Whoops! We just discovered that Gordon's revamp of this module was
accidentally wiped out by Ping's patch (which shouldn't have affected
this file at all, had Ping done a cvs update).
This checkin restores Gordon's version, with Fredrik's change merged
back in.
diff --git a/Lib/filecmp.py b/Lib/filecmp.py
index 24ae4b3..072293e 100644
--- a/Lib/filecmp.py
+++ b/Lib/filecmp.py
@@ -1,68 +1,329 @@
-"""Compare files."""
+"""Utilities for comparing files and directories.
-import os, stat, statcache
+Classes:
+ dircmp
+
+Functions:
+ cmp(f1, f2, shallow=1, use_statcache=0) -> int
+ cmpfiles(a, b, common) -> ([], [], [])
+
+"""
+
+import os
+import stat
+import statcache
_cache = {}
BUFSIZE=8*1024
-def cmp(f1, f2, shallow=1,use_statcache=0):
- """Compare two files.
+def cmp(f1, f2, shallow=1,use_statcache=0):
+ """Compare two files.
- Arguments:
+ Arguments:
- f1 -- First file name
+ f1 -- First file name
- f2 -- Second file name
+ f2 -- Second file name
- shallow -- Just check stat signature (do not read the files).
- defaults to 1.
+ shallow -- Just check stat signature (do not read the files).
+ defaults to 1.
- use_statcache -- Do not stat() each file directly: go through
- the statcache module for more efficiency.
+ use_statcache -- Do not stat() each file directly: go through
+ the statcache module for more efficiency.
- Return value:
+ Return value:
- integer -- 1 if the files are the same, 0 otherwise.
+ integer -- 1 if the files are the same, 0 otherwise.
- This function uses a cache for past comparisons and the results,
- with a cache invalidation mechanism relying on stale signatures.
- Of course, if 'use_statcache' is true, this mechanism is defeated,
- and the cache will never grow stale.
+ This function uses a cache for past comparisons and the results,
+ with a cache invalidation mechanism relying on stale signatures.
+ Of course, if 'use_statcache' is true, this mechanism is defeated,
+ and the cache will never grow stale.
- """
- if use_statcache:
- stat_function = statcache.stat
- else:
- stat_function = os.stat
- s1 = _sig(stat_function(f1))
- s2 = _sig(stat_function(f2))
- if s1[0] != stat.S_IFREG or s2[0] != stat.S_IFREG:
- return 0
- if shallow and s1 == s2:
- return 1
- if s1[1] != s2[1]:
- return 0
+ """
+ if use_statcache:
+ stat_function = statcache.stat
+ else:
+ stat_function = os.stat
+ s1 = _sig(stat_function(f1))
+ s2 = _sig(stat_function(f2))
+ if s1[0] != stat.S_IFREG or s2[0] != stat.S_IFREG:
+ return 0
+ if shallow and s1 == s2:
+ return 1
+ if s1[1] != s2[1]:
+ return 0
- result = _cache.get((f1, f2))
- if result and (s1, s2) == result[:2]:
- return result[2]
- outcome = _do_cmp(f1, f2)
- _cache[f1, f2] = s1, s2, outcome
- return outcome
+ result = _cache.get((f1, f2))
+ if result and (s1, s2) == result[:2]:
+ return result[2]
+ outcome = _do_cmp(f1, f2)
+ _cache[f1, f2] = s1, s2, outcome
+ return outcome
def _sig(st):
- return (stat.S_IFMT(st[stat.ST_MODE]),
- st[stat.ST_SIZE],
- st[stat.ST_MTIME])
+ return (stat.S_IFMT(st[stat.ST_MODE]),
+ st[stat.ST_SIZE],
+ st[stat.ST_MTIME])
def _do_cmp(f1, f2):
- bufsize = BUFSIZE
- fp1 = open(f1, 'rb')
- fp2 = open(f2, 'rb')
- while 1:
- b1 = fp1.read(bufsize)
- b2 = fp2.read(bufsize)
- if b1 != b2:
- return 0
- if not b1:
- return 1
+ bufsize = BUFSIZE
+ fp1 = open(f1, 'rb')
+ fp2 = open(f2, 'rb')
+ while 1:
+ b1 = fp1.read(bufsize)
+ b2 = fp2.read(bufsize)
+ if b1 != b2:
+ return 0
+ if not b1:
+ return 1
+
+# Directory comparison class.
