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FA-35231 / Notification interfaces / Open access

Notification burst summary interaction: close-before-mount from expanding-details · case 01

The close-before-mount event leaves a notification in summary-visible instead of closing-details.

Verified by executionVariant 1 · 38 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Closing forgets an outstanding detail mount.

VERIFIED REPAIR

Commit the expanding-details / close-before-mount transition to closing-details; preserve the other explicitly stipulated transitions.

Unsuccessful approach: Showing details despite close reverses the latest intent.

Case contract

Notification burst summary interaction is a bounded visual-notification workflow with mutable policy state {'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3}. Its default transition relation is {('individuals-visible', 'burst-detected'): 'condensing', ('condensing', 'summary-mounted'): 'summary-visible', ('condensing', 'summary-mount-failed'): 'individuals-visible', ('summary-visible', 'inspect-burst'): 'expanding-details', ('expanding-details', 'details-mounted'): 'details-visible', ('details-visible', 'collapse-details'): 'summary-visible', ('summary-visible', 'new-burst-item'): 'summary-updating', ('summary-updating', 'summary-update-mounted'): 'summary-visible', ('expanding-details', 'close-before-mount'): 'closing-details', ('closing-details', 'late-details-mounted'): 'summary-visible'}; domain inputs can suppress or redirect transitions and update policy fields, as specified in solve. Different-generation events are inert. Batches apply in order. Optional observe returns the selected policy field alongside the phase.

Why this case matters

Visual notification lifecycle ordering can leave an inbox or toast showing the wrong actionable state even when transport succeeds.

