def test_mergesort__object_element_array__sorted(faker):
class TestObject:
"""Test class to test object sorting
Note: mergesort is unstable method. It means that it does not guarantee that two objects
with same value always appear in the same order.
Thus, the "__eq__" method implementation has been overwritten to solve this limitation
in the test validation.
"""
def __init__(self, value: int):
self.value = value
def __eq__(self, other):
return self.value == other.value
def __repr__(self):
return f"Test({self.value})"
def __str__(self):
return f"<Test object - value: {self.value}>"
original_input = [TestObject(random.randrange(1000)) for _ in range(1000)]
input_list = list(original_input)
sut.mergesort(input_list, lambda a, b: a.value < b.value)
sorted_original_input = sorted(original_input, key=lambda e: e.value)
assert input_list == sorted_original_input
def test_mergesort__decreasing_sorted_multi_element_array__sorted():
original_input = sorted([random.randrange(1000) for _ in range(1000)],
reverse=True)
input_list = list(original_input)
sut.mergesort(input_list)
reversed_original_input = original_input[::-1]
assert input_list == reversed_original_input
def test_mergesort__float_element_array__sorted(faker):
original_input = [random.random() for _ in range(1000)]
input_list = list(original_input)
sut.mergesort(input_list)
assert input_list == sorted(original_input)
def test_mergesort__string_element_array__sorted(faker):
original_input = [faker.pystr() for _ in range(1000)]
input_list = list(original_input)
sut.mergesort(input_list)
assert input_list == sorted(original_input)
def test_mergesort__empty_array__no_error():
original_input = []
input_list = list(original_input)
sut.mergesort(input_list)
assert input_list == []
def test_mergesort__increasing_sorted_multi_element_array__sorted():
original_input = sorted([random.randrange(1000) for _ in range(1000)])
input_list = list(original_input)
sut.mergesort(input_list)
assert input_list == original_input
def test_mergesort__random_multi_element_array__sorted():
original_input = [random.randrange(1000) for _ in range(1000)]
input_list = list(original_input)
sut.mergesort(input_list)
assert input_list == sorted(original_input)
def test_mergesort__one_element_array__no_error():
original_input = [random.randrange(1000)]
input_list = list(original_input)
sut.mergesort(input_list)
assert input_list == original_input