FA-34476 / Notification interfaces / Open access
Banner to inbox promotion: save-failure from saving-without-banner · case 01
The save-failure event leaves a notification in gone instead of recovery-banner.
ROOT CAUSE
Failed retention after expiry leaves no recovery surface.
VERIFIED REPAIR
Commit the saving-without-banner / save-failure transition to recovery-banner; preserve the other explicitly stipulated transitions.
Unsuccessful approach: Claiming a retained copy hides the loss.
Case contract
Banner to inbox promotion is a bounded visual-notification workflow with mutable policy state {'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2}. Its default transition relation is {('banner', 'retain-in-inbox'): 'saving', ('saving', 'save-success'): 'both', ('saving', 'save-failure'): 'save-error', ('both', 'banner-exposure-end'): 'inbox-only', ('save-error', 'retry-retention'): 'saving', ('saving', 'banner-exposure-end'): 'saving-without-banner', ('saving-without-banner', 'save-success'): 'inbox-only', ('saving-without-banner', 'save-failure'): 'recovery-banner', ('inbox-only', 'show-banner-again'): 'repromoting', ('repromoting', 'banner-mounted'): 'both'}; 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 = {('banner', 'retain-in-inbox'): 'saving', ('saving', 'save-success'): 'both', ('saving', 'save-failure'): 'save-error', ('both', 'banner-exposure-end'): 'inbox-only', ('save-error', 'retry-retention'): 'saving', ('saving', 'banner-exposure-end'): 'saving-without-banner', ('saving-without-banner', 'save-success'): 'inbox-only', ('saving-without-banner', 'save-failure'): 'gone', ('inbox-only', 'show-banner-again'): 'repromoting', ('repromoting', 'banner-mounted'): 'both'}
data = json.loads(json.dumps({'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2})) if payload is None else {**json.loads(json.dumps({'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2})), **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 ('save-success','save-failure') and arg.get('revision',data['save_revision']) != data['save_revision']: event = 'unknown-event'
state = table.get((state, event), state)
if state in ('both','inbox-only') and data['item'] not in data['inbox']: data['inbox'].append(data['item'])
data['banner'] = state in ('banner','both','saving','save-error','recovery-banner')
if state == 'gone': data['inbox'] = [x for x in data['inbox'] if x != data['item']]
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('banner / retain-in-inbox', solve('banner', [('retain-in-inbox', N)], N), 'saving')
check('saving / save-success', solve('saving', [('save-success', N)], N), 'both')
check('saving / save-failure', solve('saving', [('save-failure', N)], N), 'save-error')
check('both / banner-exposure-end', solve('both', [('banner-exposure-end', N)], N), 'inbox-only')
check('save-error / retry-retention', solve('save-error', [('retry-retention', N)], N), 'saving')
check('saving / banner-exposure-end', solve('saving', [('banner-exposure-end', N)], N), 'saving-without-banner')
check('saving-without-banner / save-success', solve('saving-without-banner', [('save-success', N)], N), 'inbox-only')
check('saving-without-banner / save-failure', solve('saving-without-banner', [('save-failure', N)], N), 'recovery-banner')
check('inbox-only / show-banner-again', solve('inbox-only', [('show-banner-again', N)], N), 'repromoting')
check('repromoting / banner-mounted', solve('repromoting', [('banner-mounted', N)], N), 'both')
check('older notification incarnation', solve('banner', [('retain-in-inbox', N - 1)], N), 'banner')
check('future notification incarnation', solve('banner', [('retain-in-inbox', N + 1)], N), 'banner')
check('unknown event is inert', solve('banner', [('unknown-event', N)], N), 'banner')
check('empty delivery batch', solve('banner', [], N), 'banner')
check('N stale deliveries before current delivery', solve('banner', [('retain-in-inbox', N - 1)] * N + [('retain-in-inbox', N)], N), 'saving')
