@Test
public void testBuild() {

  GeometryOperator preUnionGeometryOperator = mock(GeometryOperator.class);
  GeometryOperator postUnionGeometryOperator = mock(GeometryOperator.class);
  LocationUpdateFieldFactory factory =
      new LocationUpdateFieldFactory(preUnionGeometryOperator, postUnionGeometryOperator);
  UpdateParent.UpdateField updateField = factory.build();
  assertThat(updateField, is(instanceOf(LocationUpdateField.class)));
  LocationUpdateField locationUpdateField = (LocationUpdateField) updateField;
  assertThat(locationUpdateField.getPreUnionGeometryOperator(), is(preUnionGeometryOperator));
  assertThat(locationUpdateField.getPostUnionGeometryOperator(), is(postUnionGeometryOperator));
}