1 / The failure

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

N = 1
observations = []
def solve(initial, events, generation, payload=None, observe=None):
    table = {('individuals-visible', 'burst-detected'): 'condensing', ('condensing', 'summary-mounted'): 'summary-visible', ('condensing', 'summary-mount-failed'): 'individuals-visible', ('summary-visible', 'inspect-burst'): 'expanding-details', ('expanding-details', 'details-mounted'): 'details-visible', ('details-visible', 'collapse-details'): 'summary-visible', ('summary-visible', 'new-burst-item'): 'summary-updating', ('summary-updating', 'summary-update-mounted'): 'summary-visible', ('expanding-details', 'close-before-mount'): 'summary-visible', ('closing-details', 'late-details-mounted'): 'summary-visible'}
    data = json.loads(json.dumps({'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3})) if payload is None else {**json.loads(json.dumps({'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3})), **json.loads(json.dumps(payload))}
    state = initial
    for delivery in events:
        event, event_generation = delivery[:2]
        arg = delivery[2] if len(delivery) > 2 else {}
        if event_generation == generation:
            previous = state
            if event in ('summary-mounted','details-mounted','late-details-mounted','summary-update-mounted') and arg.get('mount',data['mount']) != data['mount']: event = 'unknown-event'
            if event == 'new-burst-item' and arg.get('item','c') not in data['items']: data['items'].append(arg.get('item','c'))
            state = table.get((state, event), state)
            if state == 'summary-visible':
                data['summary_members'] = data['items'][:]
                data['detail_members'] = []
            if state == 'details-visible': data['detail_members'] = data['items'][:]
            if state == 'empty': data['summary_members'] = []; data['detail_members'] = []
    return {'phase': state, 'value': data[observe]} if observe else state
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('individuals-visible / burst-detected', solve('individuals-visible', [('burst-detected', N)], N), 'condensing')
check('condensing / summary-mounted', solve('condensing', [('summary-mounted', N)], N), 'summary-visible')
check('condensing / summary-mount-failed', solve('condensing', [('summary-mount-failed', N)], N), 'individuals-visible')
check('summary-visible / inspect-burst', solve('summary-visible', [('inspect-burst', N)], N), 'expanding-details')
check('expanding-details / details-mounted', solve('expanding-details', [('details-mounted', N)], N), 'details-visible')
check('details-visible / collapse-details', solve('details-visible', [('collapse-details', N)], N), 'summary-visible')
check('summary-visible / new-burst-item', solve('summary-visible', [('new-burst-item', N)], N), 'summary-updating')
check('summary-updating / summary-update-mounted', solve('summary-updating', [('summary-update-mounted', N)], N), 'summary-visible')
check('expanding-details / close-before-mount', solve('expanding-details', [('close-before-mount', N)], N), 'closing-details')
check('closing-details / late-details-mounted', solve('closing-details', [('late-details-mounted', N)], N), 'summary-visible')
check('older notification incarnation', solve('individuals-visible', [('burst-detected', N - 1)], N), 'individuals-visible')
check('future notification incarnation', solve('individuals-visible', [('burst-detected', N + 1)], N), 'individuals-visible')
check('unknown event is inert', solve('individuals-visible', [('unknown-event', N)], N), 'individuals-visible')
check('empty delivery batch', solve('individuals-visible', [], N), 'individuals-visible')
check('N stale deliveries before current delivery', solve('individuals-visible', [('burst-detected', N - 1)] * N + [('burst-detected', N)], N), 'condensing')
check('trace burst-detected then summary-mounted', solve('individuals-visible', [('burst-detected', N), ('summary-mounted', N)], N), 'summary-visible')
check('trace burst-detected then summary-mount-failed', solve('individuals-visible', [('burst-detected', N), ('summary-mount-failed', N)], N), 'individuals-visible')
check('trace summary-mounted then inspect-burst', solve('condensing', [('summary-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace summary-mounted then new-burst-item', solve('condensing', [('summary-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace summary-mount-failed then burst-detected', solve('condensing', [('summary-mount-failed', N), ('burst-detected', N)], N), 'condensing')
check('trace inspect-burst then details-mounted', solve('summary-visible', [('inspect-burst', N), ('details-mounted', N)], N), 'details-visible')
check('trace inspect-burst then close-before-mount', solve('summary-visible', [('inspect-burst', N), ('close-before-mount', N)], N), 'closing-details')
check('trace details-mounted then collapse-details', solve('expanding-details', [('details-mounted', N), ('collapse-details', N)], N), 'summary-visible')
check('trace collapse-details then inspect-burst', solve('details-visible', [('collapse-details', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace collapse-details then new-burst-item', solve('details-visible', [('collapse-details', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace new-burst-item then summary-update-mounted', solve('summary-visible', [('new-burst-item', N), ('summary-update-mounted', N)], N), 'summary-visible')
