fix(cli): correct shell height reporting

[jacob314]

Summary

Shells are now rendered in a small box in Gemini CLI but we were still telling nodepty that they had
a much larger height making them unusable.

Details

Report the correct height and width and simplify so reporting is done from the UI components
themselves rather than AppContainer. The logic has been correctly relocated to ShellToolMessage.tsx.

Related Issues

Fixes #21494

How to Validate

Run vim, gemini or other interactive apps from with the embedded shells. Verify that the shell now
renders at the expected height and width.

[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.

We're making some updates to our contribution process to improve how we track and review changes. Please take a moment to review our recent discussion post: Improving Our Contribution Process & Introducing New Guidelines.

Key Update: Starting January 26, 2026, the Gemini CLI project will require all pull requests to be associated with an existing issue. Any pull requests not linked to an issue by that date will be automatically closed.

Thank you for your understanding and for being a part of our community!

[gemini-code-assist]

Summary of Changes

Hello, 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 refines the terminal UI's shell height management to ensure accurate display and interaction. It introduces a more precise calculation for the available vertical space within the shell, accounting for UI elements like borders and headers. This change centralizes the PTY resizing logic, leading to a more robust and predictable user experience, especially when dealing with varying terminal sizes and shell outputs.

Highlights

• Improved Shell Height Calculation: The system now accurately accounts for UI overhead, such as borders and titles, when determining the available height for shell content, preventing display issues.
• Refactored PTY Resizing Logic: The logic for resizing the pseudo-terminal (PTY) has been centralized within the ShellToolMessage component, ensuring consistent and correct shell dimensions during execution.
• Enhanced Text Wrapping in ANSI Output: Text within ANSI output is now configured to wrap, improving readability for long lines of shell output.
• Removed Redundant Tests: Outdated test blocks related to previous terminal height calculation and shell interaction logic have been removed, streamlining the test suite.

Changelog

• packages/cli/src/ui/AppContainer.test.tsx
  • Removed unused imports related to terminal size and shell execution.
  • Deleted test blocks for 'Terminal Height Calculation' and 'Shell Interaction'.
• packages/cli/src/ui/AppContainer.tsx
  • Removed a useEffect hook responsible for resizing the PTY based on terminal dimensions.
• packages/cli/src/ui/components/AnsiOutput.tsx
  • Enabled text wrapping for AnsiLineText component to improve display of long lines.
• packages/cli/src/ui/components/snapshots/AskUserDialog.test.tsx.snap
  • Updated test snapshots for AskUserDialog to reflect changes in interaction instructions and removed redundant warning messages.
• packages/cli/src/ui/components/messages/ShellToolMessage.test.tsx
  • Adjusted expected maximum line calculations and assertions in ShellToolMessage tests to account for new shell content overhead.
• packages/cli/src/ui/components/messages/ShellToolMessage.tsx
  • Added imports for ShellExecutionService, CoreToolCallStatus, calculateToolContentMaxLines, and SHELL_CONTENT_OVERHEAD.
  • Introduced a new useEffect hook to handle PTY resizing for executing shells, calculating childWidth and finalHeight.
  • Refactored maxLines calculation to use a new maxLines constant.
• packages/cli/src/ui/utils/toolLayoutUtils.ts
  • Introduced SHELL_CONTENT_OVERHEAD constant to define vertical space consumed by shell UI elements.
  • Updated calculateShellMaxLines to factor in SHELL_CONTENT_OVERHEAD for more accurate shell height calculations in various scenarios.

Activity

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

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[gemini-code-assist]

Code Review

This pull request refactors the shell height calculation and PTY resizing logic, moving it from AppContainer to the more specialized ShellToolMessage component. This is a positive change for modularity. The introduction of a constant for UI overhead is also a good step towards fixing height miscalculations. However, I've identified a critical issue where inconsistent height calculation methods are used for the display component and the underlying PTY, which could lead to UI rendering bugs. My review includes a suggestion to resolve this inconsistency, aligning with our guidelines for maintaining layout consistency.

[github-actions]

Size Change: +345 B (0%)

Total Size: 26 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	25.5 MB	+345 B (0%)
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B	0 B
./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}