Writing a Test Framework From Scratch

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" summary

Starts from assertions-first and implements assert (raising exceptions with caller-filtered backtraces), assert_equal, a float comparator using a 1/1000 delta, then builds tests as methods grouped in classes. Uses the inherited hook to auto-register subclasses, extracts a Reporter class that prints dots and Fs and stores failures, randomizes test order, and returns a clean summary. The result is a working minimal framework in about 70 lines of Ruby that runs quickly and shows all failures rather than stopping at the first.

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" chapters (50)

1. 0:00Intro
2. 0:48Making a Test Framework from Scratch
3. 2:09Introduction
4. 2:27Code Walkthroughs?
5. 3:01Learn Nothing
6. 4:15Starting From Scratch
7. 4:39NOT Minitest
8. 5:07Experiment & Understand
9. 5:20Start with the Assertion
10. 5:40Test framework: complete.
11. 6:16Tradeoffs
12. 7:32def assert test raise RuntimeError, "Failed test", caller unless test
13. 8:42Filter Backtrace
14. 9:43The Rule
15. 10:26Simply works!
16. 10:42Exercise for You
17. 11:04Wrap: Assertions in a Test
18. 11:21Prioritization
19. 11:45Pro: Separate Blocks
20. 12:39Use Methods
21. 12:51Just Use Ruby
22. 14:36Group Methods
23. 15:00Cumbersome
24. 15:14Setup & Teardown?
25. 15:32Reflection & Filtering
26. 16:00Push Up Refactoring
27. 16:24Subclass Test
28. 16:47Auto-Register Tests
29. 17:47Silence is Golden
30. 17:57Trust, But Verify
31. 19:01st Failure : Done
32. 19:33Fixing A Mess, aka Refactoring
33. 19:54Push Down: Exception Handling to Instance Method
34. 20:16Break Up Responsibilities
35. 21:00Run method handles exceptions
36. 21:14Extract: IO to Class Method
37. 21:51Removed all 10 from Test
38. 22:10Quick Fix
39. 22:46rd Argument
40. 22:57Pass Anything!
41. 23:392 arguments
42. 24:12Mixed Types
43. 25:21Separate overview & details
44. 26:27Add: Test Randomization
45. 26:43Tests should always pass regardless of what was run, what order they were run in, or anything else.
46. 28:07slides / 2 loc ?!?!
47. 28:31Run One Test
48. 28:43Failure Handling
49. 29:06Sample Chapter Coming Soon!
50. 29:24Questions?

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