17 new tests in tests/gateway/test_subagent_protection_30170.py pin
down both the detection helper and the demotion behaviour:
* TestAgentHasActiveSubagents — 11 cases covering the precision and
defensiveness of _agent_has_active_subagents:
- returns False for None, _AGENT_PENDING_SENTINEL, and stub
agents that lack the _active_children attribute;
- returns False for an empty list (the steady state of an idle
AIAgent);
- returns True for one or many children;
- works when _active_children_lock is None (test stubs);
- rejects truthy MagicMock auto-attributes — this is the
regression-guard for "every MagicMock-based gateway test
suddenly demotes to queue mode" (which is how this was
originally found);
- accepts list/tuple/set as the children container.
* TestBusyHandlerDemotesInterruptForSubagents — 6 cases driving
_handle_active_session_busy_message directly:
- parent.interrupt is NOT called when subagents are active,
message is still merged into the pending queue;
- ack copy mentions "Subagent working", "queued", and the
/stop escape hatch — and does NOT mention "Interrupting";
- with no subagents, behaviour is byte-identical to the
pre-#30170 interrupt path (parent.interrupt called with the
user text, ack says "Interrupting");
- configured queue mode keeps its vanilla "Queued for the next
turn" ack (the #30170 demotion-specific copy must NOT fire);
- configured steer mode still routes to running_agent.steer()
even when subagents are active (the guard is interrupt-only);
- _AGENT_PENDING_SENTINEL does not trigger demotion.
Refs #30170.
737ee81167