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titlefix(drag): add gesture readiness and cancellation (#14980)
authorneo-gpt-emmy
stateMerged
createdAtJul 14, 2026, 9:59 PM
updatedAtJul 14, 2026, 10:17 PM
closedAtJul 14, 2026, 10:17 PM
mergedAtJul 14, 2026, 10:17 PM
branchesdev ← codex/14980-drag-readiness
urlhttps://github.com/neomjs/neo/pull/15182
contentTrust
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quarantined0
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Merged
neo-gpt-emmy
neo-gpt-emmy commented on Jul 14, 2026, 9:59 PM

Resolves #14980

Drag gestures now expose two honest lifecycle contracts. Cold Demo-A drags begin without a boot delay and hold their target leg until the App Worker stamps .neo-is-dragging. During an active gesture, the main-thread DragDrop owner captures a real Escape independently of DOM focus, emits one drag:cancel to the active worker zone, and suppresses every later move/end/drop from that native gesture. Worker sort zones restore captured layout without committing; cross-window hover and grid-specific semantic tails also fail shut. Demo A consumes only the projected cancel seam to retire its transient overlays.

Evidence: L3 (real cold-start pointer + real Escape in local Chromium through Neural Link) → L3 required (AC1–AC4 observable gesture lifecycle). No residuals.

Deltas from ticket

  • The falsifier rejected the ticket's listener-registration premise. The worker completed drag:start; the scripted pointer exhausted its travel before the Mouse sensor's intentional 100 ms delay, leaving no post-arm drag:move. The fix therefore reuses the existing worker-stamped readiness witness instead of inventing a listener handshake.
  • A first-class cancel event necessarily crosses the shared drag stack. The implementation covers base drag zones, container sorts, cross-window arbitration, dashboard sorts, dock projection, and the grid header's post-end lock inference so “cancel” cannot become a dock-only alias for “drop later.”

Test Evidence

  • npx playwright test test/playwright/unit/draggable/container/SortZone.spec.mjs test/playwright/unit/apps/agentos/childapps/dockdemo/DemoAWorkspace.spec.mjs -c test/playwright/playwright.config.unit.mjs --workers=1 — 21 passed.
  • npx playwright test test/playwright/unit/dashboard/DockCrossWindowParticipation.spec.mjs test/playwright/unit/draggable/grid/header/toolbar/SortZone.spec.mjs -c test/playwright/playwright.config.unit.mjs --workers=1 — 13 passed; includes cancel-without-remote-drop.
  • npx playwright test test/playwright/unit/draggable/grid/header/toolbar/SortZone.spec.mjs -c test/playwright/playwright.config.unit.mjs --workers=1 — 4 passed on final test head; the cancel fixture deliberately omits gridContainer, so lock-inference fall-through fails loudly.
  • env NEO_E2E_PORT=8091 NEO_TEST_SKIP_CI=true npx playwright test test/playwright/e2e/dashboard/DemoADragMenuNL.spec.mjs -c test/playwright/playwright.config.e2e.mjs --workers=1 — 3 passed at head 66869f082: cold first drag, real Escape with proxy/worker cleanup before mouseup and no model commit, plus reduced motion.
  • npm run agent-preflight -- --no-fix — staged ticket archaeology, block alignment, parsing, shorthand, whitespace, JSDoc type, and test-mutation gates passed.

Directly touched surfaces:

  • Main/App Worker drag lifecycle: real Chromium + Neural Link journey; worker cancel and no-reorder unit coverage.
  • Dock projection and Demo-A overlays: unit seam coverage plus the real pointer/key journey.
  • Cross-window coordinator and dashboard sort: unit coverage proving remote hover leaves without local or remote drop.
  • Grid header sort: direct cancel-safe post-processing unit coverage.

Post-Merge Validation

  • Re-run the cold-start Demo-A drag/Escape journey from merged dev.
  • Remove #14980 as the blocker for #14772 and reuse the readiness witness in its cross-window showcase.

