Patches item #1121142, was opened at 2005-02-11 19:08 Message generated for change (Comment added) made by alanmcintyre You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1121142&group_id=5470
Category: Library (Lib) Group: Python 2.5 Status: Open Resolution: None Priority: 5 Submitted By: Alan McIntyre (ESRG) (alanmcintyre) Assigned to: Nobody/Anonymous (nobody) Summary: ZipFile.open - read-only file-like obj for files in archive Initial Comment: I originally started working on updating patch 992750, but decided after a short while to just start from scratch, so I'm posting it as a new patch. Sorry if this isn't appropriate. This patch provides a new open() method on ZipFile; this method returns a file-like object for the requested item in the archive. This file-like object only provides a read() method. ZipFile.read was modified to use the new open method (this was suggested by loewis in reference to patch 992750). The patched zipfile.py passed the existing tests in the test_zipfile.py from CVS. New tests were added to verify the operation of the object returned by open(). These tests were modeled after existing tests for ZipFile.read(); two read fixed-size chunks from the file-like object, and two others read random-sized chunks. I have only run the tests on Windows XP, using Python2.4 from the official Windows installer. I will test the patch out on Linux over the weekend. If the patch is accepted I'll also generate and submit patches for the appropriate documentation as well. ---------------------------------------------------------------------- >Comment By: Alan McIntyre (ESRG) (alanmcintyre) Date: 2005-03-14 09:37 Message: Logged In: YES user_id=1115903 Hmm...I could have sworn I did the diff in the correct order. I'll make sure next time. :) Here's my comments on your remarks (in order): - I'm adding support for universal newlines, and will reject all modes that aren't legal combinations of r, U, and b. - I'll see if I can make a Zip file store something with compression < 1, and if I can I'll add a test case for it. - I'll try work a .flush() in there on the compression object and come up with a test case if possible - .read(0) and .readline(0) will both return an empty string with no side-effects, since this seems to be what builtin files do. Right now ZipExtFile uses the ZipFile's file object, so you pretty much have to do whatever you're going to do with the ZipExtFile instance you get back from .open() before you use that ZipFile instance in a way that moves the file pointer around. I'm sure that somebody will eventually try to use the ZipFile in this way, so it appears my options are either to (1) give the ZipExtFile its own file object to use (when possible), or (2) make sure this limitation is documented. #1 feels (to me) to be the "right thing" to do, so that's what I'll try unless there's a good reason I shouldn't. ---------------------------------------------------------------------- Comment By: Martin v. L�wis (loewis) Date: 2005-03-01 02:59 Message: Logged In: YES user_id=21627 The patch is reversed: usually, diff is invoked as "-c old new". I think it is almost right, but I have a few remarks: - by tradition, open() should have a mode argument, defaulting to 'r'; it would be ok to raise exceptions if it is anything else. However, do consider implementing universal newlines; allowing 'b' as a no-op might also be reasonable. - I wonder what happens if the compression rate is < 1. It would appear that the code might use too few rawbytes. I suggest to recursively invoke read in this case. - I wonder whether it could ever happen that there is still data to uncompress in the zlib object, ie. whether it might be necessary to invoke .flush() after exhausting the rawbytes (and discard the zlib object afterwards) - it appears that atleast the builtin file object implements .read(0) as returning an empty string; the manual says that the entire file is meant only if size is omitted or negative. ---------------------------------------------------------------------- Comment By: Alan McIntyre (ESRG) (alanmcintyre) Date: 2005-02-27 01:28 Message: Logged In: YES user_id=1115903 zipfile_patch2.tgz: I updated the file-like object to support readline, readlines, __iter__ and next(). Added tests for those new methods. Also added a patch for the documentation. Passes regression tests on 2.5a0 built from CVS HEAD with MSVC .NET on Windows XP. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1121142&group_id=5470 _______________________________________________ Patches mailing list [email protected] http://mail.python.org/mailman/listinfo/patches
