Adds AlarmSubscribeIntegrationTests alongside HistoryReadIntegrationTests so both
optional driver capabilities — IHistoryProvider (already covered) and IAlarmSource
(new) — have end-to-end coverage that boots the full OPC UA stack and exercises the
wiring path from driver event → GenericDriverNodeManager forwarder → DriverNodeManager
ConditionSink through a real Session.
Two tests:
1. Driver_alarm_transition_updates_server_side_AlarmConditionState_node — a fake
IAlarmSource declares an IsAlarm=true variable, calls MarkAsAlarmCondition in
DiscoverAsync, and fires OnAlarmEvent for that source. Verifies the
client can browse the alarm condition node at FullReference + ".Condition"
and reads the DisplayName back through Session.Read.
2. Each_IsAlarm_variable_registers_its_own_condition_node_in_the_driver_namespace —
two IsAlarm variables each produce their own addressable AlarmConditionState,
proving the CapturingHandle per-variable registration works.
Scoped-out (documented in the class docstring): the stack exposes AlarmConditionState's
inherited children (Severity / Message / ActiveState / …) with Foundation-namespace
NodeIds that DriverNodeManager does not add to its predefined-node index, so reading
those child attributes through a client returns BadNodeIdUnknown. OPC UA Part 9 event
propagation (subscribe-on-Server + ConditionRefresh) is likewise out of reach until
the node manager wires HasNotifier + child-node registration. The existing Core-level
GenericDriverNodeManagerTests cover the in-memory alarm-sink fan-out semantics.
Full Server.Tests suite: 238 passed, 0 failed.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
