# File lib/grit/git.rb, line 159
    def check_applies(head_sha, applies_sha)
      git_index = create_tempfile('index', true)
      (o1, exit1) = raw_git("git read-tree #{head_sha} 2>/dev/null", git_index)
      (o2, exit2) = raw_git("git diff #{applies_sha}^ #{applies_sha} | git apply --check --cached >/dev/null 2>/dev/null", git_index)
      return (exit1 + exit2)
    end