diff --git a/include/nlohmann/detail/input/json_sax.hpp b/include/nlohmann/detail/input/json_sax.hpp index 561bbe1c..6f3aa99c 100644 --- a/include/nlohmann/detail/input/json_sax.hpp +++ b/include/nlohmann/detail/input/json_sax.hpp @@ -349,10 +349,10 @@ class json_sax_dom_callback_parser : public json_sax bool start_object(std::size_t len) override { // check callback for object start - const bool keep = callback(static_cast(ref_stack.size()) + 1, parse_event_t::object_start, discarded); + const bool keep = callback(static_cast(ref_stack.size()), parse_event_t::object_start, discarded); keep_stack.push_back(keep); - auto val = handle_value(BasicJsonType::value_t::object); + auto val = handle_value(BasicJsonType::value_t::object, true); ref_stack.push_back(val.second); // check object limit @@ -424,10 +424,10 @@ class json_sax_dom_callback_parser : public json_sax bool start_array(std::size_t len) override { - const bool keep = callback(static_cast(ref_stack.size()) + 1, parse_event_t::array_start, discarded); + const bool keep = callback(static_cast(ref_stack.size()), parse_event_t::array_start, discarded); keep_stack.push_back(keep); - auto val = handle_value(BasicJsonType::value_t::array); + auto val = handle_value(BasicJsonType::value_t::array, true); ref_stack.push_back(val.second); // check array limit @@ -507,15 +507,22 @@ class json_sax_dom_callback_parser : public json_sax private: /*! + @param[in] v value to add to the JSON value we build during parsing + @param[in] skip_callback whether we should skip calling the callback + function; this is required after start_array() and + start_object() SAX events, because otherwise we would call the + callback function with an empty array or object, respectively. + @invariant If the ref stack is empty, then the passed value will be the new root. @invariant If the ref stack contains a value, then it is an array or an object to which we can add elements + @return pair of boolean (whether value should be kept) and pointer (to the passed value in the ref_stack hierarchy; nullptr if not kept) */ template - std::pair handle_value(Value&& v) + std::pair handle_value(Value&& v, const bool skip_callback = false) { assert(not keep_stack.empty()); @@ -526,9 +533,11 @@ class json_sax_dom_callback_parser : public json_sax return {false, nullptr}; } - // create value and check callback + // create value auto value = BasicJsonType(std::forward(v)); - const bool keep = callback(static_cast(ref_stack.size()), parse_event_t::value, value); + + // check callback + const bool keep = skip_callback or callback(static_cast(ref_stack.size()), parse_event_t::value, value); // do not handle this value if we just learnt it shall be discarded if (not keep) diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp index fa7f585d..95077359 100644 --- a/single_include/nlohmann/json.hpp +++ b/single_include/nlohmann/json.hpp @@ -1697,13 +1697,6 @@ class wide_string_input_adapter : public input_adapter_protocol std::char_traits::int_type get_character() noexcept override { - // unget_character() was called previously: return the last character - if (next_unget) - { - next_unget = false; - return last_char; - } - // check if buffer needs to be filled if (utf8_bytes_index == utf8_bytes_filled) { @@ -1723,12 +1716,7 @@ class wide_string_input_adapter : public input_adapter_protocol // use buffer assert(utf8_bytes_filled > 0); assert(utf8_bytes_index < utf8_bytes_filled); - return (last_char = utf8_bytes[utf8_bytes_index++]); - } - - void unget_character() noexcept override - { - next_unget = true; + return utf8_bytes[utf8_bytes_index++]; } private: @@ -1852,11 +1840,6 @@ class wide_string_input_adapter : public input_adapter_protocol std::size_t utf8_bytes_index = 0; /// number of valid bytes in the utf8_codes array std::size_t utf8_bytes_filled = 0; - - /// the last character (returned after unget_character() is called) - std::char_traits::int_type last_char = 0; - /// whether get_character() should return last_char - bool next_unget = false; }; class input_adapter @@ -3670,10 +3653,10 @@ class json_sax_dom_callback_parser : public json_sax bool start_object(std::size_t len) override { // check callback for object start - const bool keep = callback(static_cast(ref_stack.size()) + 1, parse_event_t::object_start, discarded); + const bool keep = callback(static_cast(ref_stack.size()), parse_event_t::object_start, discarded); keep_stack.push_back(keep); - auto val = handle_value(BasicJsonType::value_t::object); + auto val = handle_value(BasicJsonType::value_t::object, true); ref_stack.push_back(val.second); // check object limit @@ -3745,10 +3728,10 @@ class json_sax_dom_callback_parser : public json_sax bool start_array(std::size_t len) override { - const bool keep = callback(static_cast(ref_stack.size()) + 1, parse_event_t::array_start, discarded); + const bool keep = callback(static_cast(ref_stack.size()), parse_event_t::array_start, discarded); keep_stack.push_back(keep); - auto val = handle_value(BasicJsonType::value_t::array); + auto val = handle_value(BasicJsonType::value_t::array, true); ref_stack.push_back(val.second); // check array limit @@ -3828,15 +3811,22 @@ class json_sax_dom_callback_parser : public json_sax private: /*! + @param[in] v value to add to the JSON value we build during parsing + @param[in] skip_callback whether we should skip calling the callback + function; this is required after start_array() and + start_object() SAX events, because otherwise we would call the + callback function with an empty array or object, respectively. + @invariant If the ref stack is empty, then the passed value will be the new root. @invariant If the ref stack contains a value, then it is an array or an object to which we can add elements + @return pair of boolean (whether value should be kept) and pointer (to the passed value in the ref_stack hierarchy; nullptr if not kept) */ template - std::pair handle_value(Value&& v) + std::pair handle_value(Value&& v, const bool skip_callback = false) { assert(not keep_stack.empty()); @@ -3847,9 +3837,11 @@ class json_sax_dom_callback_parser : public json_sax return {false, nullptr}; } - // create value and check callback + // create value auto value = BasicJsonType(std::forward(v)); - const bool keep = callback(static_cast(ref_stack.size()), parse_event_t::value, value); + + // check callback + const bool keep = skip_callback or callback(static_cast(ref_stack.size()), parse_event_t::value, value); // do not handle this value if we just learnt it shall be discarded if (not keep)