check('trace summary-update-mounted then inspect-burst', solve('summary-updating', [('summary-update-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace summary-update-mounted then new-burst-item', solve('summary-updating', [('summary-update-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace close-before-mount then late-details-mounted', solve('expanding-details', [('close-before-mount', N), ('late-details-mounted', N)], N), 'summary-visible')
check('trace late-details-mounted then inspect-burst', solve('closing-details', [('late-details-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace late-details-mounted then new-burst-item', solve('closing-details', [('late-details-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('domain state regression 1: summary_members', solve('condensing', [('summary-mounted', N, {'mount': 2})], N, {}, 'summary_members'), {'phase': 'condensing', 'value': []})
check('domain state regression 2: summary_members', solve('condensing', [('summary-mounted', N, {})], N, {}, 'summary_members'), {'phase': 'summary-visible', 'value': ['a', 'b']})
check('domain state regression 3: items', solve('summary-visible', [('new-burst-item', N, {'item': 'a'})], N, {}, 'items'), {'phase': 'summary-updating', 'value': ['a', 'b']})
check('domain state regression 4: items', solve('summary-visible', [('new-burst-item', N, {'item': 'c'})], N, {}, 'items'), {'phase': 'summary-updating', 'value': ['a', 'b', 'c']})
check('domain state regression 5: detail_members', solve('expanding-details', [('details-mounted', N, {})], N, {}, 'detail_members'), {'phase': 'details-visible', 'value': ['a', 'b']})
check('domain state regression 6: detail_members', solve('closing-details', [('late-details-mounted', N, {})], N, {'detail_members': ['a', 'b']}, 'detail_members'), {'phase': 'summary-visible', 'value': []})
check('domain state regression 7: detail_members', solve('summary-visible', [('inspect-burst', N, {}), ('close-before-mount', N, {}), ('late-details-mounted', N, {})], N, {}, 'detail_members'), {'phase': 'summary-visible', 'value': []})
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
individuals-visible / burst-detectedcondensingcondensingPassed
condensing / summary-mountedsummary-visiblesummary-visiblePassed
condensing / summary-mount-failedindividuals-visibleindividuals-visiblePassed
summary-visible / inspect-burstexpanding-detailsexpanding-detailsPassed
expanding-details / details-mounteddetails-visibledetails-visiblePassed
details-visible / collapse-detailssummary-visiblesummary-visiblePassed
summary-visible / new-burst-itemsummary-updatingsummary-updatingPassed
summary-updating / summary-update-mountedsummary-visiblesummary-visiblePassed
expanding-details / close-before-mountsummary-visibleclosing-detailsFailed
closing-details / late-details-mountedsummary-visiblesummary-visiblePassed
older notification incarnationindividuals-visibleindividuals-visiblePassed
future notification incarnationindividuals-visibleindividuals-visiblePassed
unknown event is inertindividuals-visibleindividuals-visiblePassed
empty delivery batchindividuals-visibleindividuals-visiblePassed
N stale deliveries before current deliverycondensingcondensingPassed
trace burst-detected then summary-mountedsummary-visiblesummary-visiblePassed
trace burst-detected then summary-mount-failedindividuals-visibleindividuals-visiblePassed
trace summary-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace summary-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
trace summary-mount-failed then burst-detectedcondensingcondensingPassed
trace inspect-burst then details-mounteddetails-visibledetails-visiblePassed
trace inspect-burst then close-before-mountsummary-visibleclosing-detailsFailed
trace details-mounted then collapse-detailssummary-visiblesummary-visiblePassed
trace collapse-details then inspect-burstexpanding-detailsexpanding-detailsPassed
trace collapse-details then new-burst-itemsummary-updatingsummary-updatingPassed
trace new-burst-item then summary-update-mountedsummary-visiblesummary-visiblePassed
trace summary-update-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace summary-update-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
trace close-before-mount then late-details-mountedsummary-visiblesummary-visiblePassed
trace late-details-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace late-details-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
domain state regression 1: summary_members{'phase': 'condensing', 'value': []}{'phase': 'condensing', 'value': []}Passed
domain state regression 2: summary_members{'phase': 'summary-visible', 'value': ['a', 'b']}{'phase': 'summary-visible', 'value': ['a', 'b']}Passed
domain state regression 3: items{'phase': 'summary-updating', 'value': ['a', 'b']}{'phase': 'summary-updating', 'value': ['a', 'b']}Passed
domain state regression 4: items{'phase': 'summary-updating', 'value': ['a', 'b', 'c']}{'phase': 'summary-updating', 'value': ['a', 'b', 'c']}Passed
domain state regression 5: detail_members{'phase': 'details-visible', 'value': ['a', 'b']}{'phase': 'details-visible', 'value': ['a', 'b']}Passed
domain state regression 6: detail_members{'phase': 'summary-visible', 'value': []}{'phase': 'summary-visible', 'value': []}Passed
domain state regression 7: detail_members{'phase': 'summary-visible', 'value': []}{'phase': 'summary-visible', 'value': []}Passed

