Test-Driven Development (TDD) FAQs

Question 1

When should I activate the TDD skill?

Accepted Answer

Activate it when writing code for new features, starting greenfield projects, sequencing tests for incremental design, or whenever you need to ensure high code quality through a disciplined test-first approach.

Question 2

What are the 'Three Laws' enforced by this skill?

Accepted Answer

The skill follows Uncle Bob's formalization: you shall not write production code without a failing test, you shall not write more of a test than is sufficient to fail, and you shall not write more production code than is sufficient to pass that test.

Question 3

How does the skill help with software design?

Accepted Answer

It 'listens to the tests'—if a test is difficult to write or requires complex setup, the skill identifies this as a design signal and suggests specific refactorings like dependency injection or extracting classes.

Question 4

What is the core cycle of this TDD skill?

Accepted Answer

It follows the classic Red-Green-Refactor cycle: first, write a test that fails for the right reason (Red); second, write the minimal code necessary to make the test pass (Green); and third, clean up the code while keeping the tests passing (Refactor).

Question 5

Does this skill support outside-in development?

Accepted Answer

Yes, it supports the Double-Loop TDD model, which involves writing a failing acceptance test for the 'outer loop' and then using standard TDD for the 'inner loop' to implement the necessary components.

Test-Driven Development (TDD)

Test-Driven Development (TDD)

主な機能

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主な機能

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