destroy() public method

Delete the session data from Cloud Datastore.
public destroy ( $id )
 /**
  * @expectedException PHPUnit_Framework_Error_Warning
  */
 public function testDestroyWithException()
 {
     $key = new Key('projectid');
     $key->pathElement(self::KIND, 'sessionid');
     $this->transaction->delete($key)->shouldBeCalledTimes(1);
     $this->transaction->commit()->shouldBeCalledTimes(1)->willThrow(new Exception());
     $this->datastore->transaction()->shouldBeCalledTimes(1)->willReturn($this->transaction->reveal());
     $this->datastore->key(self::KIND, 'sessionid', ['namespaceId' => self::NAMESPACE_ID])->shouldBeCalledTimes(1)->willReturn($key);
     $datastoreSessionHandler = new DatastoreSessionHandler($this->datastore->reveal());
     $datastoreSessionHandler->open(self::NAMESPACE_ID, self::KIND);
     $ret = $datastoreSessionHandler->destroy('sessionid');
     $this->assertEquals(false, $ret);
 }