def test_countPrefix():
t = Trie()
t.add("abcd")
assert(len(t) == 1)
assert(t.countPrefix("abc") == 1)
trie = Trie()
try:
assert(trie.countPrefix("word") == 0)
except TrieEmptyError as e:
assert(e.message == "TrieEmptyError: 'countPrefix(): Trie is empty'")
trie.add("word")
trie.add("word")
trie.add("words")
trie.add("words")
trie.add("words")
trie.add("words")
trie.add("sword")
trie.add("ward")
assert(len(trie) == 4)
assert(trie.countPrefix("w") == 3)
assert(trie.countPrefix("word") == 2)
assert(trie.countPrefix("wor") == 2)
assert(trie.countPrefix("wort") == 0)
assert(trie.countPrefix("words") == 1)
assert(trie.countPrefix("sword") == 1)
assert(trie.countPrefix("swo") == 1)
assert(trie.countPrefix("so") == 0)
def test_removePrefix():
trie = Trie()
trie.add("abcd")
trie.add("abc")
trie.add("abd")
trie.add("abce")
trie.add("words")
trie.add("swords")
assert(trie.countPrefix("abc") == 3)
assert(trie.countPrefix("a") == 4)
assert(len(trie) == 6)
trie.removePrefix("abc") # removes 'abc', 'abcd' and 'abce'
# 'ab' should only have 'd' as its child now
assert(len(trie) == 3)
assert(trie.root['a'].children['b'].children.items.keys() == ['d'])
assert(trie.countPrefix("abc") == 0)
assert(trie.countPrefix("a") == 1)
assert(trie.findKeysMatchingPrefix("a") == ["abd"])
# try and remove 'abc' again - nothing should change
trie.removePrefix("abc") # removes 'abc', 'abcd' and 'abce'
assert(len(trie) == 3)
assert(trie.root['a'].children['b'].children.items.keys() == ['d'])
assert(trie.countPrefix("abc") == 0)
assert(trie.countPrefix("a") == 1)
assert(trie.findKeysMatchingPrefix("a") == ["abd"])
# remove 'a*'
trie.removePrefix("a") # removes 'abd'
assert(len(trie) == 2)
assert(sorted(trie.root.items.keys()) == ['s', 'w'])
assert(trie.countPrefix("abc") == 0)
assert(trie.countPrefix("a") == 0)
assert(trie.findKeysMatchingPrefix("a") == [])
assert(trie.findKeysMatchingPrefix("") == ["swords", "words"])
# flush the whole trie
trie.removePrefix("")
assert(trie.root == None)
assert(len(trie) == 0)
def test_remove():
trie = Trie()
trie.add("abcd", "abcd")
trie.add("abc", "testing abc")
trie.add("abc", "testing abc")
trie.add("abd", "Node abd")
assert(trie.countPrefix("abc") == 2)
assert(trie.countPrefix("a") == 3)
assert(trie.frequency("abc") == 2)
assert(len(trie) == 3)
assert(trie.remove("") == None)
assert(len(trie) == 3)
assert(trie.remove("a") == None)
assert(len(trie) == 3)
assert(trie.hasWord("abc") == True)
assert(trie.remove("abc", True) == "testing abc") # force remove
assert(trie.hasWord("abc") == False)
assert(len(trie) == 2)
assert(trie.countPrefix("abc") == 1)
assert(trie.countPrefix("a") == 2)
# already removed, now it only exists as a prefix
assert(trie.remove("abc") == None)
assert(len(trie) == 2)
assert(trie.hasWord("abd") == True)
assert(trie.remove("abd") == "Node abd")
assert(trie.hasWord("abd") == False)
assert(len(trie) == 1)
assert(trie.countPrefix("abc") == 1)
assert(trie.countPrefix("a") == 1)
assert(trie.hasWord("abcd") == True)
assert(trie.remove("abcd") == "abcd")
assert(len(trie) == 0)
assert(trie.root == None)
trie.add("abcd")
trie.add("abcd")
trie.add("abcd")
assert(trie.frequency("abcd") == 3)
assert(len(trie) == 1)
assert(trie.hasPrefix("abc") == True)
assert(trie.hasWord("abcd") == True)
assert(trie.countPrefix("abc") == 1)
assert(trie.countPrefix("a") == 1)
assert(trie.remove("abcd") == None) # soft remove, reduce frequency
assert(len(trie) == 1)
assert(trie.hasWord("abcd") == True)
assert(trie.frequency("abcd") == 2)
trie.add("abcd", "what")
assert(trie.frequency("abcd") == 3)
trie.add("abc")
assert(len(trie) == 2)
assert(trie.remove("abcd", True) == "what") # remove unconditionally
assert(len(trie) == 1)
assert(trie.hasWord("abc") == True)
assert(trie.hasWord("abcd") == False)
assert(trie.remove("abc") == None) # soft remove, reduce frequency + delete because f:0
assert(len(trie) == 0)
assert(trie.root == None)
trie.add("ab")
trie.add("abcd")
assert(len(trie) == 2)
assert(trie.remove("abcd") == None)
assert(len(trie) == 1)
assert(trie.hasWord("ab") == True)
assert(trie.hasWord("abcd") == False)
assert(trie.hasPrefix("abc") == False)
assert(trie.root['a'].children['b'].children.items == None)