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Navigation active-link matching: Case-insensitive navigation still compares raw case · case 01

Case-insensitive navigation still compares raw case.

Verified by executionVariant 1 · 11 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The case operation uses `if False:` where the contract requires `if not case_sensitive:`.

VERIFIED REPAIR

Implement the case operation as `if not case_sensitive:`.

Unsuccessful approach: Always folding incorrectly activates case-sensitive links.

Case contract

Ignore URL query and fragment; normalize trailing slashes with root preserved; honor case policy; section matches require a slash boundary and root matches exactly.

Why this case matters

A deterministic model of navigation active-link matching; this isolates one interface invariant without requiring a browser.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(path, link, exact, case_sensitive):
    path = path.split('?', 1)[0].split('#', 1)[0]
    link = link.rstrip('/') or '/'
    path = path.rstrip('/') or '/'
    if False: path, link = path.casefold(), link.casefold()
    if exact or link == '/': return path == link
    return path == link or path.startswith(link + '/')
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('query', solve('/docs?x=1', '/docs', True, True), True)
check('fragment', solve('/docs#intro', '/docs', True, True), True)
check('slash', solve('/docs', '/docs/', True, True), True)
check('root', solve('/docs', '/', False, True), False)
check('root itself', solve('/', '/', True, True), True)
check('fold', solve("/DOCS", "/docs", True, False), True)
check('sensitive', solve("/DOCS", "/docs", True, True), False)
check('child', solve('/docs/a', '/docs', False, True), True)
check('prefix sibling', solve('/docstring', '/docs', False, True), False)
check('parameterized route segment', solve('/section'+str(N)+'/child','/section'+str(N),False,True), True)
for repetition in range(N):
    check('repeat prefix sibling', solve('/docstring', '/docs', False, True), 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
queryTrueTruePassed
fragmentTrueTruePassed
slashTrueTruePassed
rootFalseFalsePassed
root itselfTrueTruePassed
foldFalseTrueFailed
sensitiveFalseFalsePassed
childTrueTruePassed
prefix siblingFalseFalsePassed
parameterized route segmentTrueTruePassed
repeat prefix siblingFalseFalsePassed

SHA-256 / 2c714859774522b03814aece423232a713f5f9d2645be54641ca335fadb01a05

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(path, link, exact, case_sensitive):
    path = path.split('?', 1)[0].split('#', 1)[0]
    link = link.rstrip('/') or '/'
    path = path.rstrip('/') or '/'
    if True: path, link = path.casefold(), link.casefold()
    if exact or link == '/': return path == link
    return path == link or path.startswith(link + '/')
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('query', solve('/docs?x=1', '/docs', True, True), True)
check('fragment', solve('/docs#intro', '/docs', True, True), True)
check('slash', solve('/docs', '/docs/', True, True), True)
check('root', solve('/docs', '/', False, True), False)
check('root itself', solve('/', '/', True, True), True)
check('fold', solve("/DOCS", "/docs", True, False), True)
check('sensitive', solve("/DOCS", "/docs", True, True), False)
check('child', solve('/docs/a', '/docs', False, True), True)
check('prefix sibling', solve('/docstring', '/docs', False, True), False)
check('parameterized route segment', solve('/section'+str(N)+'/child','/section'+str(N),False,True), True)
for repetition in range(N):
    check('repeat prefix sibling', solve('/docstring', '/docs', False, True), 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
queryTrueTruePassed
fragmentTrueTruePassed
slashTrueTruePassed
rootFalseFalsePassed
root itselfTrueTruePassed
foldTrueTruePassed
sensitiveTrueFalseFailed
childTrueTruePassed
prefix siblingFalseFalsePassed
parameterized route segmentTrueTruePassed
repeat prefix siblingFalseFalsePassed

SHA-256 / 38d0d1045183ae4b36ff052d18b4c6021e54ef68deb88ba7a0a3c61b19ee44db

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(path, link, exact, case_sensitive):
    path = path.split('?', 1)[0].split('#', 1)[0]
    link = link.rstrip('/') or '/'
    path = path.rstrip('/') or '/'
    if not case_sensitive: path, link = path.casefold(), link.casefold()
    if exact or link == '/': return path == link
    return path == link or path.startswith(link + '/')
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('query', solve('/docs?x=1', '/docs', True, True), True)
check('fragment', solve('/docs#intro', '/docs', True, True), True)
check('slash', solve('/docs', '/docs/', True, True), True)
check('root', solve('/docs', '/', False, True), False)
check('root itself', solve('/', '/', True, True), True)
check('fold', solve("/DOCS", "/docs", True, False), True)
check('sensitive', solve("/DOCS", "/docs", True, True), False)
check('child', solve('/docs/a', '/docs', False, True), True)
check('prefix sibling', solve('/docstring', '/docs', False, True), False)
check('parameterized route segment', solve('/section'+str(N)+'/child','/section'+str(N),False,True), True)
for repetition in range(N):
    check('repeat prefix sibling', solve('/docstring', '/docs', False, True), 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
queryTrueTruePassed
fragmentTrueTruePassed
slashTrueTruePassed
rootFalseFalsePassed
root itselfTrueTruePassed
foldTrueTruePassed
sensitiveFalseFalsePassed
childTrueTruePassed
prefix siblingFalseFalsePassed
parameterized route segmentTrueTruePassed
repeat prefix siblingFalseFalsePassed

SHA-256 / 5f4fba5b804be1fd36d31301a615d617455f49d9f15a48c72b61e31b818c9a6b

Verification & scope

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 2026-09-29T14:38:23.314179+00:00.

Case digest / ff50d612799c7b172ac5303f43f1e8498a2b3c09ed97356a212aaf7de161c124