Ivan Pashko - Simplifying test automation with design patterns
- 1. Simplifying test automation with design patterns Ivan Pashko
- 2. Speaker info Ivan Pashko, Ukraine Scrum Master in Betsson, Ciklum • 8+ years in the IT • Software Automation Developer /in/ivan-pashko-33208042/ /groups/1180099188730673
- 3. Code smell
- 4. Clean code Code is clean if it can be understood easily – by everyone on the team, going over a long time
- 6. Why Design Patterns? General repeatable solution to a commonly occurring problem in software design.
- 7. Test smells • Test Code Duplication • Conditional Test Logic • Obscure Test • Fragile Test
- 8. Test smells • copy/paste • if-else • inheritance /overrides • data sensivity (hardcode, magic values)
- 9. Test smell. Copy/Paste • Duplication increases the cost of maintenance
- 10. Template Method • Defines the skeleton of an algorithm in an operation, • Deferring some steps to subclasses
- 11. Template Method public class MonitoringNotificationBaseTest<T> where T : BaseNotificationData /// <summary> /// Method perform next steps: /// 1. Create New Notification /// 2. Update Notification /// 3. Check Enable/Disable Button /// 4. Remove Notification /// </summary> /// <param name="defaultNotification">Used in 1 step</param> /// <param name="updatedNotification">Used in 2 step</param> public void CRUDNotificationTest(T defaultNotification, T updatedNotification) { CreateNewNotification(defaultNotification); UpdateNotification(updatedNotification); CheckEnableDisableButton(); RemoveNotification(); }
- 12. Test smell. Conditional Test Logic Makes tests more complicated than they really should be.
- 13. if (element.Exist()) { AssertElementContext(element); } else { AssertErrorMessageAppeared(); } if (element != null) { element.Click(); } • What condition is passed? • What if condition failed, but test is green? • What is test fail? Test smell. Conditional Test Logic
- 14. Strategy Pattern Enables an algorithm's behavior to be selected at runtime
- 15. Factory Pattern • Hides the logic of initializing an object inside the factory. • Refers to the object using a common interface instead of the concrete class.
- 16. Test smell. Inheritance /overrides Blind inheritance and overrides leads to the creation of «Monster» objects
- 17. Composite Pattern • The composite pattern describes a group of objects that is treated the same way as a single instance of the same type of object.
- 18. Decorator Pattern • Attach additional responsibilities to an object dynamically.
- 19. • Revealing Naming • Replace Magic Numbers with constants • Use builder for defaults & complex object creation //Revealing naming List<string> list1 List<string> userNames //Magic numbers as constants FindByAge(33); const int OLD_USER_AGE = 33; FindByAge(OLD_USER_AGE); Test smell. Data sensitivity
- 20. Builder Pattern Separates the construction of a complex object from its representation
- 21. Builder Pattern public class User { //Required parameters: public string Email { get; set; } public string Login { get; set; } //Additional parameters: public string Name { get; set; } public int Age { get; set; } public string Address { get; set; } } • Typical test user object: • Required fields • Additional fields
- 22. Builder Pattern //Telescoping constructor new User(email, login); new User(email, login, "test name", 18, "test address"); //JavaBeans new User("[email protected]", "test_123") { Name = "Name", Age = 18, Address = "test address" }; • Copy / paste • Constructor overrides • Helpers methods As a result: • A lot of code • Duplicates • Unclear defaults
- 23. Builder Pattern new UserBuilder("[email protected]", "user_123") .Name("Name") .Age(18) .Address("test address") .Build(); public UserBuilder(string email, string login) { _user = new User(email, login) { //Default values: Name = "Default Name", Age = 18, Address = "Default address" }; } • Easy to read • Simple to extend • Safe defaults
- 24. Your test smells if • contains if’s • has a ‘twin brother’ • depends on the data • doesn’t feet in one screen • bypass your framework
- 25. Good test is like a good joke - it needs no explanation