Issue #3665: \u and \U escapes are now supported in unicode regular expressions.

Patch by Serhiy Storchaka.
This commit is contained in:
Antoine Pitrou 2012-06-23 13:29:19 +02:00
parent c9aa8425c4
commit 463badf06c
4 changed files with 144 additions and 34 deletions

View File

@ -414,17 +414,24 @@ Most of the standard escapes supported by Python string literals are also
accepted by the regular expression parser::
\a \b \f \n
\r \t \v \x
\\
\r \t \u \U
\v \x \\
(Note that ``\b`` is used to represent word boundaries, and means "backspace"
only inside character classes.)
``'\u'`` and ``'\U'`` escape sequences are only recognized in Unicode
patterns. In bytes patterns they are not treated specially.
Octal escapes are included in a limited form. If the first digit is a 0, or if
there are three octal digits, it is considered an octal escape. Otherwise, it is
a group reference. As for string literals, octal escapes are always at most
three digits in length.
.. versionchanged:: 3.3
The ``'\u'`` and ``'\U'`` escape sequences have been added.
.. _contents-of-module-re:

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@ -177,6 +177,7 @@ class SubPattern:
class Tokenizer:
def __init__(self, string):
self.istext = isinstance(string, str)
self.string = string
self.index = 0
self.__next()
@ -187,14 +188,14 @@ class Tokenizer:
char = self.string[self.index:self.index+1]
# Special case for the str8, since indexing returns a integer
# XXX This is only needed for test_bug_926075 in test_re.py
if char and isinstance(char, bytes):
if char and not self.istext:
char = chr(char[0])
if char == "\\":
try:
c = self.string[self.index + 1]
except IndexError:
raise error("bogus escape (end of line)")
if isinstance(self.string, bytes):
if not self.istext:
c = chr(c)
char = char + c
self.index = self.index + len(char)
@ -209,6 +210,15 @@ class Tokenizer:
this = self.next
self.__next()
return this
def getwhile(self, n, charset):
result = ''
for _ in range(n):
c = self.next
if c not in charset:
break
result += c
self.__next()
return result
def tell(self):
return self.index, self.next
def seek(self, index):
@ -241,20 +251,30 @@ def _class_escape(source, escape):
c = escape[1:2]
if c == "x":
# hexadecimal escape (exactly two digits)
while source.next in HEXDIGITS and len(escape) < 4:
escape = escape + source.get()
escape = escape[2:]
if len(escape) != 2:
raise error("bogus escape: %s" % repr("\\" + escape))
return LITERAL, int(escape, 16) & 0xff
escape += source.getwhile(2, HEXDIGITS)
if len(escape) != 4:
raise ValueError
return LITERAL, int(escape[2:], 16) & 0xff
elif c == "u" and source.istext:
# unicode escape (exactly four digits)
escape += source.getwhile(4, HEXDIGITS)
if len(escape) != 6:
raise ValueError
return LITERAL, int(escape[2:], 16)
elif c == "U" and source.istext:
# unicode escape (exactly eight digits)
escape += source.getwhile(8, HEXDIGITS)
if len(escape) != 10:
raise ValueError
c = int(escape[2:], 16)
chr(c) # raise ValueError for invalid code
return LITERAL, c
elif c in OCTDIGITS:
# octal escape (up to three digits)
while source.next in OCTDIGITS and len(escape) < 4:
escape = escape + source.get()
escape = escape[1:]
return LITERAL, int(escape, 8) & 0xff
escape += source.getwhile(2, OCTDIGITS)
return LITERAL, int(escape[1:], 8) & 0xff
elif c in DIGITS:
raise error("bogus escape: %s" % repr(escape))
raise ValueError
if len(escape) == 2:
return LITERAL, ord(escape[1])
except ValueError:
@ -273,15 +293,27 @@ def _escape(source, escape, state):
c = escape[1:2]
if c == "x":
# hexadecimal escape
while source.next in HEXDIGITS and len(escape) < 4:
escape = escape + source.get()
escape += source.getwhile(2, HEXDIGITS)
if len(escape) != 4:
raise ValueError
return LITERAL, int(escape[2:], 16) & 0xff
elif c == "u" and source.istext:
# unicode escape (exactly four digits)
escape += source.getwhile(4, HEXDIGITS)
if len(escape) != 6:
raise ValueError
return LITERAL, int(escape[2:], 16)
elif c == "U" and source.istext:
# unicode escape (exactly eight digits)
escape += source.getwhile(8, HEXDIGITS)
if len(escape) != 10:
raise ValueError
c = int(escape[2:], 16)
chr(c) # raise ValueError for invalid code
return LITERAL, c
elif c == "0":
# octal escape
while source.next in OCTDIGITS and len(escape) < 4:
escape = escape + source.get()
escape += source.getwhile(2, OCTDIGITS)
return LITERAL, int(escape[1:], 8) & 0xff
elif c in DIGITS:
# octal escape *or* decimal group reference (sigh)

