tokenization_test.py

# coding=utf-8
# Copyright 2018 The Google AI Language Team Authors.
#
# 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.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import os
import unittest
from io import open

from pytorch_pretrained_bert.tokenization import (BertTokenizer, BasicTokenizer, WordpieceTokenizer,
                                                  _is_whitespace, _is_control, _is_punctuation)


class TokenizationTest(unittest.TestCase):

    def test_full_tokenizer(self):
        vocab_tokens = [
            "[UNK]", "[CLS]", "[SEP]", "want", "##want", "##ed", "wa", "un", "runn",
            "##ing", ","
        ]
        with open("/tmp/bert_tokenizer_test.txt", "w", encoding='utf-8') as vocab_writer:
            vocab_writer.write("".join([x + "\n" for x in vocab_tokens]))

            vocab_file = vocab_writer.name

        tokenizer = BertTokenizer(vocab_file)
        os.remove(vocab_file)

        tokens = tokenizer.tokenize(u"UNwant\u00E9d,running")
        self.assertListEqual(tokens, ["un", "##want", "##ed", ",", "runn", "##ing"])

        self.assertListEqual(
            tokenizer.convert_tokens_to_ids(tokens), [7, 4, 5, 10, 8, 9])

    def test_full_tokenizer_raises_error_for_long_sequences(self):
        vocab_tokens = [
            "[UNK]", "[CLS]", "[SEP]", "want", "##want", "##ed", "wa", "un", "runn",
            "##ing", ","
        ]
        with open("/tmp/bert_tokenizer_test.txt", "w", encoding='utf-8') as vocab_writer:
            vocab_writer.write("".join([x + "\n" for x in vocab_tokens]))
            vocab_file = vocab_writer.name

        tokenizer = BertTokenizer(vocab_file, max_len=10)
        os.remove(vocab_file)
        tokens = tokenizer.tokenize(u"the cat sat on the mat in the summer time")
        indices = tokenizer.convert_tokens_to_ids(tokens)
        self.assertListEqual(indices, [0 for _ in range(10)])

        tokens = tokenizer.tokenize(u"the cat sat on the mat in the summer time .")
        self.assertRaises(ValueError, tokenizer.convert_tokens_to_ids, tokens)

    def test_chinese(self):
        tokenizer = BasicTokenizer()

        self.assertListEqual(
            tokenizer.tokenize(u"ah\u535A\u63A8zz"),
            [u"ah", u"\u535A", u"\u63A8", u"zz"])

    def test_basic_tokenizer_lower(self):
        tokenizer = BasicTokenizer(do_lower_case=True)

        self.assertListEqual(
            tokenizer.tokenize(u" \tHeLLo!how  \n Are yoU?  "),
            ["hello", "!", "how", "are", "you", "?"])
        self.assertListEqual(tokenizer.tokenize(u"H\u00E9llo"), ["hello"])

    def test_basic_tokenizer_no_lower(self):
        tokenizer = BasicTokenizer(do_lower_case=False)

        self.assertListEqual(
            tokenizer.tokenize(u" \tHeLLo!how  \n Are yoU?  "),
            ["HeLLo", "!", "how", "Are", "yoU", "?"])

    def test_wordpiece_tokenizer(self):
        vocab_tokens = [
            "[UNK]", "[CLS]", "[SEP]", "want", "##want", "##ed", "wa", "un", "runn",
            "##ing"
        ]

        vocab = {}
        for (i, token) in enumerate(vocab_tokens):
            vocab[token] = i
        tokenizer = WordpieceTokenizer(vocab=vocab)

        self.assertListEqual(tokenizer.tokenize(""), [])

        self.assertListEqual(
            tokenizer.tokenize("unwanted running"),
            ["un", "##want", "##ed", "runn", "##ing"])

        self.assertListEqual(
            tokenizer.tokenize("unwantedX running"), ["[UNK]", "runn", "##ing"])

    def test_is_whitespace(self):
        self.assertTrue(_is_whitespace(u" "))
        self.assertTrue(_is_whitespace(u"\t"))
        self.assertTrue(_is_whitespace(u"\r"))
        self.assertTrue(_is_whitespace(u"\n"))
        self.assertTrue(_is_whitespace(u"\u00A0"))

        self.assertFalse(_is_whitespace(u"A"))
        self.assertFalse(_is_whitespace(u"-"))

    def test_is_control(self):
        self.assertTrue(_is_control(u"\u0005"))

        self.assertFalse(_is_control(u"A"))
        self.assertFalse(_is_control(u" "))
        self.assertFalse(_is_control(u"\t"))
        self.assertFalse(_is_control(u"\r"))

    def test_is_punctuation(self):
        self.assertTrue(_is_punctuation(u"-"))
        self.assertTrue(_is_punctuation(u"$"))
        self.assertTrue(_is_punctuation(u"`"))
        self.assertTrue(_is_punctuation(u"."))

        self.assertFalse(_is_punctuation(u"A"))
        self.assertFalse(_is_punctuation(u" "))


if __name__ == '__main__':
    unittest.main()