def test_prob_death_is_one_if_fitness_zero(self, example_properties_w_20):
"""
Asserts that the probability calculated from prob_death is one
if fitness equals zero.
"""
animal = Animal(example_properties_w_20)
animal.weight = 0
animal.find_fitness()
assert animal.prob_death() == 1
def test_not_true_if_death_prob_is_one(self, example_properties_w_20):
"""
Assert that will_animal_live does not return True if probability of
dying is one.
"""
animal = Animal(example_properties_w_20)
animal.weight = 0
animal.find_fitness()
assert animal.will_animal_live() is not True
def test_fitness_zero_if_weight_zero(self, example_properties_w_20):
"""
Checks that find_fitness method calculates a fitness of zero if
weight of the animal is zero.
"""
animal = Animal(example_properties_w_20)
animal.weight = 0
animal.find_fitness()
assert animal.fitness == 0
