def test_distortion_score_of_first_expansion(self):
# arrange
stack_decoder = StackDecoder(None, None)
stack_decoder.distortion_factor = 0.5
hypothesis = _Hypothesis()
# act
score = stack_decoder.distortion_score(hypothesis, (8, 10))
# assert
# expansion from empty hypothesis always has zero distortion cost
self.assertEqual(score, 0.0)
def test_distortion_score_of_first_expansion(self):
# arrange
stack_decoder = StackDecoder(None, None)
stack_decoder.distortion_factor = 0.5
hypothesis = _Hypothesis()
# act
score = stack_decoder.distortion_score(hypothesis, (8, 10))
# assert
# expansion from empty hypothesis always has zero distortion cost
self.assertEqual(score, 0.0)
def test_distortion_score(self):
# arrange
stack_decoder = StackDecoder(None, None)
stack_decoder.distortion_factor = 0.5
hypothesis = _Hypothesis()
hypothesis.src_phrase_span = (3, 5)
# act
score = stack_decoder.distortion_score(hypothesis, (8, 10))
# assert
expected_score = log(stack_decoder.distortion_factor) * (8 - 5)
self.assertEqual(score, expected_score)
def test_distortion_score(self):
# arrange
stack_decoder = StackDecoder(None, None)
stack_decoder.distortion_factor = 0.5
hypothesis = _Hypothesis()
hypothesis.src_phrase_span = (3, 5)
# act
score = stack_decoder.distortion_score(hypothesis, (8, 10))
# assert
expected_score = log(stack_decoder.distortion_factor) * (8 - 5)
self.assertEqual(score, expected_score)
