FA-54731 / Accessibility interaction semantics / Open access
Visual wrapping is reported as a hard text newline · case 01
Visual wrapping is reported as a hard text newline.
ROOT CAUSE
The hard break decision in the visual line query adapter violates its declared contract.
VERIFIED REPAIR
Apply the exact contract at the hard break decision: text[start:end],hard
Unsuccessful approach: The local repair substitutes text[start:end],not hard but still mishandles the regression fixtures.
Case contract
Input [text,lines,offset,affinity] lines ordered nonoverlapping [start,end,hard_break] in codepoint coordinates. Each line covers half-open text range; an offset on shared line boundary selects next line for forward affinity, previous for backward. Final document-end offset selects final line. Empty text with one empty line is valid. Return [index,start,end,text_segment,hard_break], or None for offsets outside text or gaps. Newline characters are included only if line bounds include them. No text wrapping is performed.
Why this case matters
Offline accessibility bridge model with explicit policy; useful for testing semantic API adapters independently of browser implementations.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(data):
text,lines,offset,affinity = data
if offset < 0 or offset > len(text): return None
matches = []
for i,(start,end,hard) in enumerate(lines):
inside = start <= offset < end
boundary = offset == end and (affinity == 'backward' or offset == len(text))
empty = start == end == offset and len(text) == 0
if inside or boundary or empty: matches.append(i)
if not matches: return None
index = matches[0] if affinity == 'backward' else matches[-1]
start,end,hard = lines[index]
return [index,start,end,text[start:end],True]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('contract fixture 1', solve(['A'*N+'BC',[[0,N,False],[N,N+2,True]],N,'forward'],), [1,N,N+2,'BC',True])
check('contract fixture 2', solve(['A'*N+'BC',[[0,N,False],[N,N+2,True]],N,'backward'],), [0,0,N,'A'*N,False])
check('contract fixture 3', solve(['abc',[[0,3,False]],3,'forward'],), [0,0,3,'abc',False])
check('contract fixture 4', solve(['a\nb',[[0,2,True],[2,3,False]],1,'forward'],), [0,0,2,'a\n',True])
check('contract fixture 5', solve(['abc',[[0,1,False],[2,3,False]],1,'forward'],), None)
check('contract fixture 6', solve(['abc',[[0,3,False]],-1,'backward'],), None)
check('contract fixture 7', solve(['abc',[[0,3,False]],4,'backward'],), None)
check('contract fixture 8', solve(['',[[0,0,False]],0,'forward'],), [0,0,0,'',False])
check('contract fixture 9', solve(['abc',[],0,'forward'],), None)
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 |
|---|---|---|---|
| contract fixture 1 | [1, 1, 3, 'BC', True] | [1, 1, 3, 'BC', True] | Passed |
| contract fixture 2 | [0, 0, 1, 'A', True] | [0, 0, 1, 'A', False] | Failed |
| contract fixture 3 | [0, 0, 3, 'abc', True] | [0, 0, 3, 'abc', False] | Failed |
| contract fixture 4 | [0, 0, 2, 'a\n', True] | [0, 0, 2, 'a\n', True] | Passed |
| contract fixture 5 | None | None | Passed |
| contract fixture 6 | None | None | Passed |
| contract fixture 7 | None | None | Passed |
| contract fixture 8 | [0, 0, 0, '', True] | [0, 0, 0, '', False] | Failed |
| contract fixture 9 | None | None | Passed |
SHA-256 / 1d539bad25c7cd89a19ac3fdc6ba0ffd5473fafe0d48aadeb2885597a539769f
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(data):
text,lines,offset,affinity = data
if offset < 0 or offset > len(text): return None
matches = []
for i,(start,end,hard) in enumerate(lines):
inside = start <= offset < end
boundary = offset == end and (affinity == 'backward' or offset == len(text))
empty = start == end == offset and len(text) == 0
if inside or boundary or empty: matches.append(i)
if not matches: return None
index = matches[0] if affinity == 'backward' else matches[-1]
start,end,hard = lines[index]
