---
id: TASK-027
title: Mouse drag-select in the editor
status: "\U0001F3C1 Done"
assignee: []
created_date: '2026-06-29 23:21'
updated_date: '2026-06-30 04:40'
labels:
  - feature
  - release-1
dependencies: []
priority: medium
ordinal: 27000
---

## Description

<!-- SECTION:DESCRIPTION:BEGIN -->
Implement in-app text selection by mouse: press to anchor, drag (MouseActionMotion) to extend, release to finish — mirroring Shift+arrow selection (respects soft-wrap via MoveToVisual). Currently handleMouse only moves the cursor on left click; there is no drag handling. Also fix the docs/help which already list mouse select as if it works (README Keys table + any in-app help).
<!-- SECTION:DESCRIPTION:END -->

## Acceptance Criteria
<!-- AC:BEGIN -->
- [x] #1 Left press anchors a selection at the click position
- [x] #2 Dragging extends the selection to the pointer (soft-wrap aware)
- [x] #3 Release leaves the selection active; a plain click with no drag clears it and just moves the cursor
- [x] #4 README/help mouse-select claims match actual behavior
<!-- AC:END -->









## Implementation Plan

<!-- SECTION:PLAN:BEGIN -->
1. RED+GREEN editor mouse-select methods: MouseAnchor(vi,col)=MoveToVisual+ClearSelection; MouseExtendTo(vi,col)=startSelection+MoveToVisual (anchor persists across motions). 2. app.handleMouse: Press->MouseAnchor; Motion->MouseExtendTo; plain click no drag leaves no selection. 3. Docs README+help.go mouse drag-select.
<!-- SECTION:PLAN:END -->