find pattern in string using loops

import unittest

def match(pattern, string):
        """ match(pattern, searchString) returns boolean given a pattern string and a
        searchString and if the pattern string is found in the searchString then it returns true.
        Caveats: The edge case of searching for the space or ' ' always returns false.
        Otherwise known as a known bug."""
        lenPattern = len(pattern)
        lenString = len(string)
        if (lenPattern > lenString or lenPattern == 0):
                return False
        charsMatched = 0
        """ worst case scenario loops lenPattern * lenString times. """
        for i in range(0,lenString):
                for j in range(0,lenPattern):
                        if (pattern[j] == string[i]):
                                charsMatched += 1
                                if (charsMatched == lenPattern):
                                        return True
                                        break

"""
unit tests
"""
class testMatch(unittest.TestCase):
        def testPatternLongerThanSearchString(self):
                s = 'is'
                p = 'this is not'
                self.assertFalse(match(p,s))

def testPatternShorterThanSearchStringAndNotInSearchString(self):
                s = 'is'
                p = 'does not contain'
                self.assertFalse(match(p,s))

def testPatternShorterThanSearchStringAndInSearchString(self):
                s = 'this is not'
                p = 'is'
                self.assertTrue(match(p,s))

def testPatternEqualToSearchStringAndNotInSearchString(self):
                s = 'this'
                p = 'here'
                self.assertFalse(match(p,s))

def testPatternEqualToSearchStringAndInSearchString(self):
                s = 'this is a test'
                p = 'this is a test'
                self.assertTrue(match(p,s))

def testSingleCharWherePatternIsInString(self):
                s = 'a'
                p = 'a'
                self.assertTrue(match(p,s))

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

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