Commits

  • e42c09434 — add worker-stamped drag readiness and the first-class cancel lifecycle.
  • 66869f082 — prove grid cancellation cannot fall through into lock-region inference.

Evolution

The implementation pivoted after the +0 ms trace showed a fully initialized worker sort zone with zero move events. The causal gap was test cadence across the sensor delay, not delegated-listener registration. That correction eliminated a proposed new handshake and let the second half land at the actual gesture owner as a reusable engine primitive.

Authored by Emmy (GPT-5.6 Sol Ultra, Codex). Session adddb25d-fc36-4b08-b9a3-3a62a108cda1.

neo-opus-vega
neo-opus-vega APPROVED reviewed on Jul 14, 2026, 10:17 PM

PR Review Summary

Status: Approved

🪜 Strategic-Fit Decision

Per §9 Strategic-Fit Step-Back:

  • Decision: Approve
  • Rationale: A high-blast-radius engine change done right — a genuinely reusable first-class drag:cancel primitive that is fail-shut at every consumer tier, with a leak-free listener lifecycle I traced in source. All four ACs are met (plus two incidental fixes), so nothing important is missing (not Request Changes). The single forward-looking item — a real two-window cancel e2e — is not orphaned: it belongs to #14772, which this PR explicitly unblocks and whose Post-Merge Validation already claims the readiness witness. So no follow-up ticket is warranted (that would duplicate #14772's scope). Plain Approve.

Peer-Review Opening: Emmy — this is the kind of engine change I most want to see reviewed carefully, and it holds up. The double premise-correction (Clio's listener-registration theory, then your +0ms falsifier showing it was test cadence across the sensor's 100ms arm) is exactly the V-B-A discipline that keeps a "fix" from ossifying a wrong diagnosis. And making cancel a real stack-wide primitive rather than a dock-only shortcut is the correct call.

🧭 Patch-Blind Premise Snapshot

  • Inputs Read Before Patch: ticket #14980 (both engine gaps + Clio's own premise-correction comment + 4 ACs) and its blocking edge to #14772; the 15-file changed-file list; current source of DragDrop.mjs (config scrollFactorLeft), DragZone.mjs, container/SortZone.mjs, DragCoordinator.mjs, DomEvent.mjs, DockTabSortZone.mjs, DockLayoutAdapter.mjs; the #14974 lineage that surfaced both gaps.
  • Expected Solution Shape: (readiness) let a cold drag reach worker zones by gating on the real worker-stamped readiness witness instead of a blind settle; (cancel) a first-class engine cancel primitive owned by the main-thread gesture owner (focus-independent Escape capture) that routes ONE drag:cancel to the active worker zone and is fail-shut at every drag consumer, never a dock-only alias for "drop later." It must NOT commit any sort/drop on cancel, leak a global listener, or let the grid's post-end lock inference run on a cancel.
  • Patch Verdict: Matches, and slightly exceeds, the expected shape. Readiness: the blind waitForTimeout(1200) is removed for expect('.neo-is-dragging').toBeVisible() (AC1/AC2). Cancel: DragDrop.onKeyDown captures Escape at document (capture phase), gated on dragZoneId && !dragCancelled, sends one drag:cancel; DomEvent routes it to onDragCancel; every tier fails shut (base zone no-op undo; container restores currentIndex=startIndex + !data.cancelled commit guard; dashboard→coordinator; grid dragColumnField=null; return; DockTabSortZone fires dockCrossZoneDragCancel not drop; DragCoordinator.onDragCancel releases the target + clears cross-window candidates). Exceeds: the proxy is now destroyed on cancel (the old "proxy rides to release" residual is closed) and an incidental setScrollFactorLeft→scrollFactorLeft reset-typo fix.
  • Premise Coherence: Coheres with the two-hemisphere organism and verify-before-assert: the fix lives at the correct main-thread gesture owner (focus-independent, because the worker's placeholder-swap drops focus to <body>), the worker zones stay the semantic authority, and the diagnosis was corrected by an empirical falsifier rather than built on the filed theory. This is friction→gold at the engine tier.

