{"abstract":"A client serializes a typed range request plan: outbound members preserve caller priority order.","category":"HTTP ranges","checks":7,"contract":"Input x contains selectors [kind,a,b], validator [tag|date,value] or null, and accept encoding policy. Closed selectors serialize a-b, open selectors a-, suffix selectors -a, in input order. Empty selectors omit Range and If-Range. Tag validators are quoted opaque ASCII strings without quotes/backslashes; dates are already formatted and remain unquoted. Identity-only policy emits Accept-Encoding identity. Return ordered [header,value] pairs.","contract_signature":"x","evaluation_group":"s3-http_ranges-outbound-range-request","failed_approach":"The partial repair uses members=[]\nfor kind,a,b in reversed(x['selectors']):\n    if kind=='closed': members.append(str(a)+'-'+str(b))\n    elif kind=='open': members.append(str(a)+'-')\n    elif kind=='suffix': members.append('-'+str(a))\nheaders=[]\nif members:\n    headers.append(['Range','bytes='+','.join(members)])\n    if x['validator'] is not None:\n        kind,value=x['validator']\n        headers.append(['If-Range','\"'+value+'\"' if kind=='tag' else value])\nif x['identity']: headers.append(['Accept-Encoding','identity'])\nreturn headers, which still violates the stated contract.","family":"s3-http_ranges-outbound-range-request-member-order","id":"FA-27006","implementations":{"attempt":{"sha256":"857d4bab6b18d7355ac8e386da959b7f8fe458f1c939c07e3aff96e15582a866","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    members=[]\n    for kind,a,b in reversed(x['selectors']):\n        if kind=='closed': members.append(str(a)+'-'+str(b))\n        elif kind=='open': members.append(str(a)+'-')\n        elif kind=='suffix': members.append('-'+str(a))\n    headers=[]\n    if members:\n        headers.append(['Range','bytes='+','.join(members)])\n        if x['validator'] is not None:\n            kind,value=x['validator']\n            headers.append(['If-Range','\"'+value+'\"' if kind=='tag' else value])\n    if x['identity']: headers.append(['Accept-Encoding','identity'])\n    return headers\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('member-order fixture 0', json.loads(json.dumps(solve({'selectors':[['closed',0,N],['suffix',2,None]],'validator':['tag','rev'],'identity':True}))), json.loads(json.dumps([['Range',\"bytes=0-\"+str(N)+\",-2\"],['If-Range','\"rev\"'],['Accept-Encoding','identity']])))\ncheck('member-order fixture 1', json.loads(json.dumps(solve({'selectors':[['open',5,None]],'validator':['date','Mon, 01 Jan 2001 00:00:00 GMT'],'identity':False}))), json.loads(json.dumps([['Range','bytes=5-'],['If-Range','Mon, 01 Jan 2001 00:00:00 GMT']])))\ncheck('member-order fixture 2', json.loads(json.dumps(solve({'selectors':[],'validator':['tag','rev'],'identity':False}))), json.loads(json.dumps([])))\ncheck('member-order fixture 3', json.loads(json.dumps(solve({'selectors':[['closed',9,9],['closed',0,0]],'validator':None,'identity':False}))), json.loads(json.dumps([['Range','bytes=9-9,0-0']])))\ncheck('member-order fixture 4', json.loads(json.dumps(solve({'selectors':[['suffix',0,None]],'validator':['tag',''],'identity':False}))), json.loads(json.dumps([['Range','bytes=-0'],['If-Range','\"\"']])))\ncheck('member-order fixture 5', json.loads(json.dumps(solve({'selectors':[],'validator':None,'identity':True}))), json.loads(json.dumps([['Accept-Encoding','identity']])))\ncheck('member-order fixture 6', json.loads(json.dumps(solve({'selectors':[['open',0,None]],'validator':None,'identity':False}))), json.loads(json.dumps([['Range','bytes=0-']])))\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":"29fd959c745104764978397221d59fd3c558efca7c3c4f08a08d8c917c7bb3c1","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    members=[]\n    for kind,a,b in sorted(x['selectors'],key=lambda row:row[1]):\n        if