def test_recommend_lerpZeroSumWeights_failure(self):
        """
        Test that the recommender fails when the sum of all weights is zero with LERP (and NLERP)
        """
        for index in [self.unstructured_text_index, self.structured_text_index]:
            for method in [InterpolationMethod.LERP, InterpolationMethod.NLERP]:
                with self.subTest(type=index.type, method=method):
                    self._populate_index(index)

                    with self.assertRaisesStrict(InvalidArgumentError) as ex:
                        self.recommender.recommend(
                            index_name=index.name,
                            documents={"1": 1, "2": 2, "3": -3},
                            tensor_fields=['title'],
                            interpolation_method=method,
                            exclude_input_documents=False,
                        )
                    self.assertIn('Sum of weights is zero', str(ex.exception))

        Test that the recommender fails when the sum of all weights is zero with LERP (and NLERP)
        
tests/integ_tests/core/search/test_recommender.py