javascript-testing-patterns

Implement comprehensive testing strategies using Jest, Vitest, and Testing Library for unit tests, integration tests, and end-to-end testing with mocking, fixtures, and test-driven development. Use when writing JavaScript/TypeScript tests, setting up test infrastructure, or implementing TDD/BDD workflows.

Quality

71%

Does it follow best practices?

Impact

Pending

No eval scenarios have been run

Securityby

Passed

No known issues

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Evaluation results

78%

21%

Weather Alert Service Testing Setup

Vitest config and module mocking

Criteria

Without context

With context

Globals enabled

100%

Node environment

100%

Coverage provider v8

100%

Coverage reporters

62%

100%

Coverage excludes

100%

Setup files

NPM test scripts

25%

100%

vi.mock factory pattern

vi.clearAllMocks in beforeEach

12%

62%

Async/await tests

100%

Rejects assertion

100%

Edge cases tested

100%

Product Inventory Service: Unit Testing with Reusable Test Data

Test fixtures and dependency injection

Criteria

Without context

With context

Faker package used

100%

Factory with overrides

100%

Array factory function

100%

DI interface defined

100%

Mock via constructor

100%

vi.mocked() usage

100%

Nested describe blocks

100%

beforeEach fresh instance

100%

Descriptive test names

100%

Error path tests

100%

TypeScript types in tests

100%

66%

React Notification System: Component and Hook Testing

React Testing Library and timer mocking

Criteria

Without context

With context

Testing Library imports

100%

Semantic queries used

100%

No data-testid overuse

100%

renderHook usage

100%

act() wrapping

25%

Snapshot testing

vi.useFakeTimers called

100%

vi.advanceTimersByTime used

100%

vi.useRealTimers restored

100%

vi.spyOn method spy

mockRestore in afterEach

Repository: Dicklesworthstone/pi_agent_rust
Commit: 47823e3

Evaluated: about 1 month ago
Agent: Claude Code
Model: Claude Sonnet 4.6

Table of Contents

Weather Alert Service Testing Setup Product Inventory Service: Unit Testing with Reusable Test Data React Notification System: Component and Hook Testing

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