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Notes/Jest: Isolation, Mocks and a Suite That Lasts/Sources

Testing

Jest: Isolation, Mocks and a Suite That Lasts

25 chapters · GrafSoul

1Installation and Config
2Your First Test: test, expect and the Red-Green Loop
3What and How to Test: the Unit, Input-Output, AAA
4TypeScript and ESM
5Structure That Explains Behavior
6Setup and Teardown: Lifecycle Hooks and Order
7Precise Matchers
8Isolation and Asynchrony
9Mock Functions
10Spies: jest.spyOn and Restoration
11Module Mocks
Mocking the Network: MSW Instead of Mocking fetch

12

13Clocks and Timers

14React Through the User's Eyes

15Testing Custom Hooks: renderHook

16Next.js: next/jest

17Backend: Real Boundaries

18Snapshots as a Contract

19Coverage: Execution, Not Quality

20Projects: Environments and Packages

21Patterns for a Durable Suite

22Debugging Tests

23Flaky Is a Defect, Not Weather

24CI: Reproducibility and Feedback

25Checking a Professional Test

Chapter 27

Sources

Links

Jest - Documentationjestjs.io
Jest - Configuring Jestjestjs.io
Jest - Mock Functionsjestjs.io
Jest - Timer Mocksjestjs.io
Jest - Snapshot Testingjestjs.io
Testing Library - Reacttesting-library.com
Testing Library - Guiding Principlestesting-library.com
Next.js - Testing with Jestnextjs.org
MDN Web Docs - JavaScriptdeveloper.mozilla.org

← Chapter 26

Sources - grafsoul