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):
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)
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
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
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against rawhide during the development of a Fedora release that is no
longer maintained.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flagging all of the open bugs for releases which are no longer
maintained.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:
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.