Braintree\Gateway::merchant PHP Method

    public function merchant()
    {
        return new MerchantGateway($this);
    }

 public function testBadPaymentMethods()
 {
     $gateway = new Braintree\Gateway(array('clientId' => 'client_id$development$integration_client_id', 'clientSecret' => 'client_secret$development$integration_client_secret'));
     $result = $gateway->merchant()->create(array('email' => '*****@*****.**', 'countryCodeAlpha3' => 'USA', 'paymentMethods' => ['fake_money']));
     $this->assertEquals(false, $result->success);
     $errors = $result->errors->forKey('merchant')->onAttribute('paymentMethods');
     $this->assertEquals(Braintree\Error\Codes::MERCHANT_ACCOUNT_PAYMENT_METHODS_ARE_INVALID, $errors[0]->code);
 }