test: migrate to Rstest

[chenjiahan]

https://github.com/web-infra-dev/rstest

[gemini-code-assist]

Summary of Changes

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This pull request undertakes a comprehensive migration of the project's testing framework from Jest to Rstest. The primary goal is to modernize the testing setup, leveraging Rstest's capabilities for improved performance and maintainability. The changes span across configuration files, package scripts, test utility functions, and snapshot formats, ensuring a smooth transition while preserving existing test coverage and behavior.

Highlights

• Testing Framework Migration: Migrated the project's testing infrastructure from Jest to Rstest, involving significant changes to configuration, scripts, and test utilities.
• Configuration Updates: Removed the jest.config.js file and introduced a new rstest.config.mjs file to define Rstest's configuration, including test environment, globals, and file patterns.
• Build Script Refinements: Updated package.json scripts to remove Jest-specific commands and integrate Rstest for running tests, including watch mode.
• Test Setup Adaptation: Modified setupTest.js to configure Rstest's test timeout and provide compatibility layers for existing 'done-style' asynchronous tests by patching it and test global functions.
• Snapshot Migration: Migrated existing Jest snapshot files to the Rstest snapshot format, ensuring continuity of snapshot testing.
• ES Module Conversion: Converted the scripts/globalSetup.js file to an ES module (.mjs) and updated its export syntax.
• Middleware Test Enhancements: Improved the robustness of middleware.test.js by updating Stats import to ES module syntax, adding a helper for dynamic asset filename retrieval, and using expect.objectContaining for more flexible test assertions.

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Changelog

• jest.config.js
  • Removed Jest configuration file.
• package.json
  • Removed Jest-specific test scripts (test:only, test:coverage).
  • Updated test:watch and test scripts to use Rstest.
  • Removed jest and babel-jest from dev dependencies.
  • Added @rstest/core to dev dependencies.
• rstest.config.mjs
  • Added new Rstest configuration file, defining test environment, globals, and file inclusion/exclusion patterns.
• scripts/globalSetup.js
  • Renamed to scripts/globalSetup.mjs.
  • Converted from CommonJS to ES module syntax.
  • Changed anonymous function export to a named setup export.
• setupTest.js
  • Replaced jest.setTimeout with rstest.setConfig for test timeout configuration.
  • Assigned rstest to globalThis.jest for compatibility.
  • Implemented wrapDoneStyleTest and patchTestApi to support 'done-style' asynchronous tests with Rstest's API, including only, skip, concurrent, and each methods.
• test/snapshots/logging.test.js
  • Removed old Jest snapshot file.
• test/snapshots/logging.test.js.snap
  • Added new Rstest snapshot file with updated format.
• test/logging.test.js
  • Removed Jest test file, implying its content was refactored or integrated into the new Rstest setup.
• test/middleware.test.js
  • Updated Stats import from CommonJS require to ES module import.
  • Added getAssetFilename helper function to dynamically retrieve asset filenames from compiler stats.
  • Modified expect.toEqual assertions for watch options to use expect.objectContaining for increased test flexibility.
  • Updated immutable cache tests to use the new getAssetFilename helper and ensure main.js is requested before SVG assets.
• test/utils/snapshots/setupHooks.test.js
  • Removed old Jest snapshot file.
• test/utils/snapshots/setupHooks.test.js.snap
  • Updated snapshot header and test names to Rstest format.
• test/utils/snapshots/setupWriteToDisk.test.js
  • Removed old Jest snapshot file.
• test/utils/snapshots/setupWriteToDisk.test.js.snap
  • Updated snapshot header and test names to Rstest format.
• test/utils/ready.test.js
  • Updated the expectation for context.logger.info to dynamically use cb.name instead of a hardcoded string, improving test robustness.

Activity

• The pull request author, chenjiahan, initiated the migration to Rstest.
• The changes involve a significant refactoring of the testing setup, including configuration, dependencies, and test utilities.

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[gemini-code-assist]

Code Review

This pull request migrates the project's testing framework from Jest to Rstest. The changes include removing Jest's configuration and dependencies, adding the Rstest configuration, and updating test-related scripts and setup files. A compatibility layer has been added to support Jest's done() callback syntax in asynchronous tests, which is a good approach for a smooth migration.

However, I've found a critical issue in package.json where the test script is defined recursively, which will cause an infinite loop.

Additionally, the large test file test/logging.test.js has been removed entirely. Migrating to a new test runner should not result in a reduction of test coverage. This file should be migrated to Rstest instead of being removed.

[Copilot]

Pull request overview

This PR migrates the test setup from Jest to @rstest/core, updating test bootstrapping, snapshots, and a few test expectations to align with the new runner.

Changes:

• Replace Jest configuration with rstest.config.mjs and update global test setup (setupTest.js).
• Update/replace snapshot files to the new snapshot format and namespacing.
• Adjust a few tests for stability (e.g., less strict option object comparisons; dynamic asset filename selection).

Reviewed changes

Copilot reviewed 14 out of 16 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
test/utils/ready.test.js	Adjusts expectation to use callback function name dynamically.
test/utils/snapshots/setupWriteToDisk.test.js.snap	Updates snapshots to new runner’s snapshot format/keys.
test/utils/snapshots/setupWriteToDisk.test.js	Removes legacy snapshot artifact file.
test/utils/snapshots/setupHooks.test.js.snap	Updates snapshots to new runner’s snapshot format/keys.
test/utils/snapshots/setupHooks.test.js	Removes legacy snapshot artifact file.
test/middleware.test.js	Updates imports, loosens a few assertions, and makes immutable-asset tests resilient by deriving the emitted SVG name from stats.
test/logging.test.js	Removes the logging integration test file.
test/snapshots/logging.test.js.snap	Adds new snapshot file for logging tests (but corresponding test file is missing).
test/snapshots/logging.test.js	Removes legacy snapshot artifact file.
setupTest.js	Replaces Jest timeout setup with rstest config and wraps done-style tests for compatibility.
scripts/globalSetup.mjs	Converts global setup to ESM and exports a setup() hook.
rstest.config.mjs	Adds rstest configuration (environment, include/exclude, setup/global setup files).
pnpm-lock.yaml	Removes Jest deps and adds rstest (and coverage plugin) lock entries.
package.json	Updates devDependencies for rstest and modifies test scripts (currently broken).
jest.config.js	Removes Jest configuration.

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