trie_test.js

// Copyright 2007 The Closure Library Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS-IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

goog.provide('goog.structs.TrieTest');
goog.setTestOnly('goog.structs.TrieTest');

goog.require('goog.object');
goog.require('goog.structs');
goog.require('goog.structs.Trie');
goog.require('goog.testing.jsunit');

function makeTrie() {
  var trie = new goog.structs.Trie();
  trie.add('hello', 1);
  trie.add('hi', 'howdy');
  trie.add('', 'an empty string key');
  trie.add('empty value', '');
  trie.add('zero', 0);
  trie.add('object', {});
  trie.add('null', null);
  trie.add('hello, world', 2);
  trie.add('world', {});
  return trie;
}

function checkTrie(trie) {
  assertEquals('get, should be 1', trie.get('hello'), 1);
  assertEquals('get, should be "howdy"', trie.get('hi'), 'howdy');
  assertEquals('get, should be "an empty string key"', trie.get(''),
      'an empty string key');
  assertEquals('get, should be ""', trie.get('empty value'), '');
  assertEquals('get, should be ""', typeof trie.get('empty value'), 'string');
  assertEquals('get, should be an object', typeof trie.get('object'), 'object');
  assertEquals('get, should be 0', trie.get('zero'), 0);
  assertEquals('get "null", should be null', trie.get('null'), null);
  assertEquals('get, should be 2', trie.get('hello, world'), 2);
  assertEquals('get, should be an object', typeof trie.get('world'), 'object');
}

function testTrieFormation() {
  var t = makeTrie();
  checkTrie(t);
}

function testFailureOfMultipleAdds() {
  var t = new goog.structs.Trie();
  t.add('hello', 'testing');
  assertThrows('Error should be thrown when same key added twice.', function() {
    t.add('hello', 'test');
  });

  t = new goog.structs.Trie();
  t.add('null', null);
  assertThrows('Error should be thrown when same key added twice.', function() {
    t.add('null', 'hi!');
  });

  t = new goog.structs.Trie();
  t.add('null', 'blah');
  assertThrows('Error should be thrown when same key added twice.', function() {
    t.add('null', null);
  });
}

function testTrieClone() {
  var trieOne = makeTrie();
  var trieTwo = new goog.structs.Trie(trieOne);
  checkTrie(trieTwo);
}

function testTrieFromObject() {
  var someObject = {'hello' : 1,
    'hi' : 'howdy',
    '' : 'an empty string key',
    'empty value' : '',
    'object' : {},
    'zero' : 0,
    'null' : null,
    'hello, world' : 2,
    'world' : {}};
  var trie = new goog.structs.Trie(someObject);
  checkTrie(trie);
}

function testTrieGetValues() {
  var trie = makeTrie();
  var values = trie.getValues();
  assertTrue('getValues, should contain "howdy"',
      goog.object.contains(values, 'howdy'));
  assertTrue('getValues, should contain 1', goog.object.contains(values, 1));
  assertTrue('getValues, should contain 0', goog.object.contains(values, 0));
  assertTrue('getValues, should contain ""', goog.object.contains(values, ''));
  assertTrue('getValues, should contain null',
      goog.object.contains(values, null));
  assertEquals('goog.structs.getCount(getValues()) should be 9',
      goog.structs.getCount(values), 9);
}

function testTrieGetKeys() {
  var trie = makeTrie();
  var keys = trie.getKeys();
  assertTrue('getKeys, should contain "hello"',
      goog.object.contains(keys, 'hello'));
  assertTrue('getKeys, should contain "empty value"',
      goog.object.contains(keys, 'empty value'));
  assertTrue('getKeys, should contain ""', goog.object.contains(keys, ''));
  assertTrue('getKeys, should contain "zero"',
      goog.object.contains(keys, 'zero'));
  assertEquals('goog.structs.getCount(getKeys()) should be 9',
      goog.structs.getCount(keys), 9);
}


function testTrieCount() {
  var trieOne = makeTrie();
  var trieTwo = new goog.structs.Trie();
  assertEquals('count, should be 9', trieOne.getCount(), 9);
  assertEquals('count, should be 0', trieTwo.getCount(), 0);
}

