MushMachine/external/json/include/nlohmann/detail/json_pointer.hpp

901 lines
32 KiB
C++

// __ _____ _____ _____
// __| | __| | | | JSON for Modern C++
// | | |__ | | | | | | version 3.11.1
// |_____|_____|_____|_|___| https://github.com/nlohmann/json
//
// SPDX-FileCopyrightText: 2013-2022 Niels Lohmann <https://nlohmann.me>
// SPDX-License-Identifier: MIT
#pragma once
#include <algorithm> // all_of
#include <cctype> // isdigit
#include <cerrno> // errno, ERANGE
#include <cstdlib> // strtoull
#ifndef JSON_NO_IO
#include <iosfwd> // ostream
#endif // JSON_NO_IO
#include <limits> // max
#include <numeric> // accumulate
#include <string> // string
#include <utility> // move
#include <vector> // vector
#include <nlohmann/detail/exceptions.hpp>
#include <nlohmann/detail/macro_scope.hpp>
#include <nlohmann/detail/string_concat.hpp>
#include <nlohmann/detail/string_escape.hpp>
#include <nlohmann/detail/value_t.hpp>
NLOHMANN_JSON_NAMESPACE_BEGIN
/// @brief JSON Pointer defines a string syntax for identifying a specific value within a JSON document
/// @sa https://json.nlohmann.me/api/json_pointer/
template<typename RefStringType>
class json_pointer
{
// allow basic_json to access private members
NLOHMANN_BASIC_JSON_TPL_DECLARATION
friend class basic_json;
template<typename>
friend class json_pointer;
template<typename T>
struct string_t_helper
{
using type = T;
};
NLOHMANN_BASIC_JSON_TPL_DECLARATION
struct string_t_helper<NLOHMANN_BASIC_JSON_TPL>
{
using type = StringType;
};
public:
// for backwards compatibility accept BasicJsonType
using string_t = typename string_t_helper<RefStringType>::type;
/// @brief create JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/json_pointer/
explicit json_pointer(const string_t& s = "")
: reference_tokens(split(s))
{}
/// @brief return a string representation of the JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/to_string/
string_t to_string() const
{
return std::accumulate(reference_tokens.begin(), reference_tokens.end(),
string_t{},
[](const string_t& a, const string_t& b)
{
return detail::concat(a, '/', detail::escape(b));
});
}
/// @brief return a string representation of the JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_string/
JSON_HEDLEY_DEPRECATED_FOR(3.11.0, to_string())
operator string_t() const
{
return to_string();
}
#ifndef JSON_NO_IO
/// @brief write string representation of the JSON pointer to stream
/// @sa https://json.nlohmann.me/api/basic_json/operator_ltlt/
friend std::ostream& operator<<(std::ostream& o, const json_pointer& ptr)
{
o << ptr.to_string();
return o;
}
#endif
/// @brief append another JSON pointer at the end of this JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_slasheq/
json_pointer& operator/=(const json_pointer& ptr)
{
reference_tokens.insert(reference_tokens.end(),
ptr.reference_tokens.begin(),
ptr.reference_tokens.end());
return *this;
}
/// @brief append an unescaped reference token at the end of this JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_slasheq/
json_pointer& operator/=(string_t token)
{
push_back(std::move(token));
return *this;
}
/// @brief append an array index at the end of this JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_slasheq/
json_pointer& operator/=(std::size_t array_idx)
{
return *this /= std::to_string(array_idx);
}
/// @brief create a new JSON pointer by appending the right JSON pointer at the end of the left JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_slash/
friend json_pointer operator/(const json_pointer& lhs,
const json_pointer& rhs)
{
return json_pointer(lhs) /= rhs;
}
/// @brief create a new JSON pointer by appending the unescaped token at the end of the JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_slash/
friend json_pointer operator/(const json_pointer& lhs, string_t token) // NOLINT(performance-unnecessary-value-param)
{
return json_pointer(lhs) /= std::move(token);
}
/// @brief create a new JSON pointer by appending the array-index-token at the end of the JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/operator_slash/
friend json_pointer operator/(const json_pointer& lhs, std::size_t array_idx)
{
return json_pointer(lhs) /= array_idx;
}
/// @brief returns the parent of this JSON pointer
/// @sa https://json.nlohmann.me/api/json_pointer/parent_pointer/
json_pointer parent_pointer() const
{
if (empty())
{
return *this;
}
json_pointer res = *this;
res.pop_back();
return res;
}
/// @brief remove last reference token
/// @sa https://json.nlohmann.me/api/json_pointer/pop_back/
void pop_back()
{
if (JSON_HEDLEY_UNLIKELY(empty()))
{
JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent", nullptr));
}
reference_tokens.pop_back();
}
/// @brief return last reference token
/// @sa https://json.nlohmann.me/api/json_pointer/back/
const string_t& back() const
{
if (JSON_HEDLEY_UNLIKELY(empty()))
{
JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent", nullptr));
}
return reference_tokens.back();
}
/// @brief append an unescaped token at the end of the reference pointer
/// @sa https://json.nlohmann.me/api/json_pointer/push_back/
void push_back(const string_t& token)
{
reference_tokens.push_back(token);
}
/// @brief append an unescaped token at the end of the reference pointer
/// @sa https://json.nlohmann.me/api/json_pointer/push_back/
void push_back(string_t&& token)
{
reference_tokens.push_back(std::move(token));
}
/// @brief return whether pointer points to the root document
/// @sa https://json.nlohmann.me/api/json_pointer/empty/
bool empty() const noexcept
{
return reference_tokens.empty();
}
private:
/*!
