Fix BusToSignalAdapter evalJac bug

GridKit/Model/PhasorDynamics/BusToSignalAdapter/BusToSignalAdapterImpl.hpp

@@ -186,7 +186,7 @@ namespace GridKit
     template <typename scalar_type, typename index_type>
     int BusToSignalAdapter<scalar_type, index_type>::evaluateJacobian()
     {
-      return 0;
+      return this->constructCoo();
     }
 
   } // namespace PhasorDynamics

tests/UnitTests/PhasorDynamics/BusToSignalAdapterTests.hpp

@@ -90,6 +90,23 @@ namespace GridKit
 
         return success.report(__func__);
       }
+
+      TestOutcome jacobian()
+      {
+        TestStatus success = true;
+
+        auto bus     = BusT(1.0, 0.0);
+        auto adapter = AdapterT(&bus);
+        bus.allocate();
+        adapter.allocate();
+
+        success *= (adapter.evaluateJacobian() == 0);
+
+        const auto* jacobian  = adapter.getCooJacobian();
+        success              *= (jacobian != nullptr && jacobian->getNnz() == 0);
+
+        return success.report(__func__);
+      }
     };
 
   } // namespace Testing

tests/UnitTests/PhasorDynamics/runBusToSignalAdapterTests.cpp

@@ -10,6 +10,7 @@ int main()
 
   result += test.constructor();
   result += test.residual();
+  result += test.jacobian();
 
   return result.summary();
 }