View File

@ -526,24 +526,92 @@ class ReTests(unittest.TestCase):
self.assertNotEqual(re.compile('^pattern$', flag), None)
def test_sre_character_literals(self):
for i in [0, 8, 16, 32, 64, 127, 128, 255]:
self.assertNotEqual(re.match(r"\%03o" % i, chr(i)), None)
self.assertNotEqual(re.match(r"\%03o0" % i, chr(i)+"0"), None)
self.assertNotEqual(re.match(r"\%03o8" % i, chr(i)+"8"), None)
self.assertNotEqual(re.match(r"\x%02x" % i, chr(i)), None)
self.assertNotEqual(re.match(r"\x%02x0" % i, chr(i)+"0"), None)
self.assertNotEqual(re.match(r"\x%02xz" % i, chr(i)+"z"), None)
self.assertRaises(re.error, re.match, "\911", "")
for i in [0, 8, 16, 32, 64, 127, 128, 255, 256, 0xFFFF, 0x10000, 0x10FFFF]:
if i < 256:
self.assertIsNotNone(re.match(r"\%03o" % i, chr(i)))
self.assertIsNotNone(re.match(r"\%03o0" % i, chr(i)+"0"))
self.assertIsNotNone(re.match(r"\%03o8" % i, chr(i)+"8"))
self.assertIsNotNone(re.match(r"\x%02x" % i, chr(i)))
self.assertIsNotNone(re.match(r"\x%02x0" % i, chr(i)+"0"))
self.assertIsNotNone(re.match(r"\x%02xz" % i, chr(i)+"z"))
if i < 0x10000:
self.assertIsNotNone(re.match(r"\u%04x" % i, chr(i)))
self.assertIsNotNone(re.match(r"\u%04x0" % i, chr(i)+"0"))
self.assertIsNotNone(re.match(r"\u%04xz" % i, chr(i)+"z"))
self.assertIsNotNone(re.match(r"\U%08x" % i, chr(i)))
self.assertIsNotNone(re.match(r"\U%08x0" % i, chr(i)+"0"))
self.assertIsNotNone(re.match(r"\U%08xz" % i, chr(i)+"z"))
self.assertIsNotNone(re.match(r"\0", "\000"))
self.assertIsNotNone(re.match(r"\08", "\0008"))
self.assertIsNotNone(re.match(r"\01", "\001"))
self.assertIsNotNone(re.match(r"\018", "\0018"))
self.assertIsNotNone(re.match(r"\567", chr(0o167)))
self.assertRaises(re.error, re.match, r"\911", "")
self.assertRaises(re.error, re.match, r"\x1", "")
self.assertRaises(re.error, re.match, r"\x1z", "")
self.assertRaises(re.error, re.match, r"\u123", "")
self.assertRaises(re.error, re.match, r"\u123z", "")
self.assertRaises(re.error, re.match, r"\U0001234", "")
self.assertRaises(re.error, re.match, r"\U0001234z", "")
self.assertRaises(re.error, re.match, r"\U00110000", "")
def test_sre_character_class_literals(self):
for i in [0, 8, 16, 32, 64, 127, 128, 255, 256, 0xFFFF, 0x10000, 0x10FFFF]:
if i < 256:
self.assertIsNotNone(re.match(r"[\%o]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\%o8]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\%03o]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\%03o0]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\%03o8]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\x%02x]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\x%02x0]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\x%02xz]" % i, chr(i)))
if i < 0x10000:
self.assertIsNotNone(re.match(r"[\u%04x]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\u%04x0]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\u%04xz]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\U%08x]" % i, chr(i)))
self.assertIsNotNone(re.match(r"[\U%08x0]" % i, chr(i)+"0"))