@param[in] s reference token to be converted into an array index
@return integer representation of @a s
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index begins not with a digit
@throw out_of_range.404 if string @a s could not be converted to an integer
@throw out_of_range.410 if an array index exceeds size_type
*/
template<typename BasicJsonType>
static typename BasicJsonType::size_type array_index(const string_t& s)
{
using size_type = typename BasicJsonType::size_type;
// error condition (cf. RFC 6901, Sect. 4)
if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && s[0] == '0'))
{
JSON_THROW(detail::parse_error::create(106, 0, detail::concat("array index '", s, "' must not begin with '0'"), nullptr));
}
// error condition (cf. RFC 6901, Sect. 4)
if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && !(s[0] >= '1' && s[0] <= '9')))
{
JSON_THROW(detail::parse_error::create(109, 0, detail::concat("array index '", s, "' is not a number"), nullptr));
}
const char* p = s.c_str();
char* p_end = nullptr;
errno = 0; // strtoull doesn't reset errno
unsigned long long res = std::strtoull(p, &p_end, 10); // NOLINT(runtime/int)
if (p == p_end // invalid input or empty string
|| errno == ERANGE // out of range
|| JSON_HEDLEY_UNLIKELY(static_cast<std::size_t>(p_end - p) != s.size())) // incomplete read
{
JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", s, "'"), nullptr));
}
// only triggered on special platforms (like 32bit), see also
// https://github.com/nlohmann/json/pull/2203
if (res >= static_cast<unsigned long long>((std::numeric_limits<size_type>::max)())) // NOLINT(runtime/int)
{
JSON_THROW(detail::out_of_range::create(410, detail::concat("array index ", s, " exceeds size_type"), nullptr)); // LCOV_EXCL_LINE
}
return static_cast<size_type>(res);
}
JSON_PRIVATE_UNLESS_TESTED:
json_pointer top() const
{
if (JSON_HEDLEY_UNLIKELY(empty()))
{
JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent", nullptr));
}
json_pointer result = *this;
result.reference_tokens = {reference_tokens[0]};
return result;
}
private:
/*!
@brief create and return a reference to the pointed to value
@complexity Linear in the number of reference tokens.
@throw parse_error.109 if array index is not a number
@throw type_error.313 if value cannot be unflattened
*/
template<typename BasicJsonType>
BasicJsonType& get_and_create(BasicJsonType& j) const
{
auto* result = &j;
// in case no reference tokens exist, return a reference to the JSON value
// j which will be overwritten by a primitive value
for (const auto& reference_token : reference_tokens)
{
switch (result->type())
{
case detail::value_t::null:
{
if (reference_token == "0")
{
// start a new array if reference token is 0
result = &result->operator[](0);
}
else
{
// start a new object otherwise
result = &result->operator[](reference_token);
}
break;
}
case detail::value_t::object:
{
// create an entry in the object
result = &result->operator[](reference_token);
break;
}
case detail::value_t::array:
{
// create an entry in the array
result = &result->operator[](array_index<BasicJsonType>(reference_token));
break;
}
/*
The following code is only reached if there exists a reference
token _and_ the current value is primitive. In this case, we have
an error situation, because primitive values may only occur as
single value; that is, with an empty list of reference tokens.
