Source code for nltk.test.unit.test_tokenize

# -*- coding: utf-8 -*-
"""
Unit tests for nltk.tokenize.
See also nltk/test/tokenize.doctest
"""

from __future__ import unicode_literals

import unittest

from nose import SkipTest
from nose.tools import assert_equal

from nltk.tokenize import (
    punkt,
    word_tokenize,
    TweetTokenizer,
    StanfordSegmenter,
    TreebankWordTokenizer,
    SyllableTokenizer,
)


[docs]class TestTokenize(unittest.TestCase):
[docs] def test_tweet_tokenizer(self): """ Test TweetTokenizer using words with special and accented characters. """ tokenizer = TweetTokenizer(strip_handles=True, reduce_len=True) s9 = "@myke: Let's test these words: resumé España München français" tokens = tokenizer.tokenize(s9) expected = [ ':', "Let's", 'test', 'these', 'words', ':', 'resumé', 'España', 'München', 'français', ] self.assertEqual(tokens, expected)
[docs] def test_sonority_sequencing_syllable_tokenizer(self): """ Test SyllableTokenizer tokenizer. """ tokenizer = SyllableTokenizer() tokens = tokenizer.tokenize('justification') self.assertEqual(tokens, ['jus', 'ti', 'fi', 'ca', 'tion'])
[docs] def test_stanford_segmenter_arabic(self): """ Test the Stanford Word Segmenter for Arabic (default config) """ try: seg = StanfordSegmenter() seg.default_config('ar') sent = u'يبحث علم الحاسوب استخدام الحوسبة بجميع اشكالها لحل المشكلات' segmented_sent = seg.segment(sent.split()) assert segmented_sent.split() == [ 'يبحث', 'علم', 'الحاسوب', 'استخدام', 'الحوسبة', 'ب', 'جميع', 'اشكال', 'ها', 'ل', 'حل', 'المشكلات', ] except LookupError as e: raise SkipTest(str(e))
[docs] def test_stanford_segmenter_chinese(self): """ Test the Stanford Word Segmenter for Chinese (default config) """ try: seg = StanfordSegmenter() seg.default_config('zh') sent = u"这是斯坦福中文分词器测试" segmented_sent = seg.segment(sent.split()) assert segmented_sent.split() == ['这', '是', '斯坦福', '中文', '分词器', '测试'] except LookupError as e: raise SkipTest(str(e))
[docs] def test_phone_tokenizer(self): """ Test a string that resembles a phone number but contains a newline """ # Should be recognized as a phone number, albeit one with multiple spaces tokenizer = TweetTokenizer() test1 = "(393) 928 -3010" expected = ['(393) 928 -3010'] result = tokenizer.tokenize(test1) self.assertEqual(result, expected) # Due to newline, first three elements aren't part of a phone number; # fourth is test2 = "(393)\n928 -3010" expected = ['(', '393', ')', "928 -3010"] result = tokenizer.tokenize(test2) self.assertEqual(result, expected)
[docs] def test_remove_handle(self): """ Test remove_handle() from casual.py with specially crafted edge cases """ tokenizer = TweetTokenizer(strip_handles=True) # Simple example. Handles with just numbers should be allowed test1 = "@twitter hello @twi_tter_. hi @12345 @123news" expected = ['hello', '.', 'hi'] result = tokenizer.tokenize(test1) self.assertEqual(result, expected) # Handles are allowed to follow any of the following characters test2 = "@n`@n~@n(@n)@n-@n=@n+@n\\@n|@n[@n]@n{@n}@n;@n:@n'@n\"@n/@n?@n.@n,@n<@n>@n @n\n@n ñ@n.ü@n.ç@n." expected = [ '`', '~', '(', ')', '-', '=', '+', '\\', '|', '[', ']', '{', '}', ';', ':', "'", '"', '/', '?', '.', ',', '<', '>', 'ñ', '.', 'ü', '.', 'ç', '.', ] result = tokenizer.tokenize(test2) self.assertEqual(result, expected) # Handles are NOT allowed to follow any of the following characters test3 = "a@n j@n z@n A@n L@n Z@n 1@n 4@n 7@n 9@n 0@n _@n !@n @@n #@n $@n %@n &@n *@n" expected = [ 'a', '@n', 'j', '@n', 'z', '@n', 'A', '@n', 'L', '@n', 'Z', '@n', '1', '@n', '4', '@n', '7', '@n', '9', '@n', '0', '@n', '_', '@n', '!', '@n', '@', '@n', '#', '@n', '$', '@n', '%', '@n', '&', '@n', '*', '@n', ] result = tokenizer.tokenize(test3) self.assertEqual(result, expected) # Handles are allowed to precede the following characters test4 = "@n!a @n#a @n$a @n%a @n&a @n*a" expected = ['!', 'a', '#', 'a', '$', 'a', '%', 'a', '&', 'a', '*', 'a'] result = tokenizer.tokenize(test4) self.assertEqual(result, expected) # Tests interactions with special symbols and multiple @ test5 = "@n!