Issue #27030: Unknown escapes consisting of ``'\'`` and ASCII letter in

regular expressions now are errors.
This commit is contained in:
Serhiy Storchaka 2016-06-11 19:15:00 +03:00
parent d35bf03284
commit 9bd85b83f6
4 changed files with 32 additions and 84 deletions

View File

@ -317,8 +317,9 @@ The special characters are:
The special sequences consist of ``'\'`` and a character from the list below.
If the ordinary character is not on the list, then the resulting RE will match
the second character. For example, ``\$`` matches the character ``'$'``.
If the ordinary character is not ASCII digit or ASCII letter, then the
resulting RE will match the second character. For example, ``\$`` matches the
character ``'$'``.
``\number``
Matches the contents of the group of the same number. Groups are numbered
@ -438,9 +439,8 @@ three digits in length.
.. versionchanged:: 3.3
The ``'\u'`` and ``'\U'`` escape sequences have been added.
.. deprecated-removed:: 3.5 3.6
Unknown escapes consist of ``'\'`` and ASCII letter now raise a
deprecation warning and will be forbidden in Python 3.6.
.. versionchanged:: 3.6
Unknown escapes consisting of ``'\'`` and ASCII letter now are errors.
.. seealso::
@ -528,11 +528,11 @@ form.
current locale. The use of this flag is discouraged as the locale mechanism
is very unreliable, and it only handles one "culture" at a time anyway;
you should use Unicode matching instead, which is the default in Python 3
for Unicode (str) patterns. This flag makes sense only with bytes patterns.
for Unicode (str) patterns. This flag can be used only with bytes patterns.
.. deprecated-removed:: 3.5 3.6
Deprecated the use of :const:`re.LOCALE` with string patterns or
:const:`re.ASCII`.
.. versionchanged:: 3.6
:const:`re.LOCALE` can be used only with bytes patterns and is
not compatible with :const:`re.ASCII`.
.. data:: M
@ -738,9 +738,8 @@ form.
.. versionchanged:: 3.5
Unmatched groups are replaced with an empty string.
.. deprecated-removed:: 3.5 3.6
Unknown escapes consist of ``'\'`` and ASCII letter now raise a
deprecation warning and will be forbidden in Python 3.6.
.. versionchanged:: 3.6
Unknown escapes consisting of ``'\'`` and ASCII letter now are errors.
.. function:: subn(pattern, repl, string, count=0, flags=0)

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@ -282,33 +282,6 @@ class Tokenizer:
def error(self, msg, offset=0):
return error(msg, self.string, self.tell() - offset)
# The following three functions are not used in this module anymore, but we keep
# them here (with DeprecationWarnings) for backwards compatibility.
def isident(char):
import warnings
warnings.warn('sre_parse.isident() will be removed in 3.5',
DeprecationWarning, stacklevel=2)
return "a" <= char <= "z" or "A" <= char <= "Z" or char == "_"
def isdigit(char):
import warnings
warnings.warn('sre_parse.isdigit() will be removed in 3.5',
DeprecationWarning, stacklevel=2)
return "0" <= char <= "9"
def isname(name):
import warnings
warnings.warn('sre_parse.isname() will be removed in 3.5',
DeprecationWarning, stacklevel=2)
# check that group name is a valid string
if not isident(name[0]):
return False
for char in name[1:]:
if not isident(char) and not isdigit(char):
return False
return True
def _class_escape(source, escape):
# handle escape code inside character class
code = ESCAPES.get(escape)
@ -351,9 +324,7 @@ def _class_escape(source, escape):
raise ValueError
if len(escape) == 2:
if c in ASCIILETTERS:
import warnings
warnings.warn('bad escape %s' % escape,
DeprecationWarning, stacklevel=8)
raise source.error('bad escape %s' % escape, len(escape))
return LITERAL, ord(escape[1])
except ValueError:
pass
@ -418,9 +389,7 @@ def _escape(source, escape, state):
raise source.error("invalid group reference", len(escape))
if len(escape) == 2:
if c in ASCIILETTERS:
import warnings
warnings.warn('bad escape %s' % escape,
DeprecationWarning, stacklevel=8)
raise source.error("bad escape %s" % escape, len(escape))
return LITERAL, ord(escape[1])
except ValueError:
pass
@ -798,10 +767,7 @@ def fix_flags(src, flags):
# Check and fix flags according to the type of pattern (str or bytes)
if isinstance(src, str):
if flags & SRE_FLAG_LOCALE:
import warnings
warnings.warn("LOCALE flag with a str pattern is deprecated. "
"Will be an error in 3.6",
DeprecationWarning, stacklevel=6)
raise ValueError("cannot use LOCALE flag with a str pattern")
if not flags & SRE_FLAG_ASCII:
flags |= SRE_FLAG_UNICODE
elif flags & SRE_FLAG_UNICODE:
@ -810,10 +776,7 @@ def fix_flags(src, flags):
if flags & SRE_FLAG_UNICODE:
raise ValueError("cannot use UNICODE flag with a bytes pattern")
if flags & SRE_FLAG_LOCALE and flags & SRE_FLAG_ASCII:
import warnings
warnings.warn("ASCII and LOCALE flags are incompatible. "
"Will be an error in 3.6",
DeprecationWarning, stacklevel=6)
raise ValueError("ASCII and LOCALE flags are incompatible")
return flags
def parse(str, flags=0, pattern=None):
@ -914,9 +877,7 @@ def parse_template(source, pattern):
this = chr(ESCAPES[this][1])
except KeyError:
if c in ASCIILETTERS:
import warnings
warnings.warn('bad escape %s' % this,
DeprecationWarning, stacklevel=4)
raise s.error('bad escape %s' % this, len(this))
lappend(this)
else:
lappend(this)

