diff options
Diffstat (limited to 'Lib/test/test_re.py')
| -rw-r--r-- | Lib/test/test_re.py | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/Lib/test/test_re.py b/Lib/test/test_re.py index d2547d4a96..7348af3f1a 100644 --- a/Lib/test/test_re.py +++ b/Lib/test/test_re.py @@ -557,7 +557,7 @@ class ReTests(unittest.TestCase): self.assertEqual(re.match("a.*b", "a\n\nb", re.DOTALL).group(0), "a\n\nb") - def test_non_consuming(self): + def test_lookahead(self): self.assertEqual(re.match("(a(?=\s[^a]))", "a b").group(1), "a") self.assertEqual(re.match("(a(?=\s[^a]*))", "a b").group(1), "a") self.assertEqual(re.match("(a(?=\s[abc]))", "a b").group(1), "a") @@ -571,6 +571,37 @@ class ReTests(unittest.TestCase): self.assertEqual(re.match(r"(a)(?!\s\1)", "a b").group(1), "a") self.assertEqual(re.match(r"(a)(?!\s(abc|a))", "a b").group(1), "a") + # Group reference. + self.assertTrue(re.match(r'(a)b(?=\1)a', 'aba')) + self.assertIsNone(re.match(r'(a)b(?=\1)c', 'abac')) + # Named group reference. + self.assertTrue(re.match(r'(?P<g>a)b(?=(?P=g))a', 'aba')) + self.assertIsNone(re.match(r'(?P<g>a)b(?=(?P=g))c', 'abac')) + # Conditional group reference. + self.assertTrue(re.match(r'(?:(a)|(x))b(?=(?(2)x|c))c', 'abc')) + self.assertIsNone(re.match(r'(?:(a)|(x))b(?=(?(2)c|x))c', 'abc')) + self.assertTrue(re.match(r'(?:(a)|(x))b(?=(?(2)x|c))c', 'abc')) + self.assertIsNone(re.match(r'(?:(a)|(x))b(?=(?(1)b|x))c', 'abc')) + self.assertTrue(re.match(r'(?:(a)|(x))b(?=(?(1)c|x))c', 'abc')) + # Group used before defined. + self.assertTrue(re.match(r'(a)b(?=(?(2)x|c))(c)', 'abc')) + self.assertIsNone(re.match(r'(a)b(?=(?(2)b|x))(c)', 'abc')) + self.assertTrue(re.match(r'(a)b(?=(?(1)c|x))(c)', 'abc')) + + def test_lookbehind(self): + self.assertTrue(re.match(r'ab(?<=b)c', 'abc')) + self.assertIsNone(re.match(r'ab(?<=c)c', 'abc')) + self.assertIsNone(re.match(r'ab(?<!b)c', 'abc')) + self.assertTrue(re.match(r'ab(?<!c)c', 'abc')) + # Group reference. + self.assertWarns(RuntimeWarning, re.compile, r'(a)a(?<=\1)c') + # Named group reference. + self.assertWarns(RuntimeWarning, re.compile, r'(?P<g>a)a(?<=(?P=g))c') + # Conditional group reference. + self.assertWarns(RuntimeWarning, re.compile, r'(a)b(?<=(?(1)b|x))c') + # Group used before defined. + self.assertWarns(RuntimeWarning, re.compile, r'(a)b(?<=(?(2)b|x))(c)') + def test_ignore_case(self): self.assertEqual(re.match("abc", "ABC", re.I).group(0), "ABC") self.assertEqual(re.match(b"abc", b"ABC", re.I).group(0), b"ABC") |