+#
+class dircmp:
+ """A class that manages the comparison of 2 directories.
+
+ dircmp(a,b,ignore=None,hide=None)
+ A and B are directories.
+ IGNORE is a list of names to ignore,
+ defaults to ['RCS', 'CVS', 'tags'].
+ HIDE is a list of names to hide,
+ defaults to [os.curdir, os.pardir].
+
+ High level usage:
+ x = dircmp(dir1, dir2)
+ x.report() -> prints a report on the differences between dir1 and dir2
+ or
+ x.report_partial_closure() -> prints report on differences between dir1
+ and dir2, and reports on common immediate subdirectories.
+ x.report_full_closure() -> like report_partial_closure,
+ but fully recursive.
+
+ Attributes:
+ left_list, right_list: The files in dir1 and dir2,
+ filtered by hide and ignore.
+ common: a list of names in both dir1 and dir2.
+ left_only, right_only: names only in dir1, dir2.
+ common_dirs: subdirectories in both dir1 and dir2.
+ common_files: files in both dir1 and dir2.
+ common_funny: names in both dir1 and dir2 where the type differs between
+ dir1 and dir2, or the name is not stat-able.
+ same_files: list of identical files.
+ diff_files: list of filenames which differ.
+ funny_files: list of files which could not be compared.
+ subdirs: a dictionary of dircmp objects, keyed by names in common_dirs.
+ """
+
+ def __init__(self, a, b, ignore=None, hide=None): # Initialize
+ self.left = a
+ self.right = b
+ if hide is None:
+ self.hide = [os.curdir, os.pardir] # Names never to be shown
+ else:
+ self.hide = hide
+ if ignore is None:
+ self.ignore = ['RCS', 'CVS', 'tags'] # Names ignored in comparison
+ else:
+ self.ignore = ignore
+
+ def phase0(self): # Compare everything except common subdirectories
+ self.left_list = _filter(os.listdir(self.left),
+ self.hide+self.ignore)
+ self.right_list = _filter(os.listdir(self.right),
+ self.hide+self.ignore)
+ self.left_list.sort()
+ self.right_list.sort()
+
+ __p4_attrs = ('subdirs',)
+ __p3_attrs = ('same_files', 'diff_files', 'funny_files')
+ __p2_attrs = ('common_dirs', 'common_files', 'common_funny')
+ __p1_attrs = ('common', 'left_only', 'right_only')
+ __p0_attrs = ('left_list', 'right_list')
+
+ def __getattr__(self, attr):
+ if attr in self.__p4_attrs:
+ self.phase4()
+ elif attr in self.__p3_attrs:
+ self.phase3()
+ elif attr in self.__p2_attrs:
+ self.phase2()
+ elif attr in self.__p1_attrs:
+ self.phase1()
+ elif attr in self.__p0_attrs:
+ self.phase0()
+ else:
+ raise AttributeError, attr
+ return getattr(self, attr)
+
+ def phase1(self): # Compute common names
+ a_only, b_only = [], []
+ common = {}
+ b = {}
+ for fnm in self.right_list:
+ b[fnm] = 1
+ for x in self.left_list:
+ if b.get(x, 0):
+ common[x] = 1
+ else:
+ a_only.append(x)
+ for x in self.right_list:
+ if common.get(x, 0):
+ pass
+ else:
+ b_only.append(x)
+ self.common = common.keys()
+ self.left_only = a_only
+ self.right_only = b_only
+
+ def phase2(self): # Distinguish files, directories, funnies
+ self.common_dirs = []
+ self.common_files = []
+ self.common_funny = []
+
+ for x in self.common:
+ a_path = os.path.join(self.left, x)
+ b_path = os.path.join(self.right, x)
+
+ ok = 1
+ try:
+ a_stat = statcache.stat(a_path)
+ except os.error, why:
+ # print 'Can\'t stat', a_path, ':', why[1]
+ ok = 0
+ try:
+ b_stat = statcache.stat(b_path)
+ except os.error, why:
+ # print 'Can\'t stat', b_path, ':', why[1]
+ ok = 0
+
+ if ok:
+ a_type = stat.S_IFMT(a_stat[stat.ST_MODE])
+ b_type = stat.S_IFMT(b_stat[stat.ST_MODE])
+ if a_type <> b_type:
+ self.common_funny.append(x)
+ elif stat.S_ISDIR(a_type):
+ self.common_dirs.append(x)
+ elif stat.S_ISREG(a_type):
+ self.common_files.append(x)
+ else:
+ self.common_funny.append(x)
+ else:
+ self.common_funny.append(x)
+
+ def phase3(self): # Find out differences between common files
+ xx = cmpfiles(self.left, self.right, self.common_files)
+ self.same_files, self.diff_files, self.funny_files = xx
+
+ def phase4(self): # Find out differences between common subdirectories
+ # A new dircmp object is created for each common subdirectory,
+ # these are stored in a dictionary indexed by filename.
