Full-Stack Development Quality Control & Assurance 3

Question 1

What does TDD stand for, and what is its core practice?

Accepted Answer

Test-Driven Development; write tests before writing production code

Answer

TDD (Test-Driven Development) follows a Red-Green-Refactor cycle: write a failing test, make it pass, then clean up the code.

Question 2

In Jest, what does the `beforeEach` hook do?

Accepted Answer

Runs before every individual test in the describe block

Answer

`beforeEach` executes the provided callback function before every single `it`/`test` block within its scope.

Question 3

Which practice involves developers reviewing each other's code before merging to catch defects early?

Accepted Answer

Code review / Pull request review

Answer

Code reviews (pull request reviews) are a QA practice where peers inspect changes for bugs, style issues, and design problems before merge.

Question 4

What is 'mutation testing' used to evaluate?

Accepted Answer

The effectiveness and quality of a test suite

Answer

Mutation testing deliberately introduces small code changes (mutations) and checks whether existing tests detect (kill) those mutations.

Question 5

A Cypress test clicks a button and the assertion fails intermittently. What is this called?

Accepted Answer

A flaky test

Answer

A flaky test is one that produces inconsistent results (pass/fail) without code changes, often due to timing issues or external dependencies.

Full-Stack Development Practice Test