Test-Driven Development (TDD) FAQs

Question 1

When should I skip TDD according to this guide?

Accepted Answer

TDD is mandatory for features and bug fixes, but exceptions can be made for throwaway prototypes, generated code, or configuration files, typically after consulting a human partner.

Question 2

How does this skill handle the Refactor phase?

Accepted Answer

Refactoring is only permitted after a test is green. The skill ensures that cleanup, naming improvements, and duplication removal occur without changing the behavior or breaking the existing tests.

Question 3

What is the Iron Law in this TDD skill?

Accepted Answer

The Iron Law dictates that no production code can be written without a failing test existing first. If code is written before the test, the skill mandates deleting it and starting over to ensure the test truly validates the logic.

Question 4

Can I use mocks with this TDD skill?

Accepted Answer

The skill encourages testing real behavior and suggests avoiding mocks unless absolutely unavoidable, as testing mocks can often obscure the actual logic being developed.

Question 5

Why does this skill require watching a test fail?

Accepted Answer

Watching a test fail (the RED phase) confirms that the test is actually checking the intended behavior and that it fails for the right reason, preventing 'green' tests that pass for the wrong reasons.

Test-Driven Development (TDD)

Key Features

Use Cases

Test-Driven Development (TDD)

Key Features

Use Cases