Testing
Download as PPT, PDF1 like760 views
The document discusses various types of software testing including unit testing, functional testing, system testing, performance testing, and acceptance testing. It provides examples of unit test frameworks for different programming languages. Test-driven development and using continuous integration tools are advocated to improve testing practices and prevent code that does not work from being deployed. Challenges of testing like the difficulty of testing distributed systems are also outlined.
Testing
- 1. Testing Steve Loughran HP Laboratories June 9th, 2008
- 2. About me I break things for a living this is because I am clumsy breaking other people’s code is fun sometimes it is really hard
- 3. Ant in Action the problems of complex builds in big teams not for this course stay in the IDE testing is key to getting big projects out the door automation comes next
- 4. your code doesn't work
- 5. I know this because...
- 6. my code doesn't work
- 7. it's OK to write code that doesn’t work
- 8. but not to ship it
- 9. especially when it matters
- 10. how do you get from "broken" to "shipping"?
- 11. Device Drivers ship and see test it! Test-Driven x: y : f ( y , x) > 0 Formal Methods prove it works
- 12. proofs of correctness shows an algorithm really works good for concurrency and other things you can’t test makes assumptions about system needs lots of maths/CS skills (Pi-Calculus, The HOL System) how do you do regression proofs?
- 13. Testing: code that breaks unit test: test classes, libraries functional test: test the application system test: test a deployed system performance test: simulate load. acceptance tests: is it ready for use? a good test breaks the build!
- 14. Test Driven Development any feature without a test doesn’t exist
- 15. Lots of unit test frameworks Java: JUnit, TestNG Python: PyUnit Ruby: Test:: Unit .NET: NUnit PHP: PHPUnit C++ (CppUnit)
- 16. JUnit main unit test framework in Java (see also TestNG) simple to learn good tool support somewhat low-level extensions for system testing
- 18. public class LessSimpleTest extends TestCase { public LessSimpleTest (String s) { super(s); } public void testAssignment() { final Date date = new Date(); Event event = new Event(UUID.randomUUID(), date, "now", "Text"); assertEquals("self equality failed", event, event); assertEquals(date, event.getDate()); assertNotNull(date.getID()); } }
- 20. Ant-generated report scales better; reports published
- 21. Continuous Integration see: CruiseControl, Hudson, LuntBuild
- 22. ==> blame assignment whose change broke the build?
- 23. System Testing deploy, then: HtmlUnit, XmlUnit, Cactus, Selenium needs automated deployment, database setup, teardown performance testing by comparing timings w.r.t. old runs simulate entire behaviour of the client user/application
- 24. Distributed Systems testing is still a research topic set up complex configurations run tests on remote machines collect results and log data post-mortem analysis virtualization can help see http://tinyurl.com/y99tez
- 25. limitations of testing good tests are hard to write distributed tests very hard different system configurations are still a problem status of "tester" below "coder" A good test breaks the application
- 26. politics: resistance to change
- 27. developers: ignorance, fear E.E.E. Educate, Evangelise, Encourage gently show benefits use testing to track down a bug retain test for regression testing add tests for new code and old problems, not existing codebase adopt cruise control, reporting
- 28. management: ignorance "too much time spent on testing" out of date with modern processes belief that testing slows the schedule (it does on the ship-and-see process) E.E.E., then D.D.D: Distract, Dissemble, Defeat
- 29. call to action write tests use a CI tool: Hudson, Luntbuild, Cruise Control