PayWithAmazon\ClientTest::callPrivateMethod PHP Method

    private function callPrivateMethod($client, $methodName, $parameters)
    {
        $reflectionClass = new \ReflectionClass("PayWithAmazon\\Client");
        $reflectionMethod = $reflectionClass->getMethod($methodName);
        $reflectionMethod->setAccessible(true);
        $expectedStringParams = $reflectionMethod->invoke($client, $parameters);
        return $expectedStringParams;
    }