FA-99691 / Chunk citation alignment / Open access

The last cited source replaces a higher-priority source · case 01

The last cited source replaces a higher-priority source.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Source precedence is inferred from list order rather than the declared rank.

THE FAILURE

Source precedence is inferred from list order rather than the declared rank.

Unsuccessful approach: Sorting by rank alone makes tied source choice depend on input order.

Case contract

Rows [source_id,rank]; return source ID of lowest rank, then lexical ID; empty input returns None.

Why this case matters

A deterministic citation bookkeeping model isolates source attribution from rendering and retrieval.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(sources):
    return sources[-1][0] if sources else None
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('rank wins',solve([['b',2],['a',1]]),'a')
check('tie lexical',solve([['z',1],['a',1]]),'a')
check('empty',solve([]),None)
check('single',solve([['q',N]]),'q')
check('negative rank',solve([['x',0],['y',-1]]),'y')
check('input reversal',solve([['a',1],['z',1]]),'a')
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
rank wins	`a`	`a`	Passed
tie lexical	`a`	`a`	Passed
empty	`None`	`None`	Passed
single	`q`	`q`	Passed
negative rank	`y`	`y`	Passed
input reversal	`z`	`a`	Failed

SHA-256 / 88ec935d7e96d16fd91916241e1a15a9402a7c8da7d4eb899208c61717710eb1

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(sources):
    return min(sources,key=lambda x:x[1])[0] if sources else None
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('rank wins',solve([['b',2],['a',1]]),'a')
check('tie lexical',solve([['z',1],['a',1]]),'a')
check('empty',solve([]),None)
check('single',solve([['q',N]]),'q')
check('negative rank',solve([['x',0],['y',-1]]),'y')
check('input reversal',solve([['a',1],['z',1]]),'a')
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
rank wins	`a`	`a`	Passed
tie lexical	`z`	`a`	Failed
empty	`None`	`None`	Passed
single	`q`	`q`	Passed
negative rank	`y`	`y`	Passed
input reversal	`a`	`a`	Passed

SHA-256 / bf3e79b17119b47ac5ff0c1d792a7274ffdde3db927cfa96cef8895904dca3c2

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 6 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.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Verification & scope

Inputs are small integer offsets and identifiers under the stated toy contract; this does not define a document format or production citation API. 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 2026-09-30T16:48:27.159125+00:00.

Case digest / a733240fe6526108ae17c43e50b6eaae1b9150f90c247edf1c97190e02b0f3d1