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FA-17956 / Time representation / Open access

Timestamp intersection starts before the later bucket · case 01

The decoded time state disagrees with the explicit regression oracle for low.

Verified by executionVariant 1 · 11 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Timestamp intersection starts before the later bucket.

THE FAILURE

Timestamp intersection starts before the later bucket.

Unsuccessful approach: The partial correction still substitutes r['a'] at the same fault site.

Case contract

A timestamp rounded down to resolution q represents half-open [stamp,stamp+q). Preserve domain tag; q positive. Comparing two buckets yields exact intersection and possible/definite-before relations, equality of represented sets and union envelope. Query membership is half-open. This model handles precision buckets, not point timestamps.

Why this case matters

Clock transfer and timestamp consumers require preserved coordinate, phase, validity and elapsed-time semantics.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from fractions import Fraction
N = 1
observations = []
def solve(r):
    a_end = r['a'] + r['qa']
    b_end = r['b'] + r['qb']
    compatible = r['domain_a'] == r['domain_b']
    low = min(r['a'],r['b'])
    high = min(a_end,b_end)
    overlap = compatible and low < high
    definite_before = compatible and a_end <= r['b']
    possible_before = compatible and r['a'] < b_end
    equal = compatible and r['a'] == r['b'] and r['qa'] == r['qb']
    contains = r['a'] <= r['query'] < a_end
    return [None if not overlap else [low,high],definite_before,possible_before,equal,contains, None if not compatible else [min(r['a'],r['b']),max(a_end,b_end)]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'a': 10, 'qa': 10, 'b': 15, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}), [[15, 20], False, True, False, True, [10, 35]])
check('fixture 2', solve({'a': 10, 'qa': 10, 'b': 20, 'qb': 2, 'query': 20, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 22]])
check('fixture 3', solve({'a': 10, 'qa': 10, 'b': 10, 'qb': 2, 'query': 15, 'domain_a': 'utc', 'domain_b': 'utc'}), [[10, 12], False, True, False, True, [10, 20]])
check('fixture 4', solve({'a': 20, 'qa': 2, 'b': 10, 'qb': 10, 'query': 21, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [10, 22]])
check('fixture 5', solve({'a': 0, 'qa': 1, 'b': 0, 'qb': 1, 'query': 0, 'domain_a': 'mono', 'domain_b': 'mono'}), [[0, 1], False, True, True, True, [0, 1]])
check('fixture 6', solve({'a': 0, 'qa': 10, 'b': 2, 'qb': 3, 'query': 2, 'domain_a': 'a', 'domain_b': 'b'}), [None, False, False, False, True, None])
check('fixture 7', solve({'a': -10, 'qa': 5, 'b': -8, 'qb': 1, 'query': -5, 'domain_a': 'utc', 'domain_b': 'utc'}), [[-8, -7], False, True, False, False, [-10, -5]])
check('fixture 8', solve({'a': 0, 'qa': 3, 'b': 2, 'qb': 1, 'query': 1, 'domain_a': 'utc', 'domain_b': 'utc'}), [[2, 3], False, True, False, True, [0, 3]])
check('fixture 9', solve({'a': 10, 'qa': 1, 'b': 20, 'qb': 1, 'query': 11, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 21]])
check('fixture 10', solve({'a': 0, 'qa': 1, 'b': -1, 'qb': 1, 'query': 0, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [-1, 1]])
variant = [({'a': 10, 'qa': 10, 'b': 16, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[16, 20], False, True, False, True, [10, 36]]), ({'a': 10, 'qa': 10, 'b': 17, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[17, 20], False, True, False, True, [10, 37]]), ({'a': 10, 'qa': 10, 'b': 18, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[18, 20], False, True, False, True, [10, 38]]), ({'a': 10, 'qa': 10, 'b': 19, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[19, 20], False, True, False, True, [10, 39]]), ({'a': 10, 'qa': 10, 'b': 20, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [None, True, True, False, True, [10, 40]])]
check("variant capture", solve(variant[N-1][0]), variant[N-1][1])
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
fixture 1[[10, 20], False, True, False, True, [10, 35]][[15, 20], False, True, False, True, [10, 35]]Failed
fixture 2[[10, 20], True, True, False, False, [10, 22]][None, True, True, False, False, [10, 22]]Failed
fixture 3[[10, 12], False, True, False, True, [10, 20]][[10, 12], False, True, False, True, [10, 20]]Passed
fixture 4[[10, 20], False, False, False, True, [10, 22]][None, False, False, False, True, [10, 22]]Failed
fixture 5[[0, 1], False, True, True, True, [0, 1]][[0, 1], False, True, True, True, [0, 1]]Passed
fixture 6[None, False, False, False, True, None][None, False, False, False, True, None]Passed
fixture 7[[-10, -7], False, True, False, False, [-10, -5]][[-8, -7], False, True, False, False, [-10, -5]]Failed
fixture 8[[0, 3], False, True, False, True, [0, 3]][[2, 3], False, True, False, True, [0, 3]]Failed
fixture 9[[10, 11], True, True, False, False, [10, 21]][None, True, True, False, False, [10, 21]]Failed
fixture 10[[-1, 0], False, False, False, True, [-1, 1]][None, False, False, False, True, [-1, 1]]Failed
variant capture[[10, 20], False, True, False, True, [10, 36]][[16, 20], False, True, False, True, [10, 36]]Failed

