Method adjustString

tests/catch.h:1050–1055

                m_str( adjustString( str ) )
            {}
            std::string adjustString( std::string const& str ) const {
                return m_caseSensitivity == CaseSensitive::No
                    ? toLower( str )
                    : str;

            }
            std::string toStringSuffix() const
            {
                return m_caseSensitivity == CaseSensitive::No