Merge commit 'upstream/topic/configfile_default_codref_call'

* commit 'upstream/topic/configfile_default_codref_call':
  if configfile is a coderef call it and write some tests for it

diff --combined lib/MooseX/Getopt.pm
index 90a9d77,d0dbb3f..08bf037
--- 1/lib/MooseX/Getopt.pm
--- 2/lib/MooseX/Getopt.pm
+++ b/lib/MooseX/Getopt.pm
@@@ -11,7 -11,7 +11,7 @@@ use Carp ()
  use Getopt::Long (); # GLD uses it anyway, doesn't hurt
  use constant HAVE_GLD => not not eval { require Getopt::Long::Descriptive };
  
 -our $VERSION   = '0.21';
 +our $VERSION   = '0.22';
  our $AUTHORITY = 'cpan:STEVAN';
  
  has ARGV       => (is => 'rw', isa => 'ArrayRef', metaclass => "NoGetopt");
@@@ -31,6 -31,11 +31,11 @@@ sub new_with_options 
          if(!defined $configfile) {
              my $cfmeta = $class->meta->find_attribute_by_name('configfile');
              $configfile = $cfmeta->default if $cfmeta->has_default;
+             if (ref $configfile eq 'CODE') {
+                 # not sure theres a lot you can do with the class and may break some assumptions
+                 # warn?
+                 $configfile = &$configfile($class);
+             }
              if (defined $configfile) {
                  $config_from_file = eval {
                      $class->get_config_from_file($configfile);