SHA-256 / 9de4538ff5c296f1b63364f324fc2ba0876bafa67f1dfda58fbf3f730941cb41

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(initial, events, generation, payload=None, observe=None):
    table = {('individuals-visible', 'burst-detected'): 'condensing', ('condensing', 'summary-mounted'): 'summary-visible', ('condensing', 'summary-mount-failed'): 'individuals-visible', ('summary-visible', 'inspect-burst'): 'expanding-details', ('expanding-details', 'details-mounted'): 'details-visible', ('details-visible', 'collapse-details'): 'summary-visible', ('summary-visible', 'new-burst-item'): 'summary-updating', ('summary-updating', 'summary-update-mounted'): 'summary-visible', ('expanding-details', 'close-before-mount'): 'details-visible', ('closing-details', 'late-details-mounted'): 'summary-visible'}
    data = json.loads(json.dumps({'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3})) if payload is None else {**json.loads(json.dumps({'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3})), **json.loads(json.dumps(payload))}
    state = initial
    for delivery in events:
        event, event_generation = delivery[:2]
        arg = delivery[2] if len(delivery) > 2 else {}
        if event_generation == generation:
            previous = state
            if event in ('summary-mounted','details-mounted','late-details-mounted','summary-update-mounted') and arg.get('mount',data['mount']) != data['mount']: event = 'unknown-event'
            if event == 'new-burst-item' and arg.get('item','c') not in data['items']: data['items'].append(arg.get('item','c'))
            state = table.get((state, event), state)
            if state == 'summary-visible':
                data['summary_members'] = data['items'][:]
                data['detail_members'] = []
            if state == 'details-visible': data['detail_members'] = data['items'][:]
            if state == 'empty': data['summary_members'] = []; data['detail_members'] = []
    return {'phase': state, 'value': data[observe]} if observe else state
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('individuals-visible / burst-detected', solve('individuals-visible', [('burst-detected', N)], N), 'condensing')
check('condensing / summary-mounted', solve('condensing', [('summary-mounted', N)], N), 'summary-visible')
check('condensing / summary-mount-failed', solve('condensing', [('summary-mount-failed', N)], N), 'individuals-visible')
check('summary-visible / inspect-burst', solve('summary-visible', [('inspect-burst', N)], N), 'expanding-details')
check('expanding-details / details-mounted', solve('expanding-details', [('details-mounted', N)], N), 'details-visible')
check('details-visible / collapse-details', solve('details-visible', [('collapse-details', N)], N), 'summary-visible')
check('summary-visible / new-burst-item', solve('summary-visible', [('new-burst-item', N)], N), 'summary-updating')
check('summary-updating / summary-update-mounted', solve('summary-updating', [('summary-update-mounted', N)], N), 'summary-visible')
check('expanding-details / close-before-mount', solve('expanding-details', [('close-before-mount', N)], N), 'closing-details')
check('closing-details / late-details-mounted', solve('closing-details', [('late-details-mounted', N)], N), 'summary-visible')
check('older notification incarnation', solve('individuals-visible', [('burst-detected', N - 1)], N), 'individuals-visible')
check('future notification incarnation', solve('individuals-visible', [('burst-detected', N + 1)], N), 'individuals-visible')
check('unknown event is inert', solve('individuals-visible', [('unknown-event', N)], N), 'individuals-visible')
check('empty delivery batch', solve('individuals-visible', [], N), 'individuals-visible')
check('N stale deliveries before current delivery', solve('individuals-visible', [('burst-detected', N - 1)] * N + [('burst-detected', N)], N), 'condensing')
check('trace burst-detected then summary-mounted', solve('individuals-visible', [('burst-detected', N), ('summary-mounted', N)], N), 'summary-visible')
check('trace burst-detected then summary-mount-failed', solve('individuals-visible', [('burst-detected', N), ('summary-mount-failed', N)], N), 'individuals-visible')
check('trace summary-mounted then inspect-burst', solve('condensing', [('summary-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace summary-mounted then new-burst-item', solve('condensing', [('summary-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace summary-mount-failed then burst-detected', solve('condensing', [('summary-mount-failed', N), ('burst-detected', N)], N), 'condensing')
check('trace inspect-burst then details-mounted', solve('summary-visible', [('inspect-burst', N), ('details-mounted', N)], N), 'details-visible')
check('trace inspect-burst then close-before-mount', solve('summary-visible', [('inspect-burst', N), ('close-before-mount', N)], N), 'closing-details')
check('trace details-mounted then collapse-details', solve('expanding-details', [('details-mounted', N), ('collapse-details', N)], N), 'summary-visible')
check('trace collapse-details then inspect-burst', solve('details-visible', [('collapse-details', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace collapse-details then new-burst-item', solve('details-visible', [('collapse-details', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace new-burst-item then summary-update-mounted', solve('summary-visible', [('new-burst-item', N), ('summary-update-mounted', N)], N), 'summary-visible')
