gitk: Fix "blame parent commit" with separate work tree

Running "blame parent commit" currently brings up an empty blame view
when the the work tree is not the parent of the git directory.  Fix it
by feeding git-blame paths relative to $GIT_WORK_TREE instead of
"$GIT_DIR/..".

Signed-off-by: Martin von Zweigbergk <martin.von.zweigbergk@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/gitk b/gitk
index 4c99dd601a326e2a2cf595348ffd5fb6182de425..862646779fbc59cdad41f904ee5bd11ef1adfcf2 100755 (executable)
--- a/gitk
+++ b/gitk
@@ -3557,7 +3557,7 @@ proc make_relative {f} {
 }
 
 proc external_blame {parent_idx {line {}}} {
-    global flist_menu_file gitdir
+    global flist_menu_file cdup
     global nullid nullid2
     global parentlist selectedline currentid
 
@@ -3576,7 +3576,7 @@ proc external_blame {parent_idx {line {}}} {
     if {$line ne {} && $line > 1} {
        lappend cmdline "--line=$line"
     }
-    set f [file join [file dirname $gitdir] $flist_menu_file]
+    set f [file join $cdup $flist_menu_file]
     # Unfortunately it seems git gui blame doesn't like
     # being given an absolute path...
     set f [make_relative $f]