The trait SimpleSAML\XML\TestUtils\SchemaValidationTestTrait requires some properties which are not provided by SimpleSAML\XMLSecurity\Test\XML\ds\KeyNameTest: $documentElement, $ownerDocument, $message, $line
The trait SimpleSAML\XML\TestUtils...lizableElementTestTrait requires the property $documentElement which is not provided by SimpleSAML\XMLSecurity\Test\XML\ds\KeyNameTest.