Support multiple router calls and address issue #2175 (#2231)

Co-authored-by: Lorenze Jay <63378463+lorenzejay@users.noreply.github.com>

tests/flow_test.py

@@ -654,3 +654,104 @@ def test_flow_plotting():
     assert isinstance(received_events[0], FlowPlotEvent)
     assert received_events[0].flow_name == "StatelessFlow"
     assert isinstance(received_events[0].timestamp, datetime)
+
+
+def test_multiple_routers_from_same_trigger():
+    """Test that multiple routers triggered by the same method all activate their listeners."""
+    execution_order = []
+
+    class MultiRouterFlow(Flow):
+        def __init__(self):
+            super().__init__()
+            # Set diagnosed conditions to trigger all routers
+            self.state["diagnosed_conditions"] = "DHA"  # Contains D, H, and A
+
+        @start()
+        def scan_medical(self):
+            execution_order.append("scan_medical")
+            return "scan_complete"
+
+        @router(scan_medical)
+        def diagnose_conditions(self):
+            execution_order.append("diagnose_conditions")
+            return "diagnosis_complete"
+
+        @router(diagnose_conditions)
+        def diabetes_router(self):
+            execution_order.append("diabetes_router")
+            if "D" in self.state["diagnosed_conditions"]:
+                return "diabetes"
+            return None
+
+        @listen("diabetes")
+        def diabetes_analysis(self):
+            execution_order.append("diabetes_analysis")
+            return "diabetes_analysis_complete"
+
+        @router(diagnose_conditions)
+        def hypertension_router(self):
+            execution_order.append("hypertension_router")
+            if "H" in self.state["diagnosed_conditions"]:
+                return "hypertension"
+            return None
+
+        @listen("hypertension")
+        def hypertension_analysis(self):
+            execution_order.append("hypertension_analysis")
+            return "hypertension_analysis_complete"
+
+        @router(diagnose_conditions)
+        def anemia_router(self):
+            execution_order.append("anemia_router")
+            if "A" in self.state["diagnosed_conditions"]:
+                return "anemia"
+            return None
+
+        @listen("anemia")
+        def anemia_analysis(self):
+            execution_order.append("anemia_analysis")
+            return "anemia_analysis_complete"
+
+    flow = MultiRouterFlow()
+    flow.kickoff()
+
+    # Verify all methods were called
+    assert "scan_medical" in execution_order
+    assert "diagnose_conditions" in execution_order
+
+    # Verify all routers were called
+    assert "diabetes_router" in execution_order
+    assert "hypertension_router" in execution_order
+    assert "anemia_router" in execution_order
+
+    # Verify all listeners were called - this is the key test for the fix
+    assert "diabetes_analysis" in execution_order
+    assert "hypertension_analysis" in execution_order
+    assert "anemia_analysis" in execution_order
+
+    # Verify execution order constraints
+    assert execution_order.index("diagnose_conditions") > execution_order.index(
+        "scan_medical"
+    )
+
+    # All routers should execute after diagnose_conditions
+    assert execution_order.index("diabetes_router") > execution_order.index(
+        "diagnose_conditions"
+    )
+    assert execution_order.index("hypertension_router") > execution_order.index(
+        "diagnose_conditions"
+    )
+    assert execution_order.index("anemia_router") > execution_order.index(
+        "diagnose_conditions"
+    )
+
+    # All analyses should execute after their respective routers
+    assert execution_order.index("diabetes_analysis") > execution_order.index(
+        "diabetes_router"
+    )
+    assert execution_order.index("hypertension_analysis") > execution_order.index(
+        "hypertension_router"
+    )
+    assert execution_order.index("anemia_analysis") > execution_order.index(
+        "anemia_router"
+    )