ci: implement Jest test 4-shard parallel execution

[KubrickCode]

Distribute Jest tests across 4 shards to reduce CI execution time

• Add GitHub Actions matrix strategy for 4 parallel jobs
• Add shard parameter support to justfile
• Upload per-shard coverage artifacts and merge with nyc
• Add JSON reporter to Jest config for coverage merging

fix #200

[gemini-code-assist]

Summary of Changes

Hello @KubrickCode, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces significant improvements to the CI pipeline by enabling parallel execution of Jest tests across four shards. The primary goal is to drastically reduce the overall CI execution time, thereby accelerating the development feedback loop. This is achieved through modifications to the justfile to support sharding and an update to the Jest configuration to facilitate coverage report merging from these parallel runs.

Highlights

• Parallel Test Execution: Implemented a strategy to distribute Jest tests across 4 shards, significantly reducing CI execution time as outlined in the PR description.
• justfile Shard Support: The justfile has been updated to accept an optional shard parameter, enabling the execution of specific test shards and passing this parameter to the underlying pnpm test commands.
• Jest Configuration Update: The Jest configuration for the extension now includes a json reporter in its coverageReporters array, which is essential for collecting coverage data in a format suitable for merging from parallel runs.
• Coverage Merging Preparation: Changes prepare the CI pipeline for uploading per-shard coverage artifacts, a necessary step for merging comprehensive coverage reports using tools like nyc after parallel test runs.

Ignored Files

• Ignored by pattern: .github/workflows/** (1)
  • .github/workflows/test.yml

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[KubrickCode]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces parallel execution for Jest tests by sharding them, which is a great initiative to speed up the CI pipeline. The changes correctly add a shard parameter to the justfile and update the Jest configuration to output JSON coverage reports for merging. I have a couple of suggestions to improve the code. In justfile, the new conditional logic for test execution can be refactored to be more concise and maintainable. In jest.config.cjs, sorting the coverageReporters array would improve consistency with the project's style guide.

[KubrickCode]

🎉 This PR is included in version 0.10.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