Find out the last commit for specific file using rugged

last_commit_for_path_within_head_repo_method

  def last_commit_for_path_within_head_repo(path)
    # equal to `git rev-list --max-count 1 HEAD #{path}`
    walker = Rugged::Walker.new(Rugged:Repository)
    walker.sorting(Rugged::SORT_DATE)
    walker.push(head_commit)
    walker.hide(base_commit)
    walker.each { |commit|
      return commit.oid if commit.diff(paths: [path]).size > 0
     }
    base_commit
  end