UndoTree for Sublime Text

A Vim-style UndoTree plugin for Sublime Text 4 (Python 3.8+), visualizing undo history as a branching ASCII tree with live diff previews.

---

Features

• Branching undo history — every save creates a new node; multiple branches supported
• ASCII tree visualization — shows the hierarchy of undo states using indentation and -
• Current node marker — the active undo state is marked with *
• Sequential counters — each node is numbered for easier reference (1 -> +2 -0)
• Live diff preview — highlights changes when navigating the tree
• Restore any state — select a node to restore its content in the editor
• Automatic initial snapshot — captures file content on open
• Lightweight & Python-only — no external dependencies

---

Installation

1. Place the plugin folder into your Sublime Text Packages directory:

   • Linux: ~/.config/sublime-text/Packages/
   • Windows: %APPDATA%\Sublime Text\Packages\
   • macOS: ~/Library/Application Support/Sublime Text/Packages/

2. Restart Sublime Text.

---

Usage

Open UndoTree

• Open the command palette (Ctrl+Shift+P / Cmd+Shift+P) → Show UndoTree
• The tree will appear in a Quick Panel, for example:

*1 -> Initial state
2 -> +2 -0
3 -> +1 -0
4 -> +3 -1
5 -> +1 -2

• * marks the current node
• -> separates the counter from the diff summary

Restore a Node

• Move the selection in the Quick Panel
• Press Enter → restores the editor content to that node
• Hovering over nodes shows a live diff preview in a separate panel

UndoTree Behavior

• Every file save creates a new node
• Branches are automatically tracked if you modify the file from an older state
• Initial file load automatically captures the starting state

---

Example Tree

*1 -> Initial state
2 -> +2 -0
3 -> +1 -0
4 -> +3 -1
5 -> +1 -2

• Shows indentation for branches
• Current node is marked with *
• Numbers help track node order

---

Commands

Command	Description
show_undo_tree	Opens the UndoTree Quick Panel
undo_tree_restore	Restore buffer content to a specific node
undotree_write_preview	Internal: writes live diff preview
undotree_write_panel	Internal: updates ASCII tree panel

---

Requirements

• Sublime Text 4 / 3.8+
• Python 3.8+ (built-in with Sublime Text 4)
• No additional dependencies

---

Notes

• ASCII tree uses spaces and - only for branch visualization, so it works in any font
• Hover preview works with the diff panel
• Branches can be navigated visually, but the Quick Panel does not allow full Vim-style j/k navigation yet