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FA-28921 / HTTP redirects / Open access

Match query-aware redirect rules against repeated decoded query fields: exact value not substring · case 01

Match query-aware redirect rules against repeated decoded query fields: the exact value not substring branch emits an incorrect decision.

Verified by executionVariant 1 · 9 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The exact-value-not-substring decision uses 'any(required in v for k,v in pairs if k==key)'; this violates the stipulated controller policy.

THE FAILURE

The exact-value-not-substring decision uses 'any(required in v for k,v in pairs if k==key)'; this violates the stipulated controller policy.

Unsuccessful approach: The partial repair uses 'any(v.startswith(required) for k,v in pairs if k==key)' and still fails an explicit boundary or control.

Case contract

Match query-aware redirect rules against repeated decoded query fields. The explicit fixture inputs and outputs define a bounded offline policy; request identity must accompany the decision.

Why this case matters

Models a redirect controller decision before following a target or exposing a redirect result.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from urllib.parse import urlsplit, unquote, quote
import posixpath
import re
N = 1
observations = []
def solve(request, pairs, key, required, case_sensitive, negate, require_all):
    return {'request': request, 'decision': [[v for k,v in pairs if k==key], [v for k,v in pairs if (k==key if case_sensitive else k.lower()==key.lower())], any(unquote(v)==required for k,v in pairs if k==key), any(k==key for k,v in pairs), bool([v for k,v in pairs if k==key]) and all(v==required for k,v in pairs if k==key), not any(v==required for k,v in pairs if k==key) if negate else any(v==required for k,v in pairs if k==key), any(required in v for k,v in pairs if k==key), sum(k==key for k,v in pairs), any(k==key and v==required for k,v in pairs), (bool(pairs) and all(v==required for k,v in pairs)) if require_all else any(v==required for k,v in pairs)]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', [['q', 'a'], ['q', 'b']], 'q', 'b', True, False, False), {'request': '/requests/' + str(N) + '/0', 'decision': [['a', 'b'], ['a', 'b'], True, True, False, True, True, 2, True, True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', [['Q', 'A']], 'q', 'a', False, False, True), {'request': '/requests/' + str(N) + '/1', 'decision': [[], ['A'], False, False, False, False, False, 0, False, False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], 'q', '', True, True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [[], [], False, False, False, True, False, 0, False, False]})
check('fixture 4', solve('/requests/' + str(N) + '/3', [['q', ''], ['q', 'x']], 'q', '', True, False, True), {'request': '/requests/' + str(N) + '/3', 'decision': [['', 'x'], ['', 'x'], True, True, False, True, True, 2, True, False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', [['q', 'a'], ['q', 'a']], 'q', 'a', True, True, True), {'request': '/requests/' + str(N) + '/4', 'decision': [['a', 'a'], ['a', 'a'], True, True, True, False, True, 2, True, True]})
check('fixture 6', solve('/requests/' + str(N) + '/5', [['q', 'a%20b']], 'q', 'a b', True, False, False), {'request': '/requests/' + str(N) + '/5', 'decision': [['a%20b'], ['a%20b'], True, True, False, False, False, 1, False, False]})
check('fixture 7', solve('/requests/' + str(N) + '/6', [['Q', 'a']], 'q', 'a', True, False, False), {'request': '/requests/' + str(N) + '/6', 'decision': [[], [], False, False, False, False, False, 0, False, True]})
check('fixture 8', solve('/requests/' + str(N) + '/7', [['q', '']], 'q', '', True, False, False), {'request': '/requests/' + str(N) + '/7', 'decision': [[''], [''], True, True, True, True, True, 1, True, True]})
check('fixture 9', solve('/requests/' + str(N) + '/8', [['q', 'prefix']], 'q', 'pre', True, False, False), {'request': '/requests/' + str(N) + '/8', 'decision': [['prefix'], ['prefix'], False, True, False, False, False, 1, False, False]})
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1{'decision': [['a', 'b'], ['a', 'b'], True, True, False, True, True, 2, True, True], 'request': '/requests/1/0'}{'decision': [['a', 'b'], ['a', 'b'], True, True, False, True, True, 2, True, True], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [[], ['A'], False, False, False, False, False, 0, False, False], 'request': '/requests/1/1'}{'decision': [[], ['A'], False, False, False, False, False, 0, False, False], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [[], [], False, False, False, True, False, 0, False, False], 'request': '/requests/1/2'}{'decision': [[], [], False, False, False, True, False, 0, False, False], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [['', 'x'], ['', 'x'], True, True, False, True, True, 2, True, False], 'request': '/requests/1/3'}{'decision': [['', 'x'], ['', 'x'], True, True, False, True, True, 2, True, False], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [['a', 'a'], ['a', 'a'], True, True, True, False, True, 2, True, True], 'request': '/requests/1/4'}{'decision': [['a', 'a'], ['a', 'a'], True, True, True, False, True, 2, True, True], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [['a%20b'], ['a%20b'], True, True, False, False, False, 1, False, False], 'request': '/requests/1/5'}{'decision': [['a%20b'], ['a%20b'], True, True, False, False, False, 1, False, False], 'request': '/requests/1/5'}Passed
fixture 7{'decision': [[], [], False, False, False, False, False, 0, False, True], 'request': '/requests/1/6'}{'decision': [[], [], False, False, False, False, False, 0, False, True], 'request': '/requests/1/6'}Passed
fixture 8{'decision': [[''], [''], True, True, True, True, True, 1, True, True], 'request': '/requests/1/7'}{'decision': [[''], [''], True, True, True, True, True, 1, True, True], 'request': '/requests/1/7'}Passed
fixture 9{'decision': [['prefix'], ['prefix'], False, True, False, False, True, 1, False, False], 'request': '/requests/1/8'}{'decision': [['prefix'], ['prefix'], False, True, False, False, False, 1, False, False], 'request': '/requests/1/8'}Failed

