FAILURE MAP
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FA-21831 / Assistive announcements / Open access

Completion is announced after only one output channel · case 01

The announcement trace violates the stated dual-channel-barrier contract.

Verified by executionVariant 1 · 9 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Fault site: if not(row[1] and row[2]): continue is implemented as if not(row[1] or row[2]): continue

THE FAILURE

Fault site: if not(row[1] and row[2]): continue is implemented as if not(row[1] or row[2]): continue

Unsuccessful approach: The attempted repair substitutes if not row[1]: continue and still violates a regression oracle.

Case contract

An announcement delivery couples speech and braille with per-message receipts. Submit creates [text,speechDone=False,brailleDone=False]. Speech and braille ACK set only their channel. Commit emits completion once only when both acknowledged and removes message. Disable-braille marks pending braille complete and affects future submissions; enable only affects future submissions. Replace text resets both receipts according to current enabled channels. Cancel drops one pending item. Report completion text, pending receipts and braille enabled.

Why this case matters

Deterministic controlled model of assistive announcement delivery.

1 / The failure

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

N = 1
observations = []
def solve(events):
    pending={}; braille=True; out=[]
    for e in events:
        if e[0]=='submit': pending[e[1]]=[e[2],False,not braille]
        elif e[0]=='disable-braille':
            braille=False
            for row in pending.values(): row[2]=True
        elif e[0]=='enable-braille': braille=True
        elif e[0]=='cancel': pending.pop(e[1],None)
        elif len(e)>1 and e[1] in pending:
            row=pending[e[1]]
            if e[0]=='speech': row[1]=True
            elif e[0]=='braille': row[2]=True
            elif e[0]=='replace': row[:]=[e[2],False,not braille]
            elif e[0]=='commit':
                if not(row[1] or row[2]): continue
                out.append(row[0])
                del pending[e[1]]
    return [out,[[k]+v for k,v in pending.items()],braille]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = ["[['submit','a','hello'*N],['speech','a'],['commit','a']]", "[['submit','a','hello'*N],['braille','a'],['commit','a']]", "[['submit','a','hello'*N],['speech','a'],['braille','a'],['submit','b','keep'],['commit','a'],['commit','a']]", "[['submit','a','old'],['speech','a'],['braille','a'],['replace','a','new'*N],['commit','a']]", "[['submit','a','pending'*N],['disable-braille'],['commit','a'],['submit','b','future'],['speech','b'],['commit','b'],['enable-braille']]", "[['disable-braille'],['submit','a','new'*N],['commit','a']]", "[['disable-braille'],['submit','a','old'],['replace','a','new'*N],['speech','a'],['commit','a']]", "[['submit','a','a'*N],['submit','b','b'],['cancel','a']]", '[]']
expected = {1: [[[], [['a', 'hello', True, False]], True], [[], [['a', 'hello', False, True]], True], [['hello'], [['b', 'keep', False, False]], True], [[], [['a', 'new', False, False]], True], [['future'], [['a', 'pending', False, True]], True], [[], [['a', 'new', False, True]], False], [['new'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 2: [[[], [['a', 'hellohello', True, False]], True], [[], [['a', 'hellohello', False, True]], True], [['hellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnew', False, False]], True], [['future'], [['a', 'pendingpending', False, True]], True], [[], [['a', 'newnew', False, True]], False], [['newnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 3: [[[], [['a', 'hellohellohello', True, False]], True], [[], [['a', 'hellohellohello', False, True]], True], [['hellohellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnewnew', False, False]], True], [['future'], [['a', 'pendingpendingpending', False, True]], True], [[], [['a', 'newnewnew', False, True]], False], [['newnewnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 4: [[[], [['a', 'hellohellohellohello', True, False]], True], [[], [['a', 'hellohellohellohello', False, True]], True], [['hellohellohellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnewnewnew', False, False]], True], [['future'], [['a', 'pendingpendingpendingpending', False, True]], True], [[], [['a', 'newnewnewnew', False, True]], False], [['newnewnewnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 5: [[[], [['a', 'hellohellohellohellohello', True, False]], True], [[], [['a', 'hellohellohellohellohello', False, True]], True], [['hellohellohellohellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnewnewnewnew', False, False]], True], [['future'], [['a', 'pendingpendingpendingpendingpending', False, True]], True], [[], [['a', 'newnewnewnewnew', False, True]], False], [['newnewnewnewnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]]}[N]
for i, expression in enumerate(fixtures):
    check("trace-"+str(i+1), solve(eval(expression)), expected[i])
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
trace-1[['hello'], [], True][[], [['a', 'hello', True, False]], True]Failed
trace-2[['hello'], [], True][[], [['a', 'hello', False, True]], True]Failed
trace-3[['hello'], [['b', 'keep', False, False]], True][['hello'], [['b', 'keep', False, False]], True]Passed
trace-4[[], [['a', 'new', False, False]], True][[], [['a', 'new', False, False]], True]Passed
trace-5[['pending', 'future'], [], True][['future'], [['a', 'pending', False, True]], True]Failed
trace-6[['new'], [], False][[], [['a', 'new', False, True]], False]Failed
trace-7[['new'], [], False][['new'], [], False]Passed
trace-8[[], [['b', 'b', False, False]], True][[], [['b', 'b', False, False]], True]Passed
trace-9[[], [], True][[], [], True]Passed

