FAILURE MAP
← Case archive

FA-8181 / Overlay interactions / Open access

Popover outside-interaction handling: A prevented event still dismisses an overlay · case 01

A prevented event still dismisses an overlay.

Verified by executionVariant 1 · 10 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The prevented operation uses `if prevented: return False` where the contract requires `if prevented: return opened`.

THE FAILURE

The prevented operation uses `if prevented: return False` where the contract requires `if prevented: return opened`.

Unsuccessful approach: Forcing open also changes a closed overlay on a cancelled event.

Case contract

Cancelled events preserve state; Escape closes; only pointerdown toggles triggers or dismisses outside; membership in the composed path recognizes descendants and portals.

Why this case matters

A deterministic model of popover outside-interaction handling; this isolates one interface invariant without requiring a browser.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(opened, target_path, trigger, panel, event, prevented):
    if prevented: return False
    if event == 'escape': return False
    if event != 'pointerdown': return opened
    if trigger in target_path: return not opened
    if panel in target_path: return opened
    return False
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('cancelled open', solve(True, ['outside'], 'trigger', 'panel', 'pointerdown', True), True)
check('cancelled closed', solve(False, ['outside'], 'trigger', 'panel', 'pointerdown', True), False)
check('escape open', solve(True, [], 'trigger', 'panel', 'escape', False), False)
check('escape closed', solve(False, [], 'trigger', 'panel', 'escape', False), False)
check('ignored', solve(True, [], 'trigger', 'panel', 'pointermove', False), True)
check('trigger opens', solve(False, ['icon','trigger'], 'trigger', 'panel', 'pointerdown', False), True)
check('trigger closes', solve(True, ['icon','trigger'], 'trigger', 'panel', 'pointerdown', False), False)
check('inside descendant', solve(True, ['button','panel'], 'trigger', 'panel', 'pointerdown', False), True)
check('parameterized descendant depth', solve(True, ['node'+str(i) for i in range(N)]+['panel'], 'trigger', 'panel', 'pointerdown', False), True)
for repetition in range(N):
    check('repeat inside descendant', solve(True, ['button','panel'], 'trigger', 'panel', 'pointerdown', False), True)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
cancelled openFalseTrueFailed
cancelled closedFalseFalsePassed
escape openFalseFalsePassed
escape closedFalseFalsePassed
ignoredTrueTruePassed
trigger opensTrueTruePassed
trigger closesFalseFalsePassed
inside descendantTrueTruePassed
parameterized descendant depthTrueTruePassed
repeat inside descendantTrueTruePassed

SHA-256 / ce97d3f75f13e4ec37ba71302427f9637064b080cc4f4287d2a71c9e97f410d3

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(opened, target_path, trigger, panel, event, prevented):
    if prevented: return True
    if event == 'escape': return False
    if event != 'pointerdown': return opened
    if trigger in target_path: return not opened
    if panel in target_path: return opened
    return False
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('cancelled open', solve(True, ['outside'], 'trigger', 'panel', 'pointerdown', True), True)
check('cancelled closed', solve(False, ['outside'], 'trigger', 'panel', 'pointerdown', True), False)
check('escape open', solve(True, [], 'trigger', 'panel', 'escape', False), False)
check('escape closed', solve(False, [], 'trigger', 'panel', 'escape', False), False)
check('ignored', solve(True, [], 'trigger', 'panel', 'pointermove', False), True)
check('trigger opens', solve(False, ['icon','trigger'], 'trigger', 'panel', 'pointerdown', False), True)
check('trigger closes', solve(True, ['icon','trigger'], 'trigger', 'panel', 'pointerdown', False), False)
check('inside descendant', solve(True, ['button','panel'], 'trigger', 'panel', 'pointerdown', False), True)
check('parameterized descendant depth', solve(True, ['node'+str(i) for i in range(N)]+['panel'], 'trigger', 'panel', 'pointerdown', False), True)
for repetition in range(N):
    check('repeat inside descendant', solve(True, ['button','panel'], 'trigger', 'panel', 'pointerdown', False), True)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
cancelled openTrueTruePassed
cancelled closedTrueFalseFailed
escape openFalseFalsePassed
escape closedFalseFalsePassed
ignoredTrueTruePassed
trigger opensTrueTruePassed
trigger closesFalseFalsePassed
inside descendantTrueTruePassed
parameterized descendant depthTrueTruePassed
repeat inside descendantTrueTruePassed

SHA-256 / b720c0d87c87a210b6b9c3f265412af408a955c93436c76f4b4ce6622b3d2d62

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 10 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Sign in to the archive ↗

Verification & scope

This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:38:19.304179+00:00.

Case digest / db3262b730b2bf06c10122c5487d58a2f8cd8025cf1b4fcfb0545bd54b883ccb