PayWithAmazon\ClientTest::test500or503 PHP Method

    public function test500or503()
    {
        try {
            $client = new Client($this->configParams);
            $url = 'https://www.justcharge.me/OffAmazonPayments_Sandbox/2013-01-01';
            $client->setMwsServiceUrl($url);
            $this->callPrivateMethod($client, 'invokePost', null);
        } catch (\Exception $expected) {
            $this->assertRegExp('/Maximum number of retry attempts./i', strval($expected));
        }
    }