Red Hat Bugzilla – Bug 186027
filterdiff filename match is unpredictable
Last modified: 2008-06-16 04:31:17 EDT
Description of problem: When trying to build a script to filter certain parts out of a series of patches, the behaviour of filterdiff is unpredictable. Instead of simply picking the file name after +++ (new file name) as the key for -x and -i, filterdiff choses the shorter of the two file names. This makes it impossible to use eg. the output from diffstat for constructing an exclude list. To make things worse, this behaviour appears to be undocumented. Version-Release number of selected component (if applicable): patchutils-0.2.31-2.2.1 Expected results: The filenames that filterdiff works on should correspond to the ones shown in diffstat output. Yes, I know these are different packages, but they're used together all the time and having one of the tools exhibit such an unpredictable behaviour is a problem.
The algorithm that filterdiff/lsdiff uses is the one described in the patch(1) man page: To determine the best of a nonempty list of file names, patch first takes all the names with the fewest path name components; of those, it then takes all the names with the shortest basename; of those, it then takes all the shortest names; finally, it takes the first remaining name. However, I take your point that this can make -x and -i rather difficult to use in conjuction with other programs that use different rules. How are you invoking diffstat to get a parseable list of filenames to exclude/include? Really -x and -i were designed with lsdiff/grepdiff output in mind.
Based on the date this bug was created, it appears to have been reported against rawhide during the development of a Fedora release that is no longer maintained. In order to refocus our efforts as a project we are flagging all of the open bugs for releases which are no longer maintained. If this bug remains in NEEDINFO thirty (30) days from now, we will automatically close it. If you can reproduce this bug in a maintained Fedora version (7, 8, or rawhide), please change this bug to the respective version and change the status to ASSIGNED. (If you're unable to change the bug's version or status, add a comment to the bug and someone will change it for you.) Thanks for your help, and we apologize again that we haven't handled these issues to this point. The process we're following is outlined here: http://fedoraproject.org/wiki/BugZappers/F9CleanUp We will be following the process here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping to ensure this doesn't happen again.
There's been no code change, so this is still an issue.
Seems like '-p1' (for example) will do what you want in the majority of cases.