cpython/Doc/library/filecmp.rst
Benjamin Peterson e0124bd9c3 Merged revisions 69998-69999,70002,70022-70023,70025-70026,70061,70086,70145,70171,70183,70188,70235,70244,70275,70281 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r69998 | benjamin.peterson | 2009-02-26 13:04:40 -0600 (Thu, 26 Feb 2009) | 1 line

  the startship is rather outdated now
........
  r69999 | benjamin.peterson | 2009-02-26 13:05:59 -0600 (Thu, 26 Feb 2009) | 1 line

  comma
........
  r70002 | andrew.kuchling | 2009-02-26 16:34:30 -0600 (Thu, 26 Feb 2009) | 1 line

  The curses panel library is now supported
........
  r70022 | georg.brandl | 2009-02-27 10:23:18 -0600 (Fri, 27 Feb 2009) | 1 line

  #5361: fix typo.
........
  r70023 | georg.brandl | 2009-02-27 10:39:26 -0600 (Fri, 27 Feb 2009) | 1 line

  #5363: fix cmpfiles() docs. Another instance where a prose description is twice as long as the code.
........
  r70025 | georg.brandl | 2009-02-27 10:52:55 -0600 (Fri, 27 Feb 2009) | 1 line

  #5344: fix punctuation.
........
  r70026 | georg.brandl | 2009-02-27 10:59:03 -0600 (Fri, 27 Feb 2009) | 1 line

  #5365: add quick look conversion table for different time representations.
........
  r70061 | hirokazu.yamamoto | 2009-02-28 09:24:00 -0600 (Sat, 28 Feb 2009) | 1 line

  Binary flag is needed on windows.
........
  r70086 | benjamin.peterson | 2009-03-01 21:35:12 -0600 (Sun, 01 Mar 2009) | 1 line

  fix a silly problem of caching gone wrong #5401
........
  r70145 | benjamin.peterson | 2009-03-03 16:51:57 -0600 (Tue, 03 Mar 2009) | 1 line

  making the writing more formal
........
  r70171 | facundo.batista | 2009-03-04 15:18:17 -0600 (Wed, 04 Mar 2009) | 3 lines

  Fixed a typo.
........
  r70183 | benjamin.peterson | 2009-03-04 18:17:57 -0600 (Wed, 04 Mar 2009) | 1 line

  add example
........
  r70188 | hirokazu.yamamoto | 2009-03-05 03:34:14 -0600 (Thu, 05 Mar 2009) | 1 line

  Fixed memory leak on failure.
........
  r70235 | benjamin.peterson | 2009-03-07 18:21:17 -0600 (Sat, 07 Mar 2009) | 1 line

  fix funky indentation
........
  r70244 | martin.v.loewis | 2009-03-08 09:06:19 -0500 (Sun, 08 Mar 2009) | 2 lines

  Add Chris Withers.
........
  r70275 | georg.brandl | 2009-03-09 11:35:48 -0500 (Mon, 09 Mar 2009) | 2 lines

  Add missing space.
........
  r70281 | benjamin.peterson | 2009-03-09 15:38:56 -0500 (Mon, 09 Mar 2009) | 1 line

  gzip and bz2 are context managers
........
2009-03-09 21:04:33 +00:00

163 lines
4.3 KiB
ReStructuredText

:mod:`filecmp` --- File and Directory Comparisons
=================================================
.. module:: filecmp
:synopsis: Compare files efficiently.
.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
The :mod:`filecmp` module defines functions to compare files and directories,
with various optional time/correctness trade-offs. For comparing files,
see also the :mod:`difflib` module.
The :mod:`filecmp` module defines the following functions:
.. function:: cmp(f1, f2[, shallow])
Compare the files named *f1* and *f2*, returning ``True`` if they seem equal,
``False`` otherwise.
Unless *shallow* is given and is false, files with identical :func:`os.stat`
signatures are taken to be equal.
Files that were compared using this function will not be compared again unless
their :func:`os.stat` signature changes.
Note that no external programs are called from this function, giving it
portability and efficiency.
.. function:: cmpfiles(dir1, dir2, common[, shallow])
Compare the files in the two directories *dir1* and *dir2* whose names are
given by *common*.
Returns three lists of file names: *match*, *mismatch*,
*errors*. *match* contains the list of files that match, *mismatch* contains
the names of those that don't, and *errors* lists the names of files which
could not be compared. Files are listed in *errors* if they don't exist in
one of the directories, the user lacks permission to read them or if the
comparison could not be done for some other reason.
The *shallow* parameter has the same meaning and default value as for
:func:`filecmp.cmp`.
For example, ``cmpfiles('a', 'b', ['c', 'd/e'])`` will compare ``a/c`` with
``b/c`` and ``a/d/e`` with ``b/d/e``. ``'c'`` and ``'d/e'`` will each be in
one of the three returned lists.
Example::
>>> import filecmp
>>> filecmp.cmp('undoc.rst', 'undoc.rst')
True
>>> filecmp.cmp('undoc.rst', 'index.rst')
False
.. _dircmp-objects:
The :class:`dircmp` class
-------------------------
:class:`dircmp` instances are built using this constructor:
.. class:: dircmp(a, b[, ignore[, hide]])
Construct a new directory comparison object, to compare the directories *a* and
*b*. *ignore* is a list of names to ignore, and defaults to ``['RCS', 'CVS',
'tags']``. *hide* is a list of names to hide, and defaults to ``[os.curdir,
os.pardir]``.
The :class:`dircmp` class provides the following methods:
.. method:: report()
Print (to ``sys.stdout``) a comparison between *a* and *b*.
.. method:: report_partial_closure()
Print a comparison between *a* and *b* and common immediate
subdirectories.
.. method:: report_full_closure()
Print a comparison between *a* and *b* and common subdirectories
(recursively).
The :class:`dircmp` offers a number of interesting attributes that may be
used to get various bits of information about the directory trees being
compared.
Note that via :meth:`__getattr__` hooks, all attributes are computed lazily,
so there is no speed penalty if only those attributes which are lightweight
to compute are used.
.. attribute:: left_list
Files and subdirectories in *a*, filtered by *hide* and *ignore*.
.. attribute:: right_list
Files and subdirectories in *b*, filtered by *hide* and *ignore*.
.. attribute:: common
Files and subdirectories in both *a* and *b*.
.. attribute:: left_only
Files and subdirectories only in *a*.
.. attribute:: right_only
Files and subdirectories only in *b*.
.. attribute:: common_dirs
Subdirectories in both *a* and *b*.
.. attribute:: common_files
Files in both *a* and *b*
.. attribute:: common_funny
Names in both *a* and *b*, such that the type differs between the
directories, or names for which :func:`os.stat` reports an error.
.. attribute:: same_files
Files which are identical in both *a* and *b*.
.. attribute:: diff_files
Files which are in both *a* and *b*, whose contents differ.
.. attribute:: funny_files
Files which are in both *a* and *b*, but could not be compared.
.. attribute:: subdirs
A dictionary mapping names in :attr:`common_dirs` to :class:`dircmp` objects.