check('trace summary-update-mounted then inspect-burst', solve('summary-updating', [('summary-update-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace summary-update-mounted then new-burst-item', solve('summary-updating', [('summary-update-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace close-before-mount then late-details-mounted', solve('expanding-details', [('close-before-mount', N), ('late-details-mounted', N)], N), 'summary-visible')
check('trace late-details-mounted then inspect-burst', solve('closing-details', [('late-details-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace late-details-mounted then new-burst-item', solve('closing-details', [('late-details-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('domain state regression 1: summary_members', solve('condensing', [('summary-mounted', N, {'mount': 2})], N, {}, 'summary_members'), {'phase': 'condensing', 'value': []})
check('domain state regression 2: summary_members', solve('condensing', [('summary-mounted', N, {})], N, {}, 'summary_members'), {'phase': 'summary-visible', 'value': ['a', 'b']})
check('domain state regression 3: items', solve('summary-visible', [('new-burst-item', N, {'item': 'a'})], N, {}, 'items'), {'phase': 'summary-updating', 'value': ['a', 'b']})
check('domain state regression 4: items', solve('summary-visible', [('new-burst-item', N, {'item': 'c'})], N, {}, 'items'), {'phase': 'summary-updating', 'value': ['a', 'b', 'c']})
check('domain state regression 5: detail_members', solve('expanding-details', [('details-mounted', N, {})], N, {}, 'detail_members'), {'phase': 'details-visible', 'value': ['a', 'b']})
check('domain state regression 6: detail_members', solve('closing-details', [('late-details-mounted', N, {})], N, {'detail_members': ['a', 'b']}, 'detail_members'), {'phase': 'summary-visible', 'value': []})
check('domain state regression 7: detail_members', solve('summary-visible', [('inspect-burst', N, {}), ('close-before-mount', N, {}), ('late-details-mounted', N, {})], N, {}, 'detail_members'), {'phase': 'summary-visible', 'value': []})
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
individuals-visible / burst-detectedcondensingcondensingPassed
condensing / summary-mountedsummary-visiblesummary-visiblePassed
condensing / summary-mount-failedindividuals-visibleindividuals-visiblePassed
summary-visible / inspect-burstexpanding-detailsexpanding-detailsPassed
expanding-details / details-mounteddetails-visibledetails-visiblePassed
details-visible / collapse-detailssummary-visiblesummary-visiblePassed
summary-visible / new-burst-itemsummary-updatingsummary-updatingPassed
summary-updating / summary-update-mountedsummary-visiblesummary-visiblePassed
expanding-details / close-before-mountdetails-visibleclosing-detailsFailed
closing-details / late-details-mountedsummary-visiblesummary-visiblePassed
older notification incarnationindividuals-visibleindividuals-visiblePassed
future notification incarnationindividuals-visibleindividuals-visiblePassed
unknown event is inertindividuals-visibleindividuals-visiblePassed
empty delivery batchindividuals-visibleindividuals-visiblePassed
N stale deliveries before current deliverycondensingcondensingPassed
trace burst-detected then summary-mountedsummary-visiblesummary-visiblePassed
trace burst-detected then summary-mount-failedindividuals-visibleindividuals-visiblePassed
trace summary-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace summary-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
trace summary-mount-failed then burst-detectedcondensingcondensingPassed
trace inspect-burst then details-mounteddetails-visibledetails-visiblePassed
trace inspect-burst then close-before-mountdetails-visibleclosing-detailsFailed
trace details-mounted then collapse-detailssummary-visiblesummary-visiblePassed
trace collapse-details then inspect-burstexpanding-detailsexpanding-detailsPassed
trace collapse-details then new-burst-itemsummary-updatingsummary-updatingPassed
trace new-burst-item then summary-update-mountedsummary-visiblesummary-visiblePassed
trace summary-update-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace summary-update-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
trace close-before-mount then late-details-mounteddetails-visiblesummary-visibleFailed
trace late-details-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace late-details-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
domain state regression 1: summary_members{'phase': 'condensing', 'value': []}{'phase': 'condensing', 'value': []}Passed
domain state regression 2: summary_members{'phase': 'summary-visible', 'value': ['a', 'b']}{'phase': 'summary-visible', 'value': ['a', 'b']}Passed
domain state regression 3: items{'phase': 'summary-updating', 'value': ['a', 'b']}{'phase': 'summary-updating', 'value': ['a', 'b']}Passed
domain state regression 4: items{'phase': 'summary-updating', 'value': ['a', 'b', 'c']}{'phase': 'summary-updating', 'value': ['a', 'b', 'c']}Passed
domain state regression 5: detail_members{'phase': 'details-visible', 'value': ['a', 'b']}{'phase': 'details-visible', 'value': ['a', 'b']}Passed
domain state regression 6: detail_members{'phase': 'summary-visible', 'value': []}{'phase': 'summary-visible', 'value': []}Passed
domain state regression 7: detail_members{'phase': 'details-visible', 'value': ['a', 'b']}{'phase': 'summary-visible', 'value': []}Failed