function testRemoveKeyFromTrie() {
  var trie = new goog.structs.Trie();
  trie.add('key1', 'value1');
  trie.add('key2', 'value2');
  trie.add('ke', 'value3');
  trie.add('zero', 0);
  trie.remove('key2');
  assertEquals('get "key1", should be "value1"', trie.get('key1'), 'value1');
  assertUndefined('get "key2", should be undefined', trie.get('key2'));
  trie.remove('zero');
  assertUndefined('get "zero", should be undefined', trie.get('zero'));
  trie.remove('ke');
  assertUndefined('get "ke", should be undefined', trie.get('ke'));
  assertEquals('get "key1", should be "value1"', trie.get('key1'), 'value1');
  trie.add('a', 'value4');
  assertTrue('testing internal structure, a should be a child',
      'a' in trie.childNodes_);
  trie.remove('a');
  assertFalse('testing internal structure, a should no longer be a child',
      'a' in trie.childNodes_);

  trie.add('xyza', 'value');
  trie.remove('xyza', 'value');
  assertFalse('Should not have "x"', 'x' in trie.childNodes_);

  trie.add('xyza', null);
  assertTrue('Should have "x"', 'x' in trie.childNodes_);
  trie.remove('xyza');
  assertFalse('Should not have "x"', 'x' in trie.childNodes_);

  trie.add('xyza', 'value');
  trie.add('xb', 'value');
  trie.remove('xyza');
  assertTrue('get "x" should be defined', 'x' in trie.childNodes_);
  assertFalse('get "y" should be undefined',
      'y' in trie.childNodes_['x'].childNodes_);

  trie.add('akey', 'value1');
  trie.add('akey1', 'value2');
  trie.remove('akey1');
  assertEquals('get "akey", should be "value1"', 'value1', trie.get('akey'));
  assertUndefined('get "akey1", should be undefined', trie.get('akey1'));
}

function testRemoveKeyFromTrieWithNulls() {
  var trie = new goog.structs.Trie();
  trie.add('key1', null);
  trie.add('key2', 'value2');
  trie.add('ke', 'value3');
  trie.add('zero', 0);
  trie.remove('key2');
  assertEquals('get "key1", should be null', trie.get('key1'), null);
  assertUndefined('get "key2", should be undefined', trie.get('key2'));
  trie.remove('zero');
  assertUndefined('get "zero", should be undefined', trie.get('zero'));
  trie.remove('ke');
  assertUndefined('get "ke", should be undefined', trie.get('ke'));
  assertEquals('get "key1", should be null', trie.get('key1'), null);
  trie.add('a', 'value4');
  assertTrue('testing internal structure, a should be a child',
      'a' in trie.childNodes_);
  trie.remove('a');
  assertFalse('testing internal structure, a should no longer be a child',
      'a' in trie.childNodes_);

  trie.add('xyza', null);
  trie.add('xb', 'value');
  trie.remove('xyza');
  assertTrue('Should have "x"', 'x' in trie.childNodes_);
  assertFalse('Should not have "y"',
      'y' in trie.childNodes_['x'].childNodes_);
}

function testRemoveKeyException() {
  var trie = new goog.structs.Trie();
  trie.add('abcdefg', 'value');
  trie.add('abcz', 'value');
  trie.add('abc', 'value');

  assertThrows('Remove should throw an error on removal of non-existent key',
      function() {
        trie.remove('abcdefge');
      });
}

function testTrieIsEmpty() {
  var trieOne = new goog.structs.Trie();
  var trieTwo = makeTrie();
  assertTrue('isEmpty, should be empty', trieOne.isEmpty());
  assertFalse('isEmpty, should not be empty', trieTwo.isEmpty());
  trieOne.add('', 1);
  assertFalse('isEmpty, should not be empty', trieTwo.isEmpty());
  trieOne.remove('');
  assertTrue('isEmpty, should be empty', trieOne.isEmpty());
  trieOne.add('', 1);
  trieOne.add('a', 1);
  trieOne.remove('a');
  assertFalse('isEmpty, should not be empty', trieOne.isEmpty());
  trieOne.remove('');
  assertTrue('isEmpty, should be empty', trieOne.isEmpty());
  trieOne.add('', 1);
  trieOne.add('a', 1);
  trieOne.remove('');
  assertFalse('isEmpty, should not be empty', trieOne.isEmpty());
  trieOne.remove('a');
  assertTrue('isEmpty, should be empty', trieOne.isEmpty());
}

function testTrieClear() {
  var trie = new goog.structs.Trie();
  trie.add('key1', 'value1');
  trie.add('key2', 'value2');
  trie.add('key3', null);
  trie.clear();
  assertUndefined('get key1, should be undefined', trie.get('key1'));
  assertUndefined('get key2, should be undefined', trie.get('key2'));
  assertUndefined('get key3, should be undefined', trie.get('key3'));
}