*/
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
JSON_THROW(detail::type_error::create(313, "invalid value to unflatten", &j));
}
}
return *result;
}
/*!
@brief return a reference to the pointed to value
@note This version does not throw if a value is not present, but tries to
create nested values instead. For instance, calling this function
with pointer `"/this/that"` on a null value is equivalent to calling
`operator[]("this").operator[]("that")` on that value, effectively
changing the null value to an object.
@param[in] ptr a JSON value
@return reference to the JSON value pointed to by the JSON pointer
@complexity Linear in the length of the JSON pointer.
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.404 if the JSON pointer can not be resolved
*/
template<typename BasicJsonType>
BasicJsonType& get_unchecked(BasicJsonType* ptr) const
{
for (const auto& reference_token : reference_tokens)
{
// convert null values to arrays or objects before continuing
if (ptr->is_null())
{
// check if reference token is a number
const bool nums =
std::all_of(reference_token.begin(), reference_token.end(),
[](const unsigned char x)
{
return std::isdigit(x);
});
// change value to array for numbers or "-" or to object otherwise
*ptr = (nums || reference_token == "-")
? detail::value_t::array
: detail::value_t::object;
}
switch (ptr->type())
{
case detail::value_t::object:
{
// use unchecked object access
ptr = &ptr->operator[](reference_token);
break;
}
case detail::value_t::array:
{
if (reference_token == "-")
{
// explicitly treat "-" as index beyond the end
ptr = &ptr->operator[](ptr->m_value.array->size());
}
else
{
// convert array index to number; unchecked access
ptr = &ptr->operator[](array_index<BasicJsonType>(reference_token));
}
break;
}
case detail::value_t::null:
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", reference_token, "'"), ptr));
}
}
return *ptr;
}
/*!
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.402 if the array index '-' is used
@throw out_of_range.404 if the JSON pointer can not be resolved
*/
template<typename BasicJsonType>
BasicJsonType& get_checked(BasicJsonType* ptr) const
{
for (const auto& reference_token : reference_tokens)
{
switch (ptr->type())
{
case detail::value_t::object:
{
// note: at performs range check
ptr = &ptr->at(reference_token);
break;
}
case detail::value_t::array:
{
if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
{
// "-" always fails the range check
JSON_THROW(detail::out_of_range::create(402, detail::concat(
"array index '-' (", std::to_string(ptr->m_value.array->size()),
") is out of range"), ptr));
}
// note: at performs range check
ptr = &ptr->at(array_index<BasicJsonType>(reference_token));
break;
}
case detail::value_t::null:
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", reference_token, "'"), ptr));
}
}
return *ptr;
}
/*!
@brief return a const reference to the pointed to value
@param[in] ptr a JSON value
@return const reference to the JSON value pointed to by the JSON
pointer
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.402 if the array index '-' is used
@throw out_of_range.404 if the JSON pointer can not be resolved
*/
template<typename BasicJsonType>
const BasicJsonType& get_unchecked(const BasicJsonType* ptr) const
{
for (const auto& reference_token : reference_tokens)
{
switch (ptr->type())
{
case detail::value_t::object:
{
// use unchecked object access
ptr = &ptr->operator[](reference_token);
break;
}
case detail::value_t::array:
{
if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
{
// "-" cannot be used for const access
JSON_THROW(detail::out_of_range::create(402, detail::concat("array index '-' (", std::to_string(ptr->m_value.array->size()), ") is out of range"), ptr));
}
// use unchecked array access
ptr = &ptr->operator[](array_index<BasicJsonType>(reference_token));
break;
}
case detail::value_t::null:
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", reference_token, "'"), ptr));
}
}
return *ptr;
}
/*!
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.402 if the array index '-' is used
@throw out_of_range.404 if the JSON pointer can not be resolved
*/
template<typename BasicJsonType>
const BasicJsonType& get_checked(const BasicJsonType* ptr) const
{
for (const auto& reference_token : reference_tokens)
{
switch (ptr->type())
{
case detail::value_t::object:
{
// note: at performs range check
ptr = &ptr->at(reference_token);
break;
}
case detail::value_t::array:
{
if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
{
// "-" always fails the range check
JSON_THROW(detail::out_of_range::create(402, detail::concat(
"array index '-' (", std::to_string(ptr->m_value.array->size()),
") is out of range"), ptr));
}
// note: at performs range check
ptr = &ptr->at(array_index<BasicJsonType>(reference_token));
break;
}
case detail::value_t::null:
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
JSON_THROW(detail::out_of_range::create(404, detail::concat("unresolved reference token '", reference_token, "'"), ptr));
}
}
return *ptr;
}
/*!
