def read(file = find_file, format: :auto)
      if file.nil?
        raise ReadError, 'No file found to read configuration from!'
      elsif !::File.exist?(file)
        raise ReadError, "Configuration file `#{file}` does not exist!"
      end

      merge(unmarshal(file, format: format))
    end
def read(file = find_file, format: :auto)
      if file.nil?
        raise ReadError, 'No file found to read configuration from!'
      elsif !::File.exist?(file)
        raise ReadError, "Configuration file `#{file}` does not exist!"
      end

      merge(unmarshal(file, format: format))
    end
Find and read a configuration file.

 If the file doesn't exist or if there is an error loading it
 the TTY::Config::ReadError will be raised.

 @param [String] file
   the path to the configuration file to be read

 @param [String] format
   the format to read configuration in

 @raise [TTY::Config::ReadError]

 @api public