[issue11747] unified_diff function product incorrect range information
Roundup Robot devnull@devnull added the comment: New changeset 707078ca0a77 by Raymond Hettinger in branch '3.1': Issue 11747: Fix output format for context diffs. http://hg.python.org/cpython/rev/707078ca0a77 New changeset e3387295a24f by Raymond Hettinger in branch '3.2': Issue 11747: Fix output format for context diffs. http://hg.python.org/cpython/rev/e3387295a24f New changeset fbfd5435889c by Raymond Hettinger in branch 'default': Issue 11747: Fix output format for context diffs. http://hg.python.org/cpython/rev/fbfd5435889c -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Roundup Robot devnull@devnull added the comment: New changeset 09459397f807 by Raymond Hettinger in branch '2.7': Issue 11747: Fix output format for context diffs. http://hg.python.org/cpython/rev/09459397f807 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Changes by Raymond Hettinger raymond.hettin...@gmail.com: -- resolution: - fixed status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Roundup Robot devnull@devnull added the comment: New changeset a2ee967de44f by Raymond Hettinger in branch '3.2': Issue #11747: Fix range formatting in context and unified diffs. http://hg.python.org/cpython/rev/a2ee967de44f New changeset 1e5e3bb3e1f1 by Raymond Hettinger in branch 'default': Issue #11747: Fix range formatting in context and unified diffs. http://hg.python.org/cpython/rev/1e5e3bb3e1f1 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Changes by Raymond Hettinger raymond.hettin...@gmail.com: -- resolution: - fixed status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Raymond Hettinger raymond.hettin...@gmail.com added the comment: Re-opening. There are some problems with the fix. Context diff ranges need to show the ending line number, not the length. Also for unified diffs, GNU diff is showing (x,0) as just (x). -- priority: low - high resolution: fixed - status: closed - open ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Roundup Robot devnull@devnull added the comment: New changeset 36648097fcd4 by Raymond Hettinger in branch '3.2': Cleanup and modernize code prior to working on Issue 11747. http://hg.python.org/cpython/rev/36648097fcd4 New changeset 58a3bfcc70f7 by Raymond Hettinger in branch 'default': Cleanup and modernize code prior to working on Issue 11747. http://hg.python.org/cpython/rev/58a3bfcc70f7 -- nosy: +python-dev ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Raymond Hettinger raymond.hettin...@gmail.com added the comment: [Uncle Timmy] Would have to look at the history to see who added it, and ask them. That would be me :-) At the time, the goals were to: 1) make an easy-to-use, readable output format for file comparisons, 2) use the unmodified output of the existing SequenceMatcher(None,a,b).get_grouped_opcodes(n) method, 3) create output that works with patch and ed, and 4) comply with the output format spec in the Single Unix Specification found at http://www.unix.org/single_unix_specification/ . See the attached excerpt. No effort was made to exactly reproduce the output of GNU diff. It was just an alternate output format for the SequenceMatcher. -- nosy: +rhettinger Added file: http://bugs.python.org/file21594/Diff_Format.pdf ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Changes by Raymond Hettinger raymond.hettin...@gmail.com: -- assignee: - rhettinger priority: normal - low ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Terry J. Reedy tjre...@udel.edu added the comment: Thanks, Raymond. That file says (in the -u section) If a range is empty, its beginning line number shall be the number of the line just before the range, or 0 if the empty range starts the file. The last clause says to me that gnu diff is right and that the 1,0 range of difflib.unified_diff is a bug. I think we should add this link to the difflib doc (I am still thinking about place and wording). News entry might be Issue # 11747: Correct difflib.unified_diff empty file range from 1,0 to 0,0 in conformance with Single Unix Specification for diff output formats. Patch by ysj.ray. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Terry J. Reedy tjre...@udel.edu added the comment: @Tim: was it your intention that difflib track gnu diff? I am on the fence with this issue. Without input from Tim other than the doc, I am tempted to call this a feature request and retitle it Make unified_diff match gnu diff for [] input. The docs do not reference external definitions for context-diff and unified-diff. The entry for unified-diff does not give a format for the @@ control lines. So the current behavior cannot be said to violate the doc spec. On the other hand, putting random garbage on @@ lines would clearly be a bug, so the doc must be taken as referencing some external definition, even if vague. https://secure.wikimedia.org/wikipedia/en/wiki/Diff#Unified_format says Unified context diffs were originally developed by Wayne Davison in August 1990 (in unidiff which appeared in Volume 14 of comp.sources.misc). Richard Stallman added unified diff support to the GNU Project's diff utility one month later,. So using gnu diff as a standard is not unreasonable. (But did it give 0,0 for null files from the beginning?) Now looking practically. If nothing but patch programs ever read and act on the control blocks, then, say Ray, a change would neither hurt nor be of any use. If any Python code does look, then a change could break code. I would in any case be reluntant to change 2.7. But if this is treated as a feature request and only 3.3 swere changed, then we would have to document the change: Version changed 3.3: for empty lists, the @@ block specification was changed from 1,0 to 0,0, which is pretty close to adding useless noise. 3.0 would have been the best time to make this change. -- nosy: +terry.reedy, tim_one stage: - patch review ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
Tim Peters tim.pet...@gmail.com added the comment: Terry, I had no intention here at all - had nothing to do with unified_diff. Would have to look at the history to see who added it, and ask them. That said, the very name unified_diff suggests someone did intend to mimic _some_ system's unified diff behavior ;-) -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
ysj.ray ysj@gmail.com added the comment: Since if one of the two comparing files is empty, gnu diff regards the beginning line of differences as line 0 (there is not any lines), but difflib regards it as line 1(there is a line, but empty). Not sure weather is correct since the practice usage of diff output is feeding it to patch program which determine the different line location mostly based on context identical lines instead of the line numbers in the hunk headers, so it doesn't matter weather it's line 0 or line 1. But it is still better to keep consist with gnu diff. In context_diff() it is correct since if there is less then 2 different lines in a hunk, only ending line number is display in hunk header. Here is a patch which fix this. -- keywords: +patch nosy: +ysj.ray type: - behavior versions: +Python 3.1, Python 3.2, Python 3.3 Added file: http://bugs.python.org/file21539/issue_11747.diff ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
New submission from Jan Koprowski jan.koprow...@gmail.com: Python: --- import difflib dl = difflib.unified_diff([], ['a\n', 'b\n']) print ''.join(dl), --- +++ @@ -1,0 +1,2 @@ +a +b Gnu diff: --- $diff -uN a b --- a 1970-01-01 01:00:00.0 +0100 +++ b 2011-04-03 06:56:28.330543000 +0200 @@ -0,0 +1,2 @@ +a +b -- components: Library (Lib) messages: 132832 nosy: jan.koprowski priority: normal severity: normal status: open title: unified_diff function product incorrect range information versions: Python 2.7 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
