From a8b6e327671237f516023ba5bd0b75bd998d6cbe Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Wed, 21 May 2014 11:38:42 +0200
Subject: [PATCH] Gracefully handle loading config files having empty strings
 for multi-value options (like wipe). #2003

---
 lib/Slic3r/GUI/OptionsGroup.pm | 4 +++-
 xs/t/15_config.t               | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/Slic3r/GUI/OptionsGroup.pm b/lib/Slic3r/GUI/OptionsGroup.pm
index f6e63fab8..69c60114b 100644
--- a/lib/Slic3r/GUI/OptionsGroup.pm
+++ b/lib/Slic3r/GUI/OptionsGroup.pm
@@ -231,7 +231,9 @@ sub _build_field {
             });
         } else {
             $field = Wx::TextCtrl->new($self->parent, -1, $opt->{default}, wxDefaultPosition, $size, $style);
-            $self->_setters->{$opt_key} = sub { $field->ChangeValue($_[0]) };
+            # value supplied to the setter callback might be undef in case user loads a config
+            # that has empty string for multi-value options like 'wipe'
+            $self->_setters->{$opt_key} = sub { $field->ChangeValue($_[0]) if defined $_[0] };
             EVT_TEXT($self->parent, $field, $on_change);
             EVT_KILL_FOCUS($field, $on_kill_focus);
         }
diff --git a/xs/t/15_config.t b/xs/t/15_config.t
index 57603ed1a..282670080 100644
--- a/xs/t/15_config.t
+++ b/xs/t/15_config.t
@@ -4,7 +4,7 @@ use strict;
 use warnings;
 
 use Slic3r::XS;
-use Test::More tests => 112;
+use Test::More tests => 114;
 
 foreach my $config (Slic3r::Config->new, Slic3r::Config::Full->new) {
     $config->set('layer_height', 0.3);
@@ -101,6 +101,8 @@ foreach my $config (Slic3r::Config->new, Slic3r::Config::Full->new) {
     is $config->serialize('wipe'), '1,0', 'serialize bools';
     $config->set_deserialize('wipe', '0,1,1');
     is_deeply $config->get('wipe'), [0,1,1], 'deserialize bools';
+    $config->set_deserialize('wipe', '');
+    is_deeply $config->get('wipe'), [], 'deserialize bools from empty string';
     $config->set_deserialize('retract_layer_change', 0);
     is_deeply $config->get('retract_layer_change'), [0], 'deserialize bools from non-string value';
     {