Writing a Test Framework from Scratch

on YouTube ↗32m

" summary

Claims how to build a test framework from the atom of assert up to runnable suites using plain Ruby, reimplementing minitest as “microtest” with real code: implements assert_equal and assert_in_delta (1/1000 tolerance), uses raise with caller to fix backtraces, isolates tests via methods and classes, records subclasses with the inherited hook, extracts IO to a Reporter, randomizes with shuffle, and ends with about 70 lines that run ~2x faster than minitest.

AI-written summary · about

" chapters (46)

1. 0:00Making a Test Framework from Scratch
2. 1:47Introduction
3. 2:02Code Walkthroughs?
4. 2:24minitest line by line
5. 3:29Starting from Scratch
6. 3:40Building Your Own Test Framework
7. 3:55NOT Minitest
8. 4:26Experiment & Understand
9. 4:40Start with the Assertion
10. 5:00Test framework: complete.
11. 5:33Tradeoffs
12. 6:53def assert test raise RuntimeError, "Failed test", caller unless test
13. 7:50Unhelpful Failures!
14. 8:09Filter Backtrace
15. 9:11The Rule
16. 10:25Exercise for You
17. 10:41Wrap: Assertions in a Test
18. 10:56Organization
19. 12:41Use Methods
20. 12:51Just Use Ruby
21. 14:43Group Methods
22. 15:24Setup & Teardown?
23. 15:45Reflection & Filtering
24. 16:22Push Up Refactoring
25. 16:49Subclass Test
26. 17:14MyTest Test
27. 18:15Silence is Golden
28. 19:46st Failure : Done
29. 21:07Push Down: Exception Handling to Instance Method
30. 21:32Break Up Responsibilities
31. 22:11Run method handles exceptions
32. 22:27Extract: IO to Class Method
33. 23:40Quick Fix
34. 24:09rd Argument
35. 24:21Pass Anything!
36. 24:32Record Failure
37. 25:082 arguments
38. 25:49Mixed Types
39. 28:07Add: Test Randomization
40. 28:29Rule of Testing
41. 29:16Summary
42. 29:58slides / 2 loc ?!?!
43. 30:18Run One Test
44. 30:30Failure Handling
45. 30:59Sample Chapter Coming Soon!
46. 31:14Questions?

" related talks

• 38mWriting a Test Framework from ScratchRyan Davis · Ruby on Ales 2016
• 32mWriting a Test Framework From ScratchRyan Davis · MountainWest RubyConf 2016
• 39mMiniTest: Refactoring Test Unit and RSpec back to version 0.0.1Jared Ning · RailsConf 2012
• 40mA Guided Read of MinitestNate Berkopec · RubyConf 2015
• 32mMiniTest: Write Awesome TestsMichael J. I. Jackson · MountainWest RubyConf 2012
• 32mA Big Look at MiniTestMark Bates · RubyConf AU 2014
• 33mRuby on Rails on MinitestRyan Davis · RailsConf 2015
• 34mThe history of testing framework in RubyKouhei Sutou · RubyKaigi 2015