SHA-256 / 837a01d269bfcdb70ee4f516d1005e313a8461456c04ffdc8d6e691e3f7fb2a8

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(events):
    pending={}; braille=True; out=[]
    for e in events:
        if e[0]=='submit': pending[e[1]]=[e[2],False,not braille]
        elif e[0]=='disable-braille':
            braille=False
            for row in pending.values(): row[2]=True
        elif e[0]=='enable-braille': braille=True
        elif e[0]=='cancel': pending.pop(e[1],None)
        elif len(e)>1 and e[1] in pending:
            row=pending[e[1]]
            if e[0]=='speech': row[1]=True
            elif e[0]=='braille': row[2]=True
            elif e[0]=='replace': row[:]=[e[2],False,not braille]
            elif e[0]=='commit':
                if not row[1]: continue
                out.append(row[0])
                del pending[e[1]]
    return [out,[[k]+v for k,v in pending.items()],braille]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = ["[['submit','a','hello'*N],['speech','a'],['commit','a']]", "[['submit','a','hello'*N],['braille','a'],['commit','a']]", "[['submit','a','hello'*N],['speech','a'],['braille','a'],['submit','b','keep'],['commit','a'],['commit','a']]", "[['submit','a','old'],['speech','a'],['braille','a'],['replace','a','new'*N],['commit','a']]", "[['submit','a','pending'*N],['disable-braille'],['commit','a'],['submit','b','future'],['speech','b'],['commit','b'],['enable-braille']]", "[['disable-braille'],['submit','a','new'*N],['commit','a']]", "[['disable-braille'],['submit','a','old'],['replace','a','new'*N],['speech','a'],['commit','a']]", "[['submit','a','a'*N],['submit','b','b'],['cancel','a']]", '[]']
expected = {1: [[[], [['a', 'hello', True, False]], True], [[], [['a', 'hello', False, True]], True], [['hello'], [['b', 'keep', False, False]], True], [[], [['a', 'new', False, False]], True], [['future'], [['a', 'pending', False, True]], True], [[], [['a', 'new', False, True]], False], [['new'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 2: [[[], [['a', 'hellohello', True, False]], True], [[], [['a', 'hellohello', False, True]], True], [['hellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnew', False, False]], True], [['future'], [['a', 'pendingpending', False, True]], True], [[], [['a', 'newnew', False, True]], False], [['newnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 3: [[[], [['a', 'hellohellohello', True, False]], True], [[], [['a', 'hellohellohello', False, True]], True], [['hellohellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnewnew', False, False]], True], [['future'], [['a', 'pendingpendingpending', False, True]], True], [[], [['a', 'newnewnew', False, True]], False], [['newnewnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 4: [[[], [['a', 'hellohellohellohello', True, False]], True], [[], [['a', 'hellohellohellohello', False, True]], True], [['hellohellohellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnewnewnew', False, False]], True], [['future'], [['a', 'pendingpendingpendingpending', False, True]], True], [[], [['a', 'newnewnewnew', False, True]], False], [['newnewnewnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]], 5: [[[], [['a', 'hellohellohellohellohello', True, False]], True], [[], [['a', 'hellohellohellohellohello', False, True]], True], [['hellohellohellohellohello'], [['b', 'keep', False, False]], True], [[], [['a', 'newnewnewnewnew', False, False]], True], [['future'], [['a', 'pendingpendingpendingpendingpending', False, True]], True], [[], [['a', 'newnewnewnewnew', False, True]], False], [['newnewnewnewnew'], [], False], [[], [['b', 'b', False, False]], True], [[], [], True]]}[N]
for i, expression in enumerate(fixtures):
    check("trace-"+str(i+1), solve(eval(expression)), expected[i])
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
trace-1[['hello'], [], True][[], [['a', 'hello', True, False]], True]Failed
trace-2[[], [['a', 'hello', False, True]], True][[], [['a', 'hello', False, True]], True]Passed
trace-3[['hello'], [['b', 'keep', False, False]], True][['hello'], [['b', 'keep', False, False]], True]Passed
trace-4[[], [['a', 'new', False, False]], True][[], [['a', 'new', False, False]], True]Passed
trace-5[['future'], [['a', 'pending', False, True]], True][['future'], [['a', 'pending', False, True]], True]Passed
trace-6[[], [['a', 'new', False, True]], False][[], [['a', 'new', False, True]], False]Passed
trace-7[['new'], [], False][['new'], [], False]Passed
trace-8[[], [['b', 'b', False, False]], True][[], [['b', 'b', False, False]], True]Passed
trace-9[[], [], True][[], [], True]Passed

SHA-256 / 102ce38c2005e74b17f78943f773fef70fb2e39dbb13744dd30b85c2adacb12b

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 9 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.

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Verification & scope

Stipulated bounded policy, not a browser, speech engine, platform API, or standards conformance claim. 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 2026-09-29T14:40:32.592991+00:00.

Case digest / a985e675a0fd2cb3a76ad1b282fdbea7d789da5c0475586ab102b23dbbed7c16