diff --git a/Doc/library/fnmatch.rst b/Doc/library/fnmatch.rst index 49073c5a292..0352b5233da 100644 --- a/Doc/library/fnmatch.rst +++ b/Doc/library/fnmatch.rst @@ -84,13 +84,6 @@ patterns. <_sre.SRE_Match object at 0x...> -.. function:: purge() - - Clear the internal pattern cache. - - .. versionadded:: 3.2 - - .. seealso:: Module :mod:`glob` diff --git a/Lib/fnmatch.py b/Lib/fnmatch.py index 7c20e74abee..726fbe556e8 100644 --- a/Lib/fnmatch.py +++ b/Lib/fnmatch.py @@ -12,19 +12,9 @@ corresponding to PATTERN. (It does not compile it.) import os import posixpath import re +import functools -__all__ = ["filter", "fnmatch", "fnmatchcase", "purge", "translate"] - -_cache = {} # Maps text patterns to compiled regexen. -_cacheb = {} # Ditto for bytes patterns. -_MAXCACHE = 100 # Maximum size of caches. - - -def purge(): - """Clear the pattern cache.""" - _cache.clear() - _cacheb.clear() - +__all__ = ["filter", "fnmatch", "fnmatchcase", "translate"] def fnmatch(name, pat): """Test whether FILENAME matches PATTERN. @@ -45,28 +35,21 @@ def fnmatch(name, pat): pat = os.path.normcase(pat) return fnmatchcase(name, pat) - -def _compile_pattern(pat): - cache = _cacheb if isinstance(pat, bytes) else _cache - regex = cache.get(pat) - if regex is None: - if isinstance(pat, bytes): - pat_str = str(pat, 'ISO-8859-1') - res_str = translate(pat_str) - res = bytes(res_str, 'ISO-8859-1') - else: - res = translate(pat) - if len(cache) >= _MAXCACHE: - cache.clear() - cache[pat] = regex = re.compile(res) - return regex.match - +@functools.lru_cache(maxsize=250) +def _compile_pattern(pat, is_bytes=False): + if is_bytes: + pat_str = str(pat, 'ISO-8859-1') + res_str = translate(pat_str) + res = bytes(res_str, 'ISO-8859-1') + else: + res = translate(pat) + return re.compile(res).match def filter(names, pat): """Return the subset of the list NAMES that match PAT.""" result = [] pat = os.path.normcase(pat) - match = _compile_pattern(pat) + match = _compile_pattern(pat, isinstance(pat, bytes)) if os.path is posixpath: # normcase on posix is NOP. Optimize it away from the loop. for name in names: @@ -78,14 +61,13 @@ def filter(names, pat): result.append(name) return result - def fnmatchcase(name, pat): """Test whether FILENAME matches PATTERN, including case. This is a version of fnmatch() which doesn't case-normalize its arguments. """ - match = _compile_pattern(pat) + match = _compile_pattern(pat, isinstance(pat, bytes)) return match(name) is not None diff --git a/Lib/test/test_fnmatch.py b/Lib/test/test_fnmatch.py index a93558c7dd3..482835d42ef 100644 --- a/Lib/test/test_fnmatch.py +++ b/Lib/test/test_fnmatch.py @@ -3,15 +3,10 @@ from test import support import unittest -from fnmatch import (fnmatch, fnmatchcase, _MAXCACHE, _cache, _cacheb, purge, - translate, filter) - +from fnmatch import fnmatch, fnmatchcase, translate, filter class FnmatchTestCase(unittest.TestCase): - def tearDown(self): - purge() - def check_match(self, filename, pattern, should_match=1, fn=fnmatch): if should_match: self.assertTrue(fn(filename, pattern), @@ -65,22 +60,6 @@ class FnmatchTestCase(unittest.TestCase): self.check_match(b'test\xff', b'te*\xff') self.check_match(b'foo\nbar', b'foo*') - def test_cache_clearing(self): - # check that caches do not grow too large - # http://bugs.python.org/issue7846 - - # string pattern cache - for i in range(_MAXCACHE + 1): - fnmatch('foo', '?' * i) - - self.assertLessEqual(len(_cache), _MAXCACHE) - - # bytes pattern cache - for i in range(_MAXCACHE + 1): - fnmatch(b'foo', b'?' * i) - self.assertLessEqual(len(_cacheb), _MAXCACHE) - - class TranslateTestCase(unittest.TestCase): def test_translate(self):