function testTrieContainsKey() {
  var trie = makeTrie();
  assertTrue('containsKey, should contain "hello"', trie.containsKey('hello'));
  assertTrue('containsKey, should contain "hi"', trie.containsKey('hi'));
  assertTrue('containsKey, should contain ""', trie.containsKey(''));
  assertTrue('containsKey, should contain "empty value"',
      trie.containsKey('empty value'));
  assertTrue('containsKey, should contain "object"',
      trie.containsKey('object'));
  assertTrue('containsKey, should contain "zero"', trie.containsKey('zero'));
  assertTrue('containsKey, should contain "null"', trie.containsKey('null'));
  assertFalse('containsKey, should not contain "blah"',
      trie.containsKey('blah'));
  trie.remove('');
  trie.remove('hi');
  trie.remove('zero');
  trie.remove('null');
  assertFalse('containsKey, should not contain "zero"',
      trie.containsKey('zero'));
  assertFalse('containsKey, should not contain ""', trie.containsKey(''));
  assertFalse('containsKey, should not contain "hi"', trie.containsKey('hi'));
  assertFalse('containsKey, should not contain "null"',
      trie.containsKey('null'));
}

function testTrieContainsPrefix() {

  // Empty trie.
  var trie = new goog.structs.Trie();
  assertFalse('containsPrefix, should not contain ""', trie.containsPrefix(''));
  assertFalse('containsPrefix, should not contain "any"',
      trie.containsPrefix('any'));
  trie.add('key', 'value');
  assertTrue('containsPrefix, should contain ""', trie.containsPrefix(''));

  // Non-empty trie.
  trie = makeTrie();
  assertTrue('containsPrefix, should contain ""', trie.containsPrefix(''));
  assertFalse('containsPrefix, should not contain "blah"',
      trie.containsPrefix('blah'));
  assertTrue('containsPrefix, should contain "h"', trie.containsPrefix('h'));
  assertTrue('containsPrefix, should contain "hello"',
      trie.containsPrefix('hello'));
  assertTrue('containsPrefix, should contain "hello, world"',
      trie.containsPrefix('hello, world'));
  assertFalse('containsPrefix, should not contain "hello, world!"',
      trie.containsPrefix('hello, world!'));
  assertTrue('containsPrefix, should contain "nu"',
      trie.containsPrefix('nu'));
  assertTrue('containsPrefix, should contain "null"',
      trie.containsPrefix('null'));
  assertTrue('containsPrefix, should contain "empty value"',
      trie.containsPrefix('empty value'));

  // Remove nodes.
  trie.remove('');
  assertTrue('containsPrefix, should contain ""', trie.containsPrefix(''));
  trie.remove('hi');
  assertTrue('containsPrefix, should contain "h"', trie.containsPrefix('h'));
  assertFalse('containsPrefix, should not contain "hi"',
      trie.containsPrefix('hi'));
  trie.remove('hello');
  trie.remove('hello, world');
  assertFalse('containsPrefix, should not contain "h"',
      trie.containsPrefix('h'));
  assertFalse('containsPrefix, should not contain "hello"',
      trie.containsPrefix('hello'));

  // Remove all nodes.
  trie.remove('empty value');
  trie.remove('zero');
  trie.remove('object');
  trie.remove('null');
  trie.remove('world');
  assertFalse('containsPrefix, should not contain ""',
      trie.containsPrefix(''));
  assertFalse('containsPrefix, should not contain "h"',
      trie.containsPrefix('h'));
  assertFalse('containsPrefix, should not contain "hi"',
      trie.containsPrefix('hi'));

  // Add some new nodes.
  trie.add('hi', 'value');
  trie.add('null', 'value');
  assertTrue('containsPrefix, should contain ""', trie.containsPrefix(''));
  assertTrue('containsPrefix, should contain "h"', trie.containsPrefix('h'));
  assertTrue('containsPrefix, should contain "hi"', trie.containsPrefix('hi'));
  assertFalse('containsPrefix, should not contain "hello"',
      trie.containsPrefix('hello'));
  assertFalse('containsPrefix, should not contain "zero"',
      trie.containsPrefix('zero'));