check('trace retain-in-inbox then save-success', solve('banner', [('retain-in-inbox', N), ('save-success', N)], N), 'both')
check('trace retain-in-inbox then save-failure', solve('banner', [('retain-in-inbox', N), ('save-failure', N)], N), 'save-error')
check('trace retain-in-inbox then banner-exposure-end', solve('banner', [('retain-in-inbox', N), ('banner-exposure-end', N)], N), 'saving-without-banner')
check('trace save-success then banner-exposure-end', solve('saving', [('save-success', N), ('banner-exposure-end', N)], N), 'inbox-only')
check('trace save-failure then retry-retention', solve('saving', [('save-failure', N), ('retry-retention', N)], N), 'saving')
check('trace banner-exposure-end then show-banner-again', solve('both', [('banner-exposure-end', N), ('show-banner-again', N)], N), 'repromoting')
check('trace retry-retention then save-success', solve('save-error', [('retry-retention', N), ('save-success', N)], N), 'both')
check('trace retry-retention then save-failure', solve('save-error', [('retry-retention', N), ('save-failure', N)], N), 'save-error')
check('trace retry-retention then banner-exposure-end', solve('save-error', [('retry-retention', N), ('banner-exposure-end', N)], N), 'saving-without-banner')
check('trace banner-exposure-end then save-success', solve('saving', [('banner-exposure-end', N), ('save-success', N)], N), 'inbox-only')
check('trace banner-exposure-end then save-failure', solve('saving', [('banner-exposure-end', N), ('save-failure', N)], N), 'recovery-banner')
check('trace save-success then show-banner-again', solve('saving-without-banner', [('save-success', N), ('show-banner-again', N)], N), 'repromoting')
check('trace show-banner-again then banner-mounted', solve('inbox-only', [('show-banner-again', N), ('banner-mounted', N)], N), 'both')
check('trace banner-mounted then banner-exposure-end', solve('repromoting', [('banner-mounted', N), ('banner-exposure-end', N)], N), 'inbox-only')
check('domain state regression 1: inbox', solve('saving', [('save-success', N, {'revision': 1})], N, {}, 'inbox'), {'phase': 'saving', 'value': []})
check('domain state regression 2: inbox', solve('saving', [('save-success', N, {'revision': 2})], N, {'inbox': ['other']}, 'inbox'), {'phase': 'both', 'value': ['other', 'n']})
check('domain state regression 3: inbox', solve('both', [('banner-exposure-end', N, {})], N, {'inbox': ['n']}, 'inbox'), {'phase': 'inbox-only', 'value': ['n']})
check('domain state regression 4: banner', solve('both', [('banner-exposure-end', N, {})], N, {'inbox': ['n']}, 'banner'), {'phase': 'inbox-only', 'value': False})
check('domain state regression 5: banner', solve('saving-without-banner', [('save-failure', N, {})], N, {'banner': False}, 'banner'), {'phase': 'recovery-banner', 'value': True})
check('domain state regression 6: banner', solve('saving-without-banner', [('save-success', N, {})], N, {'banner': False}, 'banner'), {'phase': 'inbox-only', 'value': False})
check('domain state regression 7: banner', solve('banner', [('retain-in-inbox', N, {}), ('banner-exposure-end', N, {}), ('save-success', N, {})], N, {}, 'banner'), {'phase': 'inbox-only', 'value': False})
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| banner / retain-in-inbox | saving | saving | Passed |
| saving / save-success | both | both | Passed |
| saving / save-failure | save-error | save-error | Passed |
| both / banner-exposure-end | inbox-only | inbox-only | Passed |
| save-error / retry-retention | saving | saving | Passed |
| saving / banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| saving-without-banner / save-success | inbox-only | inbox-only | Passed |
| saving-without-banner / save-failure | gone | recovery-banner | Failed |
| inbox-only / show-banner-again | repromoting | repromoting | Passed |
| repromoting / banner-mounted | both | both | Passed |
| older notification incarnation | banner | banner | Passed |
| future notification incarnation | banner | banner | Passed |
| unknown event is inert | banner | banner | Passed |
| empty delivery batch | banner | banner | Passed |
