def ll_list():
"""Sets up a linked list instance along with adds a few nodes for testing"""
ll = LinkedList()
ll.insert("a")
ll.insert("b")
ll.insert("c")
return ll
def test_LinkedList_str():
ll = LinkedList()
ll.insert("a")
ll.insert("b")
actual = str(ll)
expected = "{ b } -> { a } -> NULL"
assert actual == expected
def test_LinkedList_kth_from_end_same_length():
ll = LinkedList()
ll.insert(2)
ll.insert(8)
actual = ll.kth_from_end(2)
expected = 8
assert actual == expected
def test_LinkedList_kth_from_end_ValueError_Exception():
ll = LinkedList()
ll.insert(2)
ll.insert(8)
ll.insert(3)
ll.insert(1)
with pytest.raises(ValueError):
ll.kth_from_end(-6)
def test_LinkedList_kth_from_end_2():
ll = LinkedList()
ll.insert(2)
ll.insert(8)
ll.insert(3)
ll.insert(1)
actual = ll.kth_from_end(2)
expected = 3
assert actual == expected
def test_merge_list_list2_none():
list1 = LinkedList()
list2 = LinkedList()
list1.insert("c")
list1.insert("b")
list1.insert("a")
actual = str(merge_list(list1, list2))
expected = "{ a } -> { b } -> { c } -> NULL"
assert actual == expected
def test_merge_list_equal_lists():
list1 = LinkedList()
list2 = LinkedList()
list1.insert("e")
list1.insert("c")
list1.insert("a")
list2.insert("f")
list2.insert("d")
list2.insert("b")
actual = str(merge_list(list1, list2))
expected = "{ a } -> { b } -> { c } -> { d } -> { e } -> { f } -> NULL"
assert actual == expected
def test_merge_list_list1_longer():
list1 = LinkedList()
list2 = LinkedList()
list1.insert("3")
list1.insert("1")
list1.insert("4")
list2.insert("9")
list2.insert("5")
actual = str(merge_list(list1, list2))
expected = "{ 4 } -> { 5 } -> { 1 } -> { 9 } -> { 3 } -> NULL"
assert actual == expected
def test_LinkedList_insert():
ll = LinkedList()
ll.insert("a")
ll.insert("b")
assert ll.head.value == "b"
assert ll.head.next.value == "a"
def ll_list_merge():
"""Sets up two linked list instances along with some nodes for testing"""
list1 = LinkedList()
list1.insert("c")
list1.insert("b")
list1.insert("a")