def test_searchengine_calculate_idf():
'''
Tests the term_frequency function.
'''
test = SearchEngine(DIRECTORY)
assert_equals(0, test._calculate_idf('croissant'))
assert_equals(0, test._calculate_idf('i'))
assert_equals(math.log(1.5), test._calculate_idf('chocolate'))
assert_equals(math.log(3), test._calculate_idf('apple'))
def test_search_engine_1():
test = SearchEngine('test_dir1')
# Tests small number of words
assert_equals('test_dir1', test._dir)
assert_equals(5, test._num_docs)
assert_equals(0, test._calculate_idf('Cat'))
assert_equals(.223, test._calculate_idf('I'))
assert_equals(1.609, test._calculate_idf('dogs'))
assert_equals(['doc3.txt'], test.search('dogs'))
assert_equals(['doc3.txt'], test.search('dogs'))
assert_equals(['doc4.txt', 'doc1.txt'], test.search('eat'))
assert_equals(['doc4.txt', 'doc3.txt', 'doc1.txt'],
test.search('eat dogs'))
def test_search_engine_3():
test = SearchEngine('test_dir3')
# Tests Empty Directory
assert_equals(1, test._num_docs)
assert_equals({}, test._docs)
assert_equals(0, test._calculate_idf('Samsung'))
assert_equals(None, test.search('Samsung'))
def test_search_engine_2():
test = SearchEngine('test_dir2')
# Tests large number of words
assert_equals(4, test._num_docs)
assert_equals(.287, test._calculate_idf('Samsung'))
assert_equals(['ChromeBook.html', 'att.html', 'facebook.html'],
test.search('Samsung'))
assert_equals(['ChromeBook.html', 'att.html', 'facebook.html'],
test.search('Samsung companies!'))
assert_equals(None, test.search('adksamfk'))
def test_search_engine_class():
"""
This function tests the correctness of the functions
implemented in SearchEngine class.
"""
search_engine = SearchEngine('test-files')
assert_equals(math.log(3/2), search_engine._calculate_idf('dogs'))
fir_search = search_engine.search('dogs')
assert_equals(['test-files/doc3.txt', 'test-files/doc1.txt'], fir_search)
sec_search = search_engine.search('Cats very cute')
assert_equals(['test-files/doc2.txt'], sec_search)
thir_search = search_engine.search('happy')
assert_equals(None, thir_search)
