Test-Driven Development (TDD) FAQs

Question 1

Why does this skill insist on deleting code written before a test?

Accepted Answer

Writing code before a test leads to confirmation bias. Deleting and restarting ensures the test actually has the power to fail, proving it is truly verifying the behavior rather than just passing because the code already exists.

Question 2

Can I use the TDD skill for fixing bugs?

Accepted Answer

Absolutely. The recommended workflow is to write a failing test that reproduces the bug, verify the failure, and then write the minimal code required to make the test pass.

Question 3

What happens if my test passes immediately during the RED phase?

Accepted Answer

If a test passes immediately, you aren't testing a new behavior or a bug. You must either fix the test so it correctly targets the missing functionality or acknowledge that the behavior already exists.

Question 4

Is TDD slower than writing tests after the code?

Accepted Answer

While it may feel slower upfront, TDD drastically reduces time spent on debugging and fixing regressions later in the lifecycle, making the overall development process faster and more predictable.

Question 5

Does this skill work with any programming language?

Accepted Answer

Yes, the TDD skill provides a conceptual framework and set of rules that apply to any language or testing framework, including TypeScript, Python, Go, and more.

Test-Driven Development (TDD)

Key Features

Use Cases

Test-Driven Development (TDD)

Key Features

Use Cases