Storage role splitted into storage and storage_class

Signed-off-by: Pedro Melo <melo@simplicidade.org>

lib/Config/Connie/Storage.pm

@@ -1,10 +1,19 @@
 package Config::Connie::Storage;
 
 use Moo::Role;
+use Carp ();
 use namespace::autoclean;
 
-requires 'build_storage';
+has 'storage' => (is => 'lazy', builder => 'build_storage', handles => ['check_for_updates']);
+has 'storage_class' => (is => 'lazy', builder => 'build_storage_class');
+
+sub build_storage {
+  my ($self) = @_;
+
+  return $self->storage_class->new(instance => $self);
+}
+
+sub build_storage_class { Carp::confess "Class '" . ref(shift) . "' requires a build_storage_class method" }
 
-has 'storage' => (is => 'ro', builder => 'build_storage', handles => ['check_for_updates']);
 
 1;

t/tlib/T/Storage/Config.pm

@@ -14,6 +14,6 @@ with
 
 sub default_config_id {'defaults_id'}
 
-sub build_storage { Config::Connie::Storage::Local->new(instance => shift) }
+sub build_storage_class {'Config::Connie::Storage::Local'}
 
 1;