| N stale deliveries before current delivery | saving | saving | Passed |
| trace retain-in-inbox then save-success | both | both | Passed |
| trace retain-in-inbox then save-failure | save-error | save-error | Passed |
| trace retain-in-inbox then banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| trace save-success then banner-exposure-end | inbox-only | inbox-only | Passed |
| trace save-failure then retry-retention | saving | saving | Passed |
| trace banner-exposure-end then show-banner-again | repromoting | repromoting | Passed |
| trace retry-retention then save-success | both | both | Passed |
| trace retry-retention then save-failure | save-error | save-error | Passed |
| trace retry-retention then banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| trace banner-exposure-end then save-success | inbox-only | inbox-only | Passed |
| trace banner-exposure-end then save-failure | gone | recovery-banner | Failed |
| trace save-success then show-banner-again | repromoting | repromoting | Passed |
| trace show-banner-again then banner-mounted | both | both | Passed |
| trace banner-mounted then banner-exposure-end | inbox-only | inbox-only | Passed |
| domain state regression 1: inbox | {'phase': 'saving', 'value': []} | {'phase': 'saving', 'value': []} | Passed |
| domain state regression 2: inbox | {'phase': 'both', 'value': ['other', 'n']} | {'phase': 'both', 'value': ['other', 'n']} | Passed |
| domain state regression 3: inbox | {'phase': 'inbox-only', 'value': ['n']} | {'phase': 'inbox-only', 'value': ['n']} | Passed |
| domain state regression 4: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
| domain state regression 5: banner | {'phase': 'gone', 'value': False} | {'phase': 'recovery-banner', 'value': True} | Failed |
| domain state regression 6: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
| domain state regression 7: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
SHA-256 / 5944ab93dff29762db71f5ae02e6ba236ca8bd5254d457e4646e34036a4b25d2
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 = {('banner', 'retain-in-inbox'): 'saving', ('saving', 'save-success'): 'both', ('saving', 'save-failure'): 'save-error', ('both', 'banner-exposure-end'): 'inbox-only', ('save-error', 'retry-retention'): 'saving', ('saving', 'banner-exposure-end'): 'saving-without-banner', ('saving-without-banner', 'save-success'): 'inbox-only', ('saving-without-banner', 'save-failure'): 'inbox-only', ('inbox-only', 'show-banner-again'): 'repromoting', ('repromoting', 'banner-mounted'): 'both'}
data = json.loads(json.dumps({'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2})) if payload is None else {**json.loads(json.dumps({'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2})), **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 ('save-success','save-failure') and arg.get('revision',data['save_revision']) != data['save_revision']: event = 'unknown-event'
state = table.get((state, event), state)
if state in ('both','inbox-only') and data['item'] not in data['inbox']: data['inbox'].append(data['item'])
data['banner'] = state in ('banner','both','saving','save-error','recovery-banner')
if state == 'gone': data['inbox'] = [x for x in data['inbox'] if x != data['item']]
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('banner / retain-in-inbox', solve('banner', [('retain-in-inbox', N)], N), 'saving')
check('saving / save-success', solve('saving', [('save-success', N)], N), 'both')
check('saving / save-failure', solve('saving', [('save-failure', N)], N), 'save-error')
check('both / banner-exposure-end', solve('both', [('banner-exposure-end', N)], N), 'inbox-only')
check('save-error / retry-retention', solve('save-error', [('retry-retention', N)], N), 'saving')
check('saving / banner-exposure-end', solve('saving', [('banner-exposure-end', N)], N), 'saving-without-banner')
check('saving-without-banner / save-success', solve('saving-without-banner', [('save-success', N)], N), 'inbox-only')
