FA-100241 / Dataset deduplication grouping / Open access
Dataset deduplication: case variants survive text-key deduplication · case 01
case variants survive text-key deduplication.
ROOT CAUSE
The comparison key preserves case despite a case-insensitive identity contract.
THE FAILURE
The comparison key preserves case despite a case-insensitive identity contract.
Unsuccessful approach: Lowercasing and case-folding differ for some Unicode strings.
Case contract
Return the number of distinct Unicode case-folded strings. Whitespace and punctuation remain 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
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('ASCII case duplicates',solve(['Row'+str(N),'row'+str(N)]),1)
check('Unicode case fold',solve(['ß','SS']),1)
check('punctuation matters',solve(['a-b','ab']),2)
check('empty list',solve([]),0)
check('single value',solve(['X']),1)
check('distinct values',solve(['a','b']),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 |
|---|---|---|---|
| ASCII case duplicates | 2 | 1 | Failed |
| Unicode case fold | 2 | 1 | Failed |
| punctuation matters | 2 | 2 | Passed |
| empty list | 0 | 0 | Passed |
| single value | 1 | 1 | Passed |
| distinct values | 2 | 2 | Passed |
SHA-256 / dc6abae5ff1b80d35d57f13b4487db346ee607f0682a3d0247afa7a1f3b5671c
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(values):
return len({s.lower() for s in values})
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('ASCII case duplicates',solve(['Row'+str(N),'row'+str(N)]),1)
check('Unicode case fold',solve(['ß','SS']),1)
check('punctuation matters',solve(['a-b','ab']),2)
check('empty list',solve([]),0)
check('single value',solve(['X']),1)
check('distinct values',solve(['a','b']),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 |
|---|---|---|---|
| ASCII case duplicates | 1 | 1 | Passed |
| Unicode case fold | 2 | 1 | Failed |
| punctuation matters | 2 | 2 | Passed |
| empty list | 0 | 0 | Passed |
| single value | 1 | 1 | Passed |
| distinct values | 2 | 2 | Passed |
SHA-256 / f32fa2802dc08c0461fc7a6887ae4d98d0e0f701dd31b5860dc9820df696936d
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 2026-09-30T16:48:33.560815+00:00.
Case digest / 8f42271a866a08ad346809d71a1f18920074870d9a909f2ecaa30b59b6ea2393