Software Testing

Core Philosophy

Tests exist for one reason: to give you justified confidence that your software does what you intend and won't break what already works when you change it.

The key word is "justified." Confidence without evidence is delusion. A green test suite that doesn't exercise real failure modes is theater. 100% code coverage where every test asserts expect(true).toBe(true) is worse than no tests — it creates false confidence.

The question is never "do we have enough tests?" The question is: "if this change introduced a bug, which test would catch it?" If you can't point to the specific test, you don't have coverage for that behavior — regardless of what the coverage percentage says.

When to Apply