check('saving-without-banner / save-failure', solve('saving-without-banner', [('save-failure', N)], N), 'recovery-banner')
check('inbox-only / show-banner-again', solve('inbox-only', [('show-banner-again', N)], N), 'repromoting')
check('repromoting / banner-mounted', solve('repromoting', [('banner-mounted', N)], N), 'both')
check('older notification incarnation', solve('banner', [('retain-in-inbox', N - 1)], N), 'banner')
check('future notification incarnation', solve('banner', [('retain-in-inbox', N + 1)], N), 'banner')
check('unknown event is inert', solve('banner', [('unknown-event', N)], N), 'banner')
check('empty delivery batch', solve('banner', [], N), 'banner')
check('N stale deliveries before current delivery', solve('banner', [('retain-in-inbox', N - 1)] * N + [('retain-in-inbox', N)], N), 'saving')
check('trace retain-in-inbox then save-success', solve('banner', [('retain-in-inbox', N), ('save-success', N)], N), 'both')
check('trace retain-in-inbox then save-failure', solve('banner', [('retain-in-inbox', N), ('save-failure', N)], N), 'save-error')
check('trace retain-in-inbox then banner-exposure-end', solve('banner', [('retain-in-inbox', N), ('banner-exposure-end', N)], N), 'saving-without-banner')
check('trace save-success then banner-exposure-end', solve('saving', [('save-success', N), ('banner-exposure-end', N)], N), 'inbox-only')
check('trace save-failure then retry-retention', solve('saving', [('save-failure', N), ('retry-retention', N)], N), 'saving')
check('trace banner-exposure-end then show-banner-again', solve('both', [('banner-exposure-end', N), ('show-banner-again', N)], N), 'repromoting')
check('trace retry-retention then save-success', solve('save-error', [('retry-retention', N), ('save-success', N)], N), 'both')
check('trace retry-retention then save-failure', solve('save-error', [('retry-retention', N), ('save-failure', N)], N), 'save-error')
check('trace retry-retention then banner-exposure-end', solve('save-error', [('retry-retention', N), ('banner-exposure-end', N)], N), 'saving-without-banner')
check('trace banner-exposure-end then save-success', solve('saving', [('banner-exposure-end', N), ('save-success', N)], N), 'inbox-only')
check('trace banner-exposure-end then save-failure', solve('saving', [('banner-exposure-end', N), ('save-failure', N)], N), 'recovery-banner')
check('trace save-success then show-banner-again', solve('saving-without-banner', [('save-success', N), ('show-banner-again', N)], N), 'repromoting')
check('trace show-banner-again then banner-mounted', solve('inbox-only', [('show-banner-again', N), ('banner-mounted', N)], N), 'both')
check('trace banner-mounted then banner-exposure-end', solve('repromoting', [('banner-mounted', N), ('banner-exposure-end', N)], N), 'inbox-only')
check('domain state regression 1: inbox', solve('saving', [('save-success', N, {'revision': 1})], N, {}, 'inbox'), {'phase': 'saving', 'value': []})
check('domain state regression 2: inbox', solve('saving', [('save-success', N, {'revision': 2})], N, {'inbox': ['other']}, 'inbox'), {'phase': 'both', 'value': ['other', 'n']})
check('domain state regression 3: inbox', solve('both', [('banner-exposure-end', N, {})], N, {'inbox': ['n']}, 'inbox'), {'phase': 'inbox-only', 'value': ['n']})
check('domain state regression 4: banner', solve('both', [('banner-exposure-end', N, {})], N, {'inbox': ['n']}, 'banner'), {'phase': 'inbox-only', 'value': False})
check('domain state regression 5: banner', solve('saving-without-banner', [('save-failure', N, {})], N, {'banner': False}, 'banner'), {'phase': 'recovery-banner', 'value': True})
check('domain state regression 6: banner', solve('saving-without-banner', [('save-success', N, {})], N, {'banner': False}, 'banner'), {'phase': 'inbox-only', 'value': False})
check('domain state regression 7: banner', solve('banner', [('retain-in-inbox', N, {}), ('banner-exposure-end', N, {}), ('save-success', N, {})], N, {}, 'banner'), {'phase': 'inbox-only', 'value': False})
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| banner / retain-in-inbox | saving | saving | Passed |
