Crash in split_program_name if the command line is program name only

[defisym]

auto commandLine="\"C:\\example.exe\""

try {
    app.parse(commandLine, true);
}
catch (const CLI::ParseError& e) {
    //return app.exit(e);
}

split_program_name will throw std::out_of_range exception, if nothing left in command line after removing the program name here:

vals.second = (esp != std::string::npos) ? commandline.substr(esp + 1) : std::string{};

a quick fix is:

trim(commandline);
auto length = commandline.length();
auto esp = commandline.find_first_of(' ', 1);
while(detail::check_path(commandline.substr(0, esp).c_str()) != path_type::file){
......
// strip the program name
vals.second = (esp != std::string::npos) && (esp < length) ? commandline.substr(esp + 1) : std::string{};

[phlptp]

Thanks for catching this, the fix has been merged into main