chore: upgrade vitest to 4

[btea]

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Summary by CodeRabbit

• Chores
  • Upgraded testing and coverage tooling to Vitest v4 and removed legacy coverage tooling.
  • Simplified test configuration and removed a workspace entrypoint used for test orchestration.
  • Adjusted CI workflow triggers: one workflow now supports manual dispatch and broader PR triggers; another now restricts PR runs to the main branch.

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[github-actions]

[coderabbitai]

📝 Walkthrough

Walkthrough

Removed the master-branch constraint from the test-coverage workflow, added a master-only branch filter to the publish-size-report workflow, upgraded Vitest-related devDependencies to v4 and removed c8, removed testTransformMode and coverage.include from vitest.config.mts, and deleted the Vitest workspace file.

Changes

Cohort / File(s)	Summary
Workflow changes .github/workflows/test-coverage.yml, .github/workflows/publish-size-report.yml	test-coverage.yml: removed the master branch filter from pull_request triggers (now responds to PRs and workflow_dispatch). publish-size-report.yml: added a pull_request branch filter to only trigger for master.
Test dependency updates package.json	Bumped devDependencies: vitest, @vitest/coverage-v8, @vitest/ui from ^2.0.5 → ^4.0.16; removed devDependency c8.
Vitest config changes vitest.config.mts	Removed testTransformMode mapping and removed coverage.include patterns from the exported config.
Workspace removal vitest.workspace.ts	Deleted the default workspace export (defineWorkspace(['./vitest.config.mts'])) and its import — workspace entrypoint removed.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐰 I hopped through configs, tidy and neat,
Dependencies bumped, old tools beat retreat.
Workflows adjusted, branches set right,
Workspace tucked in, tests take the light.
A tiny rabbit cheers the merge tonight. 🎉

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The PR description contains only the template checklist with all items unchecked and no actual description of the changes, objectives, or reasoning for the upgrade.	Replace the template checklist with a meaningful description explaining why Vitest is being upgraded, what changes are involved, and any testing or validation performed.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: upgrading Vitest from version 2 to version 4 across the test tooling setup.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch chore/upgrade-vitest-4

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📜 Recent review details

Configuration used: defaults

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 70c3cf5 and e3bb609.

📒 Files selected for processing (1)

• vitest.config.mts

💤 Files with no reviewable changes (1)

• vitest.config.mts

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (9)

• GitHub Check: Unit Test (New)
• GitHub Check: build
• GitHub Check: Coverage
• GitHub Check: Unit Test (Current)
• GitHub Check: Unit Test (LTS)
• GitHub Check: SSR rendering test
• GitHub Check: Lint
• GitHub Check: Build ubuntu-latest LTS
• GitHub Check: Build windows-latest LTS

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[pkg-pr-new]

Open in StackBlitz

pnpm add https://pkg.pr.new/element-plus/element-plus@23223

npm i https://pkg.pr.new/element-plus/element-plus@23223

yarn add https://pkg.pr.new/element-plus/element-plus@23223.tgz

commit: e3bb609

[github-actions]

🧪 Playground Preview: https://element-plus.run/?pr=23223
Please comment the example via this playground if needed.

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	85.38%	17789 / 20833
🔵	Statements	84.18%	18618 / 22116
🔵	Functions	83.79%	4793 / 5720
🔵	Branches	73.66%	10171 / 13808

File Coverage

No changed files found.

Generated in workflow #386

[github-actions]

@btea Thanks for your contribution! ❤️