Bug: quickfiler-dropdown-796-post-merge-review-residuals

[drmoisan]

• Work Mode: minor-audit

Summary

PR #807 (issue #796, folder drop-down closes on open and click does not select) merged with four non-blocking review findings and one untested seam in the same three files. The most consequential is CR-3: the new AC2 self-inflicted-deactivation guard in QfcFormController.ParkFocusAndCancelSelectors also gates the #791 Cancel teardown caller, where its predicate has no meaning, so the teardown's synchronous selector-cancel stage is skipped whenever a breadcrumb popup is open and the popup is only closed later by a fire-and-forget reset. The others are a commit-pending latch that is never cleared on consumption (CR-2), a stale comment that now contradicts the guard placement (CR-1), a dead internal accessor (CR-4), and no automated test on the AC2 producer side (CR-7). Source: code-review.2026-09-07T17-05.md in the #796 feature folder and the Follow-ups section of PR #807.

Environment

• OS/version: Windows 11 Pro 10.0.26200
• Runtime: .NET Framework 4.8 VSTO Outlook add-in; main at 04a54e68 (PR fix(796): keep the QuickFiler folder drop-down open and commit row selection before cancel #807 merge commit)
• Command/flags used: QuickFiler ribbon launch; Cancel (Bug: quickfiler-high-confidence-cancel-teardown-and-deadline-defects #791 ordered teardown) with a breadcrumb popup open
• Data source or fixture: live mailbox; code-read findings, no runtime capture yet

Steps to Reproduce

1. Launch QuickFiler and open the folder drop-down on any item so a ToolStripDropDown popup is open.
2. Trigger Cancel (the Bug: quickfiler-high-confidence-cancel-teardown-and-deadline-defects #791 ordered teardown) while the popup is open.
3. Observe that the park-focus teardown stage skips every selector cancel because the AC2 guard treats the open popup as a self-inflicted deactivation, and that the popup is closed only later by ResetBreadcrumb via a posted, fire-and-forget reset.
4. For CR-2: open the popup, commit a selection (sets the commit-pending latch), then cause the next open to throw before ShowPopup runs; RestoreAfterOpenFailure calls FinishClose(Uncommitted) and the stale latch suppresses the cancel, leaving a selector session open with no popup.

Expected Behavior

• The AC2 guard applies only to the Form.Deactivate caller; the Cancel teardown's park-focus stage cancels every open selector synchronously as the Bug: quickfiler-high-confidence-cancel-teardown-and-deadline-defects #791 ordering requires.
• The commit-pending latch lives for exactly one popup lifetime on every path, including open failure.
• Comments in BreadcrumbDropDownHost.FinishClose describe the two independent gates accurately.
• No dead accessor remains, and the AC2 producer side has an automated test.

Actual Behavior

• QfcFormController.Deactivate.cs line 118 gates both callers of ParkFocusAndCancelSelectors; from ActionCancelAsync stage park-focus (QfcFormController.EventHandlers.cs line 144) the predicate degenerates to "is any popup open?" and the stage is skipped. Mitigation exists later via QfcCollectionController.Cleanup -> QfcItemController.Cleanup -> ItemViewer.ResetBreadcrumb -> BreadcrumbDropDownOpenCoordinator.Reset, but through PostAsync, so the ordering guarantee the teardown was written to provide is weakened.
• IsCommitPending (BreadcrumbDropDownHost.Open.cs 102-107) is cleared only by ShowPopup; RestoreAfterOpenFailure (BreadcrumbDropDownHost.cs line 455) calls FinishClose(Uncommitted) unconditionally and can consume a previous lifetime's latch.
• BreadcrumbDropDownHost.cs line 450 still says "only the focus step is gated; the cancel step above always runs", contradicted by the gate at line 447.
• QfcItemController.EventHandlers.cs line 209 SearchOwnsDropDownDismissal has no reader (the underlying field is the live AC4 latch).

Logs / Screenshots

• Attached minimal logs or screenshot
• Snippet: none; findings are from the merged code review. The AC6 close-ordering observation that motivated the guard is in evidence/other/ of the Bug: quickfiler-folder-dropdown-closes-on-open-and-click-does-not-select #796 feature folder (2026-09-07T12-19).

Impact / Severity

• Blocker
• High
• Medium
• Low

CR-3 is rated Major/latent by the reviewer: the class documentation states that no breadcrumb popup may stay open after teardown or WinForms modal menu mode keeps redirecting keyboard messages to the popup, which is the #677 keyboard-lock class. The remaining items are minor but sit in the same files and should ship together.

Source

From: docs/features/potential/2026-09-07-quickfiler-dropdown-796-post-merge-review-residuals.md

[drmoisan]

Consolidated into #810 on 2026-09-07 (maintainer decision: batch review residuals by blast radius). All acceptance criteria from this issue are carried in #810; this issue is closed as superseded, not as fixed.