| saving / save-success | both | both | Passed |
| saving / save-failure | save-error | save-error | Passed |
| both / banner-exposure-end | inbox-only | inbox-only | Passed |
| save-error / retry-retention | saving | saving | Passed |
| saving / banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| saving-without-banner / save-success | inbox-only | inbox-only | Passed |
| saving-without-banner / save-failure | inbox-only | recovery-banner | Failed |
| inbox-only / show-banner-again | repromoting | repromoting | Passed |
| repromoting / banner-mounted | both | both | Passed |
| older notification incarnation | banner | banner | Passed |
| future notification incarnation | banner | banner | Passed |
| unknown event is inert | banner | banner | Passed |
| empty delivery batch | banner | banner | Passed |
| N stale deliveries before current delivery | saving | saving | Passed |
| trace retain-in-inbox then save-success | both | both | Passed |
| trace retain-in-inbox then save-failure | save-error | save-error | Passed |
| trace retain-in-inbox then banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| trace save-success then banner-exposure-end | inbox-only | inbox-only | Passed |
| trace save-failure then retry-retention | saving | saving | Passed |
| trace banner-exposure-end then show-banner-again | repromoting | repromoting | Passed |
| trace retry-retention then save-success | both | both | Passed |
| trace retry-retention then save-failure | save-error | save-error | Passed |
| trace retry-retention then banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| trace banner-exposure-end then save-success | inbox-only | inbox-only | Passed |
| trace banner-exposure-end then save-failure | inbox-only | recovery-banner | Failed |
| trace save-success then show-banner-again | repromoting | repromoting | Passed |
| trace show-banner-again then banner-mounted | both | both | Passed |
| trace banner-mounted then banner-exposure-end | inbox-only | inbox-only | Passed |
| domain state regression 1: inbox | {'phase': 'saving', 'value': []} | {'phase': 'saving', 'value': []} | Passed |
| domain state regression 2: inbox | {'phase': 'both', 'value': ['other', 'n']} | {'phase': 'both', 'value': ['other', 'n']} | Passed |
| domain state regression 3: inbox | {'phase': 'inbox-only', 'value': ['n']} | {'phase': 'inbox-only', 'value': ['n']} | Passed |
| domain state regression 4: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
| domain state regression 5: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'recovery-banner', 'value': True} | Failed |
| domain state regression 6: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
| domain state regression 7: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
SHA-256 / 0a8eeb9be1b2c94f59748d11588a6eb7f25db72946d0e6bb70705ce932b71b07
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 = {('banner', 'retain-in-inbox'): 'saving', ('saving', 'save-success'): 'both', ('saving', 'save-failure'): 'save-error', ('both', 'banner-exposure-end'): 'inbox-only', ('save-error', 'retry-retention'): 'saving', ('saving', 'banner-exposure-end'): 'saving-without-banner', ('saving-without-banner', 'save-success'): 'inbox-only', ('saving-without-banner', 'save-failure'): 'recovery-banner', ('inbox-only', 'show-banner-again'): 'repromoting', ('repromoting', 'banner-mounted'): 'both'}
data = json.loads(json.dumps({'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2})) if payload is None else {**json.loads(json.dumps({'banner': True, 'inbox': [], 'item': 'n', 'save_revision': 2})), **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 ('save-success','save-failure') and arg.get('revision',data['save_revision']) != data['save_revision']: event = 'unknown-event'
state = table.get((state, event), state)
if state in ('both','inbox-only') and data['item'] not in data['inbox']: data['inbox'].append(data['item'])
data['banner'] = state in ('banner','both','saving','save-error','recovery-banner')