@n @n#@n @n$@n @n%@n @n&@n @n*@n @n@n @@n @n@@n @n_@n @n7@n @nj@n" expected = [ '!', '@n', '#', '@n', '$', '@n', '%', '@n', '&', '@n', '*', '@n', '@n', '@n', '@', '@n', '@n', '@', '@n', '@n_', '@n', '@n7', '@n', '@nj', '@n', ] result = tokenizer.tokenize(test5) self.assertEqual(result, expected) # Tests that handles can have a max length of 20 test6 = "@abcdefghijklmnopqrstuvwxyz @abcdefghijklmnopqrst1234 @abcdefghijklmnopqrst_ @abcdefghijklmnopqrstendofhandle" expected = ['uvwxyz', '1234', '_', 'endofhandle'] result = tokenizer.tokenize(test6) self.assertEqual(result, expected) # Edge case where an @ comes directly after a long handle test7 = "@abcdefghijklmnopqrstu@abcde @abcdefghijklmnopqrst@abcde @abcdefghijklmnopqrst_@abcde @abcdefghijklmnopqrst5@abcde" expected = [ 'u', '@abcde', '@abcdefghijklmnopqrst', '@abcde', '_', '@abcde', '5', '@abcde', ] result = tokenizer.tokenize(test7) self.assertEqual(result, expected)
[docs] def test_treebank_span_tokenizer(self): """ Test TreebankWordTokenizer.span_tokenize function """ tokenizer = TreebankWordTokenizer() # Test case in the docstring test1 = "Good muffins cost $3.88\nin New (York). Please (buy) me\ntwo of them.\n(Thanks)." expected = [ (0, 4), (5, 12), (13, 17), (18, 19), (19, 23), (24, 26), (27, 30), (31, 32), (32, 36), (36, 37), (37, 38), (40, 46), (47, 48), (48, 51), (51, 52), (53, 55), (56, 59), (60, 62), (63, 68), (69, 70), (70, 76), (76, 77), (77, 78), ] result = list(tokenizer.span_tokenize(test1)) self.assertEqual(result, expected) # Test case with double quotation test2 = "The DUP is similar to the \"religious right\" in the United States and takes a hardline stance on social issues" expected = [ (0, 3), (4, 7), (8, 10), (11, 18), (19, 21), (22, 25), (26, 27), (27, 36), (37, 42), (42, 43), (44, 46), (47, 50), (51, 57), (58, 64), (65, 68), (69, 74), (75, 76), (77, 85), (86, 92), (93, 95), (96, 102), (103, 109), ] result = list(tokenizer.span_tokenize(test2)) self.assertEqual(result, expected) # Test case with double qoutation as well as converted quotations test3 = "The DUP is similar to the \"religious right\" in the United States and takes a ``hardline'' stance on social issues" expected = [ (0, 3), (4, 7), (8, 10), (11, 18), (19, 21), (22, 25), (26, 27), (27, 36), (37, 42), (42, 43), (44, 46), (47, 50), (51, 57), (58, 64), (65, 68), (69, 74), (75, 76), (77, 79), (79, 87), (87, 89), (90, 96), (97, 99), (100, 106), (107, 113), ] result = list(tokenizer.span_tokenize(test3)) self.assertEqual(result, expected)
[docs] def test_word_tokenize(self): """ Test word_tokenize function """ sentence = "The 'v', I've been fooled but I'll seek revenge." expected = ['The', "'", 'v', "'", ',', 'I', "'ve", 'been', 'fooled', 'but', 'I', "'ll", 'seek', 'revenge', '.'] self.assertEqual(word_tokenize(sentence), expected) sentence = "'v' 're'" expected = ["'", 'v', "'", "'re", "'"] self.assertEqual(word_tokenize(sentence), expected)
[docs] def test_punkt_pair_iter(self): test_cases = [ ('12', [('1', '2'), ('2', None)]), ('123', [('1', '2'), ('2', '3'), ('3', None)]), ('1234', [('1', '2'), ('2', '3'), ('3', '4'), ('4', None)]), ] for (test_input, expected_output) in test_cases: actual_output = [x for x in punkt._pair_iter(test_input)] assert_equal(actual_output, expected_output)
[docs] def test_punkt_pair_iter_handles_stop_iteration_exception(self): # test input to trigger StopIteration from next() it = iter([]) # call method under test and produce a generator gen = punkt._pair_iter(it) # unpack generator, ensure that no error is raised list(gen)
[docs] def test_punkt_tokenize_words_handles_stop_iteration_exception(self): obj = punkt.PunktBaseClass() class TestPunktTokenizeWordsMock: def word_tokenize(self, s): return iter([]) obj._lang_vars = TestPunktTokenizeWordsMock() # unpack generator, ensure that no error is raised list(obj._tokenize_words('test'))