Lib/fnmatch.py

   1 """Filename matching with shell patterns.
   2
   3 fnmatch(FILENAME, PATTERN) matches according to the local convention.
   4 fnmatchcase(FILENAME, PATTERN) always takes case in account.
   5
   6 The functions operate by translating the pattern into a regular
   7 expression.  They cache the compiled regular expressions for speed.
   8
   9 The function translate(PATTERN) returns a regular expression
  10 corresponding to PATTERN.  (It does not compile it.)
  11 """
  12
  13 import re
  14
  15 __all__ = ["fnmatch","fnmatchcase","translate"]
  16
  17 _cache = {}
  18
  19 def fnmatch(name, pat):
  20     """Test whether FILENAME matches PATTERN.
  21
  22     Patterns are Unix shell style:
  23
  24     *       matches everything
  25     ?       matches any single character
  26     [seq]   matches any character in seq
  27     [!seq]  matches any char not in seq
  28
  29     An initial period in FILENAME is not special.
  30     Both FILENAME and PATTERN are first case-normalized
  31     if the operating system requires it.
  32     If you don't want this, use fnmatchcase(FILENAME, PATTERN).
  33     """
  34
  35     import os
  36     name = os.path.normcase(name)
  37     pat = os.path.normcase(pat)
  38     return fnmatchcase(name, pat)
  39
  40 def fnmatchcase(name, pat):
  41     """Test whether FILENAME matches PATTERN, including case.
  42
  43     This is a version of fnmatch() which doesn't case-normalize
  44     its arguments.
  45     """
  46
  47     if not _cache.has_key(pat):
  48         res = translate(pat)
  49         _cache[pat] = re.compile(res)
  50     return _cache[pat].match(name) is not None
  51
  52 def translate(pat):
  53     """Translate a shell PATTERN to a regular expression.
  54
  55     There is no way to quote meta-characters.
  56     """
  57
  58     i, n = 0, len(pat)
  59     res = ''
  60     while i < n:
  61         c = pat[i]
  62         i = i+1
  63         if c == '*':
  64             res = res + '.*'
  65         elif c == '?':
  66             res = res + '.'
  67         elif c == '[':
  68             j = i
  69             if j < n and pat[j] == '!':
  70                 j = j+1
  71             if j < n and pat[j] == ']':
  72                 j = j+1
  73             while j < n and pat[j] != ']':
  74                 j = j+1
  75             if j >= n:
  76                 res = res + '\\['
  77             else:
  78                 stuff = pat[i:j]
  79                 i = j+1
  80                 if stuff[0] == '!':
  81                     stuff = '[^' + stuff[1:] + ']'
  82                 elif stuff == '^'*len(stuff):
  83                     stuff = '\\^'
  84                 else:
  85                     while stuff[0] == '^':
  86                         stuff = stuff[1:] + stuff[0]
  87                     stuff = '[' + stuff + ']'
  88                 res = res + stuff
  89         else:
  90             res = res + re.escape(c)
  91     return res + "$"