{"abstract":"Missing peers are classified as version failures.","category":"Dependency resolution","checks":8,"contract":"For each peer in declaration order, ignore missing optional peers, report missing required peers, report too-old installed peers, report too-new peers, and accept inclusive lower/exclusive upper versions.","evaluation_group":"xt-peer-validation","failed_approach":"The attempted repair substitutes (name, 'high'). Fixture 2 still yields [('a', 'high')] instead of [('a', 'missing')].","family":"xt-peer-validation-missing-class","id":"FA-9461","implementations":{"attempt":{"sha256":"53dbe0541df1fe84a4fe99a751ea52983cd232cca6687b61bf93baba02c1dfa1","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(peers, installed):\n    result = []\n    for name, low, high, optional in peers:\n        if name not in installed:\n            if not optional: result.append((name, 'high'))\n            continue\n        version = installed[name]\n        if version < low: result.append((name, 'low'))\n        elif version >= high: result.append((name, 'high'))\n    return result\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve([], {}), [])\ncheck('fixture 2', solve([('a', 1, 3, False)], {}), [('a', 'missing')])\ncheck('fixture 3', solve([('a', 1, 3, True)], {}), [])\ncheck('fixture 4', solve([('a', 1, 3, False)], {'a': 0}), [('a', 'low')])\ncheck('fixture 5', solve([('a', 1, 3, False)], {'a': 1}), [])\ncheck('fixture 6', solve([('a', 1, 3, False)], {'a': 2}), [])\ncheck('fixture 7', solve([('a', 1, 3, False)], {'a': 3}), [('a', 'high')])\ncheck('fixture 8', solve([('a', 1, 3, False)], {'a': 4}), [('a', 'high')])\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":"8f2418054e8ed6552a241ba596eecab5525224e4fa021cb80be038311a8eb474","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(peers, installed):\n    result = []\n    for name, low, high, optional in peers:\n        if name not in installed:\n            if not optional: result.append((name, 'low'))\n            continue\n        version = installed[name]\n        if version < low: result.append((name, 'low'))\n        elif version >= high: result.append((name, 'high'))\n    return result\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve([], {}), [])\ncheck('fixture 2', solve([('a', 1, 3, False)], {}), [('a', 'missing')])\ncheck('fixture 3', solve([('a', 1, 3, True)], {}), [])\ncheck('fixture 4', solve([('a', 1, 3, False)], {'a': 0}), [('a', 'low')])\ncheck('fixture 5', solve([('a', 1, 3, False)], {'a': 1}), [])\ncheck('fixture 6', solve([('a', 1, 3, False)], {'a': 2}), [])\ncheck('fixture 7', solve([('a', 1, 3, False)], {'a': 3}), [('a', 'high')])\ncheck('fixture 8', solve([('a', 1, 3, False)], {'a': 4}), [('a', 'high')])\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"},"fixed":{"sha256":"ce7871ca447a0375c01414401f4069f99495a3b156059158d057f3ca3c2d867d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(peers, installed):\n    result = []\n    for name, low, high, optional in peers:\n        if name not in installed:\n            if not optional: result.append((name, 'missing'))\n            continue\n        version = installed[name]\n        if version < low: result.append((name, 'low'))\n        elif version >= high: result.append((name, 'high'))\n    return result\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve([], {}), [])\ncheck('fixture 2', solve([('a', 1, 3, False)], {}), [('a', 'missing')])\ncheck('fixture 3', solve([('a', 1, 3, True)], {}), [])\ncheck('fixture 4', solve([('a', 1, 3, False)], {'a': 0}), [('a', 'low')])\ncheck('fixture 5', solve([('a', 1, 3, False)], {'a': 1}), [])\ncheck('fixture 6', solve([('a', 1, 3, False)], {'a': 2}), [])\ncheck('fixture 7', solve([('a', 1, 3, False)], {'a': 3}), [('a', 'high')])\ncheck('fixture 8', solve([('a', 1, 3, False)], {'a': 4}), [('a', 'high')])\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":"xt-peer-validation-missing-class","generated_at":"2026-09-29T14:38:30.205852+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"An offline model of peer dependency diagnostics, suitable for testing build and release tooling without external services.","repair":"Distinguish absent installations from incompatible installed versions.","root_cause":"The implementation substitutes (name, 'low') for (name, 'missing'), so missing peers are classified as version failures.","sha256":"443dad90fe7e280e3e535f59459d1569d2421b9c442cb69b91d6bb8a077d67c7","title":"Peer dependency diagnostics: Missing peers are classified as version failures · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":37.816,"exit_code":1,"observations":[{"actual":[],"check":"fixture 1","expected":[],"passed":true},{"actual":[["a","high"]],"check":"fixture 2","expected":[["a","missing"]],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[["a","low"]],"check":"fixture 4","expected":[["a","low"]],"passed":true},{"actual":[],"check":"fixture 5","expected":[],"passed":true},{"actual":[],"check":"fixture 6","expected":[],"passed":true},{"actual":[["a","high"]],"check":"fixture 7","expected":[["a","high"]],"passed":true},{"actual":[["a","high"]],"check":"fixture 8","expected":[["a","high"]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"missing\"]], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", \"low\"]], \"expected\": [[\"a\", \"low\"]], \"passed\": true}, {\"check\": \"fixture 5\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 6\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 7\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"high\"]], \"passed\": true}, {\"check\": \"fixture 8\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"high\"]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.158,"exit_code":1,"observations":[{"actual":[],"check":"fixture 1","expected":[],"passed":true},{"actual":[["a","low"]],"check":"fixture 2","expected":[["a","missing"]],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[["a","low"]],"check":"fixture 4","expected":[["a","low"]],"passed":true},{"actual":[],"check":"fixture 5","expected":[],"passed":true},{"actual":[],"check":"fixture 6","expected":[],"passed":true},{"actual":[["a","high"]],"check":"fixture 7","expected":[["a","high"]],"passed":true},{"actual":[["a","high"]],"check":"fixture 8","expected":[["a","high"]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [[\"a\", \"low\"]], \"expected\": [[\"a\", \"missing\"]], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", \"low\"]], \"expected\": [[\"a\", \"low\"]], \"passed\": true}, {\"check\": \"fixture 5\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 6\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 7\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"high\"]], \"passed\": true}, {\"check\": \"fixture 8\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"high\"]], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":37.51,"exit_code":0,"observations":[{"actual":[],"check":"fixture 1","expected":[],"passed":true},{"actual":[["a","missing"]],"check":"fixture 2","expected":[["a","missing"]],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[["a","low"]],"check":"fixture 4","expected":[["a","low"]],"passed":true},{"actual":[],"check":"fixture 5","expected":[],"passed":true},{"actual":[],"check":"fixture 6","expected":[],"passed":true},{"actual":[["a","high"]],"check":"fixture 7","expected":[["a","high"]],"passed":true},{"actual":[["a","high"]],"check":"fixture 8","expected":[["a","high"]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [[\"a\", \"missing\"]], \"expected\": [[\"a\", \"missing\"]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", \"low\"]], \"expected\": [[\"a\", \"low\"]], \"passed\": true}, {\"check\": \"fixture 5\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 6\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 7\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"high\"]], \"passed\": true}, {\"check\": \"fixture 8\", \"actual\": [[\"a\", \"high\"]], \"expected\": [[\"a\", \"high\"]], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}