Principle Test Behavior Not Implementation
backnotprop/pstack/skills/principle-test-behavior-not-implementationby backnotprop3a604672c46cd8187d2b19980eae0a34f9f91138No license1.3K starsListed Oct 9, 2026Updated Oct 9, 2026Repository updated yesterday
Apply when you write, change, or keep a test. Call the code the way its users do and assert the result they observe against a literal expected value. If the test would still pass when every imported function returns undefined, rewrite the assertion or delete the test.
- 3a604672c46cd8187d2b19980eae0a34f9f91138Currentcommit 3a60467Published Oct 9, 2026
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