diff --git a/t/custom_gcode.t b/t/custom_gcode.t
index ea36c0cf1..69ab8fac8 100644
--- a/t/custom_gcode.t
+++ b/t/custom_gcode.t
@@ -1,4 +1,4 @@
-use Test::More tests => 1;
+use Test::More tests => 2;
 use strict;
 use warnings;
 
@@ -10,32 +10,43 @@ BEGIN {
 use Slic3r;
 use Slic3r::Test;
 
-my $config = Slic3r::Config->new_from_defaults;
-
-my $test = sub {
-    my ($conf) = @_;
-    $conf ||= $config;
+{
+    my $config = Slic3r::Config->new_from_defaults;
     
-    my $print = Slic3r::Test::init_print('2x20x10', config => $conf);
-    
-    my $last_move_was_z_change = 0;
-    Slic3r::Test::GCodeReader->new(gcode => Slic3r::Test::gcode($print))->parse(sub {
-        my ($self, $cmd, $args, $info) = @_;
+    my $test = sub {
+        my ($conf) = @_;
+        $conf ||= $config;
         
-        if ($last_move_was_z_change && $cmd ne $config->layer_gcode) {
-            fail 'custom layer G-code was not applied after Z change';
-        }
-        if (!$last_move_was_z_change && $cmd eq $config->layer_gcode) {
-            fail 'custom layer G-code was not applied after Z change';
-        }
+        my $print = Slic3r::Test::init_print('2x20x10', config => $conf);
         
-        $last_move_was_z_change = (defined $info->{dist_Z} && $info->{dist_Z} > 0);
-    });
+        my $last_move_was_z_change = 0;
+        Slic3r::Test::GCodeReader->new(gcode => Slic3r::Test::gcode($print))->parse(sub {
+            my ($self, $cmd, $args, $info) = @_;
+            
+            if ($last_move_was_z_change && $cmd ne $config->layer_gcode) {
+                fail 'custom layer G-code was not applied after Z change';
+            }
+            if (!$last_move_was_z_change && $cmd eq $config->layer_gcode) {
+                fail 'custom layer G-code was not applied after Z change';
+            }
+            
+            $last_move_was_z_change = (defined $info->{dist_Z} && $info->{dist_Z} > 0);
+        });
+        
+        1;
+    };
     
-    1;
-};
+    $config->set('layer_gcode', '_MY_CUSTOM_GCODE_');
+    ok $test->(), "custom layer G-code is applied after Z move and before other moves";
+}
 
-$config->set('layer_gcode', '_MY_CUSTOM_GCODE_');
-ok $test->(), "custom layer G-code is applied after Z move and before other moves";
+#==========================================================
+
+{
+    my $config = Slic3r::Config->new_from_defaults;
+    is $config->replace_options('[temperature_[foo]]', { foo => '0' }),
+        200,
+        "nested config options";
+}
 
 __END__