Method to_config

tests/ConfigFileTest.cpp:826–826

  public:
    EvilConfig() = default;
    std::string to_config(const CLI::App *, bool, bool, std::string) const override { throw CLI::FileError("evil"); }

    std::vector<CLI::ConfigItem> from_config(std::istream &) const override { throw CLI::FileError("evil"); }
};