SAML2\AssertionTest::testAttributeValuesWithComplexTypesAreParsedCorrectly PHP Method

    public function testAttributeValuesWithComplexTypesAreParsedCorrectly()
    {
        $xml = <<<XML
            <saml:Assertion
                    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
                    xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol"
                    xmlns:xs="http://www.w3.org/2001/XMLSchema"
                    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                    Version="2.0"
                    ID="_93af655219464fb403b34436cfb0c5cb1d9a5502"
                    IssueInstant="1970-01-01T01:33:31Z">
            <saml:Issuer>Provider</saml:Issuer>
            <saml:Conditions/>
            <saml:AttributeStatement>
              <saml:Attribute Name="urn:some:custom:outer:element" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri">
                <saml:AttributeValue>
                  <saml:Attribute Name="urn:some:custom:nested:element">
                    <saml:AttributeValue>abcd-some-value-xyz</saml:AttributeValue>
                  </saml:Attribute>
                </saml:AttributeValue>
              </saml:Attribute>
              <saml:Attribute Name="urn:EntityConcernedSubID" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri">
                <saml:AttributeValue xsi:type="xs:string">string</saml:AttributeValue>
              </saml:Attribute>
            </saml:AttributeStatement>
            </saml:Assertion>
XML;
        $assertion = new Assertion(DOMDocumentFactory::fromString($xml)->firstChild);
        $attributes = $assertion->getAttributes();
        $this->assertInstanceOf('\\DOMNodeList', $attributes['urn:some:custom:outer:element'][0]);
        $this->assertXmlStringEqualsXmlString($xml, $assertion->toXML()->ownerDocument->saveXML());
    }