def test_push_does_not_add_hypothesis_that_falls_below_beam_threshold(self): # arrange stack = _Stack(3, 0.5) poor_hypothesis = _Hypothesis(0.01) # act stack.push(_Hypothesis(0.9)) # greatly superior hypothesis stack.push(poor_hypothesis) # assert self.assertFalse(poor_hypothesis in stack)
def test_best_returns_the_best_hypothesis(self): # arrange stack = _Stack(3) best_hypothesis = _Hypothesis(0.99) # act stack.push(_Hypothesis(0.0)) stack.push(best_hypothesis) stack.push(_Hypothesis(0.5)) # assert self.assertEqual(stack.best(), best_hypothesis)
def test_push_bumps_off_worst_hypothesis_when_stack_is_full(self): # arrange stack = _Stack(3) poor_hypothesis = _Hypothesis(0.01) # act stack.push(_Hypothesis(0.2)) stack.push(poor_hypothesis) stack.push(_Hypothesis(0.1)) stack.push(_Hypothesis(0.3)) # assert self.assertFalse(poor_hypothesis in stack)
def test_push_removes_hypotheses_that_fall_below_beam_threshold(self): # arrange stack = _Stack(3, 0.5) poor_hypothesis = _Hypothesis(0.01) worse_hypothesis = _Hypothesis(0.009) # act stack.push(poor_hypothesis) stack.push(worse_hypothesis) stack.push(_Hypothesis(0.9)) # greatly superior hypothesis # assert self.assertFalse(poor_hypothesis in stack) self.assertFalse(worse_hypothesis in stack)
def test_best_returns_none_when_stack_is_empty(self): # arrange stack = _Stack(3) # assert self.assertEqual(stack.best(), None)