SHA-256 / dd48fc57c6e18279bc235c644964005ca108c5504ec04188b140bec4e8a3c9c0

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from urllib.parse import urlsplit, unquote, quote
import posixpath
import re
N = 1
observations = []
def solve(request, pairs, key, required, case_sensitive, negate, require_all):
    return {'request': request, 'decision': [[v for k,v in pairs if k==key], [v for k,v in pairs if (k==key if case_sensitive else k.lower()==key.lower())], any(unquote(v)==required for k,v in pairs if k==key), any(k==key for k,v in pairs), bool([v for k,v in pairs if k==key]) and all(v==required for k,v in pairs if k==key), not any(v==required for k,v in pairs if k==key) if negate else any(v==required for k,v in pairs if k==key), any(v.startswith(required) for k,v in pairs if k==key), sum(k==key for k,v in pairs), any(k==key and v==required for k,v in pairs), (bool(pairs) and all(v==required for k,v in pairs)) if require_all else any(v==required for k,v in pairs)]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', [['q', 'a'], ['q', 'b']], 'q', 'b', True, False, False), {'request': '/requests/' + str(N) + '/0', 'decision': [['a', 'b'], ['a', 'b'], True, True, False, True, True, 2, True, True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', [['Q', 'A']], 'q', 'a', False, False, True), {'request': '/requests/' + str(N) + '/1', 'decision': [[], ['A'], False, False, False, False, False, 0, False, False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], 'q', '', True, True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [[], [], False, False, False, True, False, 0, False, False]})
check('fixture 4', solve('/requests/' + str(N) + '/3', [['q', ''], ['q', 'x']], 'q', '', True, False, True), {'request': '/requests/' + str(N) + '/3', 'decision': [['', 'x'], ['', 'x'], True, True, False, True, True, 2, True, False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', [['q', 'a'], ['q', 'a']], 'q', 'a', True, True, True), {'request': '/requests/' + str(N) + '/4', 'decision': [['a', 'a'], ['a', 'a'], True, True, True, False, True, 2, True, True]})
check('fixture 6', solve('/requests/' + str(N) + '/5', [['q', 'a%20b']], 'q', 'a b', True, False, False), {'request': '/requests/' + str(N) + '/5', 'decision': [['a%20b'], ['a%20b'], True, True, False, False, False, 1, False, False]})
check('fixture 7', solve('/requests/' + str(N) + '/6', [['Q', 'a']], 'q', 'a', True, False, False), {'request': '/requests/' + str(N) + '/6', 'decision': [[], [], False, False, False, False, False, 0, False, True]})
check('fixture 8', solve('/requests/' + str(N) + '/7', [['q', '']], 'q', '', True, False, False), {'request': '/requests/' + str(N) + '/7', 'decision': [[''], [''], True, True, True, True, True, 1, True, True]})
check('fixture 9', solve('/requests/' + str(N) + '/8', [['q', 'prefix']], 'q', 'pre', True, False, False), {'request': '/requests/' + str(N) + '/8', 'decision': [['prefix'], ['prefix'], False, True, False, False, False, 1, False, False]})
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1{'decision': [['a', 'b'], ['a', 'b'], True, True, False, True, True, 2, True, True], 'request': '/requests/1/0'}{'decision': [['a', 'b'], ['a', 'b'], True, True, False, True, True, 2, True, True], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [[], ['A'], False, False, False, False, False, 0, False, False], 'request': '/requests/1/1'}{'decision': [[], ['A'], False, False, False, False, False, 0, False, False], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [[], [], False, False, False, True, False, 0, False, False], 'request': '/requests/1/2'}{'decision': [[], [], False, False, False, True, False, 0, False, False], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [['', 'x'], ['', 'x'], True, True, False, True, True, 2, True, False], 'request': '/requests/1/3'}{'decision': [['', 'x'], ['', 'x'], True, True, False, True, True, 2, True, False], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [['a', 'a'], ['a', 'a'], True, True, True, False, True, 2, True, True], 'request': '/requests/1/4'}{'decision': [['a', 'a'], ['a', 'a'], True, True, True, False, True, 2, True, True], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [['a%20b'], ['a%20b'], True, True, False, False, False, 1, False, False], 'request': '/requests/1/5'}{'decision': [['a%20b'], ['a%20b'], True, True, False, False, False, 1, False, False], 'request': '/requests/1/5'}Passed
fixture 7{'decision': [[], [], False, False, False, False, False, 0, False, True], 'request': '/requests/1/6'}{'decision': [[], [], False, False, False, False, False, 0, False, True], 'request': '/requests/1/6'}Passed
fixture 8{'decision': [[''], [''], True, True, True, True, True, 1, True, True], 'request': '/requests/1/7'}{'decision': [[''], [''], True, True, True, True, True, 1, True, True], 'request': '/requests/1/7'}Passed
fixture 9{'decision': [['prefix'], ['prefix'], False, True, False, False, True, 1, False, False], 'request': '/requests/1/8'}{'decision': [['prefix'], ['prefix'], False, True, False, False, False, 1, False, False], 'request': '/requests/1/8'}Failed

SHA-256 / e280906ad6be3f07c61361f370ae008a017a5d78ebaa16bf70edaedd1b407dc2

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 9 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

Stipulated offline redirect policy, not a complete HTTP, browser, URL, cache, or security implementation. Numbered variants vary request correlation identity. 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:41:38.379435+00:00.

Case digest / 1b72f127a3f2bd88fb8a089334a5d886140cc8a0d2c14cbac77f426f898b9cd2