Neos\Flow\Mvc\Controller\Argument::setDefaultValue PHP Method

    public function setDefaultValue($defaultValue)
    {
        $this->defaultValue = $defaultValue;
        return $this;
    }

 /**
  * @test
  */
 public function setDefaultValueShouldProvideFluentInterfaceAndReallySetDefaultValue()
 {
     $returnedArgument = $this->simpleValueArgument->setDefaultValue('default');
     $this->assertSame($this->simpleValueArgument, $returnedArgument, 'The returned argument is not the original argument.');
     $this->assertSame('default', $this->simpleValueArgument->getDefaultValue());
 }