def _validate_classpath_tuples(self, classpath, target):
    """Validates that all files are located within the working directory, to simplify relativization.

    :param classpath: The list of classpath tuples. Each tuple is a 2-tuple of ivy_conf and
                      ClasspathEntry.
    :param target: The target that the classpath tuple is being registered for.
    :raises: `TaskError` when the path is outside the work directory
    """
    for classpath_tuple in classpath:
      conf, classpath_entry = classpath_tuple
      path = classpath_entry.path
      if os.path.relpath(path, self._pants_workdir).startswith(os.pardir):
        raise TaskError(
          'Classpath entry {} for target {} is located outside the working directory "{}".'
          .format(path, target.address.spec, self._pants_workdir))
Validates that all files are located within the working directory, to simplify relativization.

    :param classpath: The list of classpath tuples. Each tuple is a 2-tuple of ivy_conf and
                      ClasspathEntry.
    :param target: The target that the classpath tuple is being registered for.
    :raises: `TaskError` when the path is outside the work directory