Exception with EXTMATCH on pattern like '!(not)_@(this|that)'

[jakedane]

• OS: Arch Linux
• python version: 3.12.3
• wcmatch version: 8.5.1

When using a pattern like !(not)_@(this|that) and EXTMATCH an exception missing ), unterminated subpattern at position 5 is raised. The issue happens when a !(pattern-list) is followed by a @(pattern-list).

As a trivialized example say I have the files 1_foo, 2_foo and 3_bar and I want to match all files except the 2nd, I could use a pattern !(2)_@(foo|bar). Matching the 1st file like this:

from wcmatch import fnmatch
fnmatch.fnmatch('1_foo', '!(2)_@(foo|bar)', flags = fnmatch.EXTMATCH)

Should result True but instead the fnmatch call raises this exception:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3.12/site-packages/wcmatch/fnmatch.py", line 86, in fnmatch
    return bool(_wcparse.compile(patterns, flags, limit, exclude=exclude).match(filename))
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/wcmatch/_wcparse.py", line 787, in compile
    positive, negative = compile_pattern(patterns, flags, limit, exclude)
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/wcmatch/_wcparse.py", line 739, in compile_pattern
    positive.append(_compile(expanded, flags))
                    ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/wcmatch/_wcparse.py", line 798, in _compile
    return re.compile(WcParse(pattern, flags & FLAG_MASK).parse())
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/__init__.py", line 228, in compile
    return _compile(pattern, flags)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/__init__.py", line 307, in _compile
    p = _compiler.compile(pattern, flags)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/_compiler.py", line 745, in compile
    p = _parser.parse(p, flags)
        ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/_parser.py", line 979, in parse
    p = _parse_sub(source, state, flags & SRE_FLAG_VERBOSE, 0)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/_parser.py", line 862, in _parse
    p = _parse_sub(source, state, sub_verbose, nested + 1)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/re/_parser.py", line 864, in _parse
    raise source.error("missing ), unterminated subpattern",
re.error: missing ), unterminated subpattern at position 5

In bash it works:

$ touch 1_foo 2_foo 3_bar
$ ls !(2)_@(foo|bar)
1_foo  3_bar

[facelessuser]

Yeah, the negate case in EXTMATCH was always a little tricky to get right. I have a fix for this though in PR #219.

>>> fnmatch.fnmatch('1_foo', '!(2)_@(foo|bar)', flags = fnmatch.EXTMATCH)
True

[facelessuser]

I've tagged a new release. It should be available shortly on PyPI.

[jakedane]

Nice, thank you!