FAILURE MAP
← Case archive

FA-33026 / Menu interactions / Open access

Empty overflow popup leaves an unnecessary menu trigger · case 01

Empty overflow popup leaves an unnecessary menu trigger.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The overflow-menu model applies `True` at its trigger-visible operation instead of the stipulated transformation.

VERIFIED REPAIR

Apply `bool(p['overflow'])` at trigger-visible.

Unsuccessful approach: The attempted repair `p['capacity']<=len(p['main'])` still violates the trigger-visible oracle.

Case contract

A menu overflow container reserves its own trigger, preserves complete groups, and restores source order when room returns.

Why this case matters

Cascading and context menus require coherent command and session state as content changes.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
import unicodedata
N = 1
observations = []
def solve(action, p):
    if action == 'reserve-trigger':
        return p['capacity']-p['trigger']
    if action == 'prefix-fit':
        return next((i for i in range(len(p['widths'])+1) if sum(p['widths'][:i+1])>p['capacity']),len(p['widths']))
    if action == 'suffix':
        return p['items'][p['fit']:]
    if action == 'group-atomic':
        return [g for g in p['groups'] if g['width']<=p['remaining']]
    if action == 'restore':
        return sorted(p,key=lambda x:x['source'])
    if action == 'trigger-visible':
        return True
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('reserve-trigger contract', solve('reserve-trigger', {'capacity':N+10,'trigger':3}), N+7)
check('prefix-fit contract', solve('prefix-fit', {'widths':[N+1,N+1,N+1],'capacity':2*(N+1)}), 2)
check('suffix contract', solve('suffix', {'items':list(range(N+4)),'fit':2}), list(range(2,N+4)))
check('group-atomic contract', solve('group-atomic', {'groups':[{'width':N+2,'id':'a'},{'width':N+3,'id':'b'}],'remaining':N+2}), [{'width':N+2,'id':'a'}])
check('restore contract', solve('restore', [{'source':2,'label':'a'},{'source':N-N,'label':'z'}]), [{'source':0,'label':'z'},{'source':2,'label':'a'}])
check('trigger-visible contract', solve('trigger-visible', {'overflow':[],'capacity':N,'main':list(range(N))}), False)
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
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
reserve-trigger contract88Passed
prefix-fit contract22Passed
suffix contract[2, 3, 4][2, 3, 4]Passed
group-atomic contract[{'id': 'a', 'width': 3}][{'id': 'a', 'width': 3}]Passed
restore contract[{'label': 'z', 'source': 0}, {'label': 'a', 'source': 2}][{'label': 'z', 'source': 0}, {'label': 'a', 'source': 2}]Passed
trigger-visible contractTrueFalseFailed
unknown operation{'error': 'unsupported menu operation'}{'error': 'unsupported menu operation'}Passed

SHA-256 / 1733a54ade38dd34debd9fd9b3e2512d4d04ca1a3a60beebb47e29ea27f23a84

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
import unicodedata
N = 1
observations = []
def solve(action, p):
    if action == 'reserve-trigger':
        return p['capacity']-p['trigger']
    if action == 'prefix-fit':
        return next((i for i in range(len(p['widths'])+1) if sum(p['widths'][:i+1])>p['capacity']),len(p['widths']))
    if action == 'suffix':
        return p['items'][p['fit']:]
    if action == 'group-atomic':
        return [g for g in p['groups'] if g['width']<=p['remaining']]
    if action == 'restore':
        return sorted(p,key=lambda x:x['source'])
    if action == 'trigger-visible':
        return p['capacity']<=len(p['main'])
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('reserve-trigger contract', solve('reserve-trigger', {'capacity':N+10,'trigger':3}), N+7)
check('prefix-fit contract', solve('prefix-fit', {'widths':[N+1,N+1,N+1],'capacity':2*(N+1)}), 2)
check('suffix contract', solve('suffix', {'items':list(range(N+4)),'fit':2}), list(range(2,N+4)))
check('group-atomic contract', solve('group-atomic', {'groups':[{'width':N+2,'id':'a'},{'width':N+3,'id':'b'}],'remaining':N+2}), [{'width':N+2,'id':'a'}])
check('restore contract', solve('restore', [{'source':2,'label':'a'},{'source':N-N,'label':'z'}]), [{'source':0,'label':'z'},{'source':2,'label':'a'}])
check('trigger-visible contract', solve('trigger-visible', {'overflow':[],'capacity':N,'main':list(range(N))}), False)
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
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
reserve-trigger contract88Passed
prefix-fit contract22Passed
suffix contract[2, 3, 4][2, 3, 4]Passed
group-atomic contract[{'id': 'a', 'width': 3}][{'id': 'a', 'width': 3}]Passed
restore contract[{'label': 'z', 'source': 0}, {'label': 'a', 'source': 2}][{'label': 'z', 'source': 0}, {'label': 'a', 'source': 2}]Passed
trigger-visible contractTrueFalseFailed
unknown operation{'error': 'unsupported menu operation'}{'error': 'unsupported menu operation'}Passed

SHA-256 / 7fd21889a6bb5f2767e97aa033426db4a7f824647aeb4f0ac7ed84f57172d9cf

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
import unicodedata
N = 1
observations = []
def solve(action, p):
    if action == 'reserve-trigger':
        return p['capacity']-p['trigger']
    if action == 'prefix-fit':
        return next((i for i in range(len(p['widths'])+1) if sum(p['widths'][:i+1])>p['capacity']),len(p['widths']))
    if action == 'suffix':
        return p['items'][p['fit']:]
    if action == 'group-atomic':
        return [g for g in p['groups'] if g['width']<=p['remaining']]
    if action == 'restore':
        return sorted(p,key=lambda x:x['source'])
    if action == 'trigger-visible':
        return bool(p['overflow'])
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('reserve-trigger contract', solve('reserve-trigger', {'capacity':N+10,'trigger':3}), N+7)
check('prefix-fit contract', solve('prefix-fit', {'widths':[N+1,N+1,N+1],'capacity':2*(N+1)}), 2)
check('suffix contract', solve('suffix', {'items':list(range(N+4)),'fit':2}), list(range(2,N+4)))
check('group-atomic contract', solve('group-atomic', {'groups':[{'width':N+2,'id':'a'},{'width':N+3,'id':'b'}],'remaining':N+2}), [{'width':N+2,'id':'a'}])
check('restore contract', solve('restore', [{'source':2,'label':'a'},{'source':N-N,'label':'z'}]), [{'source':0,'label':'z'},{'source':2,'label':'a'}])
check('trigger-visible contract', solve('trigger-visible', {'overflow':[],'capacity':N,'main':list(range(N))}), False)
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
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
reserve-trigger contract88Passed
prefix-fit contract22Passed
suffix contract[2, 3, 4][2, 3, 4]Passed
group-atomic contract[{'id': 'a', 'width': 3}][{'id': 'a', 'width': 3}]Passed
restore contract[{'label': 'z', 'source': 0}, {'label': 'a', 'source': 2}][{'label': 'z', 'source': 0}, {'label': 'a', 'source': 2}]Passed
trigger-visible contractFalseFalsePassed
unknown operation{'error': 'unsupported menu operation'}{'error': 'unsupported menu operation'}Passed

SHA-256 / 67a96186ab1c75343719c34406eae59dbf9a088bfe25933eab78774fe3d44424

Verification & scope

Offline supplied-valid-payload model; excludes DOM, keyboard, focus, selection, announcements and browser conformance. 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 2026-09-29T14:42:18.187961+00:00.

Case digest / c3870e941d0841eaa13ee587220301a1a6e38347cac905e68edb1f785e60525a