if state == 'gone': data['inbox'] = [x for x in data['inbox'] if x != data['item']]
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('banner / retain-in-inbox', solve('banner', [('retain-in-inbox', N)], N), 'saving')
check('saving / save-success', solve('saving', [('save-success', N)], N), 'both')
check('saving / save-failure', solve('saving', [('save-failure', N)], N), 'save-error')
check('both / banner-exposure-end', solve('both', [('banner-exposure-end', N)], N), 'inbox-only')
check('save-error / retry-retention', solve('save-error', [('retry-retention', N)], N), 'saving')
check('saving / banner-exposure-end', solve('saving', [('banner-exposure-end', N)], N), 'saving-without-banner')
check('saving-without-banner / save-success', solve('saving-without-banner', [('save-success', N)], N), 'inbox-only')
check('saving-without-banner / save-failure', solve('saving-without-banner', [('save-failure', N)], N), 'recovery-banner')
check('inbox-only / show-banner-again', solve('inbox-only', [('show-banner-again', N)], N), 'repromoting')
check('repromoting / banner-mounted', solve('repromoting', [('banner-mounted', N)], N), 'both')
check('older notification incarnation', solve('banner', [('retain-in-inbox', N - 1)], N), 'banner')
check('future notification incarnation', solve('banner', [('retain-in-inbox', N + 1)], N), 'banner')
check('unknown event is inert', solve('banner', [('unknown-event', N)], N), 'banner')
check('empty delivery batch', solve('banner', [], N), 'banner')
check('N stale deliveries before current delivery', solve('banner', [('retain-in-inbox', N - 1)] * N + [('retain-in-inbox', N)], N), 'saving')
check('trace retain-in-inbox then save-success', solve('banner', [('retain-in-inbox', N), ('save-success', N)], N), 'both')
check('trace retain-in-inbox then save-failure', solve('banner', [('retain-in-inbox', N), ('save-failure', N)], N), 'save-error')
check('trace retain-in-inbox then banner-exposure-end', solve('banner', [('retain-in-inbox', N), ('banner-exposure-end', N)], N), 'saving-without-banner')
check('trace save-success then banner-exposure-end', solve('saving', [('save-success', N), ('banner-exposure-end', N)], N), 'inbox-only')
check('trace save-failure then retry-retention', solve('saving', [('save-failure', N), ('retry-retention', N)], N), 'saving')
check('trace banner-exposure-end then show-banner-again', solve('both', [('banner-exposure-end', N), ('show-banner-again', N)], N), 'repromoting')
check('trace retry-retention then save-success', solve('save-error', [('retry-retention', N), ('save-success', N)], N), 'both')
check('trace retry-retention then save-failure', solve('save-error', [('retry-retention', N), ('save-failure', N)], N), 'save-error')
check('trace retry-retention then banner-exposure-end', solve('save-error', [('retry-retention', N), ('banner-exposure-end', N)], N), 'saving-without-banner')
check('trace banner-exposure-end then save-success', solve('saving', [('banner-exposure-end', N), ('save-success', N)], N), 'inbox-only')
check('trace banner-exposure-end then save-failure', solve('saving', [('banner-exposure-end', N), ('save-failure', N)], N), 'recovery-banner')
check('trace save-success then show-banner-again', solve('saving-without-banner', [('save-success', N), ('show-banner-again', N)], N), 'repromoting')
check('trace show-banner-again then banner-mounted', solve('inbox-only', [('show-banner-again', N), ('banner-mounted', N)], N), 'both')
check('trace banner-mounted then banner-exposure-end', solve('repromoting', [('banner-mounted', N), ('banner-exposure-end', N)], N), 'inbox-only')
check('domain state regression 1: inbox', solve('saving', [('save-success', N, {'revision': 1})], N, {}, 'inbox'), {'phase': 'saving', 'value': []})
check('domain state regression 2: inbox', solve('saving', [('save-success', N, {'revision': 2})], N, {'inbox': ['other']}, 'inbox'), {'phase': 'both', 'value': ['other', 'n']})