SHA-256 / 5d9f748a4d596ff36cf29cc16ef1c5c29410f03f66b27fa663393f35f97c923f

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(initial, events, generation, payload=None, observe=None):
    table = {('individuals-visible', 'burst-detected'): 'condensing', ('condensing', 'summary-mounted'): 'summary-visible', ('condensing', 'summary-mount-failed'): 'individuals-visible', ('summary-visible', 'inspect-burst'): 'expanding-details', ('expanding-details', 'details-mounted'): 'details-visible', ('details-visible', 'collapse-details'): 'summary-visible', ('summary-visible', 'new-burst-item'): 'summary-updating', ('summary-updating', 'summary-update-mounted'): 'summary-visible', ('expanding-details', 'close-before-mount'): 'closing-details', ('closing-details', 'late-details-mounted'): 'summary-visible'}
    data = json.loads(json.dumps({'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3})) if payload is None else {**json.loads(json.dumps({'items': ['a', 'b'], 'summary_members': [], 'detail_members': [], 'mount': 3})), **json.loads(json.dumps(payload))}
    state = initial
    for delivery in events:
        event, event_generation = delivery[:2]
        arg = delivery[2] if len(delivery) > 2 else {}
        if event_generation == generation:
            previous = state
            if event in ('summary-mounted','details-mounted','late-details-mounted','summary-update-mounted') and arg.get('mount',data['mount']) != data['mount']: event = 'unknown-event'
            if event == 'new-burst-item' and arg.get('item','c') not in data['items']: data['items'].append(arg.get('item','c'))
            state = table.get((state, event), state)
            if state == 'summary-visible':
                data['summary_members'] = data['items'][:]
                data['detail_members'] = []
            if state == 'details-visible': data['detail_members'] = data['items'][:]
            if state == 'empty': data['summary_members'] = []; data['detail_members'] = []
    return {'phase': state, 'value': data[observe]} if observe else state
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('individuals-visible / burst-detected', solve('individuals-visible', [('burst-detected', N)], N), 'condensing')
check('condensing / summary-mounted', solve('condensing', [('summary-mounted', N)], N), 'summary-visible')
check('condensing / summary-mount-failed', solve('condensing', [('summary-mount-failed', N)], N), 'individuals-visible')
check('summary-visible / inspect-burst', solve('summary-visible', [('inspect-burst', N)], N), 'expanding-details')
check('expanding-details / details-mounted', solve('expanding-details', [('details-mounted', N)], N), 'details-visible')
check('details-visible / collapse-details', solve('details-visible', [('collapse-details', N)], N), 'summary-visible')
check('summary-visible / new-burst-item', solve('summary-visible', [('new-burst-item', N)], N), 'summary-updating')
check('summary-updating / summary-update-mounted', solve('summary-updating', [('summary-update-mounted', N)], N), 'summary-visible')
check('expanding-details / close-before-mount', solve('expanding-details', [('close-before-mount', N)], N), 'closing-details')
check('closing-details / late-details-mounted', solve('closing-details', [('late-details-mounted', N)], N), 'summary-visible')
check('older notification incarnation', solve('individuals-visible', [('burst-detected', N - 1)], N), 'individuals-visible')
check('future notification incarnation', solve('individuals-visible', [('burst-detected', N + 1)], N), 'individuals-visible')
check('unknown event is inert', solve('individuals-visible', [('unknown-event', N)], N), 'individuals-visible')
check('empty delivery batch', solve('individuals-visible', [], N), 'individuals-visible')
check('N stale deliveries before current delivery', solve('individuals-visible', [('burst-detected', N - 1)] * N + [('burst-detected', N)], N), 'condensing')