SHA-256 / 01500ee59c2ab47b3a8edd958bbd1d612580c8e9945a0f528445e848a5acaa03

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from fractions import Fraction
N = 1
observations = []
def solve(r):
    a_end = r['a'] + r['qa']
    b_end = r['b'] + r['qb']
    compatible = r['domain_a'] == r['domain_b']
    low = r['a']
    high = min(a_end,b_end)
    overlap = compatible and low < high
    definite_before = compatible and a_end <= r['b']
    possible_before = compatible and r['a'] < b_end
    equal = compatible and r['a'] == r['b'] and r['qa'] == r['qb']
    contains = r['a'] <= r['query'] < a_end
    return [None if not overlap else [low,high],definite_before,possible_before,equal,contains, None if not compatible else [min(r['a'],r['b']),max(a_end,b_end)]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'a': 10, 'qa': 10, 'b': 15, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}), [[15, 20], False, True, False, True, [10, 35]])
check('fixture 2', solve({'a': 10, 'qa': 10, 'b': 20, 'qb': 2, 'query': 20, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 22]])
check('fixture 3', solve({'a': 10, 'qa': 10, 'b': 10, 'qb': 2, 'query': 15, 'domain_a': 'utc', 'domain_b': 'utc'}), [[10, 12], False, True, False, True, [10, 20]])
check('fixture 4', solve({'a': 20, 'qa': 2, 'b': 10, 'qb': 10, 'query': 21, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [10, 22]])
check('fixture 5', solve({'a': 0, 'qa': 1, 'b': 0, 'qb': 1, 'query': 0, 'domain_a': 'mono', 'domain_b': 'mono'}), [[0, 1], False, True, True, True, [0, 1]])
check('fixture 6', solve({'a': 0, 'qa': 10, 'b': 2, 'qb': 3, 'query': 2, 'domain_a': 'a', 'domain_b': 'b'}), [None, False, False, False, True, None])
check('fixture 7', solve({'a': -10, 'qa': 5, 'b': -8, 'qb': 1, 'query': -5, 'domain_a': 'utc', 'domain_b': 'utc'}), [[-8, -7], False, True, False, False, [-10, -5]])
check('fixture 8', solve({'a': 0, 'qa': 3, 'b': 2, 'qb': 1, 'query': 1, 'domain_a': 'utc', 'domain_b': 'utc'}), [[2, 3], False, True, False, True, [0, 3]])
check('fixture 9', solve({'a': 10, 'qa': 1, 'b': 20, 'qb': 1, 'query': 11, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 21]])
check('fixture 10', solve({'a': 0, 'qa': 1, 'b': -1, 'qb': 1, 'query': 0, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [-1, 1]])
variant = [({'a': 10, 'qa': 10, 'b': 16, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[16, 20], False, True, False, True, [10, 36]]), ({'a': 10, 'qa': 10, 'b': 17, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[17, 20], False, True, False, True, [10, 37]]), ({'a': 10, 'qa': 10, 'b': 18, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[18, 20], False, True, False, True, [10, 38]]), ({'a': 10, 'qa': 10, 'b': 19, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[19, 20], False, True, False, True, [10, 39]]), ({'a': 10, 'qa': 10, 'b': 20, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [None, True, True, False, True, [10, 40]])]
check("variant capture", solve(variant[N-1][0]), variant[N-1][1])
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
fixture 1[[10, 20], False, True, False, True, [10, 35]][[15, 20], False, True, False, True, [10, 35]]Failed
fixture 2[[10, 20], True, True, False, False, [10, 22]][None, True, True, False, False, [10, 22]]Failed
fixture 3[[10, 12], False, True, False, True, [10, 20]][[10, 12], False, True, False, True, [10, 20]]Passed
fixture 4[None, False, False, False, True, [10, 22]][None, False, False, False, True, [10, 22]]Passed
fixture 5[[0, 1], False, True, True, True, [0, 1]][[0, 1], False, True, True, True, [0, 1]]Passed
fixture 6[None, False, False, False, True, None][None, False, False, False, True, None]Passed
fixture 7[[-10, -7], False, True, False, False, [-10, -5]][[-8, -7], False, True, False, False, [-10, -5]]Failed
fixture 8[[0, 3], False, True, False, True, [0, 3]][[2, 3], False, True, False, True, [0, 3]]Failed
fixture 9[[10, 11], True, True, False, False, [10, 21]][None, True, True, False, False, [10, 21]]Failed
fixture 10[None, False, False, False, True, [-1, 1]][None, False, False, False, True, [-1, 1]]Passed
variant capture[[10, 20], False, True, False, True, [10, 36]][[16, 20], False, True, False, True, [10, 36]]Failed

SHA-256 / 97f84867afddfc8bb6325630a52123a2594a1a7eccccfbf90fa6a548deaed2be

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 11 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.

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Verification & scope

Deterministic integer reference model with stipulated units and policies; not a complete clock, wire standard or platform implementation. 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 2026-09-29T14:39:53.072209+00:00.

Case digest / 99168432e875a8530f071fe7c0c0dc6e325be60c48ed028f59141c4165c829ae