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
*/
template<typename BasicJsonType>
bool contains(const BasicJsonType* ptr) const
{
for (const auto& reference_token : reference_tokens)
{
switch (ptr->type())
{
case detail::value_t::object:
{
if (!ptr->contains(reference_token))
{
// we did not find the key in the object
return false;
}
ptr = &ptr->operator[](reference_token);
break;
}
case detail::value_t::array:
{
if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
{
// "-" always fails the range check
return false;
}
if (JSON_HEDLEY_UNLIKELY(reference_token.size() == 1 && !("0" <= reference_token && reference_token <= "9")))
{
// invalid char
return false;
}
if (JSON_HEDLEY_UNLIKELY(reference_token.size() > 1))
{
if (JSON_HEDLEY_UNLIKELY(!('1' <= reference_token[0] && reference_token[0] <= '9')))
{
// first char should be between '1' and '9'
return false;
}
for (std::size_t i = 1; i < reference_token.size(); i++)
{
if (JSON_HEDLEY_UNLIKELY(!('0' <= reference_token[i] && reference_token[i] <= '9')))
{
// other char should be between '0' and '9'
return false;
}
}
}
const auto idx = array_index<BasicJsonType>(reference_token);
if (idx >= ptr->size())
{
// index out of range
return false;
}
ptr = &ptr->operator[](idx);
break;
}
case detail::value_t::null:
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
{
// we do not expect primitive values if there is still a
// reference token to process
return false;
}
}
}
// no reference token left means we found a primitive value
return true;
}
/*!
@brief split the string input to reference tokens
@note This function is only called by the json_pointer constructor.
All exceptions below are documented there.
@throw parse_error.107 if the pointer is not empty or begins with '/'
@throw parse_error.108 if character '~' is not followed by '0' or '1'
*/
static std::vector<string_t> split(const string_t& reference_string)
{
std::vector<string_t> result;
// special case: empty reference string -> no reference tokens
if (reference_string.empty())
{
return result;
}
// check if nonempty reference string begins with slash
if (JSON_HEDLEY_UNLIKELY(reference_string[0] != '/'))
{
JSON_THROW(detail::parse_error::create(107, 1, detail::concat("JSON pointer must be empty or begin with '/' - was: '", reference_string, "'"), nullptr));
}
// extract the reference tokens:
// - slash: position of the last read slash (or end of string)
// - start: position after the previous slash
for (
// search for the first slash after the first character
std::size_t slash = reference_string.find_first_of('/', 1),
// set the beginning of the first reference token
start = 1;
// we can stop if start == 0 (if slash == string_t::npos)
start != 0;
// set the beginning of the next reference token
// (will eventually be 0 if slash == string_t::npos)
start = (slash == string_t::npos) ? 0 : slash + 1,
// find next slash
slash = reference_string.find_first_of('/', start))
{
// use the text between the beginning of the reference token
// (start) and the last slash (slash).
auto reference_token = reference_string.substr(start, slash - start);
// check reference tokens are properly escaped
for (std::size_t pos = reference_token.find_first_of('~');
pos != string_t::npos;
pos = reference_token.find_first_of('~', pos + 1))
{
JSON_ASSERT(reference_token[pos] == '~');
// ~ must be followed by 0 or 1
if (JSON_HEDLEY_UNLIKELY(pos == reference_token.size() - 1 ||
(reference_token[pos + 1] != '0' &&
reference_token[pos + 1] != '1')))
{
JSON_THROW(detail::parse_error::create(108, 0, "escape character '~' must be followed with '0' or '1'", nullptr));
}
}
// finally, store the reference token
detail::unescape(reference_token);
result.push_back(reference_token);
}
return result;
}
private:
/*!
@param[in] reference_string the reference string to the current value
@param[in] value the value to consider
@param[in,out] result the result object to insert values to
@note Empty objects or arrays are flattened to `null`.
