SAML2\Certificate\FingerprintLoader::loadFingerprints PHP Method

    public function loadFingerprints(CertificateProvider $configuration)
    {
        $fingerprints = $configuration->getCertificateFingerprints();
        if (!is_array($fingerprints) && !$fingerprints instanceof \Traversable) {
            throw InvalidArgumentException::invalidType('array or instanceof \\Traversable', $fingerprints);
        }
        $collection = new FingerprintCollection();
        foreach ($fingerprints as $fingerprint) {
            if (!is_string($fingerprint) && !(is_object($fingerprint) && method_exists($fingerprint, '__toString'))) {
                throw InvalidArgumentException::invalidType('fingerprint as string or object that can be casted to string', $fingerprint);
            }
            $collection->add(new Fingerprint((string) $fingerprint));
        }
        return $collection;
    }

 /**
  * @group        certificate
  * @test
  *
  * @dataProvider invalidConfigurationProvider
  * @expectedException \SAML2\Exception\InvalidArgumentException
  */
 public function it_correctly_parses_arrays_and_traversables($configurationValue)
 {
     $this->configurationMock->shouldReceive('getCertificateFingerprints')->once()->andReturn($configurationValue);
     $result = $this->fingerprintLoader->loadFingerprints($this->configurationMock);
     $this->assertInstanceOf('\\SAML2\\Certificate\\FingerprintCollection', $result);
     $this->assertCount(count($configurationValue), $result);
 }