fix(browser): fix headless config and enable coverage support by fi3ework · Pull Request #922 · web-infra-dev/rstest

fi3ework · 2026-01-29T12:31:36Z

Summary

Prioritize project-level browser configuration (headless, browser name, port) over root config in hostController
Register coverage plugin in browser-mode Rsbuild instance to solve SWC transform registration errors
Synchronize Rsbuild environment name with browser project name to ensure coverage transform mapping
Collect and forward globalThis.__coverage__ data from the browser client to the host
Merge browser coverage results into the global coverage report for both mixed and browser-only runs
Add unit tests for browser config resolution logic
Add E2E tests covering browser-mode coverage for both tested and untested files

Checklist

Tests updated (or not required).
Documentation updated (or not required).

gemini-code-assist · 2026-01-29T12:31:59Z

Summary of Changes

Hello @fi3ework, 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 significantly enhances the browser testing capabilities by addressing configuration precedence and introducing robust code coverage support. It ensures that browser-specific settings are correctly applied and that comprehensive coverage data from browser tests is seamlessly integrated into the overall reporting, improving the reliability and observability of browser-based test suites.

Highlights

Browser Configuration Prioritization: Project-level browser configurations (headless, browser name, port) now take precedence over root configurations within the hostController.
Browser Coverage Plugin Registration: The coverage plugin is now registered in the browser-mode Rsbuild instance, resolving SWC transform registration issues.
Rsbuild Environment Name Synchronization: Rsbuild environment names are synchronized with browser project names to ensure correct coverage transform mapping.
Client-Side Coverage Data Collection: globalThis.__coverage__ data is collected from the browser client and forwarded to the host.
Unified Coverage Reporting: Browser coverage results are merged into the global coverage report, supporting both mixed (browser and node) and browser-only test runs.
New Unit Tests for Config Resolution: Added unit tests to verify the browser configuration resolution logic.
New E2E Tests for Browser Coverage: Added end-to-end tests to cover browser-mode coverage collection for both tested and untested files.

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gemini-code-assist

Code Review

This pull request effectively adds coverage support for browser tests and fixes browser configuration resolution. The changes are well-structured, and the inclusion of both E2E and unit tests is great. I've found one potential issue related to how results are merged in watch mode when both browser and node tests are present.

packages/core/src/core/runTests.ts

Copilot

Pull request overview

This PR fixes browser mode coverage collection (issue #917) by implementing proper coverage plugin registration, configuration prioritization, and data collection flow for browser tests.

Changes:

Enables coverage plugin registration in browser-mode Rsbuild instances with proper configuration mapping
Prioritizes project-level browser configuration over root configuration for headless mode, browser selection, and port settings
Implements coverage data collection from browser tests and merges results with node tests for unified reporting

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/core/src/core/runTests.ts	Adds coverage generation for browser-only test runs and merges browser results with node results for mixed test environments
packages/core/src/browser.ts	Exports `loadCoverageProvider` function to enable browser package to load coverage providers
packages/browser/tests/hostController.test.ts	Adds unit tests to verify project-level browser config properly overrides root config
packages/browser/src/hostController.ts	Implements project-level config prioritization, registers coverage plugin, and synchronizes environment name with project name
packages/browser/src/client/entry.ts	Collects coverage data from `globalThis.__coverage__` and attaches it to test file results
e2e/browser-mode/fixtures/ports.ts	Adds port configuration for browser-coverage E2E test fixture
e2e/browser-mode/fixtures/browser-coverage/tests/sum.test.ts	Adds E2E test for a file with coverage
e2e/browser-mode/fixtures/browser-coverage/src/sum.ts	Adds tested source file for coverage E2E validation
e2e/browser-mode/fixtures/browser-coverage/src/multiply.ts	Adds untested source file for coverage E2E validation
e2e/browser-mode/fixtures/browser-coverage/rstest.config.ts	Configures browser mode with coverage enabled for E2E testing
e2e/browser-mode/coverage.test.ts	Validates browser coverage collection for both tested and untested files

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e2e/browser-mode/coverage.test.ts

packages/browser/src/client/entry.ts

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

github-actions bot added the change: fix label Jan 29, 2026

gemini-code-assist bot reviewed Jan 29, 2026

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packages/core/src/core/runTests.ts Outdated Show resolved Hide resolved

fix(browser): fix headless config and enable coverage support

7b0eedd

fi3ework force-pushed the max/2026-01-29--20-27 branch from 9b8a45c to 7b0eedd Compare January 29, 2026 12:45

fi3ework marked this pull request as ready for review January 29, 2026 15:03

Copilot AI review requested due to automatic review settings January 29, 2026 15:03

Copilot started reviewing on behalf of fi3ework January 29, 2026 15:03 View session

Copilot AI reviewed Jan 29, 2026

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e2e/browser-mode/coverage.test.ts Outdated Show resolved Hide resolved

e2e/browser-mode/coverage.test.ts Outdated Show resolved Hide resolved

packages/browser/src/client/entry.ts Outdated Show resolved Hide resolved

fi3ework and others added 3 commits January 29, 2026 23:12

Update e2e/browser-mode/coverage.test.ts

c5ac50d

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Update packages/browser/src/client/entry.ts

e96e2d8

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

1

bc01cfc

fi3ework force-pushed the max/2026-01-29--20-27 branch from fa3cc0c to bc01cfc Compare January 29, 2026 16:15

fi3ework enabled auto-merge (squash) January 29, 2026 16:16

fi3ework merged commit 01a0f3a into main Jan 29, 2026
15 of 17 checks passed

fi3ework deleted the max/2026-01-29--20-27 branch January 29, 2026 16:45

fi3ework mentioned this pull request Feb 3, 2026

release: 0.8.2 #931

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fix(browser): fix headless config and enable coverage support#922

fix(browser): fix headless config and enable coverage support#922
fi3ework merged 4 commits intomainfrom
max/2026-01-29--20-27

fi3ework commented Jan 29, 2026 •

edited

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fi3ework commented Jan 29, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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fi3ework commented Jan 29, 2026 •

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