fix(tmux): restore scrollback — history-limit 0 means zero lines not unlimited

[shunkakinoki]

Summary

• history-limit 0 in tmux means zero lines of scrollback (not unlimited), which completely breaks pane scrolling
• This was introduced in fix(tmux): use run-shell guard to prevent duplicate session loggers #934 (c7ae4d77) which mistakenly assumed 0 = unlimited
• Fix: use 2147483647 (max int32), the largest value tmux accepts, giving effectively unlimited scrollable history

Test plan

• Reload tmux config: prefix + t
• Verify scrollback works: produce output, then scroll up with prefix + [

Fixes regression from #934.

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Summary by cubic

Restore tmux scrollback by setting history-limit to 2147483647 (max int) instead of 0, which disabled history. Also fix the fish _tsh_function by adding -- to string replace -r so the '--YYYYMMDD-HHMMSS.txt' regex is parsed correctly.

^{Written for commit 725ed92. Summary will update on new commits.}

[mesa-dot-dev]

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[gemini-code-assist]

Summary of Changes

Hello @shunkakinoki, 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 resolves a critical regression in tmux configurations that resulted in broken pane scrolling. It rectifies an incorrect interpretation of the history-limit setting, ensuring that tmux sessions now provide a substantial scrollback history as intended, thereby restoring expected user functionality.

Highlights

• Tmux Scrollback Fix: Corrected the history-limit setting in tmux from 0 (which means zero scrollback) to 2000000, effectively restoring a large, scrollable history.
• Regression Addressed: Fixed a regression introduced in a previous pull request (fix(tmux): use run-shell guard to prevent duplicate session loggers #934) where history-limit 0 was mistakenly assumed to provide unlimited scrollback, leading to broken pane scrolling.

Changelog

• home-manager/programs/fish/functions/_tsh_function.fish
  • Updated the string replace command to correctly handle file name parsing by adding a -- argument.
• home-manager/programs/tmux/tmux.conf
  • Modified the history-limit setting from 0 to 2000000 to restore proper scrollback functionality.

Activity

• Identified and fixed a regression introduced in PR fix(tmux): use run-shell guard to prevent duplicate session loggers #934.
• Provided a test plan to verify scrollback functionality after applying the fix.

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[coderabbitai]

📝 Walkthrough

Walkthrough

Two minor configuration and syntax adjustments across home-manager programs: a fish shell function receives a syntax fix for argument parsing with the -- separator in string replacement, and tmux configuration increases per-session history retention from 0 to 2,000,000 lines.

Changes

Cohort / File(s)	Summary
Fish Function Syntax Fix home-manager/programs/fish/functions/_tsh_function.fish	Added -- separator after -r flag in string replacement invocation to ensure regex pattern is treated as a literal argument rather than a potential option.
Tmux History Configuration home-manager/programs/tmux/tmux.conf	Increased history-limit from 0 to 2,000,000 to expand per-session history capacity.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Possibly related PRs

• refactor(tmux): flatten tmuxinator dir and improve tsh/tss #935: Also modifies the same fish function file (home-manager/programs/fish/functions/_tsh_function.fish), containing a larger refactor of the same function that may interact with this syntax fix.

Poem

🐰✨ Two tiny fixes, so neat and so fine,
A dash here, a number, the config's divine!
Fish parses correctly, tmux remembers it all,
Small changes that make a big difference, once and for all! 📜

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The PR title accurately describes the main fix: restoring tmux scrollback by clarifying that history-limit 0 means zero lines, not unlimited.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description check	✅ Passed	The description clearly relates to the changeset, explaining the tmux history-limit fix and the fish function syntax correction with supporting context.

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• Post copyable unit tests in a comment
• Commit unit tests in branch fix/tsh-string-replace-pattern

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[mesa-dot-dev]

Mesa Description

TL;DR

Restored tmux scrollback by setting history-limit to the maximum integer value, and fixed the _tsh_function in fish by adding a -- argument to string replace to correctly parse regex patterns.

What changed?

• home-manager/programs/fish/functions/_tsh_function.fish: Modified the string replace command to include a -- argument for correct parsing of regular expressions used to remove timestamp suffixes from filenames.
• home-manager/programs/tmux/tmux.conf: Updated the history-limit to 2147483647 (max int32) to provide effectively unlimited scrollback history in tmux sessions, resolving an issue where 0 mistakenly disabled history.

^{Description generated by Mesa. Update settings}

[cubic-dev-ai]

No issues found across 2 files

[gemini-code-assist]

Code Review

This pull request addresses a regression in the tmux configuration by correcting the history-limit setting. The previous value of 0 disabled scrollback, and this change sets it to a large number to restore it. I have one suggestion regarding the specific value used to ensure it aligns with the intention described in the pull request. A small, unrelated fix in a fish script is also included and appears correct.

[gemini-code-assist]

There's a discrepancy between the value for history-limit mentioned in the pull request description (2147483647) and the one implemented in the code (2000000). To align with the stated goal of using the maximum possible scrollback history that tmux supports, I recommend using the value from the description.

set -g history-limit 2147483647

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@home-manager/programs/tmux/tmux.conf`:
- Line 157: The tmux config currently sets "history-limit" to 2000000 but the PR
states the intended effectively-unlimited value is 2147483647; update the
tmux.conf setting for history-limit (the "set -g history-limit" line) to
2147483647 so the implementation matches the PR intent, or alternatively update
the PR description to state 2000000 if you prefer to keep the current value—make
the change to one of those two places to keep intent and code consistent.

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📥 Commits

Reviewing files that changed from the base of the PR and between 24914ff and 0dd93f1.

📒 Files selected for processing (2)

• home-manager/programs/fish/functions/_tsh_function.fish
• home-manager/programs/tmux/tmux.conf