---
id: T04
parent: S02
milestone: M002
provides: []
requires: []
affects: []
key_files: ["app/src/views/DesignCanvas.tsx"]
key_decisions: ["Keyboard shortcuts use window-level keydown listener with activeElement tag guard to skip input/textarea/select", "Ctrl+Shift+Z checked before Ctrl+Z to avoid false undo on redo shortcut"]
patterns_established: []
drill_down_paths: []
observability_surfaces: []
duration: ""
verification_result: "npx tsc --noEmit: zero errors (exit 0). npx vitest run --reporter=verbose: 71 tests pass across 6 test files (exit 0)."
completed_at: 2026-03-26T05:41:35.156Z
blocker_discovered: false
---

# T04: Add canvas keyboard shortcuts (undo/redo/delete/select-all/deselect) and verify full integration — 71 tests pass, zero TypeScript errors

> Add canvas keyboard shortcuts (undo/redo/delete/select-all/deselect) and verify full integration — 71 tests pass, zero TypeScript errors

## What Happened
---
id: T04
parent: S02
milestone: M002
key_files:
  - app/src/views/DesignCanvas.tsx
key_decisions:
  - Keyboard shortcuts use window-level keydown listener with activeElement tag guard to skip input/textarea/select
  - Ctrl+Shift+Z checked before Ctrl+Z to avoid false undo on redo shortcut
duration: ""
verification_result: passed
completed_at: 2026-03-26T05:41:35.166Z
blocker_discovered: false
---

# T04: Add canvas keyboard shortcuts (undo/redo/delete/select-all/deselect) and verify full integration — 71 tests pass, zero TypeScript errors

**Add canvas keyboard shortcuts (undo/redo/delete/select-all/deselect) and verify full integration — 71 tests pass, zero TypeScript errors**

## What Happened

Added a useEffect with window-level keydown listener to DesignCanvas.tsx implementing five keyboard shortcuts: Ctrl+Z (undo), Ctrl+Shift+Z/Ctrl+Y (redo), Delete/Backspace (remove selected), Escape (deselect all), Ctrl+A (select all). Handler guards against firing when an input/textarea/select element is focused. Unwrapped the _removeObject alias to removeObject for the delete handler. Both tsc and vitest pass cleanly — 71 tests across 6 files, zero TypeScript errors.

## Verification

npx tsc --noEmit: zero errors (exit 0). npx vitest run --reporter=verbose: 71 tests pass across 6 test files (exit 0).

## Verification Evidence

| # | Command | Exit Code | Verdict | Duration |
|---|---------|-----------|---------|----------|
| 1 | `cd app && npx tsc --noEmit` | 0 | ✅ pass | 2600ms |
| 2 | `cd app && npx vitest run --reporter=verbose` | 0 | ✅ pass | 2100ms |


## Deviations

None.

## Known Issues

None.

## Files Created/Modified

- `app/src/views/DesignCanvas.tsx`


## Deviations
None.

## Known Issues
None.
