webpack/TESTING_DOCS.md

Webpack Test Suite Structure

This document explains the structure of the test/ directory in the Webpack project using Jest. The directory is organized into multiple folders and files, each serving a specific purpose in testing various aspects of Webpack’s functionality.

Folder and File Breakdown

1. __snapshots__/

• Purpose: Stores Jest snapshot files for comparing output consistency over time.
• Usage: Used for testing UI components, serialized data, or expected module outputs.

2. benchmarkCases/

• Purpose: Contains test cases for benchmarking Webpack's performance.
• Usage: Measures build times, memory usage, and optimization impact.

3. cases/

• Purpose: General test cases covering core functionalities.
• Usage: Includes unit and integration tests for various modules and features.

4. configCases/

• Purpose: Tests related to Webpack configurations.
• Usage: Ensures that Webpack’s configuration (e.g., loaders, plugins) functions correctly.

5. fixtures/

• Purpose: Stores sample/mock data used in tests.
• Usage: Helps in creating consistent test cases with predefined inputs.

6. helpers/

• Purpose: Utility functions and scripts to assist in testing.
• Usage: Provides reusable functions for mock data generation, cleanup, and assertions.

7. hotCases/

• Purpose: Focuses on Webpack’s Hot Module Replacement (HMR) functionality.
• Usage: Ensures live reloading and hot updates work correctly.

8. hotPlayground/

• Purpose: An experimental space for testing HMR features.
• Usage: Allows exploration of new HMR implementations.

9. memoryLimitCases/json

• Purpose: Contains test cases related to memory limits.
• Usage: Ensures Webpack doesn’t exceed memory constraints.

10. statsCases/

• Purpose: Tests focused on Webpack’s statistical outputs.
• Usage: Verifies correct bundle sizes, dependencies, and optimizations.

11. typesCases/

• Purpose: Type-checking tests, likely for TypeScript integration.
• Usage: Ensures proper type definitions and compliance.

12. watchCases/

• Purpose: Tests for Webpack’s watch mode functionality.
• Usage: Ensures file changes trigger correct rebuild behavior.

13. *.unittest.js

• Purpose: Contains unit tests for various functionalities.
• Usage: Ensures individual modules and functions work as expected.

14. BannerPlugin.test.js

• Purpose: Tests Webpack’s BannerPlugin functionality.
• Usage: Ensures that the plugin correctly adds banners to the bundled files.

Testing Framework

• Jest is used for running tests.
• Snapshots help maintain consistency in output.
• Unit tests verify individual module functionality.
• Integration tests ensure multiple components work together.

How to Run Tests

To execute all tests, use the following command:

yarn test

For running specific tests:

jest cases/userLogic.test.js

Contribution Guide

• Add new test cases in the appropriate folder.
• Use Jest assertions and mocks for consistency.
• Run yarn test before pushing changes to validate functionality.