Re: gitk does not show path file list

Mark Blakeney [off-list ref] writes:

... why does gitk (usually) not show the subset list of files affected
when you give it a path?

E.g. If I am in a src dir then "gitk ." does not list files. Neither does "gitk
$PWD" nor "gitk ../src". However "cd ..; git src" does list files!?

Paul, I do not read Tcl very well, but it appears that path_filter
procedure is at fault.

The call chain involved in this seems to be:

    gettreediffs
     - arranges gettreediffline to be fed output from "diff-tree $commit ."

 ->

    gettreediffline
     - finds the path (note that diff output is _always_ relative to the
       top of the work tree) from the patch;
     - calls path_filter with $vfilelimit($curview) and each filename
       In this case, the $vfilelimit($curview) is "." (dot)

 ->

    path_filter
     - compares strings in $filter and the $name; in this case, $filter is
       a dot "." and $name begins with "src/"

I see at least two problems in path_filter used this way:

 - A dot "." never would match anything from "diff-tree" (or any "diff"
   variant) after stripping a/ and b/ prefix.  gitk should prefix the
   current directory to each of the pathspec from command line (run
   "rev-parse --show-prefix" to learn where you are).

 - There is another callsite to path_filter for filtering output from
   "ls-files -u".  But the output from "ls-files" is relative to the cwd
   by default.  gitk should probably run it with --full-name option, so
   that it would get the same semantics as "diff" output.

It _might_ be the easiest to do an equivalent of (sorry, I do not talk Tcl
so this is in shell):

	prefix=$(git rev-parse --show-prefix)
	if test -n "$prefix"
        then
        	cd $(git rev-parse --show-cdup)
	fi

and then prepend prefix to all the pathspecs you would use from the
command line before doing anything else.  This "prepending" obviously need
to be aware of the ".", ".." and friends.