:white_check_mark: improved test coverage
:white_check_mark: improved test coverage

nlohmann/json,hunter-packages/json,theodelrieu/json,hunter-packages/json,kaidokert/json,Newbrick/json,nlohmann/json,stanmihai4/json,nlohmann/json,stanmihai4/json,theodelrieu/json,hunter-packages/json,Newbrick/json,stanmihai4/json,Newbrick/json,kaidokert/json,kaidokert/json