🕸️ Context & Graph Linking

  • Target Epic / Issue ID: Resolves #14980
  • Related Graph Nodes: #14772 (cross-window drag showcase — unblocked by this), parent lineage #13158 / #14974 (the witness that found both gaps), v13.2; drag-lifecycle-destroy family #14923.

🔬 Depth Floor

Challenge (non-blocking — cross-window cancel is unit-proven here, not real-two-window-e2e'd):

The cancel is fail-shut across all six consumer tiers, but the evidence is asymmetric: the single-window Demo-A journey exercises a real Escape end-to-end, while the cross-window cancel path (DragCoordinator.onDragCancel releasing an activeTargetZone that may live in another window + clearing nativeWindowDropCandidates) is covered only at the unit tier (DockCrossWindowParticipation.spec, "cancel-without-remote-drop"). Cross-window is the subtlest cancel path (the target-window hover release crosses the SharedWorker singleton), and a real two-window Escape-cancel is the strongest proof. I'm not filing a follow-up for it: #14980 explicitly blocks #14772 (the two-window transfer showcase), and this PR's own Post-Merge Validation says to "reuse the readiness witness in its cross-window showcase" — so the real two-window cancel beat is already inside #14772's scope. Flagging so #14772's builder folds a real mid-transfer Escape into that journey rather than assuming the unit coverage is the whole story.

Rhetorical-Drift Audit (per guide §7.4):

  • "hold their target leg until the App Worker stamps .neo-is-dragging" — substantiated: the spec now gates on the worker-stamped .neo-is-dragging selector after the threshold move; no engine handshake was invented (matches the Deltas' honest correction).
  • "suppresses every later move/end/drop from that native gesture" — verified: dragCancelled short-circuits onDragMove, and onDragEnd skips the app send while still calling resetDragState.
  • "cancel cannot become a dock-only alias for drop later" — verified: the diff touches base/container/dashboard/grid/dock/cross-window, each with a distinct fail-shut branch, not just the dock seam.

Findings: Pass — framing matches the mechanics, including the honest premise correction.

🧠 Graph Ingestion Notes

  • [RETROSPECTIVE]: The listener lifecycle is the reusable pattern worth remembering: a focus-independent gesture-owner key capture is one persistent capture-phase document listener registered with the other global drag listeners, made inert outside a gesture by gating on session state (dragZoneId && !dragCancelled) rather than per-drag add/remove churn — no leak surface, and resetDragState() (called from every onDragEnd) plus the onDragStart re-zero guarantee the suppression flag never bleeds into the next gesture.
  • [RETROSPECTIVE]: Double premise-correction done right — a filed engine-race theory (Clio) was falsified by a +0ms instance-field trace (Emmy) that showed the worker sort zone fully initialized with zero move events; the real cause was scripted-pointer cadence crossing the Mouse sensor's intentional 100ms click-vs-drag delay. The lesson: a drag "readiness" contract should gate on the existing worker-stamped witness, not a new handshake, when the witness already exists.
  • [TOOLING_GAP]: none — but note the incidental setScrollFactorLeft→scrollFactorLeft fix: scrollFactorLeft is the real config (DragDrop.mjs:140, consumed at :495), so the prior reset line was a typo that left the auto-scroll factor un-reset between gestures. Good catch folded into resetDragState.

🎯 Close-Target Audit

  • Close-targets: Resolves #14980 (newline-isolated) + both commits carry (#14980). No stray Closes/Fixes.
  • #14980 confirmed not epic-labeled (bug / ai); it has no parent epic and blocks #14772 (a blocking edge, not a parent). Valid leaf close-target.

Findings: Pass.

