AI and Unit Tests: Write Tests That Catch Future You

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).

Practice this safely

Try this with a school, hobby, or family example where the stakes are low. Use the AI output as a draft you can question, not as the final answer.

1. 1Ask AI to explain unit test in plain language, then underline anything that sounds uncertain or too broad.
2. 2Give it one detail from "AI and Unit Tests: Write Tests That Catch Future You" and ask for two possible next steps plus one reason each step might be wrong.
3. 3Check Vitest against a trusted source, teacher, adult, expert, or original document before you use it.