{"abstract":"Touching spans are incorrectly reported as overlapping.","category":"Annotation span alignment","checks":7,"contract":"Return true iff half-open intervals [a,b) and [c,d) share at least one position.","contract_signature":"a, b, c, d","evaluation_group":"annotation-span-touching-overlap-test","failed_approach":"Testing only strict start containment misses identical intervals with equal starts.","family":"w3-annotation-span-alignment-touching-overlap-test","id":"FA-100186","implementations":{"attempt":{"sha256":"7908537c8653d708ff7aeac16aa2d447ccee0fd40b31d6afc1a464f280ef6a97","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(a, b, c, d):\n    return a<c< b or c<a<d\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('touch at right edge', solve(0,N,N,N+2), False)\ncheck('touch at left edge', solve(N,N+2,0,N), False)\ncheck('positive overlap', solve(0,N+1,N,N+3), True)\ncheck('disjoint', solve(0,2,4,6), False)\ncheck('contained', solve(0,8,2,3), True)\ncheck('identical', solve(N,N+1,N,N+1), True)\ncheck('empty first', solve(2,2,1,3), False)\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":"8fead298434849ae57f71be57812124001a5f79e3d973e35c4e90abf74cee11d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(a, b, c, d):\n    return a<=d and c<=b\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('touch at right edge', solve(0,N,N,N+2), False)\ncheck('touch at left edge', solve(N,N+2,0,N), False)\ncheck('positive overlap', solve(0,N+1,N,N+3), True)\ncheck('disjoint', solve(0,2,4,6), False)\ncheck('contained', solve(0,8,2,3), True)\ncheck('identical', solve(N,N+1,N,N+1), True)\ncheck('empty first', solve(2,2,1,3), False)\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":"Contracts use integer offsets, explicit edits, and supplied token boundaries; they do not define a tokenizer or production annotation format. 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":"w3-annotation-span-alignment-touching-overlap-test","generated_at":"2026-09-30T16:48:32.646646+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A small offline annotation transformation keeps span coordinates explicit when text or token boundaries change.","root_cause":"The interval test uses inclusive endpoints for half-open spans.","sha256":"311f066bf555621876d9824405c7a192cfbb98ff97df3eacfa922e9b79a75c2e","title":"Touching spans are incorrectly reported as overlapping · case 01","variant":1,"variant_policy":"The fixture code references N, supplied as 1 through 5. Fixed boundary checks may repeat. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":28.352,"exit_code":1,"observations":[{"actual":false,"check":"touch at right edge","expected":false,"passed":true},{"actual":false,"check":"touch at left edge","expected":false,"passed":true},{"actual":true,"check":"positive overlap","expected":true,"passed":true},{"actual":false,"check":"disjoint","expected":false,"passed":true},{"actual":true,"check":"contained","expected":true,"passed":true},{"actual":false,"check":"identical","expected":true,"passed":false},{"actual":true,"check":"empty first","expected":false,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"touch at right edge\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"touch at left edge\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"positive overlap\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"disjoint\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"contained\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"identical\", \"actual\": false, \"expected\": true, \"passed\": false}, {\"check\": \"empty first\", \"actual\": true, \"expected\": false, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":27.417,"exit_code":1,"observations":[{"actual":true,"check":"touch at right edge","expected":false,"passed":false},{"actual":true,"check":"touch at left edge","expected":false,"passed":false},{"actual":true,"check":"positive overlap","expected":true,"passed":true},{"actual":false,"check":"disjoint","expected":false,"passed":true},{"actual":true,"check":"contained","expected":true,"passed":true},{"actual":true,"check":"identical","expected":true,"passed":true},{"actual":true,"check":"empty first","expected":false,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"touch at right edge\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"touch at left edge\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"positive overlap\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"disjoint\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"contained\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"identical\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"empty first\", \"actual\": true, \"expected\": false, \"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."}}