check('domain state regression 3: inbox', solve('both', [('banner-exposure-end', N, {})], N, {'inbox': ['n']}, 'inbox'), {'phase': 'inbox-only', 'value': ['n']})
check('domain state regression 4: banner', solve('both', [('banner-exposure-end', N, {})], N, {'inbox': ['n']}, 'banner'), {'phase': 'inbox-only', 'value': False})
check('domain state regression 5: banner', solve('saving-without-banner', [('save-failure', N, {})], N, {'banner': False}, 'banner'), {'phase': 'recovery-banner', 'value': True})
check('domain state regression 6: banner', solve('saving-without-banner', [('save-success', N, {})], N, {'banner': False}, 'banner'), {'phase': 'inbox-only', 'value': False})
check('domain state regression 7: banner', solve('banner', [('retain-in-inbox', N, {}), ('banner-exposure-end', N, {}), ('save-success', N, {})], N, {}, 'banner'), {'phase': 'inbox-only', 'value': False})
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| banner / retain-in-inbox | saving | saving | Passed |
| saving / save-success | both | both | Passed |
| saving / save-failure | save-error | save-error | Passed |
| both / banner-exposure-end | inbox-only | inbox-only | Passed |
| save-error / retry-retention | saving | saving | Passed |
| saving / banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| saving-without-banner / save-success | inbox-only | inbox-only | Passed |
| saving-without-banner / save-failure | recovery-banner | recovery-banner | Passed |
| inbox-only / show-banner-again | repromoting | repromoting | Passed |
| repromoting / banner-mounted | both | both | Passed |
| older notification incarnation | banner | banner | Passed |
| future notification incarnation | banner | banner | Passed |
| unknown event is inert | banner | banner | Passed |
| empty delivery batch | banner | banner | Passed |
| N stale deliveries before current delivery | saving | saving | Passed |
| trace retain-in-inbox then save-success | both | both | Passed |
| trace retain-in-inbox then save-failure | save-error | save-error | Passed |
| trace retain-in-inbox then banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| trace save-success then banner-exposure-end | inbox-only | inbox-only | Passed |
| trace save-failure then retry-retention | saving | saving | Passed |
| trace banner-exposure-end then show-banner-again | repromoting | repromoting | Passed |
| trace retry-retention then save-success | both | both | Passed |
| trace retry-retention then save-failure | save-error | save-error | Passed |
| trace retry-retention then banner-exposure-end | saving-without-banner | saving-without-banner | Passed |
| trace banner-exposure-end then save-success | inbox-only | inbox-only | Passed |
| trace banner-exposure-end then save-failure | recovery-banner | recovery-banner | Passed |
| trace save-success then show-banner-again | repromoting | repromoting | Passed |
| trace show-banner-again then banner-mounted | both | both | Passed |
| trace banner-mounted then banner-exposure-end | inbox-only | inbox-only | Passed |
| domain state regression 1: inbox | {'phase': 'saving', 'value': []} | {'phase': 'saving', 'value': []} | Passed |
| domain state regression 2: inbox | {'phase': 'both', 'value': ['other', 'n']} | {'phase': 'both', 'value': ['other', 'n']} | Passed |
| domain state regression 3: inbox | {'phase': 'inbox-only', 'value': ['n']} | {'phase': 'inbox-only', 'value': ['n']} | Passed |
| domain state regression 4: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
| domain state regression 5: banner | {'phase': 'recovery-banner', 'value': True} | {'phase': 'recovery-banner', 'value': True} | Passed |
| domain state regression 6: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
| domain state regression 7: banner | {'phase': 'inbox-only', 'value': False} | {'phase': 'inbox-only', 'value': False} | Passed |
SHA-256 / 4f191d03be26b507cfac945ebf5c759da0d7f67ccce099c8d24d9db4e1576db1
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 2026-09-29T14:42:32.311699+00:00.
Case digest / be3041c006deb91e935987a8986488876baabbb186cc36f8b17630521aeb58ce