Lesson 869 of 1570
AI and Unit Tests: Write Tests That Catch Future You
AI writes solid tests for your functions so you don't break them later when you forget how they work.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The big idea
- 2unit test
- 3Vitest
- 4Jest
Concept cluster
Terms to connect while reading
Section 1
The big idea
A unit test is a small chunk of code that checks one function does what you think it does. AI can write a whole test file for your code in seconds — including the weird edge cases you wouldn't think of.
Some examples
- Ask AI: 'Write Vitest tests for this email-validation function.'
- AI tests the happy path, the empty input, and special characters.
- AI suggests mocking external APIs so tests don't hit the network.
- AI explains a failing test in plain English.
Try it!
Pick a function in a project. Ask AI to write 5 tests for it. Run them and see if any fail (that's how you found a bug).
End-of-lesson quiz
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