Fix flicker showing message to press ctrl-O again to collapse.

[jacob314]

Summary

Code review feedback for crl-O to expand support as a PR

How to repro: press ctrl-O in regular and alternate buffer mode. Verify the expected messages show and disappear in the expected amount of time.
Fixes #20413

[gemini-cli]

Hi @jacob314, thank you so much for your contribution to Gemini CLI! We really appreciate the time and effort you've put into this.

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[gemini-code-assist]

Summary of Changes

Hello @jacob314, 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 visual flicker in the UI by refactoring how temporary messages are displayed. It consolidates the logic for timed messages into a dedicated custom hook, which streamlines state management and timer handling, leading to a more stable and predictable user experience for transient UI elements.

Highlights

• Refactored Timed Message Logic: The manual state and timer management for displaying temporary messages, such as the 'press Ctrl-O to collapse' hint, has been replaced with a centralized useTimedMessage hook. This change simplifies the component logic and reduces the likelihood of display issues.
• Flicker Fix: The primary goal of this refactoring was to eliminate a flicker that occurred when showing the 'press Ctrl-O again to collapse' message, by ensuring consistent and controlled display timing.
• Improved useTimedMessage Hook: The useTimedMessage hook was enhanced to properly handle null messages, allowing for explicit clearing of a message without inadvertently setting a new timer.

Changelog

• packages/cli/src/ui/AppContainer.tsx
  • Replaced useState and useRef for showIsExpandableHint with useTimedMessage hook.
  • Simplified the useEffect responsible for triggering and clearing the expandable hint.
  • Updated all call sites that previously set showIsExpandableHint or cleared expandHintTimerRef to use the new triggerExpandHint function.
  • Removed a redundant useEffect for queueErrorMessage as its timing is now managed by useTimedMessage.
• packages/cli/src/ui/hooks/useTimedMessage.ts
  • Modified the showMessage callback to accept null as a message, allowing for explicit clearing of the message and preventing a timer from being set when the message is cleared.

Activity

• No specific activity has been recorded for this pull request yet.

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[github-actions]

You already have 7 pull requests open. Please work on getting existing PRs merged before opening more.

[gemini-cli]

Thank you for linking an issue! This pull request has been automatically reopened.

[gemini-code-assist]

Code Review

This pull request is a solid refactoring that replaces manual timer management for UI messages with a new useTimedMessage hook. This change successfully addresses a flickering issue with the overflow hint and improves code clarity by centralizing the logic. I've added a couple of suggestions to further refine the usage of the new hook, ensuring the code's behavior perfectly matches the intent described in the comments and improving efficiency.

[github-actions]

Size Change: -1.48 kB (-0.01%)

Total Size: 25.7 MB

Filename	Size	Change
./bundle/gemini.js	25.2 MB	-1.48 kB (-0.01%)

ℹ️ View Unchanged

Filename	Size
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B
./bundle/sandbox-macos-permissive-open.sb	890 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB
./bundle/sandbox-macos-strict-open.sb	4.82 kB
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB

_{compressed-size-action}

[jwhelangoog]

This comment contains automated feedback from /review-frontend and additional comments from Jarrod based on manual testing.

PR Review for #20414

Summary:
The PR refactors the expansion hint logic to use the useTimedMessage hook, which significantly cleans up AppContainer.tsx. There is one logic detail regarding the new hook's implementation that should be adjusted to avoid unnecessary timers, and a note on ASB behavior.

1. Possible Unnecessary Timer in AppContainer.tsx
In several places (e.g., lines 1230 and 1302), triggerExpandHint(false) is called with the intent to hide the hint and clear the timer.

• Issue: The updated useTimedMessage hook checks if (msg !== null) before starting a timer. Since false is not null, calling triggerExpandHint(false) will clear the current timer but immediately start a new timer to set the state to null after the duration.
• Fix: Change these calls to triggerExpandHint(null). This will clear the message and the timer without starting a new one, correctly fulfilling the intent described in the code comments (e.g., "Explicitly hide the expansion hint and clear its x-second timer").

2. Behavior in Alternate Screen Buffer (ASB)
This change will now show the Ctrl+O hint within the Composer even while in ASB. This was originally unintended (and the previous logic to suppress it was likely the primary cause of the flicker being addressed). Given the changes discussed in issue #20455, this concern may be temporary, but a notable side effect of this fix.

[jwhelangoog]

thanks Jacob