Add MacTree, a WizTree-style disk space analyzer for macOS

[aodjo]

Native macOS 15+ app (Swift / AppKit) that shows what is using disk space, in the style of WizTree.

What's in it

• Scanner: parallel getattrlistbulk(2) on 16 threads. On an M-series Mac it scanned about 6.7 M items (the whole boot disk) in about 25 s, and 1.2 M items (/Applications) in about 3 s. Totals match du to within 0.1 %. It counts APFS firmlinks once, stays inside the root's APFS container, skips other disks, network and autofs mounts, and never downloads iCloud "dataless" files.
• Tree View: WizTree's columns (% of Parent bar, Size, Allocated, Items, Files, Folders, Modified).
• File View: every file sorted by size. Search takes substrings or wildcards, and ; or | combine terms.
• File types: per-extension totals, coloured like the treemap. Select a type to highlight it, or double-click to list its files.
• Treemap: cushion shading and continuous zoom around the pointer (wheel or pinch, up to 10,000×). Drag pans; double-click opens a folder on its own.
• Deletion:
  • Delete marks the selection with a red border in every pane.
  • Toolbar Delete Permanently, left of the search field, removes the marked items after one confirmation. Cancel is the default button.
  • Move to Trash (⌘⌫) stays available.
• Other: Size / Allocated toggle (allocated by default), Quick Look, Rescan This Folder, and CSV export (also headless: MacTree --export / out.csv).
• Full Disk Access: a sheet at launch explains the permission and has a draggable app icon. It detects the grant from a fresh child process and offers a relaunch. System Settings' "Quit & Reopen" works while the sheet is open.
• English / Korean UI.

Build

./scripts/build-app.sh produces build/MacTree.app. The script generates the icon and signs with the first "Apple Development" identity if one is present, otherwise ad-hoc. SIGN_IDENTITY overrides the choice.

CI

.github/workflows/build.yml:

• On pull requests and pushes to main, builds on macos-15 with the latest stable Xcode.
• Runs a scan as a smoke test, verifies the code signature, and uploads MacTree.zip.
• On v* tags, also publishes a GitHub release with the zip.

Notes

• Every function, method and constant has an English JSDoc-style doc comment.
• Some UI tests were done headlessly (window snapshots, simulated zoom steps, marking and deleting in a scratch folder). Real mouse, trackpad and drag interaction was not exercised.

https://claude.ai/code/session_0115d7b3mfRT6Gs8mgqtAt1x

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.