Modifiers were sampled only inside resolveOperation, reached from
dropUpdated and the commit — and drop callbacks arrive only while the
mouse moves, so ⌥ pressed against a still pointer changed nothing
until the next twitch. DragSession now arms a local .flagsChanged
watch for exactly the session's lifetime (begin arms, end stops, the
watchdog guarantees end; ⇧/⌃/caps don't count, a settled hold
swallows) and publishes modifierGeneration; the three retargets record
which window's surface resolved the proposal (RetargetOrigin — weak
registry identity, never board root, so cross-board and two-windows-
one-board both answer correctly), and the hovered window replays that
same retarget with the operation re-resolved FIRST, since the index
space is a function of it. The monitor is injectable — the real one
needs a live event stream no test bundle has.
Drag-perf card d491e7d3.
Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97
DragAutoScroller.run() consumes an AsyncStream of CADisplayLink
targetTimestamps from NSView.displayLink(target:selector:) on the
lane's existing anchor view (which was already the right NSView — no
new plumbing). The stream is the lifetime: cancellation ends the
iteration, termination invalidates the link, the link releases its
target. DragAutoScrollClock keeps the retired loop's two non-trivial
rules — first tick scrolls nothing, no tick integrates past 50ms (a
paused link resumes with the whole gap as its delta) — and the math is
frame-rate independent by test: one second at the edge moves 800.0
points at 120Hz and at 60Hz alike. Run-loop mode .common is
load-bearing: a drag runs AppKit's event-tracking mode.
Drag-perf card 2e08fd31.
Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97
LaneWidthHold: after the release the session's frozen standard and the
WRITTEN unit count keep governing the strip until a landed snapshot
carries that width back — dividing the already-grown window by the
stale unit total in between was the visible two-step. A deliberately
separate type from CommittedHold: that hold stands in for an
arrangement and any landing retires it; this one stands in for a value
and only a landing that carries it will do. Echo reads through
LaneLayoutMath.displayUnits so the width-1 key-removal case compares
right; the watch rides landedReloads so a value-equal echo still
answers; width writes now return whether bytes reached disk so a
refused or no-op write dissolves the hold instead of arming it; the
1500ms timeout family covers the rest.
Drag-perf card 231e3693.
Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97
The modifier flip (⌥ copy / ⌘ move) now reflows the source board once:
a copy re-admits the dragged originals into the resting layout, standing
dimmed in place, and a move lifts them out as before. This retires
DRAG-REORDER.md's operation-blind carve-out and makes 04-interactions.md's
"originals stay" true in flight, not just at echo. The one seam is
DragSession.hiddenMembers reading the observed operation.
Consequences carried honestly: copyCards now takes its index in the
lane's full rendered space (the zones counted the originals, so the
geometry's number is the writer's number — the old neighbour remap is
deleted); resolveOperation freezes under the committed hold exactly as
propose does, fixing a real bug where a settled within-board ⌥-copy drew
the move arrangement until the echo and visibly re-shuffled. Stationary
flips still wait for the next dropUpdated (their own Backlog card).
Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97
The second half: system drag sessions over phase 1's model, per
DRAG-REORDER.md and 04-interactions.md § Drag & drop.
- Card faces, lane headers, and trash rows drag as NSItemProvider sessions
(two exported UTTypes, JSON payload in flatten order, plain-text titles as
the secondary representation) — replacing m4's custom lane-reorder gesture
and trash drag-out wholesale; the app-wide DragSession carries the members,
the frozen dragged sizes, the live proposal, and the effective operation.
- Three drop delegates (lane masonry, strip, window fallback), each accepting
both types and routing internally per the single-target-dispatch rule; the
cursor is the physical mouse converted to strip space; proposals come from
DropSlotMath with hysteresis threaded through, and the lane-strip proposal
clamps in front of the shown trash.
- Locality picks the default — move within a board, copy across, the badge
tracking live; ⌥ forces copy (ignored on within-board lane drags), ⌘
forces move; trash rows restore within their board (positional), copy out
across boards by default, ⌘ forcing the true restore-move.
- N contiguous shadows with reflow keyed on the proposal; the
committed-overlay hold renders the dropped arrangement until the reload
echo lands (1.5 s dissolution deadline for refused writes); the
re-grounding trio: geometry re-derives per render, proposals re-validate
by liveness at release, an emptied drag cancels itself.
- Edge autoscroll (ticking driver over DragAutoScrollMath, re-targeting per
step), the mouse-up-gated late-event cleanup, and the polling watchdog —
the pathfinder's lifecycle traps, ported.
- Store: moveLanes and multi-card restoreByDrag join the one-bracket drop
commits.
784 unit tests.
Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY
The pathfinder's drag-reorder model, ported and generalized (DRAG-REORDER.md
travels with it, rewritten for lanes, the interior masonry, multi-drag,
cross-board sessions, the re-grounding trio, and the committed-overlay hold):
- DropSlotMath — resting-layout zones from analytic lane arithmetic and the
pure masonry placement (MasonryLayout now lays out through the same
MasonryPlacement the drag reads, so geometry cannot drift), span-capped
triggers sized to the dragged run's future footprint, hysteresis holds with
the fresh-entry fallback, boundary ties, own-slot no-ops; nil means hold.
- DragAutoScrollMath — the activation bands and velocity ramp, pure.
- The drop commits, one performWrite bracket each: moveCards/copyCards within
a board (insertion ranks touch only the dragged cards; renumber fallback);
receiveCards/receiveLanes/receiveRestoredCards on the destination store for
cross-board copy and ⌘-move with the import-boundary remint, lane copies
stripping tombstoned cards while moves carry them; restoreByDrag is now
positional, writing order only when the drop names a new one.
Gestures, sessions, previews, and delegates are the second half.
773 unit tests (87 new since the keyboard grammar).
Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY
rzen