Lesson overview · Free interview practice

Testing Strategies

Learn frontend testing strategies and tools.

Topics in the full lesson
  • Introduction to Testing Strategies
  • Unit Testing with Jest
  • Integration Testing with React Testing Library
  • Best Practices for Testing
  • Practical Examples
  • Exercises

Practice Problems

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TheoryEasy

The Testing Pyramid: Unit, Integration, E2E

Question

What are the three testing levels, and how do you allocate effort across them?

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Explain your reasoning or try an implementation before comparing answers.

TheoryEasy

MSW: Mocking the Network at the Service-Worker Layer

Question

What is MSW, and why has it replaced ad-hoc fetch mocking?

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Explain your reasoning or try an implementation before comparing answers.

TheoryMedium

E2E Testing with Playwright: The Modern Default

Question

How do you write effective E2E tests with Playwright, and what makes it the modern default over Cypress?

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Explain your reasoning or try an implementation before comparing answers.

TheoryMedium

Vitest as the Modern Default (and What Jest Is Still Good For)

Question

What is Vitest, and how does it compare to Jest in modern projects?

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Explain your reasoning or try an implementation before comparing answers.

TheoryMedium

React Testing Library: Test the User, Not the Implementation

Question

What are the canonical RTL best practices, and why do they matter?

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Explain your reasoning or try an implementation before comparing answers.

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