Framing: docs/desktop-save-framing.md (Q#DS1-10). Save the open file
buffers, window layout, and per-window positions on quit; rebuild them
on startup. Emacs desktop.el, opt-in, local-mode only in v1.
All-Rust (Q#DS1) --- the core window enums are not serde and there is
no Lua tree API, so the layout mirror + structural rebuild live in Rust.
Lua adds only the opt-in switch and manual commands.
src/desktop.rs (new):
- Serde mirror (SavedDesktop / SavedBuffer / SavedNode / SavedLeaf /
SavedOrientation): every open file buffer (visible OR hidden, so a
switched-away file survives), the layout tree with orientation +
weights + nesting, per-leaf cursor/view_top, and an active-leaf
preorder index with a nearest-neighbor fallback (Q#DS10).
- session_key: SHA-256, name.<hex> when a socket name is set else
cwd.<hex> (charset-safe for the pmacs.state key).
- save_session / restore_session take the &Lua that carries the
SharedCore / StateDir / LocalInstanceInfo app-data, so they run
identically from a pmacs.session.* binding and the startup trigger.
- restore ordering (Q#DS3): open all buffers; prune EVERY window of the
old LOCAL layout (not just scratch); rebuild the tree; then per leaf
in preorder activate its window and fire buffer.after-load once per
newly-loaded buffer (hooks read active state), and write the exact
cursor/view_top AFTER so desktop wins over saveplace (same file in two
panes keeps distinct positions). A missing file collapses its leaf.
src/editor_core.rs: get_or_load_buffer(path) --- find_by_path else
load fresh, WITHOUT switching the active window; returns (id, newly).
src/lua_bindings: pmacs.session.{save_desktop, restore_desktop,
arm_restore, is_daemon}; DesktopRestoreArmed + DaemonMode markers;
fire_after_load_hook seam.
builtin/runtime/desktop.lua: pmacs.session.desktop_mode(on) wires
before-quit save + arms restore; desktop-save / desktop-restore
commands. No-op under a daemon (Q#DS9).
Startup trigger (Q#DS7): editor::run captures had_file before the match
consumes `file`, and restore_desktop_if_armed runs INSIDE the RunLocal
arm (after attach dispatch) so a hand-off to attach never populates an
EditorState it is about to drop. Daemon marks DaemonMode → desktop
stays local-only.
Tests: src/desktop.rs units (tree collapse, active-leaf fallback,
key/json round-trip) + tests/desktop_acceptance.rs (9): nested weighted
round-trip, hidden-buffer survival, after-load-active probe, same-file
two-pane distinct positions, missing-file collapse + focus fallback, no
orphan windows, name-vs-cwd key scoping, modified warning, startup gate.
Gates: fmt + workspace clippy clean; lib 1487; crdt 1658; desktop 9;
persistence 5; m4 90; m8 daemon 10/15; query-replace/completion/
listview/overlay/cua green; GPU 58; git diff --check clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Levi Neuwirth
3607df0afe