fix(dispatch): prefilter sequence-held dev tasks before spawn (#519)

* fix(dispatch): prefilter sequence-held dev tasks before spawn _spawn_pending_dev booted a full dev container for a pre-assigned pending task that the assignee-blind sequence guard would refuse at the claim chokepoint (a non-terminal lower-sequence same-parent sibling — not a declared dependency). _blocked_by_earlier_lane_sibling is narrower (same dev's lane) and _validate_task_for_spawn checks declared deps, not sequence siblings, so the container spawned, the first claim hit _claim_blocked_by_sequence and was refused, and the agent exited only to be re-spawned next tick — pure churn until the predecessor went terminal. Mirror the PM path's _pending_claim_blocked prefilter (the exact claim-gate predicate, fails open) at the top of _spawn_pending_dev, before the narrower per-dev lane probe. Reuses the helper so it can't drift from the chokepoint. * fix(dispatch): prefilter sequence-held dev tasks before spawn _spawn_pending_dev booted a full dev container for a pre-assigned pending task that the assignee-blind sequence guard would refuse at the claim chokepoint (a non-terminal lower-sequence same-parent sibling — not a declared dependency). _blocked_by_earlier_lane_sibling is narrower (same dev's lane) and _validate_task_for_spawn checks declared deps, not sequence siblings, so the container spawned, the first claim hit _claim_blocked_by_sequence and was refused, and the agent exited only to be re-spawned next tick — pure churn until the predecessor went terminal. Mirror the PM path's _pending_claim_blocked prefilter (the exact claim-gate predicate, fails open) at the top of _spawn_pending_dev, before the narrower per-dev lane probe. Reuses the helper so it can't drift from the chokepoint. --------- Co-authored-by: Renn F <rennf93@users.noreply.github.com>
2026-08-03 07:23:24 +02:00 · 2026-07-15 04:33:06 +02:00
parent a9dee3b34e
commit ba9c9d69d8
2 changed files with 102 additions and 0 deletions
@@ -0,0 +1,95 @@
+"""Dev dispatch sequence pacing — no doomed spawn for a sequence-held task.
+
+``_spawn_pending_dev`` boots a full dev container for a pre-assigned pending
+task. Before this guard, a task held only by the assignee-blind sequence
+guard (a non-terminal lower-sequence same-parent sibling, not a declared
+dependency) passed every pre-spawn gate — ``_blocked_by_earlier_lane_sibling``
+is narrower (same dev's lane) and ``_validate_task_for_spawn`` checks declared
+dependencies, not sequence siblings — so the container spawned, the agent's
+first claim hit ``_claim_blocked_by_sequence`` at the chokepoint and was
+refused, and the agent exited only to be re-spawned next tick. Mirror the PM
+path's ``_pending_claim_blocked`` prefilter so a sequence-held task is skipped
+pre-spawn instead of churned.
+"""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Any, cast
+from unittest.mock import AsyncMock, patch
+from uuid import uuid4
+
+import pytest
+from roboco.runtime.orchestrator import AgentOrchestrator
+
+if TYPE_CHECKING:
+    import httpx
+
+
+def _orch() -> AgentOrchestrator:
+    orch = object.__new__(AgentOrchestrator)
+    orch._instances = {}
+    return orch
+
+
+def _pending_dev_task(**over: Any) -> dict[str, Any]:
+    base: dict[str, Any] = {
+        "id": str(uuid4()),
+        "status": "pending",
+        "team": "backend",
+        "task_type": "code",
+        "title": "Sequenced code leaf",
+        "assigned_to": str(uuid4()),
+    }
+    base.update(over)
+    return base
+
+
+@pytest.mark.asyncio
+async def test_sequence_held_dev_task_not_spawned() -> None:
+    """A sequence-held task skips spawn entirely — no container, no churn."""
+    orch = _orch()
+    task = _pending_dev_task()
+    client = cast("httpx.AsyncClient", object())
+    with (
+        patch.object(orch, "_is_agent_active", return_value=False),
+        patch.object(orch, "_pending_claim_blocked", new=AsyncMock(return_value=True)),
+        patch.object(orch, "_blocked_by_earlier_lane_sibling", new=AsyncMock()) as lane,
+        patch.object(orch, "_pm_respawn_should_gate", new=AsyncMock()) as respawn,
+        patch.object(orch, "spawn_agent", new=AsyncMock()) as spawn,
+    ):
+        await orch._spawn_pending_dev(client, task, "be-dev-1")
+
+    spawn.assert_not_awaited()
+    # Sequence guard is broader and checked first — narrower per-dev probe never runs.
+    lane.assert_not_awaited()
+    respawn.assert_not_awaited()
+
+
+@pytest.mark.asyncio
+async def test_ready_dev_task_still_spawns() -> None:
+    """A clear task (prefilter False, lane clear, respawn gate clear, valid)
+    proceeds to spawn unchanged."""
+    orch = _orch()
+    task = _pending_dev_task()
+    client = cast("httpx.AsyncClient", object())
+    with (
+        patch.object(orch, "_is_agent_active", return_value=False),
+        patch.object(orch, "_pending_claim_blocked", new=AsyncMock(return_value=False)),
+        patch.object(
+            orch, "_blocked_by_earlier_lane_sibling", new=AsyncMock(return_value=False)
+        ),
+        patch.object(
+            orch, "_pm_respawn_should_gate", new=AsyncMock(return_value=False)
+        ),
+        patch.object(
+            orch, "_validate_task_for_spawn", new=AsyncMock(return_value=None)
+        ),
+        patch.object(
+            orch, "_get_prompt_for_agent", new=AsyncMock(return_value="prompt")
+        ),
+        patch.object(orch, "_task_git_context", return_value=None),
+        patch.object(orch, "spawn_agent", new=AsyncMock()) as spawn,
+    ):
+        await orch._spawn_pending_dev(client, task, "be-dev-1")
+
+    spawn.assert_awaited_once()