izzum\statemachine\Context::getEntityId PHP Method

    public function getEntityId()
    {
        return $this->getIdentifier()->getEntityId();
    }

 /**
  * @test
  */
 public function shouldAcceptMultipleCallableTypes()
 {
     //there are diverse ways to use callables: closures, anonymous function, instance methods
     //static methods.
     //https://php.net/manual/en/functions.anonymous.php
     //https://php.net/manual/en/language.types.callable.php
     $context = new Context(new Identifier('123', 'foo-machine'));
     $event = 'foo';
     $a = new State('a');
     $b = new State('b');
     //scenario 1: Closure without variables from the parent scope
     $transition_callable = function ($entity) {
         $entity->setEntityId('234');
     };
     $t = new Transition($a, $b, $event, null, null, null, $transition_callable);
     $this->assertEquals('123', $context->getEntityId());
     $t->process($context);
     $this->assertEquals('234', $context->getEntityId());
     //scenario 2: Closure with Inheriting variables from the parent scope
     $x = 4;
     $transition_callable = function ($entity) use(&$x) {
         $x += 1;
     };
     $t = new Transition($a, $b, $event, null, null, null, $transition_callable);
     $this->assertEquals(4, $x);
     $t->process($context);
     $this->assertEquals(5, $x);
     //scenario 3: Anonymous function / literal
     $context->getIdentifier()->setEntityId('123');
     $t = new Transition($a, $b, $event, null, null, null, function ($entity) {
         $entity->setEntityId('234');
     });
     $this->assertEquals('123', $context->getEntityId());
     $t->process($context);
     $this->assertEquals('234', $context->getEntityId());
     //scenario 4: instance method invocation (method as string)
     $helper = new CallableHelper();
     $transition_callable = array($helper, 'increaseInstanceId');
     $t = new Transition($a, $b, $event, null, null, null, $transition_callable);
     $this->assertEquals(0, $helper->instance_id);
     $t->process($context);
     $this->assertEquals(1, $helper->instance_id);
     $t->process($context);
     $this->assertEquals(2, $helper->instance_id);
     //scenario 5: static method invocation in array (use fully qualified name)
     $helper = new CallableHelper();
     $transition_callable = array('izzum\\statemachine\\CallableHelper', 'increaseId');
     $t = new Transition($a, $b, $event, null, null, null, $transition_callable);
     $this->assertEquals(0, CallableHelper::$id);
     $t->process($context);
     $this->assertEquals(1, CallableHelper::$id);
     //scenario 6: static method invocation in string (use fully qualified name)
     //THIS IS THE WAY TO be able to specify a callable in a configuration file.
     $helper = new CallableHelper();
     $transition_callable = 'izzum\\statemachine\\CallableHelper::increaseId';
     $t = new Transition($a, $b, $event, null, null, null, $transition_callable);
     $this->assertEquals(1, CallableHelper::$id);
     $t->process($context);
     $this->assertEquals(2, CallableHelper::$id);
     //scenario 7: wrap an existing method in a closure (this is THE way to reuse an existing method)
     function jo($entity)
     {
         $entity->setEntityId($entity->getEntityId() + 1);
     }
     $callable = function ($context) {
         jo($context);
     };
     $context->getIdentifier()->setEntityId('123');
     $t = new Transition($a, $b, $event, null, null, null, $callable);
     $this->assertEquals('123', $context->getEntityId());
     $t->process($context);
     $this->assertEquals('124', $context->getEntityId());
 }