docs: def GetUnknownFiles(self):
  		"""Return a list of files unknown to the VCS."""
  		args = []
  		status = RunShell(["hg", "status", "--rev", self.base_rev, "-u", "."],
  				silent_ok=True)
  		unknown_files = []
  		for line in status.splitlines():
  			st, fn = line.split(" ", 1)
  			if st == "?":
  				unknown_files.append(fn)
  		return unknown_files