Adds the directory of the file at the specified path as a base
        path to find other files in.

def _add_current_codedir(self, path):
        """Adds the directory of the file at the specified path as a base
        path to find other files in.
        """
        dirpath = self.tramp.dirname(path)
        if dirpath not in self.basepaths:
            self.basepaths.append(dirpath)
            self.rescan()