feat(dag_engine): implement cascade_blocks and call in ExecutionEngine.tick

tests/test_arch_boundary_phase3.py

@@ -0,0 +1,60 @@
+import pytest
+from models import Ticket
+from dag_engine import TrackDAG, ExecutionEngine
+
+def test_cascade_blocks_simple() -> None:
+ """Test that a blocked dependency blocks its immediate dependent."""
+ t1 = Ticket(id="T1", description="T1", status="blocked", assigned_to="worker")
+ t2 = Ticket(id="T2", description="T2", status="todo", assigned_to="worker", depends_on=["T1"])
+ dag = TrackDAG([t1, t2])
+ dag.cascade_blocks()
+ assert t2.status == "blocked"
+
+def test_cascade_blocks_multi_hop() -> None:
+ """Test that blocking cascades through multiple levels: A(blocked) -> B -> C."""
+ t1 = Ticket(id="T1", description="T1", status="blocked", assigned_to="worker")
+ t2 = Ticket(id="T2", description="T2", status="todo", assigned_to="worker", depends_on=["T1"])
+ t3 = Ticket(id="T3", description="T3", status="todo", assigned_to="worker", depends_on=["T2"])
+ dag = TrackDAG([t1, t2, t3])
+ dag.cascade_blocks()
+ assert t2.status == "blocked"
+ assert t3.status == "blocked"
+
+def test_cascade_blocks_no_cascade_to_completed() -> None:
+ """Test that completed tasks are not changed even if a dependency is blocked (though this shouldn't normally happen)."""
+ t1 = Ticket(id="T1", description="T1", status="blocked", assigned_to="worker")
+ t2 = Ticket(id="T2", description="T2", status="completed", assigned_to="worker", depends_on=["T1"])
+ dag = TrackDAG([t1, t2])
+ dag.cascade_blocks()
+ assert t2.status == "completed"
+
+def test_cascade_blocks_partial_dependencies() -> None:
+ """Test that if one dependency is blocked, the dependent is blocked even if others are completed."""
+ t1 = Ticket(id="T1", description="T1", status="blocked", assigned_to="worker")
+ t2 = Ticket(id="T2", description="T2", status="completed", assigned_to="worker")
+ t3 = Ticket(id="T3", description="T3", status="todo", assigned_to="worker", depends_on=["T1", "T2"])
+ dag = TrackDAG([t1, t2, t3])
+ dag.cascade_blocks()
+ assert t3.status == "blocked"
+
+def test_cascade_blocks_already_in_progress() -> None:
+ """Test that in_progress tasks are not blocked automatically (only todo)."""
+ t1 = Ticket(id="T1", description="T1", status="blocked", assigned_to="worker")
+ t2 = Ticket(id="T2", description="T2", status="in_progress", assigned_to="worker", depends_on=["T1"])
+ dag = TrackDAG([t1, t2])
+ dag.cascade_blocks()
+ assert t2.status == "in_progress"
+
+def test_execution_engine_tick_cascades_blocks() -> None:
+ """Test that ExecutionEngine.tick() triggers the cascading blocks."""
+ t1 = Ticket(id="T1", description="T1", status="blocked", assigned_to="worker")
+ t2 = Ticket(id="T2", description="T2", status="todo", assigned_to="worker", depends_on=["T1"])
+ dag = TrackDAG([t1, t2])
+ engine = ExecutionEngine(dag)
+ 
+ # Before tick, T2 is todo
+ assert t2.status == "todo"
+ 
+ # After tick, T2 should be blocked
+ engine.tick()
+ assert t2.status == "blocked"