Follow-up to 4376c5a6, found by a real BROWSER e2e (the flow the in-diff fix
missed). When the layout reshuffle's two halves land in SEPARATE sync cycles, the
later cycle's diff has only the DELETE of the old path — the matching add was
already pushed — so in-diff D+A coalescing can't see it, and the live page was
still trashed.
Robust fix on the identity invariant the reviewer (and the user) called out: a
page EXISTS iff its pageId is in the vault, regardless of filename. runPush now
collects the pageIds present at ANY path in the current `main` tree and passes
them to computePushActions; a deleted file whose pageId is still tracked
elsewhere is a MOVE, never a deletion. (Built only when the diff has deletes.)
Adds apps/server/test/git-sync-browser-e2e.cjs — a Playwright test that drives the
REAL Docmost web UI: log in, create several untitled pages, type a title, sync,
assert NOTHING is trashed. Reproduced the data loss before this fix; 5/5 green and
stable after. Engine suite 600 green (+2 computePushActions cases:
pageId-still-present -> skip; pageId-gone -> real delete).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
CRITICAL data-loss bug: creating pages in Docmost (which start UNTITLED) and then
typing a title could soft-delete OTHER pages. Untitled pages all serialize to the
`_` fallback filename; the layout disambiguates them (`_.md`, `_ ~slug.md`).
Retitling one frees the bare `_` and another untitled page's file relocates into
it. git's rename detection (`-M`) can't see the move (the tiny meta-only files are
too dissimilar), so `git diff` reports it as DELETE(old) + ADD/MODIFY(new). The
push took the DELETE literally and trashed a live page.
Root cause is that the push trusted git's path-level rename heuristic for page
IDENTITY. Identity is the pageId. Fix: before emitting any delete, coalesce by
pageId — a pageId that is BOTH deleted (pre-image) AND present on the surviving
side (current meta of an ADD or a MODIFY, since a relocation into an occupied path
shows as M) is one page that MOVED, classified as a rename/move and NEVER a delete.
Reproduced + verified on a live stand: 4 untitled pages + retitle one trashed a
different page before; after the fix, retitling one (and stress-retitling all)
trashes nothing. Engine suite 598 green; 3 new computePushActions cases (ghost
D+A move -> rename; real delete still deletes; unrelated D+A stay delete+update).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
