Multiply your Testing Effectiveness with Parameterized Testing
summary
Covers how pytest parametrization turns four triangle test cases into dozens with one function and demonstrates three concrete techniques: function parameterization, fixture parameterization, and the pytest_generate_tests hook. Uses a small triangle_type example with a deliberate bug, shows generators and CSV-driven cases (collected at collection time), adds readable IDs and markers, and explains running failures and subsets with flags like --lf and -k. Examples and code live on the linked GitHub.
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chapters (28)
- 0:00Intro
- 0:30Brian Okken
- 1:19Value of Tests
- 2:18Parametrize vs Parameterize
- 2:46Something to Test
- 4:11without Parametrization
- 5:02Moving to one test (don't do this)
- 5:47Function Parametrization
- 6:43Parameters from a named list
- 7:16Parameters from a function
- 7:55Parameters from a generator
- 8:13Parameters from a file
- 9:24Run the last failing test case
- 10:20Run test cases with 60 degree angles
- 10:34Run an individual test case
- 10:51Fixture Parametrization
- 11:59Object parameters get non-helpful names
- 12:35An ids function
- 13:22Custom ids function
- 14:03pytest_generate_tests()
- 14:41metafunc
- 15:35test.param
- 16:53indirect parameter
- 17:58indirect example
- 18:38More test cases
- 19:22Review
- 19:37Combining Techniques
- 20:20Resources
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