kind=='closed': members.append(str(a)+'-'+str(b))\n        elif kind=='open': members.append(str(a)+'-')\n        elif kind=='suffix': members.append('-'+str(a))\n    headers=[]\n    if members:\n        headers.append(['Range','bytes='+','.join(members)])\n        if x['validator'] is not None:\n            kind,value=x['validator']\n            headers.append(['If-Range','\"'+value+'\"' if kind=='tag' else value])\n    if x['identity']: headers.append(['Accept-Encoding','identity'])\n    return headers\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('member-order fixture 0', json.loads(json.dumps(solve({'selectors':[['closed',0,N],['suffix',2,None]],'validator':['tag','rev'],'identity':True}))), json.loads(json.dumps([['Range',\"bytes=0-\"+str(N)+\",-2\"],['If-Range','\"rev\"'],['Accept-Encoding','identity']])))\ncheck('member-order fixture 1', json.loads(json.dumps(solve({'selectors':[['open',5,None]],'validator':['date','Mon, 01 Jan 2001 00:00:00 GMT'],'identity':False}))), json.loads(json.dumps([['Range','bytes=5-'],['If-Range','Mon, 01 Jan 2001 00:00:00 GMT']])))\ncheck('member-order fixture 2', json.loads(json.dumps(solve({'selectors':[],'validator':['tag','rev'],'identity':False}))), json.loads(json.dumps([])))\ncheck('member-order fixture 3', json.loads(json.dumps(solve({'selectors':[['closed',9,9],['closed',0,0]],'validator':None,'identity':False}))), json.loads(json.dumps([['Range','bytes=9-9,0-0']])))\ncheck('member-order fixture 4', json.loads(json.dumps(solve({'selectors':[['suffix',0,None]],'validator':['tag',''],'identity':False}))), json.loads(json.dumps([['Range','bytes=-0'],['If-Range','\"\"']])))\ncheck('member-order fixture 5', json.loads(json.dumps(solve({'selectors':[],'validator':None,'identity':True}))), json.loads(json.dumps([['Accept-Encoding','identity']])))\ncheck('member-order fixture 6', json.loads(json.dumps(solve({'selectors':[['open',0,None]],'validator':None,'identity':False}))), json.loads(json.dumps([['Range','bytes=0-']])))\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":"Deterministic simplified range service, with stipulated local policies and already parsed trusted inputs; not a complete HTTP 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"s3-http_ranges-outbound-range-request-member-order","generated_at":"2026-09-29T14:41:21.213324+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Range responses combine representation identity, conditional requests, framing, and partial-object state.","root_cause":"The outbound-range-request-member-order decision uses members=[]\nfor kind,a,b in sorted(x['selectors'],key=lambda row:row[1]):\n    if kind=='closed': members.append(str(a)+'-'+str(b))\n    elif kind=='open': members.append(str(a)+'-')\n    elif kind=='suffix': members.append('-'+str(a))\nheaders=[]\nif members:\n    headers.append(['Range','bytes='+','.join(members)])\n    if x['validator'] is not None:\n        kind,value=x['validator']\n        headers.append(['If-Range','\"'+value+'\"' if kind=='tag' else value])\nif x['identity']: headers.append(['Accept-Encoding','identity'])\nreturn headers.","sha256":"c76c3b4f74a493f5df84dc6a069024e9303e3e0f47ac793292f71226b6d59da1","title":"A client serializes a typed range request plan: outbound members preserve caller priority order · 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":78.313,"exit_code":1,"observations":[{"actual":[["Range","bytes=-2,0-1"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"check":"member-order fixture 0","expected":[["Range","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"passed":false},{"actual":[["Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"check":"member-order fixture 1","expected":[["Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"passed":true},{"actual":[],"check":"member-order fixture 2","expected":[],"passed":true},{"actual":[["Range","bytes=0-0,9-9"]],"check":"member-order fixture 