Test-driven development (TDD) in Software Engineering - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Test-driven development (TDD)?

TDD is a software development approach where tests are written before writing the actual code. It helps ensure the code works as expected by guiding development through tests.

beginner

What are the three main steps in the TDD cycle?

The three steps are: 1) Write a failing test, 2) Write code to pass the test, 3) Refactor the code to improve it while keeping tests passing.

intermediate

Why is writing tests first beneficial in TDD?

Writing tests first helps clarify what the code should do, prevents overcoding, and ensures that every piece of code is tested from the start.

intermediate

How does TDD improve software quality?

TDD improves quality by catching bugs early, encouraging simple design, and providing a safety net for future changes through automated tests.

beginner

What is refactoring in the TDD process?

Refactoring means improving the code's structure and readability without changing its behavior, done after tests pass to keep code clean and maintainable.

What is the first step in the TDD cycle?

A Refactor the code

B Write the full code

C Run all tests

D Write a failing test

In TDD, you start by writing a test that fails because the feature is not implemented yet.

Why do developers refactor code after writing tests in TDD?

A To improve code without changing behavior

B To add new features

C To remove tests

D To make tests fail

Refactoring improves code quality and readability without changing what the code does.

Which of the following is NOT a benefit of TDD?

A Faster initial coding without tests

B Early bug detection

C Clear requirements

D Better code design

TDD requires writing tests first, so initial coding is not faster but leads to better quality.

In TDD, what does a passing test indicate?

A The test is incorrect

B The code meets the test requirements

C The code needs more features

D The test should be deleted

A passing test means the code behaves as expected for that test case.

How does TDD help with future code changes?

A By removing old code

B By delaying testing until the end

C By providing automated tests as safety checks

D By avoiding writing tests

Automated tests created during TDD help ensure future changes do not break existing functionality.

Explain the Test-driven development (TDD) cycle and why each step is important.

Think about how tests guide coding and how refactoring keeps code clean.

Describe the main benefits of using TDD in software development.

Consider how tests help both during and after development.