import tensorflow as tf

  def test_output_equal_in_replace_empty_string_with_random_number(self):
    string_placeholder = tf.placeholder(tf.string, shape=[])
    replaced_string = inputs._replace_empty_string_with_random_number(
        string_placeholder)

    test_string = 'hello world'
    feed_dict = {string_placeholder: test_string}

    with self.test_session() as sess:
      out_string = sess.run(replaced_string, feed_dict=feed_dict)

    self.assertEqual(test_string, out_string)

  def test_output_is_integer_in_replace_empty_string_with_random_number(self):

    string_placeholder = tf.placeholder(tf.string, shape=[])
    replaced_string = inputs._replace_empty_string_with_random_number(
        string_placeholder)

    empty_string = ''
    feed_dict = {string_placeholder: empty_string}

    tf.set_random_seed(0)

    with self.test_session() as sess:
      out_string = sess.run(replaced_string, feed_dict=feed_dict)

    # Test whether out_string is a string which represents an integer.
    int(out_string)  # throws an error if out_string is not castable to int.

