Testing

Transcript

1. Testing Oursky Internal Presentation Tuesday, 23 October, 12
2. Why Test? Tuesday, 23 October, 12
3. Faster Time taken to fix bugs 0 250 500 750 1,000 Design Implementation QA Post-release Time taken to fix bugs Tuesday, 23 October, 12
4. Better • Measurable / Indicative Test • Testable Code • Documentation: • Pandaform: Formula / Query Tuesday, 23 October, 12
5. Testable Code = Quality? • Single Responsibility Principle • Number of tests for same functionality • Complexity of the code to test in isolation • Open-Closed Principle / LSP • Possiblility to “mock” an object? • The needs to rewrite test for change? Tuesday, 23 October, 12
6. PaymentServices.charge(50) TEST but Paypal is an external services! PaymentServices.charge(PaypalGateway, 50) => PaymentServices.charge(MockGateway, 50) Tuesday, 23 October, 12
7. TDD • Design -> Implement -> Test • Design -> Test -> Implement Tuesday, 23 October, 12
8. Design? • Spec: hello(n, greeting) print `greeting` for n times Tuesday, 23 October, 12
9. def hello(n, greeting="Hello "): """ return greeting for n times >>> hello(2, "Hello World") 'Hello WorldHello World' """ return n * greeting if __name__ == "__main__": import doctest doctest.testmod() Tuesday, 23 October, 12
10. Design? • What if n is not integer? • How to express “Hello “ is the default argument? Tuesday, 23 October, 12
11. def hello(n, greeting="Hello "): """ return greeting for n times >>> hello(2, "Hello World") 'Hello WorldHello World' n must be an integer >>> hello("Hey", "Hello ") Traceback (most recent call last): ... TypeError: n must be integer By default it repeat "Hello " for n times >>> hello(3) 'Hello Hello Hello ' """ if not isinstance(n, int): raise TypeError("n must be integer") return n * greeting if __name__ == "__main__": import doctest doctest.testmod() Tuesday, 23 October, 12
12. Good Test? • Automated • Run often (everytime you hit :w) • Fast (Mocking DB / External Services / Email) Tuesday, 23 October, 12
13. Other scenarios • Public API • Bug Fixing Tuesday, 23 October, 12
14. Public API • Helps maintain backward compatibility • Test Cross-platform issues Tuesday, 23 October, 12
15. Bug Fixing • Convert bug into test that breaks • Pass the test • Helps prevent edge case & record issue numbers (formflow/tests/models/mysql.txt) Tuesday, 23 October, 12
16. Other issues • Test Coverage • Test Private Code • Helps refactoring vs Change private code will break tests? • DB Test? • Fixtures, Setup / Tear Down • Integrate with version control Tuesday, 23 October, 12
17. Browser Test • Selenium • Watir • Sahi / something else Tuesday, 23 October, 12
18. Selenium IDE Tuesday, 23 October, 12
19. Suggested Todo • Google Testing Blog • Writing Testable Code http://googletesting.blogspot.hk/2008/08/by- miko-hevery-so-you-decided-to.html • Guide to write Testable Code http://misko.hevery.com/attachments/Guide- Writing%20Testable%20Code.pdf • Start writing test in your next project! Tuesday, 23 October, 12