fix(filtered-action-list): respect item renderers

[joshblack]

Closes github/primer#6891

This PR updates FilteredActionList so that item-level renderItem callbacks take precedence over the list-level fallback. Previously, the list renderer was applied after the item props and replaced an item renderer with undefined when no list-level renderer was provided.

Changelog

New

• Add regression coverage for item-level renderers in grouped and ungrouped lists

Changed

• Update FilteredActionList to preserve item-level custom renderers across grouped, virtualized, and standard lists

Removed

• None

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

Testing & Reviewing

The main thing to verify is that item-level renderers override the list-level fallback without changing the existing default rendering path.

• npm run build
• npm run type-check
• npm test -- --run --exclude '.agents/**'
• npm run lint -- --ignore-pattern '.agents/**'
• npm run lint:css -- --ignore-pattern '.agents/**'
• npm run format:diff

[changeset-bot]

🦋 Changeset detected

Latest commit: 360796c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/react	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

⚠️ Action required

👋 Hi, this pull request contains changes to the source code that github/github-ui depends on. If you are GitHub staff, test these changes with github/github-ui using the integration workflow. If this doesn't work, you can also use the original workflow here. Check the integration testing docs for step-by-step instructions. Or, apply the integration-tests: skipped manually label to skip these checks.

To publish a canary release for integration testing, apply the Canary Release label to this PR.

[Copilot]

Pull request overview

This PR fixes FilteredActionList item rendering precedence so that an item’s own renderItem callback overrides the list-level renderItem fallback (including when the list-level fallback is undefined). It also adds regression tests and a patch changeset for release.

Changes:

• Reordered prop spreading for MappedActionListItem usage so item-level renderItem isn’t overwritten by the list-level renderItem.
• Added unit tests for custom item rendering in ungrouped and grouped lists.
• Added a patch changeset for @primer/react.

Show a summary per file

File	Description
packages/react/src/FilteredActionList/FilteredActionList.tsx	Fixes prop precedence so item-level renderItem takes priority over list-level renderItem across grouped/virtualized/standard rendering paths.
packages/react/src/FilteredActionList/FilteredActionList.test.tsx	Adds regression tests for item-level custom rendering behavior.
.changeset/filtered-action-list-item-renderer.md	Declares a patch release note for the behavior fix.

Review details

• Files reviewed: 3/3 changed files
• Comments generated: 1
• Review effort level: Low

[joshblack]

@copilot instead of changing the spread order, explicitly merge the renderItem prop

[Copilot]

@copilot instead of changing the spread order, explicitly merge the renderItem prop

Done in the latest commit. All three MappedActionListItem render paths now use 'renderItem' in item ? item.renderItem : listProps.renderItem to explicitly merge the prop, rather than relying on spread order.

[primer-integration]

Integration test results from github/github-ui PR:

  CI Passed
  VRT Passed
  Projects Passed

All checks passed!