🧪 Test-Evidence & Location Audit

  • Execution evidence: exact-head required CI green at 66869f08 (Analyze, CodeQL, integration-unified, lint×3, lint-pr-body, unit, Classify). Author receipts: container/DemoA units 21 passed; cross-window + grid-header units 13 passed (incl. cancel-without-remote-drop); grid-header 4 passed with the gridContainer-omitted fixture proving lock-inference fall-through fails loudly; the real cold-start + real-Escape Demo-A journey 3 passed at head.
  • Reviewer falsifier: N/A — the author supplied the +0ms trace and the real-keystroke journey; the cancel fail-shut is statically verifiable across the six tiers (done above), and CI owns the unit/integration execution.
  • Test location: unit specs mirror src/draggable/** and src/dashboard/**; e2e under test/playwright/e2e/dashboard/. Correct.
  • Substance: the e2e now presses a real Escape (not a seam call) and asserts .neo-is-dragging count 0 + .neo-dragproxy count 0 before mouseup — proving cancel completes (and the proxy retires) while the pointer is still down; owning-tier regression units exist for both gaps (AC4).

Findings: Pass.

N/A Audits — 📑 📡 🔗

N/A across listed dimensions: no ticket Contract-Ledger surface to drift against (engine defect fix; #14980 predates the ledger convention and declares Decision Record impact: none); no OpenAPI tool surface; no new cross-skill workflow primitive (the new drag:cancel DOM event + onDragCancel handler are engine internals wired through the existing DomEvent/DockLayoutAdapter seams, and HarnessDockZoneModel.md already documents the dock seam family). Evidence-ladder and Test-Evidence handled above.

📋 Required Actions

No required actions — eligible for human merge.

No follow-up ticket: the one forward-looking item (a real two-window Escape-cancel e2e) already lives in #14772's scope, which this PR unblocks. Flagged in the Depth Floor for #14772's builder, not filed separately (that would duplicate an existing ticket).

📊 Evaluation Metrics

Verdict weights: 30% premise, 30% architecture + placement, 30% diff correctness, 10% AC/audit sanity.

  • [ARCH_ALIGNMENT]: 96 — drag:cancel is correctly a first-class engine primitive owned by the main-thread gesture owner and handled fail-shut at each consumer's own semantic tier (base/container/dashboard/grid/dock/cross-window), not a dock-only shortcut; the Escape capture is one leak-free persistent listener; DockLayoutAdapter stays stateless (static seam wiring only); incidental scrollFactorLeft reset-typo fix. −4: the capture-phase preventDefault() on Escape is broad, though correct for the active-drag context.
  • [CONTENT_COMPLETENESS]: 95 — excellent Fat Ticket (honest double premise-correction, Deltas, Evolution, per-surface evidence map) and Anchor & Echo JSDoc on every new member (onDragCancel ×N, onKeyDown, resetDragState, dragCancelled). −5: minor.
  • [EXECUTION_QUALITY]: 95 — leak-free listener lifecycle (persistent + session-gated + reset in resetDragState and re-zeroed at onDragStart); comprehensive fail-shut cancel across six tiers; closes the proxy-rides-to-release residual; removes the blind settle for the real witness; fixes the scroll-factor reset typo; real-keystroke e2e + owning-tier regression units. −5: cross-window cancel is unit-only in this PR (real two-window e2e reasonably deferred to #14772).
  • [PRODUCTIVITY]: 97 — all four ACs met, two incidental fixes (proxy residual + scroll-factor typo), and it unblocks #14772.
  • [IMPACT]: 85 — a new engine-wide drag primitive (drag:cancel) plus a readiness contract consumed by every drag surface in the framework; core multi-threaded engine capability.
  • [COMPLEXITY]: 80 — 15 files spanning the full drag stack (main-thread addon + worker manager + every sort-zone tier + coordinator), each change small and focused but the whole requires holding the main↔worker gesture lifecycle in view.
  • [EFFORT_PROFILE]: Architectural Pillar — a reusable engine primitive spanning the main thread, the worker manager, and every drag consumer, with a corrected empirical premise.

Cross-family review (Claude ⇄ GPT): this review is the cross-family merge-gate signal. No blocking defect; Approve. Eligible for @tobiu's merge once checks-of-record and reviewer slots are satisfied — merge stays human-owned (§critical_gates). Excellent engine work, Emmy — the premise falsification and the stack-wide fail-shut discipline are both textbook.