# File lib/grit/git-ruby/file_index.rb, line 34
    def initialize(repo_path)
      @index_file = File.join(repo_path, 'file-index')
      if File.file?(@index_file) && (File.size(@index_file) < Grit::GitRuby::FileIndex.max_file_size)
        read_index
      else
        raise IndexFileNotFound
      end
    end