Is this skill compatible with Vitest?

Absolutely. The skill includes specific setup and teardown patterns designed for Vitest, ensuring that mocks are reset between every test run.

How do I handle different API responses for one specific test?

You can use the 'server.use()' method provided in the skill patterns to temporarily override global handlers with specific responses for an individual test case.

Why use MSW instead of mocking fetch or axios directly?

MSW intercepts requests at the network level, which allows your tests to stay decoupled from the specific HTTP client implementation and better reflect real-world browser behavior.

Can I simulate slow network connections with this skill?

Yes, the skill provides patterns for using the MSW delay function to simulate latency, allowing you to reliably test skeleton screens and loading indicators.

MSW API Mocking

Name: MSW API Mocking
Author: yonatangross

byyonatangross

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Security & Testing

Simplifies network-level API mocking for frontend testing using standardized Mock Service Worker (MSW) patterns.

About

This skill provides comprehensive guidance and boilerplate for implementing Mock Service Worker (MSW) in frontend applications, allowing developers to simulate real-world API interactions without mocking low-level fetch or axios calls. It covers setting up global handlers, managing test servers within Vitest or Jest, overriding responses for specific test cases, and simulating complex network conditions like delays or error states, ensuring that tests remain decoupled from implementation details and focused on user-visible behavior.

Key Features

Standardized MSW handler and server setup templates
Realistic network delay simulation for testing loading states
Automated cleanup configurations for testing environments
8 GitHub stars
Dynamic runtime response overrides using server.use()
Detailed error state and status code simulation patterns

Use Cases

Testing UI components that rely on REST API data in isolation
Simulating backend failures to verify frontend error handling logic
Validating complex form submission flows without hitting live endpoints

About

Key Features

Standardized MSW handler and server setup templates
Realistic network delay simulation for testing loading states
Automated cleanup configurations for testing environments
8 GitHub stars
Dynamic runtime response overrides using server.use()
Detailed error state and status code simulation patterns

Use Cases

Testing UI components that rely on REST API data in isolation
Simulating backend failures to verify frontend error handling logic
Validating complex form submission flows without hitting live endpoints