
|
||||
}
|
||||
|
||||
TEST_CASE("JSON Visit Node")
|
||||
{
|
||||
json_with_visitor_t json;
|
||||
json["null"];
|
||||
json["int"] = -1;
|
||||
json["uint"] = 1U;
|
||||
json["float"] = 1.0;
|
||||
json["boolean"] = true;
|
||||
json["string"] = "string";
|
||||
json["array"].push_back(0);
|
||||
json["array"].push_back(1);
|
||||
json["array"].push_back(json);
|
||||
|
||||
std::set<std::string> expected
|
||||
{
|
||||
"/null - null - null",
|
||||
"/int - number_integer - -1",
|
||||
"/uint - number_unsigned - 1",
|
||||
"/float - number_float - 1.0",
|
||||
"/boolean - boolean - true",
|
||||
"/string - string - \"string\"",
|
||||
"/array/0 - number_integer - 0",
|
||||
"/array/1 - number_integer - 1",
|
||||
|
||||
"/array/2/null - null - null",
|
||||
"/array/2/int - number_integer - -1",
|
||||
"/array/2/uint - number_unsigned - 1",
|
||||
"/array/2/float - number_float - 1.0",
|
||||
"/array/2/boolean - boolean - true",
|
||||
"/array/2/string - string - \"string\"",
|
||||
"/array/2/array/0 - number_integer - 0",
|
||||
"/array/2/array/1 - number_integer - 1"
|
||||
};
|
||||
|
||||
json.visit(
|
||||
[&](const json_with_visitor_t::json_pointer & p,
|
||||
const json_with_visitor_t& j)
|
||||
{
|
||||
std::stringstream str;
|
||||
str << p.to_string() << " - " ;
|
||||
using value_t = nlohmann::detail::value_t;
|
||||
switch (j.type())
|
||||
{
|
||||
case value_t::object:
|
||||
str << "object";
|
||||
break;
|
||||
case value_t::array:
|
||||
str << "array";
|
||||
break;
|
||||
case value_t::discarded:
|
||||
str << "discarded";
|
||||
break;
|
||||
case value_t::null:
|
||||
str << "null";
|
||||
break;
|
||||
case value_t::string:
|
||||
str << "string";
|
||||
break;
|
||||
case value_t::boolean:
|
||||
str << "boolean";
|
||||
break;
|
||||
case value_t::number_integer:
|
||||
str << "number_integer";
|
||||
break;
|
||||
case value_t::number_unsigned:
|
||||
str << "number_unsigned";
|
||||
break;
|
||||
case value_t::number_float:
|
||||
str << "number_float";
|
||||
break;
|
||||
case value_t::binary:
|
||||
str << "binary";
|
||||
break;
|
||||
default:
|
||||
str << "error";
|
||||
break;
|
||||
}
|
||||
str << " - " << j.dump();
|
||||
CHECK(json.at(p) == j);
|
||||
INFO(str.str());
|
||||
CHECK(expected.count(str.str()) == 1);
|
||||
expected.erase(str.str());
|
||||
}
|
||||
);
|
||||
CHECK(expected.empty());
|
||||
}
|
Loading…
Reference in New Issue
Block a user