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FA-21706 / Assistive announcements / Open access

Collection count is based on last item index · case 01

The announcement trace violates the stated list-change-narration contract.

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

ROOT CAUSE

Fault site: elif op=='count': out.append(['count',len(items)]) is implemented as elif op=='count': out.append(['count',len(items)-1])

VERIFIED REPAIR

Restore the stated transition: elif op=='count': out.append(['count',len(items)])

Unsuccessful approach: The attempted repair substitutes elif op=='count': out.append(['count',len(items)+1]) and still violates a regression oracle.

Case contract

An ordered collection maps unique item IDs to spoken labels. Add inserts at clamped zero-based position; existing ID updates label without moving. Remove announces old one-based position. Move removes then inserts at clamped destination and announces old/new positions. Rename announces old/new labels. Begin silences individual cues while accumulating cue count; end announces only count and clears batching. Reset clears list with no cue. Count command reports current cardinality. Return cues and ordered [id,label].

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):
    items=[]; batching=False; changes=0; out=[]
    for e in events:
        op=e[0]; cue=None
        index=next((i for i,x in enumerate(items) if len(e)>1 and x[0]==e[1]),None)
        if op=='begin': batching=True; changes=0
        elif op=='end':
            if batching and changes: out.append(['changes',changes])
            batching=False; changes=0
        elif op=='reset': items=[]
        elif op=='count': out.append(['count',len(items)-1])
        elif op=='add':
            if index is not None: items[index][1]=e[2]
            else:
                position=max(0,min(len(items),e[3])); items.insert(position,[e[1],e[2]])
                cue=['added',e[2],position+1]
        elif index is not None:
            if op=='remove':
                item=items.pop(index); cue=['removed',item[1],index+1]
            elif op=='rename': cue=['renamed',items[index][1],e[2]]; items[index][1]=e[2]
            elif op=='move':
                item=items.pop(index); position=max(0,min(len(items),e[2])); items.insert(position,item)
                cue=['moved',item[1],index+1,position+1]
        if cue is not None:
            if batching: changes+=1
            else: out.append(cue)
    return [out,items,batching,changes]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = ["[['add','a','Alpha'*N,0],['add','b','Beta',0],['add','c','Gamma',1],['count'],['remove','c']]", "[['add','a','Old',0],['add','a','New'*N,4],['rename','a','Latest']]", "[['add','a','A'*N,0],['add','b','B',1],['add','c','C',2],['move','a',99],['move','c',0]]", "[['begin'],['add','a','A'*N,0],['add','b','B',1],['end'],['begin'],['end']]", "[['add','a','A'*N,0],['reset'],['count']]", "[['remove','missing'],['move','missing',N],['end']]", '[]']
expected = {1: [[[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0], [[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0], [[['added', 'A', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 2: [[[['added', 'AlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AA']], False, 0], [[['changes', 2]], [['a', 'AA'], ['b', 'B']], False, 0], [[['added', 'AA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 3: [[[['added', 'AlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAA']], False, 0], [[['changes', 2]], [['a', 'AAA'], ['b', 'B']], False, 0], [[['added', 'AAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 4: [[[['added', 'AlphaAlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAAA']], False, 0], [[['changes', 2]], [['a', 'AAAA'], ['b', 'B']], False, 0], [[['added', 'AAAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 5: [[[['added', 'AlphaAlphaAlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAAAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAAAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAAAA']], False, 0], [[['changes', 2]], [['a', 'AAAAA'], ['b', 'B']], False, 0], [[['added', 'AAAAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]]}[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[[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 2], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0][[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0]Failed
trace-2[[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0][[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0]Passed
trace-3[[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0][[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0]Passed
trace-4[[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0][[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0]Passed
trace-5[[['added', 'A', 1], ['count', -1]], [], False, 0][[['added', 'A', 1], ['count', 0]], [], False, 0]Failed
trace-6[[], [], False, 0][[], [], False, 0]Passed
trace-7[[], [], False, 0][[], [], False, 0]Passed

