feat: implement /rewind command

[Adib234]

Summary

This PR introduces the /rewind slash command, enabling users to revert their conversation history to a previous point. It supports reverting both the conversation state and any associated file system changes. Additionally, it improves the readability of content included via @ references by wrapping them in clear delimiters.

Details

The new built-in command provides a comprehensive workflow for rewinding a session:

• Interactive Selection: Launches the RewindViewer component (introduced in a separate PR) to let users browse and select a target message.
• Flexible Outcomes: Supports three modes of operation based on user choice:
  1. Rewind Only: Truncates conversation history to the selected point.
  2. Revert Only: Undoes file changes made by the model since the selected point, keeping history intact.
  3. Rewind and Revert: Performs both actions for a complete rollback.
• State Management:
  • Leverages ChatRecordingService to persist the truncated history.
  • Updates the GeminiClient and ContextManager to reflect the new state.
  • Refreshes the UI by reloading the history with loadHistory.

@ Command Processor Updates

• Content Delimiters: Modified handleAtCommand in atCommandProcessor.ts to wrap referenced file content with --- Content from referenced files --- and --- End of content ---.
• Purpose: This clearly demarcates injected context from the user's actual prompt, which is crucial for the RewindViewer to correctly identify and strip this content when displaying past messages.

Integration

• Registers the rewindCommand in BuiltinCommandLoader.ts (implied by file list).
• Updates AppContainer.tsx and types.ts to support the new command structure (implied by file list).

Related Issues

Closes #1769

How to Validate

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 @Adib234, 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 introduces a significant new feature: the /rewind command, which empowers users with greater control over their conversational history within the CLI. This command allows users to jump back to any previous message, effectively resetting the conversation from that point, and can optionally revert any file changes that were made since that message. Alongside this, the way referenced file content is presented in the UI has been improved with distinct headers and footers for better clarity, and the loadHistory mechanism was enhanced to support pre-populating the input field, streamlining the user experience after a rewind operation.

Highlights

• New Rewind Command: Introduces a /rewind command allowing users to navigate and reset their conversation history to a specific point.
• File Reversion Capability: The /rewind command now supports reverting file changes associated with a chosen message, offering options for "Rewind Only", "Rewind and Revert", or "Revert Only".
• Enhanced loadHistory Functionality: The loadHistory function in the UI context has been updated to accept an optional postLoadInput parameter, enabling the input buffer to be pre-filled after loading historical messages.
• Improved Referenced File Display: The @commandProcessor now adds clear "--- Content from referenced files ---" headers and "--- End of content ---" footers around content retrieved from referenced files, enhancing readability.
• Comprehensive Unit Tests: New unit tests have been added for the rewindCommand, ensuring its various functionalities and error handling scenarios are robustly covered.

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[gemini-code-assist]

Code Review

This pull request introduces a new "/rewind" command, enabling users to navigate back to a specific point in their conversation history and optionally revert associated file changes. The implementation correctly integrates with the existing command loading mechanism and UI state management. The changes to atCommandProcessor.ts for handling referenced content headers are also a good improvement for output clarity. The new test file for rewindCommand provides good coverage for various scenarios.

[Adib234]

The implementation of the /rewind command is solid and follows the project's React and testing conventions well.

Actionable Feedback:

• Documentation & Keybindings: In packages/cli/src/config/keyBindings.ts, please add Command.REWIND to the commandCategories (under "History & Search"). This will ensure the shortcut is automatically included in the autogenerated documentation table in docs/cli/keyboard-shortcuts.md when the generation script runs.
• Consistency: While Command.REWIND is mapped to Esc, the double-ESC logic in InputPrompt.tsx still hardcodes the string '/rewind' in the onSubmit call.

Observations:

• Tests: The tests in rewindCommand.test.tsx and RewindViewer.test.tsx correctly use renderWithProviders, waitFor with predicates, and act() where necessary, ensuring stability and adherence to the project's testing standards.
• Typo Fixed: Confirmed that the rewindedConvesation typo has been corrected to rewindedConversation.
• React Patterns: The use of ExpandableText and the integration with BaseSelectionList is consistent with the rest of the CLI's UI architecture.

[Adib234]

commits address the following:

• messages shown from oldest to newest with the latest message selected by default
• additional entry in the history dialog for the current rewind position
• show a message saying "Nothing to rewind to" if /rewind is triggered and there is no history
• The delimiters --- Content from referenced files --- and --- End of content --- are in a constants file
• Removed rewind command integration file, double ESC was documented in keyboard-shortcuts.md in Additional context-specific shortcuts section
• Don't need to deal with resource cleanup because we removed handleClearTextToastChange since we have the toasts we need from this PR 5217045

Consistency: While Command.REWIND is mapped to Esc, the double-ESC logic in InputPrompt.tsx still hardcodes the string '/rewind' in the onSubmit call.

This is consistent with other slash commands

[jacob314]

please revert the comment on line 193. I assume it is an error.

[Adib234]

reverted comment

[jacob314]

nit: having these // Proceed to rewind logic comments i a code smell. Instead call a
rewindConversation helper from both places with this logic. That way it is self documenting.

[Adib234]

Created a helper function

[jacob314]

test files should generally use the raw value not constants. Otherwise it is hard to tell what you are testing.
please revert these test changes using REFERENCE_CONTENT_START and END rather than the raw value.

[Adib234]

Reverted test files

[jacob314]

This PR is good enough to land once the nits mentioned here are addressed.
As a fast follow we should do the following:

1. Ensure the radio button list of rewind locations doesn't wrap around as that is surprising. you should stick to the first message in the history not wrap all the way around to the last.
2. Refresh is broken after changing the history when we are not in alternate buffer mode. There is a force refresh method you should call to resolve this. You can look at what happens when /clear is called if you need a breadcrumb.