Error : Unit Test your Forms

[GCalmels]

I followed the doc with Sf2.8 for adding custom extensions and I have an error when I run phpunit

Here my previous issue : symfony/symfony#20952

[GCalmels]

I post the solution I found :

protected function getExtensions()
    {
        $this->validator = $this->createMock(ValidatorInterface::class);
        $this->validator
            ->method('validate')
            ->will($this->returnValue(new ConstraintViolationList()));
        $this->validator
            ->method('getMetadataFor')
            ->will($this->returnValue(new ClassMetadata('Symfony\Component\Form\Form')));

        return array(
            new ValidatorExtension($this->validator)
        );
    }