JavaScript Testing and Continuous Integration

jDays 2015

Transcript

1. Mats Bryntse, Bryntum JS Testing and Continuous Integration @Bryntum
2. Intro | PRESENTATION Who am I?
3. Agenda | Content Unit tests UI tests Continuous Integration • Writing a unit test • Using PhantomJS • Hello world sample • Testing a view • Recording a UI test • Application test • TeamCity • Code Coverage • Statistics • Cloud Testing
4. Intro | DESCRIPTION Less Theory, More Real World
5. Intro | WHY Hands up: Who is testing their JS?
6. Intro | WHY
7. Intro | WHY 1. Productivity & confidence in code 2. Frameworks contain bugs 3. So does your code (and mine) 4. Refactoring & code handover 5. Fix bugs once
8. Intro | TERMINOLOGY Terminology: what does testing mean for a JS developer?
9. Intro | TERMINOLOGY Unit tests, UI tests, Application tests..?
10. Intro | Test pyramid JS Unit tests App Tests UI tests
11. Intro | Common company scenario Backend unit tests App Tests
12. Unit Tests Introduction
13. Intro | Unit Tests • should focus on a single JS class (“unit”) • should not involve DOM • is pure logic, runs very fast • is perfect for pre-commit hooks A unit test…
14. Intro | Unit Tests describe('A simple Model test', function (t) {
 
 t.it('Should do something', function(t) { var user = new User({ name : ‘Bob’ });
 t.expect(user.name).toBe(‘Bob’);
 });
 });

15. Intro | Unit Tests describe('A simple Model test', function (t) {
 t.it(‘Will not run', function(t) { … });
 
 t.iit(‘Isolate this section', function(t) { … });
 });

16. Unit tests | Intro •Should be your #1 priority •Cover your most important JS classes, code that is reused •Run often, before commit, daily, nightly. •Use TDD approach + BDD style for readability
17. Unit tests | TDD basics 1. Make the unit test fail 2. Implement 3. Make the test pass 4. Refactor, Repeat
18. Unit tests | Writing a unit test Unit testing demo
19. Testing your UI Functional testing
20. UI tests | Intro Manually writing UI tests takes time
21. UI tests | Intro UI tests are more fragile & run slower than unit tests
22. UI tests | Intro Understanding CSS and ComponentQuery is key
23. UI tests | Intro •UI “unit test” of a single UI component •Or Application test, open index.html and test it Two main types of UI tests
24. UI tests | Intro UI Unit test demo
25. Application Tests Introduction
26. Application tests | Intro •Black box testing, go to index.html… •Runs all the code of your application •Does app work or not?
27. Application tests | Challenges •Database needs to be put in a known state pre test start •Slow •Fragile, race conditions •Errors likely harder to find
28. Application tests | Intro Using an Event Recorder
29. Application tests | Event recorder •Great for application tests •Records user actions: clicks, types, drag drop •Can be used by a non-programmer •Big timesaver
30. Application tests | Event recorder Let’s try the recorder
31. Application tests | Monkey tests Monkey testing
32. Application tests | Monkey tests •Random UI testing •Clicks, drags etc. in your UI •Finds unhandled exceptions •Free testing help. 0€
33. Application tests | Monkey tests Cost breakdown: 5€ * 0 = 0 5€
34. Application tests | Monkey tests Monkey testing demo
35. Application tests | Monkey tests Cheap/Free way to catch bugs
36. Finding bugs | Error logging Error Logging
37. Finding bugs | Error logging Unhandled JS exception: What does the user see?
38. Finding bugs | Error logging Nothing
39. Finding bugs | Error logging win.onerror = function (message, file, line, column, errorObj) { // Log it
 };
40. Finding bugs | Error logging Demo - it’s simple
41. Finding bugs | Git hooks Pre-commit hook
42. Finding bugs | Pre-commit hook •Pre-commit hooks are great to keep code base clean •Check JsHint •Run unit tests
43. Finding bugs | Pre-commit hook A sample Git pre-commit hook
44. Continuous Integration TeamCity, Code Coverage & Statistics
45. Continuous Integration | Intro •Automated builds •Nightly test suite execution •Finding errors early => Code quality => Motivated developers •Enables Continuous Delivery Purpose of having CI:
46. Continuous Integration | Intro Always ready to release!
47. Continuous Integration | Intro •Bryntum uses TeamCity •Test suites run every 2 hours in Chrome •Full test suites executed nightly •Reports, statistics, charts and code coverage
48. Continuous Integration | TeamCity Let’s checkout TeamCity
49. Continuous Integration | Cloud testing So…running in multiple browsers?
50. Continuous Integration | Cloud testing •Need to create Virtual Machines for each version of IE •Total: Chrome, Safari, FF, IE 7-11 => 8 VMs •Managing such a farm can be very time consuming
51. Continuous Integration | Cloud testing •Siesta integrates with both BrowserStack and Sauce Labs •Run tests easily in any OS and Browser combination •No need to setup your own VM farm •Read more on the Bryntum blog…
52. Continuous Integration | Cloud testing Launching tests in BrowserStack
53. Rounding up | Summary •Prioritise JS unit tests •UI tests •Application & monkey tests •Tips for finding errors early •Continuous Integration
54. Rounding up | Links •bryntum.com/products/siesta •bryntum.com/blog •teamcity.bryntum.com/guest •browserstack.com/ •saucelabs.com/
55. Rounding up | Fika Dear Ladies and Gentlemen, 
 
 you are now welcome to ”Vinterträdgården” for a lovely coffee break that is sponsored by
56. Rounding up | Questions Questions? Twitter: @Bryntum