+ # The hide and ignore properties are inherited from the parent
+ self.subdirs = {}
+ for x in self.common_dirs:
+ a_x = os.path.join(self.left, x)
+ b_x = os.path.join(self.right, x)
+ self.subdirs[x] = dircmp(a_x, b_x, self.ignore, self.hide)
+
+ def phase4_closure(self): # Recursively call phase4() on subdirectories
+ self.phase4()
+ for x in self.subdirs.keys():
+ self.subdirs[x].phase4_closure()
+
+ def report(self): # Print a report on the differences between a and b
+ # Output format is purposely lousy
+ print 'diff', self.left, self.right
+ if self.left_only:
+ self.left_only.sort()
+ print 'Only in', self.left, ':', self.left_only
+ if self.right_only:
+ self.right_only.sort()
+ print 'Only in', self.right, ':', self.right_only
+ if self.same_files:
+ self.same_files.sort()
+ print 'Identical files :', self.same_files
+ if self.diff_files:
+ self.diff_files.sort()
+ print 'Differing files :', self.diff_files
+ if self.funny_files:
+ self.funny_files.sort()
+ print 'Trouble with common files :', self.funny_files
+ if self.common_dirs:
+ self.common_dirs.sort()
+ print 'Common subdirectories :', self.common_dirs
+ if self.common_funny:
+ self.common_funny.sort()
+ print 'Common funny cases :', self.common_funny
+
+ def report_partial_closure(self): # Print reports on self and on subdirs
+ self.report()
+ for x in self.subdirs.keys():
+ print
+ self.subdirs[x].report()
+
+ def report_full_closure(self): # Report on self and subdirs recursively
+ self.report()
+ for x in self.subdirs.keys():
+ print
+ self.subdirs[x].report_full_closure()
+
+
+# Compare common files in two directories.
+# Return:
+# - files that compare equal
+# - files that compare different
+# - funny cases (can't stat etc.)
+#
+def cmpfiles(a, b, common):
+ """Compare common files in two directories.
+
+ cmpfiles(a,b,common)
+ A and B are directory names
+ COMMON is a list of file names
+ returns a tuple of three lists:
+ files that compare equal
+ files that are different
+ filenames that aren't regular files."""
+
+ res = ([], [], [])
+ for x in common:
+ res[_cmp(os.path.join(a, x), os.path.join(b, x))].append(x)
+ return res
+
+
+# Compare two files.
+# Return:
+# 0 for equal
+# 1 for different
+# 2 for funny cases (can't stat, etc.)
+#
+def _cmp(a, b):
+ try:
+ return not abs(cmp(a, b))
+ except os.error:
+ return 2
+
+
+# Return a copy with items that occur in skip removed.
+#
+def _filter(list, skip):
+ result = []
+ for item in list:
+ if item not in skip: result.append(item)
+ return result
+
+
+# Demonstration and testing.
+#
+def demo():
+ import sys
+ import getopt
+ options, args = getopt.getopt(sys.argv[1:], 'r')
+ if len(args) <> 2: raise getopt.error, 'need exactly two args'
+ dd = dircmp(args[0], args[1])
+ if ('-r', '') in options:
+ dd.report_full_closure()
+ else:
+ dd.report()
+
+if __name__ == '__main__':
+ demo()