mirror of
https://github.com/python/cpython.git
synced 2024-11-21 21:09:37 +01:00
321 lines
10 KiB
Python
321 lines
10 KiB
Python
"""Utilities for comparing files and directories.
|
|
|
|
Classes:
|
|
dircmp
|
|
|
|
Functions:
|
|
cmp(f1, f2, shallow=True) -> int
|
|
cmpfiles(a, b, common) -> ([], [], [])
|
|
clear_cache()
|
|
|
|
"""
|
|
|
|
import os
|
|
import stat
|
|
from itertools import filterfalse
|
|
from types import GenericAlias
|
|
|
|
__all__ = ['clear_cache', 'cmp', 'dircmp', 'cmpfiles', 'DEFAULT_IGNORES']
|
|
|
|
_cache = {}
|
|
BUFSIZE = 8*1024
|
|
|
|
DEFAULT_IGNORES = [
|
|
'RCS', 'CVS', 'tags', '.git', '.hg', '.bzr', '_darcs', '__pycache__']
|
|
|
|
def clear_cache():
|
|
"""Clear the filecmp cache."""
|
|
_cache.clear()
|
|
|
|
def cmp(f1, f2, shallow=True):
|
|
"""Compare two files.
|
|
|
|
Arguments:
|
|
|
|
f1 -- First file name
|
|
|
|
f2 -- Second file name
|
|
|
|
shallow -- treat files as identical if their stat signatures (type, size,
|
|
mtime) are identical. Otherwise, files are considered different
|
|
if their sizes or contents differ. [default: True]
|
|
|
|
Return value:
|
|
|
|
True if the files are the same, False otherwise.
|
|
|
|
This function uses a cache for past comparisons and the results,
|
|
with cache entries invalidated if their stat information
|
|
changes. The cache may be cleared by calling clear_cache().
|
|
|
|
"""
|
|
|
|
s1 = _sig(os.stat(f1))
|
|
s2 = _sig(os.stat(f2))
|
|
if s1[0] != stat.S_IFREG or s2[0] != stat.S_IFREG:
|
|
return False
|
|
if shallow and s1 == s2:
|
|
return True
|
|
if s1[1] != s2[1]:
|
|
return False
|
|
|
|
outcome = _cache.get((f1, f2, s1, s2))
|
|
if outcome is None:
|
|
outcome = _do_cmp(f1, f2)
|
|
if len(_cache) > 100: # limit the maximum size of the cache
|
|
clear_cache()
|
|
_cache[f1, f2, s1, s2] = outcome
|
|
return outcome
|
|
|
|
def _sig(st):
|
|
return (stat.S_IFMT(st.st_mode),
|
|
st.st_size,
|
|
st.st_mtime)
|
|
|
|
def _do_cmp(f1, f2):
|
|
bufsize = BUFSIZE
|
|
with open(f1, 'rb') as fp1, open(f2, 'rb') as fp2:
|
|
while True:
|
|
b1 = fp1.read(bufsize)
|
|
b2 = fp2.read(bufsize)
|
|
if b1 != b2:
|
|
return False
|
|
if not b1:
|
|
return True
|
|
|
|
# Directory comparison class.
|
|
#
|
|
class dircmp:
|
|
"""A class that manages the comparison of 2 directories.
|
|
|
|
dircmp(a, b, ignore=None, hide=None, *, shallow=True)
|
|
A and B are directories.
|
|
IGNORE is a list of names to ignore,
|
|
defaults to DEFAULT_IGNORES.
|
|
HIDE is a list of names to hide,
|
|
defaults to [os.curdir, os.pardir].
|
|
SHALLOW specifies whether to just check the stat signature (do not read
|
|
the files).
|
|
defaults to True.
|
|
|
|
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 instances (or MyDirCmp instances if this
|
|
object is of type MyDirCmp, a subclass of dircmp), keyed by names
|
|
in common_dirs.