self.assertIsNotNone(re.match(r"[\U%08xz]" % i, chr(i)+"z"))
self.assertRaises(re.error, re.match, r"[\911]", "")
self.assertRaises(re.error, re.match, r"[\x1z]", "")
self.assertRaises(re.error, re.match, r"[\u123z]", "")
self.assertRaises(re.error, re.match, r"[\U0001234z]", "")
self.assertRaises(re.error, re.match, r"[\U00110000]", "")
def test_sre_byte_literals(self):
for i in [0, 8, 16, 32, 64, 127, 128, 255]:
self.assertNotEqual(re.match(r"[\%03o]" % i, chr(i)), None)
self.assertNotEqual(re.match(r"[\%03o0]" % i, chr(i)), None)
self.assertNotEqual(re.match(r"[\%03o8]" % i, chr(i)), None)
self.assertNotEqual(re.match(r"[\x%02x]" % i, chr(i)), None)
self.assertNotEqual(re.match(r"[\x%02x0]" % i, chr(i)), None)
self.assertNotEqual(re.match(r"[\x%02xz]" % i, chr(i)), None)
self.assertRaises(re.error, re.match, "[\911]", "")
self.assertIsNotNone(re.match((r"\%03o" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"\%03o0" % i).encode(), bytes([i])+b"0"))
self.assertIsNotNone(re.match((r"\%03o8" % i).encode(), bytes([i])+b"8"))
self.assertIsNotNone(re.match((r"\x%02x" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"\x%02x0" % i).encode(), bytes([i])+b"0"))
self.assertIsNotNone(re.match((r"\x%02xz" % i).encode(), bytes([i])+b"z"))
self.assertIsNotNone(re.match(br"\u", b'u'))
self.assertIsNotNone(re.match(br"\U", b'U'))
self.assertIsNotNone(re.match(br"\0", b"\000"))
self.assertIsNotNone(re.match(br"\08", b"\0008"))
self.assertIsNotNone(re.match(br"\01", b"\001"))
self.assertIsNotNone(re.match(br"\018", b"\0018"))
self.assertIsNotNone(re.match(br"\567", bytes([0o167])))
self.assertRaises(re.error, re.match, br"\911", b"")
self.assertRaises(re.error, re.match, br"\x1", b"")
self.assertRaises(re.error, re.match, br"\x1z", b"")
def test_sre_byte_class_literals(self):
for i in [0, 8, 16, 32, 64, 127, 128, 255]:
self.assertIsNotNone(re.match((r"[\%o]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\%o8]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\%03o]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\%03o0]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\%03o8]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\x%02x]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\x%02x0]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match((r"[\x%02xz]" % i).encode(), bytes([i])))
self.assertIsNotNone(re.match(br"[\u]", b'u'))
self.assertIsNotNone(re.match(br"[\U]", b'U'))
self.assertRaises(re.error, re.match, br"[\911]", "")
self.assertRaises(re.error, re.match, br"[\x1z]", "")
def test_bug_113254(self):
self.assertEqual(re.match(r'(a)|(b)', 'b').start(1), -1)

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@ -40,6 +40,9 @@ Core and Builtins
Library
-------
- Issue #3665: \u and \U escapes are now supported in unicode regular
expressions. Patch by Serhiy Storchaka.
- Issue #15153: Added inspect.getgeneratorlocals to simplify white box
testing of generator state updates