Deep Route Guard — Single Authority for Nested Invocation Charts

Field	Value
Status	Done
Priority	P1
Created	2026-02-18
Completed	2026-02-18
Owner	AI

Context

When child charts (via istate) use routing-regions, each level gets an independent route-guard and routing-info-state parallel region. This creates multiple independent guard systems that:

• Cannot see leaf components in invoked child charts
• Block routing independently instead of through a single authority
• Create duplicate routing-info modals at each nesting level

The routing-demo2 admin chart (admin_chart.cljc) demonstrates this: it wraps its routes in routing-regions just like the parent chart, producing two parallel routing-info regions.

Requirements

1. Only the top-level chart uses routing-regions. Child charts use bare routes with no guard.
2. The top-level route-guard walks the invocation tree through Fulcro state to check busy/guard conditions on route components at any depth.
3. routes accepts a :routing/guarded? option (default true). When false, the guard transition and routing-info raise are omitted.
4. No protocol changes. No new event patterns. Existing rstate/istate/routes APIs unchanged.

Approach

Actual Implementation

The implementation uses busy? (not route-guard) as the sole guard predicate — route-guard was removed entirely per the remove-route-guard spec.

Key functions:

• check-component-busy? — checks a single component, returns boolean (not keyword denial reason)
• deep-busy? — recursive walk through invocation tree with cycle protection (seen set). Uses each session's own local-data as the data context when checking components at that level.
• busy? — top-level guard on routes, delegates to deep-busy?
• routes accepts :routing/guarded? option (default true). When false, the guard transition is omitted — used by child charts invoked via istate.

Key Files

File	Role
src/main/com/fulcrologic/statecharts/integration/fulcro/ui_routing2.cljc	Main changes: extract guard, deep recursion, guarded? option
src/routing-demo2/com/fulcrologic/statecharts/routing_demo2/admin_chart.cljc	Demo update: drop routing-regions
src/main/com/fulcrologic/statecharts/integration/fulcro.cljc	Reuse: local-data-path, current-configuration
src/main/com/fulcrologic/statecharts/integration/fulcro_impl.cljc	Reuse: local-data-path impl
src/main/com/fulcrologic/statecharts/protocols.cljc	Reuse: get-statechart on registry

Verification

1. Existing ui-routes-test and all statechart tests pass
2. routing-demo2 navigates between all routes including admin sub-routes
3. Adding ro/route-guard to an admin child component triggers the top-level routing-info modal
4. Force-continue from top modal navigates through to the child route
5. Only one routing-info region active (in top chart)