Fix isset($response->field) syntax (#35)

lib/RetailCrm/Response/ApiResponse.php

@@ -121,6 +121,18 @@ class ApiResponse implements \ArrayAccess
         return $this->response[$name];
     }
 
+    /**
+     * Allow to check if the property exists through object property
+     *
+     * @param string $name property name
+     *
+     * @return bool
+     */
+    public function __isset($name)
+    {
+        return isset($this->response[$name]);
+    }
+
     /**
      * Offset set
      *

tests/RetailCrm/Tests/Response/ApiResponseTest.php

@@ -251,4 +251,22 @@ class ApiResponseTest extends TestCase
         $response = new ApiResponse(201, '{ "success": true }');
         unset($response['sssssssuccess']);
     }
+
+    /**
+     * @group unit
+     */
+    public function testMagicIsset()
+    {
+        $response = new ApiResponse(201, '{ "success": true }');
+
+        $this->assertTrue(
+            isset($response->success),
+            'Response object returns property existing'
+        );
+
+        $this->assertFalse(
+            isset($response->suess),
+            'Response object returns property existing'
+        );
+    }
 }