return [index,start,end,text[start:end],not hard]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('contract fixture 1', solve(['A'*N+'BC',[[0,N,False],[N,N+2,True]],N,'forward'],), [1,N,N+2,'BC',True])
check('contract fixture 2', solve(['A'*N+'BC',[[0,N,False],[N,N+2,True]],N,'backward'],), [0,0,N,'A'*N,False])
check('contract fixture 3', solve(['abc',[[0,3,False]],3,'forward'],), [0,0,3,'abc',False])
check('contract fixture 4', solve(['a\nb',[[0,2,True],[2,3,False]],1,'forward'],), [0,0,2,'a\n',True])
check('contract fixture 5', solve(['abc',[[0,1,False],[2,3,False]],1,'forward'],), None)
check('contract fixture 6', solve(['abc',[[0,3,False]],-1,'backward'],), None)
check('contract fixture 7', solve(['abc',[[0,3,False]],4,'backward'],), None)
check('contract fixture 8', solve(['',[[0,0,False]],0,'forward'],), [0,0,0,'',False])
check('contract fixture 9', solve(['abc',[],0,'forward'],), None)
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 |
|---|---|---|---|
| contract fixture 1 | [1, 1, 3, 'BC', False] | [1, 1, 3, 'BC', True] | Failed |
| contract fixture 2 | [0, 0, 1, 'A', True] | [0, 0, 1, 'A', False] | Failed |
| contract fixture 3 | [0, 0, 3, 'abc', True] | [0, 0, 3, 'abc', False] | Failed |
| contract fixture 4 | [0, 0, 2, 'a\n', False] | [0, 0, 2, 'a\n', True] | Failed |
| contract fixture 5 | None | None | Passed |
| contract fixture 6 | None | None | Passed |
| contract fixture 7 | None | None | Passed |
| contract fixture 8 | [0, 0, 0, '', True] | [0, 0, 0, '', False] | Failed |
| contract fixture 9 | None | None | Passed |
SHA-256 / 837b12567e9c1b07e5ed554c1bab0a6d31e1344760c6ee0bce8f4c3becc7087d
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(data):
text,lines,offset,affinity = data
if offset < 0 or offset > len(text): return None
matches = []
for i,(start,end,hard) in enumerate(lines):
inside = start <= offset < end
boundary = offset == end and (affinity == 'backward' or offset == len(text))
empty = start == end == offset and len(text) == 0
if inside or boundary or empty: matches.append(i)
if not matches: return None
index = matches[0] if affinity == 'backward' else matches[-1]
start,end,hard = lines[index]
return [index,start,end,text[start:end],hard]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('contract fixture 1', solve(['A'*N+'BC',[[0,N,False],[N,N+2,True]],N,'forward'],), [1,N,N+2,'BC',True])
check('contract fixture 2', solve(['A'*N+'BC',[[0,N,False],[N,N+2,True]],N,'backward'],), [0,0,N,'A'*N,False])
check('contract fixture 3', solve(['abc',[[0,3,False]],3,'forward'],), [0,0,3,'abc',False])
check('contract fixture 4', solve(['a\nb',[[0,2,True],[2,3,False]],1,'forward'],), [0,0,2,'a\n',True])
check('contract fixture 5', solve(['abc',[[0,1,False],[2,3,False]],1,'forward'],), None)
check('contract fixture 6', solve(['abc',[[0,3,False]],-1,'backward'],), None)
check('contract fixture 7', solve(['abc',[[0,3,False]],4,'backward'],), None)
check('contract fixture 8', solve(['',[[0,0,False]],0,'forward'],), [0,0,0,'',False])
check('contract fixture 9', solve(['abc',[],0,'forward'],), None)
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 |
|---|---|---|---|
| contract fixture 1 | [1, 1, 3, 'BC', True] | [1, 1, 3, 'BC', True] | Passed |
| contract fixture 2 | [0, 0, 1, 'A', False] | [0, 0, 1, 'A', False] | Passed |
| contract fixture 3 | [0, 0, 3, 'abc', False] | [0, 0, 3, 'abc', False] | Passed |
| contract fixture 4 | [0, 0, 2, 'a\n', True] | [0, 0, 2, 'a\n', True] | Passed |
| contract fixture 5 | None | None | Passed |
| contract fixture 6 | None | None | Passed |
| contract fixture 7 | None | None | Passed |
| contract fixture 8 | [0, 0, 0, '', False] | [0, 0, 0, '', False] | Passed |
| contract fixture 9 | None | None | Passed |
SHA-256 / 5bd3511058a4540f596756549d23920ba4477c6cd763bc2e38b206815f8b18a1
Verification & scope
Stipulated finite adapter contract, not a claim of platform accessibility or ARIA 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 2026-09-29T14:45:51.113479+00:00.
Case digest / 92c4b8ec716d095288e1603d934fb75067229655052bbec78052019326f7f6b1