git-gui: fix exception when trying to stage with empty file list

If there is nothing to stage, there is nothing to stage. Let's not try
to, even if the file list contains nothing at all.

This fixes https://github.com/git-for-windows/git/issues/1075

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-gui.sh b/git-gui.sh
index 3ce2e04bc58ee2c0f17cf86b4d72bab7549b3f78..b3c14acbdf740b2073954bdc8ef49496db228b65 100755 (executable)
--- a/git-gui.sh
+++ b/git-gui.sh
@@ -2505,7 +2505,9 @@ proc toggle_or_diff {mode w args} {
                if {$last_clicked ne {}} {
                        set lno [lindex $last_clicked 1]
                } else {
-                       if {[llength $file_lists($w)] == 0} {
+                       if {![info exists file_lists]
+                               || ![info exists file_lists($w)]
+                               || [llength $file_lists($w)] == 0} {
                                set last_clicked {}
                                return
                        }
@@ -2519,7 +2521,13 @@ proc toggle_or_diff {mode w args} {
                }
        }
 
-       set path [lindex $file_lists($w) [expr {$lno - 1}]]
+       if {![info exists file_lists]
+               || ![info exists file_lists($w)]
+               || [llength $file_lists($w)] < $lno - 1} {
+               set path {}
+       } else {
+               set path [lindex $file_lists($w) [expr {$lno - 1}]]
+       }
        if {$path eq {}} {
                set last_clicked {}
                return