3","expected":[["Range","bytes=9-9,0-0"]],"passed":false},{"actual":[["Range","bytes=-0"],["If-Range","\"\""]],"check":"member-order fixture 4","expected":[["Range","bytes=-0"],["If-Range","\"\""]],"passed":true},{"actual":[["Accept-Encoding","identity"]],"check":"member-order fixture 5","expected":[["Accept-Encoding","identity"]],"passed":true},{"actual":[["Range","bytes=0-"]],"check":"member-order fixture 6","expected":[["Range","bytes=0-"]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"member-order fixture 0\", \"actual\": [[\"Range\", \"bytes=-2,0-1\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Range\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"passed\": false}, {\"check\": \"member-order fixture 1\", \"actual\": [[\"Range\", \"bytes=5-\"], [\"If-Range\", \"Mon, 01 Jan 2001 00:00:00 GMT\"]], \"expected\": [[\"Range\", \"bytes=5-\"], [\"If-Range\", \"Mon, 01 Jan 2001 00:00:00 GMT\"]], \"passed\": true}, {\"check\": \"member-order fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"member-order fixture 3\", \"actual\": [[\"Range\", \"bytes=0-0,9-9\"]], \"expected\": [[\"Range\", \"bytes=9-9,0-0\"]], \"passed\": false}, {\"check\": \"member-order fixture 4\", \"actual\": [[\"Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"expected\": [[\"Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"passed\": true}, {\"check\": \"member-order fixture 5\", \"actual\": [[\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Accept-Encoding\", \"identity\"]], \"passed\": true}, {\"check\": \"member-order fixture 6\", \"actual\": [[\"Range\", \"bytes=0-\"]], \"expected\": [[\"Range\", \"bytes=0-\"]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":84.044,"exit_code":1,"observations":[{"actual":[["Range","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"check":"member-order fixture 0","expected":[["Range","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"passed":true},{"actual":[["Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"check":"member-order fixture 1","expected":[["Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"passed":true},{"actual":[],"check":"member-order fixture 2","expected":[],"passed":true},{"actual":[["Range","bytes=0-0,9-9"]],"check":"member-order fixture 3","expected":[["Range","bytes=9-9,0-0"]],"passed":false},{"actual":[["Range","bytes=-0"],["If-Range","\"\""]],"check":"member-order fixture 4","expected":[["Range","bytes=-0"],["If-Range","\"\""]],"passed":true},{"actual":[["Accept-Encoding","identity"]],"check":"member-order fixture 5","expected":[["Accept-Encoding","identity"]],"passed":true},{"actual":[["Range","bytes=0-"]],"check":"member-order fixture 6","expected":[["Range","bytes=0-"]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"member-order fixture 0\", \"actual\": [[\"Range\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Range\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"passed\": true}, {\"check\": \"member-order fixture 1\", \"actual\": [[\"Range\", \"bytes=5-\"], [\"If-Range\", \"Mon, 01 Jan 2001 00:00:00 GMT\"]], \"expected\": [[\"Range\", \"bytes=5-\"], [\"If-Range\", \"Mon, 01 Jan 2001 00:00:00 GMT\"]], \"passed\": true}, {\"check\": \"member-order fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"member-order fixture 3\", \"actual\": [[\"Range\", \"bytes=0-0,9-9\"]], \"expected\": [[\"Range\", \"bytes=9-9,0-0\"]], \"passed\": false}, {\"check\": \"member-order fixture 4\", \"actual\": [[\"Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"expected\": [[\"Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"passed\": true}, {\"check\": \"member-order fixture 5\", \"actual\": [[\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Accept-Encoding\", \"identity\"]], \"passed\": true}, {\"check\": \"member-order fixture 6\", \"actual\": [[\"Range\", \"bytes=0-\"]], \"expected\": [[\"Range\", \"bytes=0-\"]], \"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."}}