{"abstract":"A client serializes a typed range request plan: Range requests do not send response-only Content-Range fields.","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 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(['Ranges','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-request-field-name","id":"FA-27016","implementations":{"attempt":{"sha256":"b4fba6c84b71da462f516e7ed29a6f3ef3a47c97397db1100e629ba632a965b7","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 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(['Ranges','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('request-field-name 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('request-field-name 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('request-field-name fixture 2', json.loads(json.dumps(solve({'selectors':[],'validator':['tag','rev'],'identity':False}))), json.loads(json.dumps([])))\ncheck('request-field-name 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('request-field-name 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('request-field-name fixture 5', json.loads(json.dumps(solve({'selectors':[],'validator':None,'identity':True}))), json.loads(json.dumps([['Accept-Encoding','identity']])))\ncheck('request-field-name 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":"82e55c174ca0ac02147ebb22b7bc7818aedbed3a592cd34a5c15bdfcdb37aabb","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 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(['Content-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('request-field-name 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('request-field-name 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('request-field-name fixture 2', json.loads(json.dumps(solve({'selectors':[],'validator':['tag','rev'],'identity':False}))), json.loads(json.dumps([])))\ncheck('request-field-name 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('request-field-name 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('request-field-name fixture 5', json.loads(json.dumps(solve({'selectors':[],'validator':None,'identity':True}))), json.loads(json.dumps([['Accept-Encoding','identity']])))\ncheck('request-field-name 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-request-field-name","generated_at":"2026-09-29T14:41:21.374890+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-request-field-name decision uses members=[]\nfor kind,a,b in 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(['Content-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":"ba27026c54a7406334d566b23f600fd286aa27e7cdb39a0f0ffdc9b8b2378e4c","title":"A client serializes a typed range request plan: Range requests do not send response-only Content-Range fields · 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":41.143,"exit_code":1,"observations":[{"actual":[["Ranges","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"check":"request-field-name fixture 0","expected":[["Range","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"passed":false},{"actual":[["Ranges","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"check":"request-field-name fixture 1","expected":[["Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"passed":false},{"actual":[],"check":"request-field-name fixture 2","expected":[],"passed":true},{"actual":[["Ranges","bytes=9-9,0-0"]],"check":"request-field-name fixture 3","expected":[["Range","bytes=9-9,0-0"]],"passed":false},{"actual":[["Ranges","bytes=-0"],["If-Range","\"\""]],"check":"request-field-name fixture 4","expected":[["Range","bytes=-0"],["If-Range","\"\""]],"passed":false},{"actual":[["Accept-Encoding","identity"]],"check":"request-field-name fixture 5","expected":[["Accept-Encoding","identity"]],"passed":true},{"actual":[["Ranges","bytes=0-"]],"check":"request-field-name fixture 6","expected":[["Range","bytes=0-"]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"request-field-name fixture 0\", \"actual\": [[\"Ranges\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Range\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"passed\": false}, {\"check\": \"request-field-name fixture 1\", \"actual\": [[\"Ranges\", \"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\": false}, {\"check\": \"request-field-name fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"request-field-name fixture 3\", \"actual\": [[\"Ranges\", \"bytes=9-9,0-0\"]], \"expected\": [[\"Range\", \"bytes=9-9,0-0\"]], \"passed\": false}, {\"check\": \"request-field-name fixture 4\", \"actual\": [[\"Ranges\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"expected\": [[\"Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"passed\": false}, {\"check\": \"request-field-name fixture 5\", \"actual\": [[\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Accept-Encoding\", \"identity\"]], \"passed\": true}, {\"check\": \"request-field-name fixture 6\", \"actual\": [[\"Ranges\", \"bytes=0-\"]], \"expected\": [[\"Range\", \"bytes=0-\"]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.52,"exit_code":1,"observations":[{"actual":[["Content-Range","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"check":"request-field-name fixture 0","expected":[["Range","bytes=0-1,-2"],["If-Range","\"rev\""],["Accept-Encoding","identity"]],"passed":false},{"actual":[["Content-Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"check":"request-field-name fixture 1","expected":[["Range","bytes=5-"],["If-Range","Mon, 01 Jan 2001 00:00:00 GMT"]],"passed":false},{"actual":[],"check":"request-field-name fixture 2","expected":[],"passed":true},{"actual":[["Content-Range","bytes=9-9,0-0"]],"check":"request-field-name fixture 3","expected":[["Range","bytes=9-9,0-0"]],"passed":false},{"actual":[["Content-Range","bytes=-0"],["If-Range","\"\""]],"check":"request-field-name fixture 4","expected":[["Range","bytes=-0"],["If-Range","\"\""]],"passed":false},{"actual":[["Accept-Encoding","identity"]],"check":"request-field-name fixture 5","expected":[["Accept-Encoding","identity"]],"passed":true},{"actual":[["Content-Range","bytes=0-"]],"check":"request-field-name fixture 6","expected":[["Range","bytes=0-"]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"request-field-name fixture 0\", \"actual\": [[\"Content-Range\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Range\", \"bytes=0-1,-2\"], [\"If-Range\", \"\\\"rev\\\"\"], [\"Accept-Encoding\", \"identity\"]], \"passed\": false}, {\"check\": \"request-field-name fixture 1\", \"actual\": [[\"Content-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\": false}, {\"check\": \"request-field-name fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"request-field-name fixture 3\", \"actual\": [[\"Content-Range\", \"bytes=9-9,0-0\"]], \"expected\": [[\"Range\", \"bytes=9-9,0-0\"]], \"passed\": false}, {\"check\": \"request-field-name fixture 4\", \"actual\": [[\"Content-Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"expected\": [[\"Range\", \"bytes=-0\"], [\"If-Range\", \"\\\"\\\"\"]], \"passed\": false}, {\"check\": \"request-field-name fixture 5\", \"actual\": [[\"Accept-Encoding\", \"identity\"]], \"expected\": [[\"Accept-Encoding\", \"identity\"]], \"passed\": true}, {\"check\": \"request-field-name fixture 6\", \"actual\": [[\"Content-Range\", \"bytes=0-\"]], \"expected\": [[\"Range\", \"bytes=0-\"]], \"passed\": false}], \"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."}}