wordfreq/tests/test_chinese.py
2022-03-10 18:33:42 -05:00

121 lines
4.0 KiB
Python

from wordfreq import tokenize, word_frequency, zipf_frequency
import pytest
def test_tokens():
# Let's test on some Chinese text that has unusual combinations of
# syllables, because it is about an American vice-president.
#
# (He was the Chinese Wikipedia's featured article of the day when I
# wrote this test.)
hobart = "加勒特·霍巴特" # Garret Hobart, or "jiā lè tè huò bā tè".
# He was the sixth American vice president to die in office.
fact_simplified = "他是历史上第六位在任期内去世的美国副总统。"
fact_traditional = "他是歷史上第六位在任期內去世的美國副總統。"
# His name breaks into five pieces, with the only piece staying together
# being the one that means 'Bart'. The dot is not included as a token.
assert tokenize(hobart, "zh") == ["", "", "", "", "巴特"]
assert tokenize(fact_simplified, "zh") == [
# he / is / history / in / #6 / counter for people
"",
"",
"历史",
"",
"第六",
"",
# during / term of office / in / die
"",
"任期",
"",
"去世",
# of / U.S. / deputy / president
"",
"美国",
"",
"总统",
]
# Jieba's original tokenizer knows a lot of names, it seems.
assert tokenize(hobart, "zh", external_wordlist=True) == ["加勒特", "霍巴特"]
# We get almost the same tokens from the sentence using Jieba's own
# wordlist, but it tokenizes "in history" as two words and
# "sixth person" as one.
assert tokenize(fact_simplified, "zh", external_wordlist=True) == [
# he / is / history / in / sixth person
"",
"",
"历史",
"",
"第六位",
# during / term of office / in / die
"",
"任期",
"",
"去世",
# of / U.S. / deputy / president
"",
"美国",
"",
"总统",
]
# Check that Traditional Chinese works at all
assert word_frequency(fact_traditional, "zh") > 0
# You get the same token lengths if you look it up in Traditional Chinese,
# but the words are different
simp_tokens = tokenize(fact_simplified, "zh", include_punctuation=True)
trad_tokens = tokenize(fact_traditional, "zh", include_punctuation=True)
assert "".join(simp_tokens) == fact_simplified
assert "".join(trad_tokens) == fact_traditional
simp_lengths = [len(token) for token in simp_tokens]
trad_lengths = [len(token) for token in trad_tokens]
assert simp_lengths == trad_lengths
def test_combination():
xiexie_freq = word_frequency("谢谢", "zh") # "Thanks"
assert word_frequency("谢谢谢谢", "zh") == pytest.approx(xiexie_freq / 20, rel=0.01)
def test_alternate_codes():
# Tokenization of Chinese works when you use other language codes
# that are not equal to 'zh'.
tokens = ["谢谢", "谢谢"]
# Code with a region attached
assert tokenize("谢谢谢谢", "zh-CN") == tokens
# Over-long codes for Chinese
assert tokenize("谢谢谢谢", "chi") == tokens
assert tokenize("谢谢谢谢", "zho") == tokens
# Separate codes for Mandarin and Cantonese
assert tokenize("谢谢谢谢", "cmn") == tokens
assert tokenize("谢谢谢谢", "yue") == tokens
def test_unreasonably_long():
# This crashed earlier versions of wordfreq due to an overflow in
# exponentiation. We've now changed the sequence of operations so it
# will underflow instead.
lots_of_ls = "l" * 800
assert word_frequency(lots_of_ls, "zh") == 0.0
assert zipf_frequency(lots_of_ls, "zh") == 0.0
def test_hyphens():
# An edge case of Chinese tokenization that changed sometime around
# jieba 0.42.
tok = tokenize("--------", "zh", include_punctuation=True)
assert tok == ["-"] * 8
tok = tokenize("--------", "zh", include_punctuation=True, external_wordlist=True)
assert tok == ["--------"]