*/
template<typename BasicJsonType>
static void flatten(const string_t& reference_string,
const BasicJsonType& value,
BasicJsonType& result)
{
switch (value.type())
{
case detail::value_t::array:
{
if (value.m_value.array->empty())
{
// flatten empty array as null
result[reference_string] = nullptr;
}
else
{
// iterate array and use index as reference string
for (std::size_t i = 0; i < value.m_value.array->size(); ++i)
{
flatten(detail::concat(reference_string, '/', std::to_string(i)),
value.m_value.array->operator[](i), result);
}
}
break;
}
case detail::value_t::object:
{
if (value.m_value.object->empty())
{
// flatten empty object as null
result[reference_string] = nullptr;
}
else
{
// iterate object and use keys as reference string
for (const auto& element : *value.m_value.object)
{
flatten(detail::concat(reference_string, '/', detail::escape(element.first)), element.second, result);
}
}
break;
}
case detail::value_t::null:
case detail::value_t::string:
case detail::value_t::boolean:
case detail::value_t::number_integer:
case detail::value_t::number_unsigned:
case detail::value_t::number_float:
case detail::value_t::binary:
case detail::value_t::discarded:
default:
{
// add primitive value with its reference string
result[reference_string] = value;
break;
}
}
}
/*!
@param[in] value flattened JSON
@return unflattened JSON
@throw parse_error.109 if array index is not a number
@throw type_error.314 if value is not an object
@throw type_error.315 if object values are not primitive
@throw type_error.313 if value cannot be unflattened
*/
template<typename BasicJsonType>
static BasicJsonType
unflatten(const BasicJsonType& value)
{
if (JSON_HEDLEY_UNLIKELY(!value.is_object()))
{
JSON_THROW(detail::type_error::create(314, "only objects can be unflattened", &value));
}
BasicJsonType result;
// iterate the JSON object values
for (const auto& element : *value.m_value.object)
{
if (JSON_HEDLEY_UNLIKELY(!element.second.is_primitive()))
{
JSON_THROW(detail::type_error::create(315, "values in object must be primitive", &element.second));
}
// assign value to reference pointed to by JSON pointer; Note that if
// the JSON pointer is "" (i.e., points to the whole value), function
// get_and_create returns a reference to result itself. An assignment
// will then create a primitive value.
json_pointer(element.first).get_and_create(result) = element.second;
}
return result;
}
// can't use conversion operator because of ambiguity
json_pointer<string_t> convert() const&
{
json_pointer<string_t> result;
result.reference_tokens = reference_tokens;
return result;
}
json_pointer<string_t> convert()&&
{
json_pointer<string_t> result;
result.reference_tokens = std::move(reference_tokens);
return result;
}
/*!
@brief compares two JSON pointers for equality
@param[in] lhs JSON pointer to compare
@param[in] rhs JSON pointer to compare
@return whether @a lhs is equal to @a rhs
@complexity Linear in the length of the JSON pointer
@exceptionsafety No-throw guarantee: this function never throws exceptions.
*/
template<typename RefStringTypeLhs, typename RefStringTypeRhs>
// NOLINTNEXTLINE(readability-redundant-declaration)
friend bool operator==(json_pointer<RefStringTypeLhs> const& lhs,
json_pointer<RefStringTypeRhs> const& rhs) noexcept;
/*!
@brief compares two JSON pointers for inequality
@param[in] lhs JSON pointer to compare
@param[in] rhs JSON pointer to compare
@return whether @a lhs is not equal @a rhs
@complexity Linear in the length of the JSON pointer
@exceptionsafety No-throw guarantee: this function never throws exceptions.
*/
template<typename RefStringTypeLhs, typename RefStringTypeRhs>
// NOLINTNEXTLINE(readability-redundant-declaration)
friend bool operator!=(json_pointer<RefStringTypeLhs> const& lhs,
json_pointer<RefStringTypeRhs> const& rhs) noexcept;
/// the reference tokens
std::vector<string_t> reference_tokens;
};
// functions cannot be defined inside class due to ODR violations
template<typename RefStringTypeLhs, typename RefStringTypeRhs>
inline bool operator==(json_pointer<RefStringTypeLhs> const& lhs,
json_pointer<RefStringTypeRhs> const& rhs) noexcept
{
return lhs.reference_tokens == rhs.reference_tokens;
}
template<typename RefStringTypeLhs, typename RefStringTypeRhs>
inline bool operator!=(json_pointer<RefStringTypeLhs> const& lhs,
json_pointer<RefStringTypeRhs> const& rhs) noexcept
{
return !(lhs == rhs);
}
NLOHMANN_JSON_NAMESPACE_END