How can I assert in a unit test that a regex pattern occurs multiple times in a string?

Question

I have a unit test that asserts that a certain regex pattern appears in a multiline string:

import unittest

class TestStrRegex(unittest.TestCase):

    def test_pattern_matches_thrice(self):
        string = """\
        repeatedval=78
        badval=89
        # comment
        repeatedval=20
        repeatedval=8978
        """
        self.assertRegex(string, 'repeatedval=\d+')

I would like to assert that the 'repeatedval=\d+' pattern matches exactly three times in the string, something like this:

self.assertRegex(string, 'repeatedval=\d+', exact_number_of_matches=3)

But that doesn't work. Is there another way to make this assertion?

Answer 1

Use the re module directly, and assert that the result has a particular length.

def test_pattern_matches_thrice(self):
    string = """..."""
    result = re.findall(r'repeatedval=\d+', string)
    self.assertEqual(len(result), 3)