FA-100246 / Dataset deduplication grouping / Open access
Dataset deduplication: canonically equivalent text receives separate keys · case 01
canonically equivalent text receives separate keys.
ROOT CAUSE
The key compares code-point sequences without canonical normalization.
THE FAILURE
The key compares code-point sequences without canonical normalization.
Unsuccessful approach: Case-folding alone does not compose canonically equivalent sequences.
Case contract
Return the number of distinct NFC-normalized strings; case remains significant.
Why this case matters
This deterministic toy operation makes one dataset equivalence or representative rule explicit.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
import unicodedata
N = 1
observations = []
def solve(values):
return len(set(values))
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('composed form',solve(['é','e\u0301']),1)
check('case remains distinct',solve(['A','a']),2)
check('empty',solve([]),0)
check('same repeated',solve(['x']*N),1)
check('different accents',solve(['é','ê']),2)
check('normalized alongside plain',solve(['e','e\u0301']),2)
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 |
|---|---|---|---|
| composed form | 2 | 1 | Failed |
| case remains distinct | 2 | 2 | Passed |
| empty | 0 | 0 | Passed |
| same repeated | 1 | 1 | Passed |
| different accents | 2 | 2 | Passed |
| normalized alongside plain | 2 | 2 | Passed |
SHA-256 / 9068b12ffbd8099574c64b8970437de272c7515e216aa6b4309e2b17d1aee05b
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
import unicodedata
N = 1
observations = []
def solve(values):
return len({s.casefold() for s in values})
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('composed form',solve(['é','e\u0301']),1)
check('case remains distinct',solve(['A','a']),2)
check('empty',solve([]),0)
check('same repeated',solve(['x']*N),1)
check('different accents',solve(['é','ê']),2)
check('normalized alongside plain',solve(['e','e\u0301']),2)
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 |
|---|---|---|---|
| composed form | 2 | 1 | Failed |
| case remains distinct | 1 | 2 | Failed |
| empty | 0 | 0 | Passed |
| same repeated | 1 | 1 | Passed |
| different accents | 2 | 2 | Passed |
| normalized alongside plain | 2 | 2 | Passed |
SHA-256 / 3e5f1e414658898584c82a66fedb2d9bb08e8753ae62ef81892d5ac1048cad58
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.
Sign in to the archive ↗Verification & scope
Inputs are small in-memory fixtures with the stated contract; results do not claim production deduplication quality. 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 2026-09-30T16:48:33.560779+00:00.
Case digest / b8b8e051122e5f6951320995505c8ae364a38e6d05e7db84b41984a025c3065c