/**
  * @return string The API URL for this Stripe refund.
  */
 public function instanceUrl()
 {
     $id = $this['id'];
     $fee = $this['fee'];
     if (!$id) {
         throw new Error\InvalidRequest("Could not determine which URL to request: " . "class instance has invalid ID: {$id}", null);
     }
     $id = ApiRequestor::utf8($id);
     $fee = ApiRequestor::utf8($fee);
     $base = ApplicationFee::classUrl();
     $feeExtn = urlencode($fee);
     $extn = urlencode($id);
     return "{$base}/{$feeExtn}/refunds/{$extn}";
 }
 public function testList()
 {
     self::authorizeFromEnv();
     $d = ApplicationFee::all();
     $this->assertSame($d->url, '/v1/application_fees');
 }