/**
  * @covers ::prepareCallback
  *
  * @dataProvider providerPrepareCallback
  *
  * @param string|callable $unprepared_callback
  * @param callable $prepared_callback
  */
 public function testPrepareCallback($unprepared_callback, callable $prepared_callback)
 {
     $this->decoratedFormState->prepareCallback($unprepared_callback)->willReturn($prepared_callback)->shouldBeCalled();
     $this->assertSame($prepared_callback, $this->formStateDecoratorBase->prepareCallback($unprepared_callback));
 }