|
|
"""
|
|
|
|
def __init__(self, a, b, ignore=None, hide=None, *, shallow=True): # 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 = DEFAULT_IGNORES
|
|
else:
|
|
self.ignore = ignore
|
|
self.shallow = shallow
|
|
|
|
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()
|
|
|
|
def phase1(self): # Compute common names
|
|
a = dict(zip(map(os.path.normcase, self.left_list), self.left_list))
|
|
b = dict(zip(map(os.path.normcase, self.right_list), self.right_list))
|
|
self.common = list(map(a.__getitem__, filter(b.__contains__, a)))
|
|
self.left_only = list(map(a.__getitem__, filterfalse(b.__contains__, a)))
|
|
self.right_only = list(map(b.__getitem__, filterfalse(a.__contains__, b)))
|
|
|
|
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 = True
|
|
try:
|
|
a_stat = os.stat(a_path)
|
|
except (OSError, ValueError):
|
|
# See https://github.com/python/cpython/issues/122400
|
|
# for the rationale for protecting against ValueError.
|
|
# print('Can\'t stat', a_path, ':', why.args[1])
|
|
ok = False
|
|
try:
|
|
b_stat = os.stat(b_path)
|
|
except (OSError, ValueError):
|
|
# print('Can\'t stat', b_path, ':', why.args[1])
|
|
ok = False
|
|
|
|
if ok:
|
|
a_type = stat.S_IFMT(a_stat.st_mode)
|
|
b_type = stat.S_IFMT(b_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.shallow)
|
|
self.same_files, self.diff_files, self.funny_files = xx
|
|
|
|
def phase4(self): # Find out differences between common subdirectories
|
|
# A new dircmp (or MyDirCmp if dircmp was subclassed) 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] = self.__class__(a_x, b_x, self.ignore, self.hide,
|
|
shallow=self.shallow)
|
|
|
|
def phase4_closure(self): # Recursively call phase4() on subdirectories
|
|
self.phase4()
|
|
for sd in self.subdirs.values():
|
|
sd.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 sd in self.subdirs.values():
|
|
print()
|
|
sd.report()
|
|
|
|
def report_full_closure(self): # Report on self and subdirs recursively
|
|
self.report()
|
|
for sd in self.subdirs.values():
|
|
print()
|
|
sd.report_full_closure()
|
|
|
|
methodmap = dict(subdirs=phase4,
|
|
same_files=phase3, diff_files=phase3, funny_files=phase3,
|
|
common_dirs=phase2, common_files=phase2, common_funny=phase2,
|
|
common=phase1, left_only=phase1, right_only=phase1,
|
|
left_list=phase0, right_list=phase0)
|
|
|
|
def __getattr__(self, attr):
|
|
if attr not in self.methodmap:
|
|
raise AttributeError(attr)
|
|
self.methodmap[attr](self)
|
|
return getattr(self, attr)
|
|
|
|
__class_getitem__ = classmethod(GenericAlias)
|
|
|
|
|
|
def cmpfiles(a, b, common, shallow=True):
|
|
"""Compare common files in two directories.
|
|
|
|
a, b -- directory names
|
|
common -- list of file names found in both directories
|
|
shallow -- if true, do comparison based solely on stat() information
|
|
|
|
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:
|
|
ax = os.path.join(a, x)
|
|
bx = os.path.join(b, x)
|
|
res[_cmp(ax, bx, shallow)].append(x)
|
|
return res
|
|
|
|
|
|
# Compare two files.
|
|
# Return:
|
|
# 0 for equal
|
|
# 1 for different
|
|
# 2 for funny cases (can't stat, NUL bytes, etc.)
|
|
#
|
|
def _cmp(a, b, sh, abs=abs, cmp=cmp):
|
|
try:
|
|
return not abs(cmp(a, b, sh))
|
|
except (OSError, ValueError):
|
|
return 2
|
|
|
|
|
|
# Return a copy with items that occur in skip removed.
|
|
#
|
|
def _filter(flist, skip):
|
|
return list(filterfalse(skip.__contains__, flist))
|
|
|
|
|
|
# Demonstration and testing.
|
|
#
|
|
def demo():
|
|
import sys
|
|
import getopt
|
|
options, args = getopt.getopt(sys.argv[1:], 'r')
|
|
if len(args) != 2:
|
|
raise getopt.GetoptError('need exactly two args', None)
|
|
dd = dircmp(args[0], args[1])
|
|
if ('-r', '') in options:
|
|
dd.report_full_closure()
|
|
else:
|
|
dd.report()
|
|
|
|
if __name__ == '__main__':
|
|
demo()
|