{"abstract":"Zip truncation loses the longer source tail.","category":"Audio channel mixing","checks":4,"contract":"Mix two mono arrays into the longer duration, treating samples beyond either source end as zero; no saturation.","contract_signature":"left, right","evaluation_group":"xaud-mix-pad-shorter-source","failed_approach":"Using only the first source length still loses a longer second source.","family":"xaud-mix-pad-shorter-source","id":"FA-10891","implementations":{"attempt":{"sha256":"611fb7535a87a091b48ad79b63a4589d79ff182b22b5461cc1cea3259a0f5004","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(left, right):\n    return [left[i]+(right[i] if i<len(right) else 0) for i in range(len(left))]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([1, 2, 3], [4])),[5, 2, 3])\ncheck('fixture 2',solve(*([1], [2, 3])),[3, 3])\ncheck('fixture 3',solve(*([], [1])),[1])\ncheck('fixture 4',solve(*([], [])),[])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"9d36ee529ed71a7b1c71ad7f0ff451cb11695e1d376555fc117d2549368454ec","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(left, right):\n    return [a+b for a,b in zip(left,right)]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([1, 2, 3], [4])),[5, 2, 3])\ncheck('fixture 2',solve(*([1], [2, 3])),[3, 3])\ncheck('fixture 3',solve(*([], [1])),[1])\ncheck('fixture 4',solve(*([], [])),[])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":" 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xaud-mix-pad-shorter-source","generated_at":"2026-09-29T14:38:43.149970+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A pure Python local audio pipeline stage with explicit sample formats and frame conventions; no real-time device or signal-spectrum claims.","root_cause":"Zip truncation loses the longer source tail.","sha256":"92c9916248c942af6539800a4ca9ca014b5f42c4f3f4af57b58c506b8d8c2d0f","title":"Mix pad shorter source · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":40.586,"exit_code":1,"observations":[{"actual":[5,2,3],"check":"fixture 1","expected":[5,2,3],"passed":true},{"actual":[3],"check":"fixture 2","expected":[3,3],"passed":false},{"actual":[],"check":"fixture 3","expected":[1],"passed":false},{"actual":[],"check":"fixture 4","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [5, 2, 3], \"expected\": [5, 2, 3], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [3], \"expected\": [3, 3], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.285,"exit_code":1,"observations":[{"actual":[5],"check":"fixture 1","expected":[5,2,3],"passed":false},{"actual":[3],"check":"fixture 2","expected":[3,3],"passed":false},{"actual":[],"check":"fixture 3","expected":[1],"passed":false},{"actual":[],"check":"fixture 4","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [5], \"expected\": [5, 2, 3], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [3], \"expected\": [3, 3], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}