Given a phrase, count the occurrences of each word in that phrase.
For example for the input "olly olly in come free"
olly: 2
in: 1
come: 1
free: 1
Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include a message.
To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
raise Exception
, you should write:
raise Exception("Meaningful message indicating the source of the error")
To run the tests, run the appropriate command below (why they are different):
py.test word_count_test.py
pytest word_count_test.py
Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version):
python -m pytest word_count_test.py
pytest
options-v
: enable verbose output-x
: stop running tests on first failure--ff
: run failures from previous test before running other test casesFor other options, see python -m pytest -h
Note that, when trying to submit an exercise, make sure the solution is in the $EXERCISM_WORKSPACE/python/word-count
directory.
You can find your Exercism workspace by running exercism debug
and looking for the line that starts with Workspace
.
For more detailed information about running tests, code style and linting, please see the help page.
This is a classic toy problem, but we were reminded of it by seeing it in the Go Tour.
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
import unittest
from word_count import word_count
# Tests adapted from `problem-specifications//canonical-data.json` @ v1.2.0
class WordCountTest(unittest.TestCase):
def test_count_one_word(self):
self.assertEqual(
word_count('word'),
{'word': 1}
)
def test_count_one_of_each(self):
self.assertEqual(
word_count('one of each'),
{'one': 1, 'of': 1, 'each': 1}
)
def test_count_multiple_occurrences_of_a_word(self):
self.assertEqual(
word_count('one fish two fish red fish blue fish'),
{'one': 1, 'fish': 4, 'two': 1, 'red': 1, 'blue': 1}
)
def test_cramped_list(self):
self.assertEqual(
word_count('one,two,three'),
{'one': 1, 'two': 1, 'three': 1}
)
def test_expanded_list(self):
self.assertEqual(
word_count('one,\ntwo,\nthree'),
{'one': 1, 'two': 1, 'three': 1}
)
def test_ignores_punctuation(self):
self.assertEqual(
word_count('car : carpet as java : javascript!!&@$%^&'),
{'car': 1, 'carpet': 1, 'as': 1, 'java': 1, 'javascript': 1}
)
def test_include_numbers(self):
self.assertEqual(
word_count('testing 1 2 testing'),
{'testing': 2, '1': 1, '2': 1}
)
def test_normalize_case(self):
self.assertEqual(
word_count('go Go GO Stop stop'),
{'go': 3, 'stop': 2}
)
def test_apostrophes(self):
self.assertEqual(
word_count("First: don't laugh. Then: don't cry."),
{'first': 1, "don't": 2, 'laugh': 1, 'then': 1, 'cry': 1}
)
def test_quotations(self):
self.assertEqual(
word_count("Joe can't tell between 'large' and large."),
{'joe': 1, "can't": 1, 'tell': 1, 'between': 1, 'large': 2,
'and': 1}
)
def test_multiple_spaces_not_detected_as_a_word(self):
self.assertEqual(
word_count(' multiple whitespaces'),
{'multiple': 1, 'whitespaces': 1}
)
# Additional tests for this track
def test_tabs(self):
self.assertEqual(
word_count('rah rah ah ah ah\troma roma ma\tga ga oh la la\t'
'want your bad romance'),
{'rah': 2, 'ah': 3, 'roma': 2, 'ma': 1, 'ga': 2, 'oh': 1, 'la': 2,
'want': 1, 'your': 1, 'bad': 1, 'romance': 1}
)
def test_non_alphanumeric(self):
self.assertEqual(
word_count('hey,my_spacebar_is_broken.'),
{'hey': 1, 'my': 1, 'spacebar': 1, 'is': 1, 'broken': 1}
)
if __name__ == '__main__':
unittest.main()
from collections import Counter
# to be backwards compatible with the old Python 2.X
def decode_if_needed(string):
try:
return string.decode('utf-8')
except AttributeError:
return string
def replace_nonalpha_with_space(char):
return char.lower() if char.isalnum() else ' '
def word_count(text):
text = ''.join(replace_nonalpha_with_space(c) for c in decode_if_needed(text))
return Counter(text.split())
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