tmux-wrapper 0.1.0

Lightweight tmux automation wrapper and renderer.

tmux-wrapper

tmux-wrapper is a small Python module and CLI for driving a tmux session like a human: type text, press key chords, inspect what changed, and scroll through history.

It is designed for agent workflows, test automation, and other cases where you want a simple tmux control surface instead of shelling out to a large stack of custom tmux commands.

Features

• type(text) sends literal text to the active pane.
• press(chords) sends key chords such as Enter, Ctrl+C, or Ctrl+B Z.
• snapshot() captures the full current screen and resets the diff baseline.
• view() is the recommended inspection API. It returns a contextual, line-oriented delta against the previous capture.
• glance() returns incremental additions plus collapsed ...[N unchanged lines] markers for unchanged regions.
• scroll_up(lines=3) and scroll_down(lines=3) emulate mouse-wheel style scrolling via tmux copy mode.
• tmux-c provides the same workflow from the command line.

Requirements

• Python 3.9+
• tmux installed and available on PATH

Installation

Install from PyPI:

pip install tmux-wrapper

After installation, the CLI command tmux-c is available:

tmux-c 1 glance

Quick Start

Python API

from tmux_wrapper import Keys, TMUXWrapper

tmux = TMUXWrapper(session="demo")

# Establish a baseline for future view()/glance() calls.
tmux.snapshot()

tmux.type("echo hello")
tmux.press([(Keys.Enter,)])
print(tmux.view())

# For a compact "only what was newly added" report:
print(tmux.glance())

tmux.scroll_up(5)
print(tmux.view())

tmux.scroll_down(999)
tmux.delete()

CLI

tmux-c demo snapshot
tmux-c demo type "ls /data"
tmux-c demo press Enter
tmux-c demo view
tmux-c demo glance
tmux-c demo scroll_up 5
tmux-c demo view
tmux-c demo scroll_down 999

How Inspection Works

view() is the default inspection method.

• snapshot() captures the full screen and stores it as the new baseline.
• view() compares the current screen against the previous capture.
• glance() uses the same diff basis, but returns only added lines plus ...[N unchanged lines] markers for unchanged regions.
• Added lines are marked with !!.
• Removed lines are hidden.
• ? helper lines from difflib.ndiff are also hidden.
• If there are no new additions, glance() returns [Nothing Changed].

Example:

!!new output line
  existing prompt context

For compact incremental output, glance() returns abbreviated output such as:

...[12 unchanged lines]
!!new output line
...[3 unchanged lines]

Press Syntax

In Python, press() accepts a list of chords:

tmux.press([(Keys.Enter,)])
tmux.press([(Keys.Ctrl, Keys.C)])
tmux.press([(Keys.Ctrl, Keys.B), (Keys.Z,)])
tmux.press([(Keys.Ctrl, Keys.B), (Keys.Left,)])

In the CLI, each chord is passed as an argument:

tmux-c demo press Enter
tmux-c demo press Ctrl+C
tmux-c demo press Ctrl+B Z
tmux-c demo press Ctrl+B Left

Scrolling

scroll_up() and scroll_down() are line-based helpers built on tmux copy mode.

• scroll_up(lines) enters copy mode and scrolls up by lines.
• scroll_down(lines) scrolls down by lines.
• When scroll_down() reaches the bottom, it exits copy mode automatically.

This matches the intended "mouse wheel with set -g mouse on" feel more closely than page-based movement.

Session Behavior

• TMUXWrapper(session="name") creates the session if it does not already exist.
• If the wrapper created the session, object cleanup will delete it by default.
• Calling delete() always deletes the session immediately.
• CLI snapshot/view/glance state is persisted per session so repeated tmux-c ... calls can diff across separate invocations.

Development

Install development dependencies with uv:

uv sync --dev

Run tests:

env -u VIRTUAL_ENV uv run pytest -q

Notes

• The package focuses on a practical tmux-driving workflow, not a full tmux abstraction layer.
• The renderer captures the full tmux window, not just a single pane.
• The cursor is rendered visibly in full-screen snapshots.