def create_missing_file
      raise Errno::EISDIR, path.to_s if File.directory?(@path)

      return if File.exist?(@path) # Unnecessary check, probably.
      dirname = RealFile.dirname @path

      unless dirname == '.'
        dir = FileSystem.find dirname

        raise Errno::ENOENT, path.to_s unless dir.is_a? FakeDir
      end

      @file = FileSystem.add(path, FakeFile.new)
    end
def create_missing_file
      raise Errno::EISDIR, path.to_s if File.directory?(@path)

      return if File.exist?(@path) # Unnecessary check, probably.
      dirname = RealFile.dirname @path

      unless dirname == '.'
        dir = FileSystem.find dirname

        raise Errno::ENOENT, path.to_s unless dir.is_a? FakeDir
      end

      @file = FileSystem.add(path, FakeFile.new)
    end
Create a missing file if the path is valid.