test(breadcrumbs): assert strict null on non-exact route map lookups

memory-bank/change-log.md

@@ -754,6 +754,36 @@ Follow-ups:
 - Next smaller slice candidate: add focused helper test for strict null behavior on empty-string/whitespace/non-exact path keys.
 - Next larger slice candidate: evaluate extractability of `/myportal/representation` back-link states via explicit callback injection, only if questionnaire/submit side-effects remain parity-safe and readable.
 
+### CL-22541-X: breadcrumbs smaller slice — strict null lookup guard coverage (empty/whitespace/non-exact paths)
+
+date: 2026-04-09  
+author: Cline  
+scope: `tests/phase22/breadcrumb-route-maps-helper.test.cjs`  
+type: change  
+rationale: Execute the queued smaller follow-up slice by hardening helper regression coverage for strict exact-match route lookup semantics.
+impact: Test-only hardening; no runtime route/auth/session/API/EN-CY/a11y behavior change.
+status: completed
+
+Summary:
+
+- Added focused helper-level test case in `tests/phase22/breadcrumb-route-maps-helper.test.cjs`:
+    - `resolveMappedRouteRenderer returns null for empty, whitespace, and non-exact path variants`
+- New assertions verify resolver returns `null` for:
+    - empty path (`""`)
+    - whitespace-only path (`"   "`)
+    - trailing/leading whitespace variants (`"/known "`, `" /known"`)
+    - case-variant non-exact key (`"/KNOWN"`)
+- Confirms route-map resolver remains strict/exact and does not auto-trim or case-normalize lookup keys.
+
+Validation:
+
+- `npx eslint tests/phase22/breadcrumb-route-maps-helper.test.cjs tests/phase22/index.test.cjs` -> pass.
+- `node tests/phase22/index.test.cjs` -> pass (combined suite; breadcrumb-route-maps-helper 6/6).
+
+Follow-ups:
+
+- Next larger slice candidate remains `/myportal/representation` callback/state branch extraction only if side-effects can be injected/parity-preserved cleanly.
+
 ### CL-00X: 22500 `components/elements/index.js` Phase 1 helper extraction
 
 date: 2026-04-07