--- /dev/null
+package ORTestClass;
+
+use Moo;
+
+has counter => (is => 'rwp', default => sub { 0 });
+
+sub increment { $_[0]->_set_counter($_[0]->counter + 1); }
+
+sub pid { $$ }
+
+sub call_callback {
+ my ($self, $value, $cb) = @_;
+ $cb->();
+ return $value;
+}
+
+1;