fix(ui): preventing empty history items from being added

[devr0306]

Summary

This pull request addresses the issue of empty history items being added to the history items list.

Details

In handleContentEvent in useGeminiStream.ts, empty history items were being added due to findLastSafeSplitPoint returning 0 for code content within code blocks. So, for larger code blocks, addItem was called multiple times with an empty string before the actual content could get added. This led to extra space being rendered above the code blocks.

Related Issues

Fixes #18452

How to Validate

1. Enter alternate buffer mode and ask "Without calling any tool, show me an example java class"
2. Exit alternate buffer mode and ask the same thing

Both cases should display content without extra spaces

Pre-Merge Checklist

• Updated relevant documentation and README (if needed)
• Added/updated tests (if needed)
• Noted breaking changes (if any)
• Validated on required platforms/methods:
  • MacOS
    • npm run
    • npx
    • Docker
    • Podman
    • Seatbelt
  • Windows
    • npm run
    • npx
    • Docker
  • Linux
    • npm run
    • npx
    • Docker

[gemini-code-assist]

Summary of Changes

Hello @devr0306, 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 addresses a user interface rendering anomaly where empty history items were inadvertently displayed, leading to unnecessary vertical spacing. By implementing a filtering mechanism, the application now correctly omits these empty entries, resulting in a cleaner and more compact display of historical content.

Highlights

• UI Rendering Fix: Empty history items, specifically 'gemini_content' with no text, are now filtered out to prevent them from being rendered.
• Space Reduction: This change resolves an issue where empty history items caused extra vertical space above rendered content in the UI.

Changelog

• packages/cli/src/ui/components/MainContent.test.tsx
  • Added a new test case to verify that empty history items are not rendered.
• packages/cli/src/ui/components/MainContent.tsx
  • Implemented a filter within the 'historyItems' useMemo hook to exclude 'gemini_content' items that have no text.
  • Applied the same filtering logic to the 'virtualizedData' useMemo hook to ensure empty history items are not included in the virtualized list.
• packages/cli/src/ui/components/snapshots/MainContent.test.tsx.snap
  • Updated the snapshot to reflect the new test case for not rendering empty history items.
• packages/cli/src/ui/utils/MarkdownDisplay.tsx
  • Corrected a typo from "to long" to "too long" in a comment.

Activity

• The author has added a new test case to validate the fix for empty history items.
• The author has validated the changes on MacOS using 'npm run'.
• Instructions for validating the fix have been provided, including steps to reproduce the original issue and confirm its resolution in both alternate buffer mode and regular mode.

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[gemini-code-assist]

Code Review

This pull request effectively addresses the issue of empty history items being rendered by filtering them out before they are passed to the UI components. The addition of a new test case ensures this behavior is covered and prevents regressions. My main feedback is to refactor the duplicated filtering logic into a separate useMemo hook to improve code maintainability and reduce the chance of future bugs.

[devr0306]

From /review-frontend:

LGTM! The fix effectively filters out empty history items, resolving the extra spacing issue. The added test case correctly verifies this behavior using the established testing patterns. Thanks for the cleanup in MarkdownDisplay.tsx as well.

[github-actions]

Size Change: +61 B (0%)

Total Size: 24.5 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	24.5 MB	+61 B (0%)
./bundle/sandbox-macos-permissive-open.sb	890 B	0 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB	0 B
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB	0 B
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB	0 B
./bundle/sandbox-macos-strict-open.sb	4.82 kB	0 B
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB	0 B

_{compressed-size-action}

[jacob314]

[jacob314]