Wrong exception from re.compile()

[warsaw]

BPO	545855
Nosy	@warsaw, @brettcannon

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = <Date 2003-05-17.01:53:02.000>
created_at = <Date 2002-04-18.22:22:48.000>
labels = ['expert-regex']
title = 'Wrong exception from re.compile()'
updated_at = <Date 2003-05-17.01:53:02.000>
user = 'https://github.com/warsaw'

bugs.python.org fields:

activity = <Date 2003-05-17.01:53:02.000>
actor = 'brett.cannon'
assignee = 'effbot'
closed = True
closed_date = None
closer = None
components = ['Regular Expressions']
creation = <Date 2002-04-18.22:22:48.000>
creator = 'barry'
dependencies = []
files = []
hgrepos = []
issue_num = 545855
keywords = []
message_count = 3.0
messages = ['10413', '10414', '10415']
nosy_count = 4.0
nosy_names = ['effbot', 'barry', 'brett.cannon', 'mbrierst']
pr_nums = []
priority = 'normal'
resolution = 'out of date'
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue545855'
versions = ['Python 2.2']

[warsaw]

re.compile('foo[a-') raises a TypeError exception
instead of re.error.

Python 2.2.1 (#1, Apr  4 2002, 17:22:15) 
[GCC 2.96 20000731 (Mandrake Linux 8.2 2.96-0.76mdk)]
on linux2
Type "help", "copyright", "credits" or "license" for
more information.
>>> import re
>>> re.compile('foo[a-')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/local/lib/python2.2/sre.py", line 178, in
compile
    return _compile(pattern, flags)
  File "/usr/local/lib/python2.2/sre.py", line 226, in
_compile
    p = sre_compile.compile(pattern, flags)
  File "/usr/local/lib/python2.2/sre_compile.py", line
430, in compile
    p = sre_parse.parse(p, flags)
  File "/usr/local/lib/python2.2/sre_parse.py", line
623, in parse
    p = _parse_sub(source, pattern, 0)
  File "/usr/local/lib/python2.2/sre_parse.py", line
318, in _parse_sub
    items.append(_parse(source, state))
  File "/usr/local/lib/python2.2/sre_parse.py", line
424, in _parse
    if this[0] == "\\":
TypeError: unsubscriptable object

[mbrierst]

Logged In: YES
user_id=670441

Patch below fixes the problem. Didn't check for end of expression in one case.

Index: dist/src/Lib/sre_parse.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/sre_parse.py,v
retrieving revision 1.55
diff -c -r1.55 sre_parse.py
*** dist/src/Lib/sre_parse.py 2 Jun 2002 00:40:05 -0000 1.55
--- dist/src/Lib/sre_parse.py 4 Feb 2003 19:53:14 -0000

---

*** 420,429 ****
set.append((LITERAL, ord("-")))
break
else:
! if this[0] == "\\":
code2 = _class_escape(source, this)
! else:
code2 = LITERAL, ord(this)
if code1[0] != LITERAL or code2[0] != LITERAL:
raise error, "bad character range"
lo = code1[1]
--- 420,431 ----

                          set.append((LITERAL, ord("-")))
                          break
                      else:
!                         if this and this[0] == "\\":
                              code2 = _class_escape(source, this)
!                         elif this:
                              code2 = LITERAL, ord(this)
+                         else:
+                             raise error, "unexpected end of regular expression"
                          if code1[0] != LITERAL or code2[0] != LITERAL:
                              raise error, "bad character range"
                          lo = code1[1]

[brettcannon]

Logged In: YES
user_id=357491

This is fixed in 2.2.2 and 2.3b1. Closing as out of date.