def test_size_with_repeated_insert(self):
tree = PrefixTree()
# Verify size after initializing tree
assert tree.size == 0
assert tree.is_empty() is True
# Verify size after first insert
tree.insert('A')
assert tree.size == 1
assert tree.is_empty() is False
# Verify size after repeating first insert
tree.insert('A')
assert tree.size == 1
# Verify size after second insert
tree.insert('ABC')
assert tree.size == 2
# Verify size after repeating second insert
tree.insert('ABC')
assert tree.size == 2
# Verify size after third insert
tree.insert('ABD')
assert tree.size == 3
# Verify size after repeating third insert
tree.insert('ABD')
assert tree.size == 3
# Verify size after fourth insert
tree.insert('XYZ')
assert tree.size == 4
# Verify size after repeating fourth insert
tree.insert('XYZ')
assert tree.size == 4
def test_contains(self):
strings = ['ABC', 'ABD', 'A', 'XYZ']
tree = PrefixTree(strings)
# Verify contains for all substrings
assert tree.contains('ABC') is True
assert tree.contains('ABD') is True
assert tree.contains('AB') is False
assert tree.contains('BC') is False
assert tree.contains('BD') is False
assert tree.contains('A') is True
assert tree.contains('B') is False
assert tree.contains('C') is False
assert tree.contains('D') is False
assert tree.contains('XYZ') is True
assert tree.contains('XY') is False
assert tree.contains('YZ') is False
assert tree.contains('X') is False
assert tree.contains('Y') is False
assert tree.contains('Z') is False
def test_size_and_is_empty(self):
tree = PrefixTree()
# Verify size after initializing tree
assert tree.size == 0
assert tree.is_empty() is True
# Verify size after first insert
tree.insert('A')
assert tree.size == 1
assert tree.is_empty() is False
# Verify size after second insert
tree.insert('ABC')
assert tree.size == 2
assert tree.is_empty() is False
# Verify size after third insert
tree.insert('ABD')
assert tree.size == 3
assert tree.is_empty() is False
# Verify size after fourth insert
tree.insert('XYZ')
assert tree.size == 4
assert tree.is_empty() is False
