FAILURE MAP
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FA-11006 / Audio playback scheduling / Open access

Audio block partition keeps final tail · case 01

Only complete processing blocks are retained, dropping the final audio tail.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Only complete processing blocks are retained, dropping the final audio tail.

VERIFIED REPAIR

Apply the explicit PCM/playback contract: Partition a finite mono stream into disjoint nonempty blocks of positive size at least two, retaining a short final tail.

Unsuccessful approach: Advancing by one fewer sample duplicates overlap between successive blocks.

Case contract

Partition a finite mono stream into disjoint nonempty blocks of positive size at least two, retaining a short final tail.

Why this case matters

A pure Python local audio pipeline stage with explicit sample formats and frame conventions; no real-time device or signal-spectrum claims.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(samples, size):
    return [samples[i:i+size] for i in range(0,len(samples)-size+1,size)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1',solve(*([1, 2, 3, 4, 5], 2)),[[1, 2], [3, 4], [5]])
check('fixture 2',solve(*([1], 2)),[[1]])
check('fixture 3',solve(*([], 2)),[])
check('fixture 4',solve(*([1, 2, 3], 3)),[[1, 2, 3]])
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[[1, 2], [3, 4]][[1, 2], [3, 4], [5]]Failed
fixture 2[][[1]]Failed
fixture 3[][]Passed
fixture 4[[1, 2, 3]][[1, 2, 3]]Passed

SHA-256 / f96fcd7eac5d8c685f454b7e4912677044f1fdeaca2ef1aa2b8989c704918d39

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(samples, size):
    return [samples[i:i+size] for i in range(0,len(samples),size-1)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1',solve(*([1, 2, 3, 4, 5], 2)),[[1, 2], [3, 4], [5]])
check('fixture 2',solve(*([1], 2)),[[1]])
check('fixture 3',solve(*([], 2)),[])
check('fixture 4',solve(*([1, 2, 3], 3)),[[1, 2, 3]])
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[[1, 2], [2, 3], [3, 4], [4, 5], [5]][[1, 2], [3, 4], [5]]Failed
fixture 2[[1]][[1]]Passed
fixture 3[][]Passed
fixture 4[[1, 2, 3], [3]][[1, 2, 3]]Failed

SHA-256 / e85035cc0675b8c11cc4057cf2ca623414c9e149ee702f443219e01544dd7134

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(samples, size):
    return [samples[i:i+size] for i in range(0,len(samples),size)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1',solve(*([1, 2, 3, 4, 5], 2)),[[1, 2], [3, 4], [5]])
check('fixture 2',solve(*([1], 2)),[[1]])
check('fixture 3',solve(*([], 2)),[])
check('fixture 4',solve(*([1, 2, 3], 3)),[[1, 2, 3]])
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[[1, 2], [3, 4], [5]][[1, 2], [3, 4], [5]]Passed
fixture 2[[1]][[1]]Passed
fixture 3[][]Passed
fixture 4[[1, 2, 3]][[1, 2, 3]]Passed

SHA-256 / 37594431c62bf3b0325173c570d55df632b70997871e22c1f1156280224c1430

Verification & scope

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 2026-09-29T14:38:44.173215+00:00.

Case digest / 3b8dfe4a7b60ee73a4ec843700cb0bc88ac7945c3f41f3f866463192da76ba43