check('trace burst-detected then summary-mounted', solve('individuals-visible', [('burst-detected', N), ('summary-mounted', N)], N), 'summary-visible')
check('trace burst-detected then summary-mount-failed', solve('individuals-visible', [('burst-detected', N), ('summary-mount-failed', N)], N), 'individuals-visible')
check('trace summary-mounted then inspect-burst', solve('condensing', [('summary-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace summary-mounted then new-burst-item', solve('condensing', [('summary-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace summary-mount-failed then burst-detected', solve('condensing', [('summary-mount-failed', N), ('burst-detected', N)], N), 'condensing')
check('trace inspect-burst then details-mounted', solve('summary-visible', [('inspect-burst', N), ('details-mounted', N)], N), 'details-visible')
check('trace inspect-burst then close-before-mount', solve('summary-visible', [('inspect-burst', N), ('close-before-mount', N)], N), 'closing-details')
check('trace details-mounted then collapse-details', solve('expanding-details', [('details-mounted', N), ('collapse-details', N)], N), 'summary-visible')
check('trace collapse-details then inspect-burst', solve('details-visible', [('collapse-details', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace collapse-details then new-burst-item', solve('details-visible', [('collapse-details', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace new-burst-item then summary-update-mounted', solve('summary-visible', [('new-burst-item', N), ('summary-update-mounted', N)], N), 'summary-visible')
check('trace summary-update-mounted then inspect-burst', solve('summary-updating', [('summary-update-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace summary-update-mounted then new-burst-item', solve('summary-updating', [('summary-update-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('trace close-before-mount then late-details-mounted', solve('expanding-details', [('close-before-mount', N), ('late-details-mounted', N)], N), 'summary-visible')
check('trace late-details-mounted then inspect-burst', solve('closing-details', [('late-details-mounted', N), ('inspect-burst', N)], N), 'expanding-details')
check('trace late-details-mounted then new-burst-item', solve('closing-details', [('late-details-mounted', N), ('new-burst-item', N)], N), 'summary-updating')
check('domain state regression 1: summary_members', solve('condensing', [('summary-mounted', N, {'mount': 2})], N, {}, 'summary_members'), {'phase': 'condensing', 'value': []})
check('domain state regression 2: summary_members', solve('condensing', [('summary-mounted', N, {})], N, {}, 'summary_members'), {'phase': 'summary-visible', 'value': ['a', 'b']})
check('domain state regression 3: items', solve('summary-visible', [('new-burst-item', N, {'item': 'a'})], N, {}, 'items'), {'phase': 'summary-updating', 'value': ['a', 'b']})
check('domain state regression 4: items', solve('summary-visible', [('new-burst-item', N, {'item': 'c'})], N, {}, 'items'), {'phase': 'summary-updating', 'value': ['a', 'b', 'c']})
check('domain state regression 5: detail_members', solve('expanding-details', [('details-mounted', N, {})], N, {}, 'detail_members'), {'phase': 'details-visible', 'value': ['a', 'b']})
check('domain state regression 6: detail_members', solve('closing-details', [('late-details-mounted', N, {})], N, {'detail_members': ['a', 'b']}, 'detail_members'), {'phase': 'summary-visible', 'value': []})
check('domain state regression 7: detail_members', solve('summary-visible', [('inspect-burst', N, {}), ('close-before-mount', N, {}), ('late-details-mounted', N, {})], N, {}, 'detail_members'), {'phase': 'summary-visible', 'value': []})
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
