<?php namespace GraphQL\Tests; use GraphQL\Utils; class UtilsTest extends \PHPUnit_Framework_TestCase { public function testAssignThrowsExceptionOnMissingRequiredKey() { $object = new \stdClass(); $object->requiredKey = 'value'; try { Utils::assign($object, [], ['requiredKey']); $this->fail('Expected exception not thrown'); } catch (\InvalidArgumentException $e) { $this->assertEquals( "Key requiredKey is expected to be set and not to be null", $e->getMessage()); } } }