SHA-256 / 6f00bc218faaccfb6855ea5c0249e50a5269fd9bec7bf4789efc51680c35db56

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(events):
    items=[]; batching=False; changes=0; out=[]
    for e in events:
        op=e[0]; cue=None
        index=next((i for i,x in enumerate(items) if len(e)>1 and x[0]==e[1]),None)
        if op=='begin': batching=True; changes=0
        elif op=='end':
            if batching and changes: out.append(['changes',changes])
            batching=False; changes=0
        elif op=='reset': items=[]
        elif op=='count': out.append(['count',len(items)+1])
        elif op=='add':
            if index is not None: items[index][1]=e[2]
            else:
                position=max(0,min(len(items),e[3])); items.insert(position,[e[1],e[2]])
                cue=['added',e[2],position+1]
        elif index is not None:
            if op=='remove':
                item=items.pop(index); cue=['removed',item[1],index+1]
            elif op=='rename': cue=['renamed',items[index][1],e[2]]; items[index][1]=e[2]
            elif op=='move':
                item=items.pop(index); position=max(0,min(len(items),e[2])); items.insert(position,item)
                cue=['moved',item[1],index+1,position+1]
        if cue is not None:
            if batching: changes+=1
            else: out.append(cue)
    return [out,items,batching,changes]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = ["[['add','a','Alpha'*N,0],['add','b','Beta',0],['add','c','Gamma',1],['count'],['remove','c']]", "[['add','a','Old',0],['add','a','New'*N,4],['rename','a','Latest']]", "[['add','a','A'*N,0],['add','b','B',1],['add','c','C',2],['move','a',99],['move','c',0]]", "[['begin'],['add','a','A'*N,0],['add','b','B',1],['end'],['begin'],['end']]", "[['add','a','A'*N,0],['reset'],['count']]", "[['remove','missing'],['move','missing',N],['end']]", '[]']
expected = {1: [[[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0], [[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0], [[['added', 'A', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 2: [[[['added', 'AlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AA']], False, 0], [[['changes', 2]], [['a', 'AA'], ['b', 'B']], False, 0], [[['added', 'AA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 3: [[[['added', 'AlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAA']], False, 0], [[['changes', 2]], [['a', 'AAA'], ['b', 'B']], False, 0], [[['added', 'AAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 4: [[[['added', 'AlphaAlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAAA']], False, 0], [[['changes', 2]], [['a', 'AAAA'], ['b', 'B']], False, 0], [[['added', 'AAAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 5: [[[['added', 'AlphaAlphaAlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAAAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAAAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAAAA']], False, 0], [[['changes', 2]], [['a', 'AAAAA'], ['b', 'B']], False, 0], [[['added', 'AAAAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]]}[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[[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 4], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0][[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0]Failed
trace-2[[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0][[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0]Passed
trace-3[[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0][[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0]Passed
trace-4[[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0][[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0]Passed
trace-5[[['added', 'A', 1], ['count', 1]], [], False, 0][[['added', 'A', 1], ['count', 0]], [], False, 0]Failed
trace-6[[], [], False, 0][[], [], False, 0]Passed
trace-7[[], [], False, 0][[], [], False, 0]Passed