individuals-visible / burst-detectedcondensingcondensingPassed
condensing / summary-mountedsummary-visiblesummary-visiblePassed
condensing / summary-mount-failedindividuals-visibleindividuals-visiblePassed
summary-visible / inspect-burstexpanding-detailsexpanding-detailsPassed
expanding-details / details-mounteddetails-visibledetails-visiblePassed
details-visible / collapse-detailssummary-visiblesummary-visiblePassed
summary-visible / new-burst-itemsummary-updatingsummary-updatingPassed
summary-updating / summary-update-mountedsummary-visiblesummary-visiblePassed
expanding-details / close-before-mountclosing-detailsclosing-detailsPassed
closing-details / late-details-mountedsummary-visiblesummary-visiblePassed
older notification incarnationindividuals-visibleindividuals-visiblePassed
future notification incarnationindividuals-visibleindividuals-visiblePassed
unknown event is inertindividuals-visibleindividuals-visiblePassed
empty delivery batchindividuals-visibleindividuals-visiblePassed
N stale deliveries before current deliverycondensingcondensingPassed
trace burst-detected then summary-mountedsummary-visiblesummary-visiblePassed
trace burst-detected then summary-mount-failedindividuals-visibleindividuals-visiblePassed
trace summary-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace summary-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
trace summary-mount-failed then burst-detectedcondensingcondensingPassed
trace inspect-burst then details-mounteddetails-visibledetails-visiblePassed
trace inspect-burst then close-before-mountclosing-detailsclosing-detailsPassed
trace details-mounted then collapse-detailssummary-visiblesummary-visiblePassed
trace collapse-details then inspect-burstexpanding-detailsexpanding-detailsPassed
trace collapse-details then new-burst-itemsummary-updatingsummary-updatingPassed
trace new-burst-item then summary-update-mountedsummary-visiblesummary-visiblePassed
trace summary-update-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace summary-update-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
trace close-before-mount then late-details-mountedsummary-visiblesummary-visiblePassed
trace late-details-mounted then inspect-burstexpanding-detailsexpanding-detailsPassed
trace late-details-mounted then new-burst-itemsummary-updatingsummary-updatingPassed
domain state regression 1: summary_members{'phase': 'condensing', 'value': []}{'phase': 'condensing', 'value': []}Passed
domain state regression 2: summary_members{'phase': 'summary-visible', 'value': ['a', 'b']}{'phase': 'summary-visible', 'value': ['a', 'b']}Passed
domain state regression 3: items{'phase': 'summary-updating', 'value': ['a', 'b']}{'phase': 'summary-updating', 'value': ['a', 'b']}Passed
domain state regression 4: items{'phase': 'summary-updating', 'value': ['a', 'b', 'c']}{'phase': 'summary-updating', 'value': ['a', 'b', 'c']}Passed
domain state regression 5: detail_members{'phase': 'details-visible', 'value': ['a', 'b']}{'phase': 'details-visible', 'value': ['a', 'b']}Passed
domain state regression 6: detail_members{'phase': 'summary-visible', 'value': []}{'phase': 'summary-visible', 'value': []}Passed
domain state regression 7: detail_members{'phase': 'summary-visible', 'value': []}{'phase': 'summary-visible', 'value': []}Passed

SHA-256 / cbddf1054d0bd2f1856cf5c4fc094455dfe5182ed2397a61b0150b1180aa061f

Verification & scope

Stipulated single-notification state and policy model only. Event delivery and acknowledgements are explicit test inputs. No DOM, accessibility announcements, live timers, networking, actual rendering, or production-platform conformance is simulated. 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 2026-09-29T14:42:39.563796+00:00.

Case digest / 2cb3d3830dc0305bf0a9797235cfc46ddca07a2905e55a7990d19b98efb1aecb