fix rezani pv a

backend/tests/test_control_exporter_reg340.py

@@ -98,6 +98,22 @@ class BuildSetpointsReg340Tests(unittest.TestCase):
         assert sp is not None
         self.assertIsNone(sp.pv_a_allowed_w)
 
+    def test_neg_buy_and_sell_with_pv_b_forces_pv_a_off(self) -> None:
+        sp = _build_setpoints(
+            _auto_mode(),
+            _pi_base(
+                effective_buy_price=-3.0,
+                effective_sell_price=-2.0,
+                pv_b_forecast_solver_w=5000,
+                pv_a_forecast_solver_w=0,
+                pv_a_curtailed_w=0,
+            ),
+            pv_a_cap_w=3333,
+            inverter_manufacturer="Deye",
+        )
+        assert sp is not None
+        self.assertEqual(sp.pv_a_allowed_w, 0)
+
 
 class Reg340VerifyPolicyTests(unittest.TestCase):
     def test_reg340_not_critical_for_self_sustain(self) -> None: