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