  // Clear the trie.
  trie.clear();
  assertFalse('containsPrefix, should not contain ""',
      trie.containsPrefix(''));
  assertFalse('containsPrefix, should not contain "h"',
      trie.containsPrefix('h'));
  assertFalse('containsPrefix, should not contain "hi"',
      trie.containsPrefix('hi'));
}

function testTrieContainsValue() {
  var trie = makeTrie();
  assertTrue('containsValue, should be true, should contain 1',
      trie.containsValue(1));
  assertTrue('containsValue, should be true, should contain "howdy"',
      trie.containsValue('howdy'));
  assertTrue('containsValue, should be true, should contain ""',
      trie.containsValue(''));
  assertTrue('containsValue, should be true, should contain 0',
      trie.containsValue(0));
  assertTrue('containsValue, should be true, should contain null',
      trie.containsValue(null));
  assertTrue('containsValue, should be true, should ' +
      'contain "an empty string key"',
      trie.containsValue('an empty string key'));
  assertFalse('containsValue, should be false, should not contain "blah"',
      trie.containsValue('blah'));
  trie.remove('empty value');
  trie.remove('zero');
  assertFalse('containsValue, should be false, should not contain 0',
      trie.containsValue(0));
  assertFalse('containsValue, should be false, should not contain ""',
      trie.containsValue(''));
}

function testTrieHandlingOfEmptyStrings() {
  var trie = new goog.structs.Trie();
  assertEquals('get, should be undefined', trie.get(''), undefined);
  assertFalse('containsValue, should be false', trie.containsValue(''));
  assertFalse('containsKey, should be false', trie.containsKey(''));
  trie.add('', 'test');
  trie.add('test2', '');
  assertTrue('containsValue, should be true', trie.containsValue(''));
  assertTrue('containsKey, should be true', trie.containsKey(''));
  assertEquals('get, should be "test"', trie.get(''), 'test');
  assertEquals('get, should be ""', trie.get('test2'), '');
  trie.remove('');
  trie.remove('test2');
  assertEquals('get, should be undefined', trie.get(''), undefined);
  assertFalse('containsValue, should be false', trie.containsValue(''));
  assertFalse('containsKey, should be false', trie.containsKey(''));
}

function testPrefixOptionOnGetKeys() {
  var trie = new goog.structs.Trie();
  trie.add('abcdefg', 'one');
  trie.add('abcdefghijk', 'two');
  trie.add('abcde', 'three');
  trie.add('abcq', null);
  trie.add('abc', 'four');
  trie.add('xyz', 'five');
  assertEquals('getKeys, should be 1', trie.getKeys('xy').length, 1);
  assertEquals('getKeys, should be 1', trie.getKeys('xyz').length, 1);
  assertEquals('getKeys, should be 1', trie.getKeys('x').length, 1);
  assertEquals('getKeys, should be 4', trie.getKeys('abc').length, 5);
  assertEquals('getKeys, should be 2', trie.getKeys('abcdef').length, 2);
  assertEquals('getKeys, should be 0', trie.getKeys('abcdefgi').length, 0);
}

function testGetKeyAndPrefixes() {
  var trie = makeTrie();
  // Note: trie has one of its keys as ''
  assertEquals('getKeyAndPrefixes, should be 2',
               2,
               goog.object.getCount(trie.getKeyAndPrefixes('world')));
  assertEquals('getKeyAndPrefixes, should be 2',
               2,
               goog.object.getCount(trie.getKeyAndPrefixes('hello')));
  assertEquals('getKeyAndPrefixes, should be 2',
               2,
               goog.object.getCount(trie.getKeyAndPrefixes('hello,')));
  assertEquals('getKeyAndPrefixes, should be 3',
               3,
               goog.object.getCount(trie.getKeyAndPrefixes('hello, world')));
  assertEquals('getKeyAndPrefixes, should be 1',
               1,
               goog.object.getCount(trie.getKeyAndPrefixes('hell')));
}

function testGetKeyAndPrefixesStartIndex() {
  var trie = new goog.structs.Trie();
  trie.add('abcdefg', 'one');
  trie.add('bcdefg', 'two');
  trie.add('abcdefghijk', 'three');
  trie.add('abcde', 'four');
  trie.add('abcq', null);
  trie.add('q', null);
  trie.add('abc', 'five');
  trie.add('xyz', 'six');
  assertEquals('getKeyAndPrefixes, should be 3',
               3,
               goog.object.getCount(trie.getKeyAndPrefixes('abcdefg', 0)));
  assertEquals('getKeyAndPrefixes, should be 1',
               1,
               goog.object.getCount(trie.getKeyAndPrefixes('abcdefg', 1)));
  assertEquals('getKeyAndPrefixes, should be 1',
               1,
               goog.object.getCount(trie.getKeyAndPrefixes('abcq', 3)));
  assertEquals('getKeyAndPrefixes, should be 0',
               0,
               goog.object.getCount(trie.getKeyAndPrefixes('abcd', 3)));
}