public function testCharge() { $client = new Client($this->configParams); $apiCallParams = array('amazon_reference_id' => 'S01-TEST'); try { $client = new Client($this->configParams); $apiCallParams = array('amazon_reference_id' => ''); $client->charge($apiCallParams); } catch (\Exception $expected) { $this->assertRegExp('/key amazon_order_reference_id or amazon_billing_agreement_id is null and is a required parameter./i', strval($expected)); } try { $client = new Client($this->configParams); $apiCallParams = array('amazon_reference_id' => 'T01'); $client->charge($apiCallParams); } catch (\Exception $expected) { $this->assertRegExp('/Invalid Amazon Reference ID./i', strval($expected)); } }