View File

@ -124,7 +124,7 @@ class ReTests(unittest.TestCase):
(chr(9)+chr(10)+chr(11)+chr(13)+chr(12)+chr(7)+chr(8)))
for c in 'cdehijklmopqsuwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ':
with self.subTest(c):
with self.assertWarns(DeprecationWarning):
with self.assertRaises(re.error):
self.assertEqual(re.sub('a', '\\' + c, 'a'), '\\' + c)
self.assertEqual(re.sub('^\s*', 'X', 'test'), 'Xtest')
@ -633,14 +633,10 @@ class ReTests(unittest.TestCase):
re.purge() # for warnings
for c in 'ceghijklmopqyzCEFGHIJKLMNOPQRTVXY':
with self.subTest(c):
with self.assertWarns(DeprecationWarning):
self.assertEqual(re.fullmatch('\\%c' % c, c).group(), c)
self.assertIsNone(re.match('\\%c' % c, 'a'))
self.assertRaises(re.error, re.compile, '\\%c' % c)
for c in 'ceghijklmopqyzABCEFGHIJKLMNOPQRTVXYZ':
with self.subTest(c):
with self.assertWarns(DeprecationWarning):
self.assertEqual(re.fullmatch('[\\%c]' % c, c).group(), c)
self.assertIsNone(re.match('[\\%c]' % c, 'a'))
self.assertRaises(re.error, re.compile, '[\\%c]' % c)
def test_string_boundaries(self):
# See http://bugs.python.org/issue10713
@ -993,10 +989,8 @@ class ReTests(unittest.TestCase):
self.assertTrue(re.match((r"\x%02x" % i).encode(), bytes([i])))
self.assertTrue(re.match((r"\x%02x0" % i).encode(), bytes([i])+b"0"))
self.assertTrue(re.match((r"\x%02xz" % i).encode(), bytes([i])+b"z"))
with self.assertWarns(DeprecationWarning):
self.assertTrue(re.match(br"\u1234", b'u1234'))
with self.assertWarns(DeprecationWarning):
self.assertTrue(re.match(br"\U00012345", b'U00012345'))
self.assertRaises(re.error, re.compile, br"\u1234")
self.assertRaises(re.error, re.compile, br"\U00012345")
self.assertTrue(re.match(br"\0", b"\000"))
self.assertTrue(re.match(br"\08", b"\0008"))
self.assertTrue(re.match(br"\01", b"\001"))
@ -1018,10 +1012,8 @@ class ReTests(unittest.TestCase):
self.assertTrue(re.match((r"[\x%02x]" % i).encode(), bytes([i])))
self.assertTrue(re.match((r"[\x%02x0]" % i).encode(), bytes([i])))
self.assertTrue(re.match((r"[\x%02xz]" % i).encode(), bytes([i])))
with self.assertWarns(DeprecationWarning):
self.assertTrue(re.match(br"[\u1234]", b'u'))
with self.assertWarns(DeprecationWarning):
self.assertTrue(re.match(br"[\U00012345]", b'U'))
self.assertRaises(re.error, re.compile, br"[\u1234]")
self.assertRaises(re.error, re.compile, br"[\U00012345]")
self.checkPatternError(br"[\567]",
r'octal escape value \567 outside of '
r'range 0-0o377', 1)
@ -1363,12 +1355,12 @@ class ReTests(unittest.TestCase):
if bletter:
self.assertIsNone(pat.match(bletter))
# Incompatibilities
self.assertWarns(DeprecationWarning, re.compile, '', re.LOCALE)
self.assertWarns(DeprecationWarning, re.compile, '(?L)')
self.assertWarns(DeprecationWarning, re.compile, b'', re.LOCALE | re.ASCII)
self.assertWarns(DeprecationWarning, re.compile, b'(?L)', re.ASCII)
self.assertWarns(DeprecationWarning, re.compile, b'(?a)', re.LOCALE)
self.assertWarns(DeprecationWarning, re.compile, b'(?aL)')
self.assertRaises(ValueError, re.compile, '', re.LOCALE)
self.assertRaises(ValueError, re.compile, '(?L)')
self.assertRaises(ValueError, re.compile, b'', re.LOCALE | re.ASCII)
self.assertRaises(ValueError, re.compile, b'(?L)', re.ASCII)
self.assertRaises(ValueError, re.compile, b'(?a)', re.LOCALE)
self.assertRaises(ValueError, re.compile, b'(?aL)')
def test_bug_6509(self):
# Replacement strings of both types must parse properly.
@ -1419,13 +1411,6 @@ class ReTests(unittest.TestCase):
# Test behaviour when not given a string or pattern as parameter
self.assertRaises(TypeError, re.compile, 0)
def test_bug_13899(self):
# Issue #13899: re pattern r"[\A]" should work like "A" but matches
# nothing. Ditto B and Z.
with self.assertWarns(DeprecationWarning):
self.assertEqual(re.findall(r'[\A\B\b\C\Z]', 'AB\bCZ'),
['A', 'B', '\b', 'C', 'Z'])
@bigmemtest(size=_2G, memuse=1)
def test_large_search(self, size):
# Issue #10182: indices were 32-bit-truncated.

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@ -38,6 +38,9 @@ Core and Builtins
Library
-------
- Issue #27030: Unknown escapes consisting of ``'\'`` and ASCII letter in
regular expressions now are errors.
- Issue #27186: Add os.PathLike support to DirEntry (part of PEP 519).
Initial patch by Jelle Zijlstra.