SHA-256 / 47ddf9ad48bcf388d1cc08b76ae292b109bd8d691af851aee16d89375c6d85ac

3 / The verified repair

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

N = 1
observations = []
def solve(events):
    items=[]; batching=False; changes=0; out=[]
    for e in events:
        op=e[0]; cue=None
        index=next((i for i,x in enumerate(items) if len(e)>1 and x[0]==e[1]),None)
        if op=='begin': batching=True; changes=0
        elif op=='end':
            if batching and changes: out.append(['changes',changes])
            batching=False; changes=0
        elif op=='reset': items=[]
        elif op=='count': out.append(['count',len(items)])
        elif op=='add':
            if index is not None: items[index][1]=e[2]
            else:
                position=max(0,min(len(items),e[3])); items.insert(position,[e[1],e[2]])
                cue=['added',e[2],position+1]
        elif index is not None:
            if op=='remove':
                item=items.pop(index); cue=['removed',item[1],index+1]
            elif op=='rename': cue=['renamed',items[index][1],e[2]]; items[index][1]=e[2]
            elif op=='move':
                item=items.pop(index); position=max(0,min(len(items),e[2])); items.insert(position,item)
                cue=['moved',item[1],index+1,position+1]
        if cue is not None:
            if batching: changes+=1
            else: out.append(cue)
    return [out,items,batching,changes]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = ["[['add','a','Alpha'*N,0],['add','b','Beta',0],['add','c','Gamma',1],['count'],['remove','c']]", "[['add','a','Old',0],['add','a','New'*N,4],['rename','a','Latest']]", "[['add','a','A'*N,0],['add','b','B',1],['add','c','C',2],['move','a',99],['move','c',0]]", "[['begin'],['add','a','A'*N,0],['add','b','B',1],['end'],['begin'],['end']]", "[['add','a','A'*N,0],['reset'],['count']]", "[['remove','missing'],['move','missing',N],['end']]", '[]']
expected = {1: [[[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0], [[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0], [[['added', 'A', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 2: [[[['added', 'AlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AA']], False, 0], [[['changes', 2]], [['a', 'AA'], ['b', 'B']], False, 0], [[['added', 'AA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 3: [[[['added', 'AlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAA']], False, 0], [[['changes', 2]], [['a', 'AAA'], ['b', 'B']], False, 0], [[['added', 'AAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 4: [[[['added', 'AlphaAlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAAA']], False, 0], [[['changes', 2]], [['a', 'AAAA'], ['b', 'B']], False, 0], [[['added', 'AAAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]], 5: [[[['added', 'AlphaAlphaAlphaAlphaAlpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'AlphaAlphaAlphaAlphaAlpha']], False, 0], [[['added', 'Old', 1], ['renamed', 'NewNewNewNewNew', 'Latest']], [['a', 'Latest']], False, 0], [[['added', 'AAAAA', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'AAAAA', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'AAAAA']], False, 0], [[['changes', 2]], [['a', 'AAAAA'], ['b', 'B']], False, 0], [[['added', 'AAAAA', 1], ['count', 0]], [], False, 0], [[], [], False, 0], [[], [], False, 0]]}[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[[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0][[['added', 'Alpha', 1], ['added', 'Beta', 1], ['added', 'Gamma', 2], ['count', 3], ['removed', 'Gamma', 2]], [['b', 'Beta'], ['a', 'Alpha']], False, 0]Passed
trace-2[[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0][[['added', 'Old', 1], ['renamed', 'New', 'Latest']], [['a', 'Latest']], False, 0]Passed
trace-3[[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0][[['added', 'A', 1], ['added', 'B', 2], ['added', 'C', 3], ['moved', 'A', 1, 3], ['moved', 'C', 2, 1]], [['c', 'C'], ['b', 'B'], ['a', 'A']], False, 0]Passed
trace-4[[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0][[['changes', 2]], [['a', 'A'], ['b', 'B']], False, 0]Passed
trace-5[[['added', 'A', 1], ['count', 0]], [], False, 0][[['added', 'A', 1], ['count', 0]], [], False, 0]Passed
trace-6[[], [], False, 0][[], [], False, 0]Passed
trace-7[[], [], False, 0][[], [], False, 0]Passed

SHA-256 / 206d60a0fed2b5f69ecb70b492894accdfc4c5309f278aa5475be18275c0e9b6

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 2026-09-29T14:40:31.373334+00:00.

Case digest / 1c6daac3a68b349a25f54f6ee3cd57b2de80e7932bdb2c6ad17fc6714fe6ab58