PR #32853 real dev verification, Linux, 2026-11-10
Main: 633438d54f17b99f73f1a09466ecbe4a6aa0d545 (github/main)
PR: 19beebfabb4a5b803d5204ac28d0439e728d4b4b (exact head)

Setup:
Separate main worktree, vp i in both checkouts, one background vp run dev at a time.
Isolated app state. Real git repository on a disposable 16 MiB tmpfs.
Project added through the app. Real Codex gpt-6.1-sol turns created/restored
report.txt, run.sh, tasks.md and an internal relative symlink.
Playwright from repo dependencies, /usr/bin/google-chrome.
No mocked filesystem, provider, server, or RPC handler.

Original failure, actual Files panel editor autosave:
Original: 4096 O bytes, sha256 957269f144778a4554482f666a89cbe723252ac16cf79c02fd0d5de9dd91dfa6
Fill the temporary filesystem, then free exactly 8192 bytes.
Click editor, Control+A, keyboard.insertText(65536 N characters).
Main: save reports ProjectWriteFileError; disk contains 12288 N bytes, 0 O bytes.
Main: original preserved = false.

Same actual Files panel editor autosave on PR:
Same original bytes and sha256, same 8192 bytes free, same 65536-byte replacement.
PR: save reports ProjectWriteFileError; disk contains 4096 O bytes, 0 N bytes.
PR: original preserved = true; .t3-save-* directories = [].
The editor retains the unsaved replacement draft, so disk inspection is the proof.

Authenticated projects.writeFile WebSocket RPC, running PR server:
Failed new-file save returned ProjectWriteFileError -> WorkspaceFileSystemOperationError
-> ENOSPC: no space left on device, write.
PASS: failed creation leaves no destination and no .t3-save-* directories.
After removing the filler:
PASS: successful new-file save writes exact contents.
PASS: successful executable overwrite writes exact contents and retains 0750.
PASS: internal symlink remains a relative symlink and updates resolved target.
PASS: .git/config write rejected; original config unchanged.
PASS: external symlink write rejected; outside sentinel unchanged.

Actual web UI neighboring behavior:
PASS: run.sh editor autosave writes #!/bin/sh\necho ui_verified\n and retains 0750.
PASS: rendered tasks.md checkbox check persists - [x] verify save to disk.
PASS: checkbox uncheck persists - [ ] verify save to disk.

Checks:
blacksmith-check run --id <task-owned-box> 'vp test run apps/server/src/workspace/WorkspaceFileSystem.test.ts'
33 tests passed, 1 test file passed.
Existing head CI: 31 successful, 0 failing, 0 pending.
No source changes or pushes needed.

Not verified:
Native Electron, iOS/Android clients; macOS/Windows filesystems; network filesystems;
quota-specific failures; process crash/power-loss durability; injected cleanup failure
in the running app (covered by the existing focused test instead).
No fsync durability claim.