Add missing check on voltage level existence, when applying the bus modifications in a voltage init modification (#142)

Signed-off-by: Franck LECUYER <[email protected]>

Author: FranckLecuyer

src/main/java/org/gridsuite/modification/modifications/VoltageInitModification.java

@@ -81,10 +81,12 @@ private void applyBusModification(Network network, ReportNode subReportNode) {
         List<ReportNode> reports = new ArrayList<>();
         for (VoltageInitBusModificationInfos m : voltageInitModificationInfos.getBuses()) {
             String voltageLevelId = m.getVoltageLevelId();
-            Bus bus;
+            Bus bus = null;
             if (voltageLevelId != null) {
                 final VoltageLevel voltageLevel = network.getVoltageLevel(voltageLevelId);
-                bus = voltageLevel.getBusView().getBus(m.getBusId());
+                if (voltageLevel != null) {
+                    bus = voltageLevel.getBusView().getBus(m.getBusId());
+                }
             } else {
                 bus = network.getBusView().getBus(m.getBusId());
             }

src/test/java/org/gridsuite/modification/modifications/VoltageInitModificationTest.java

@@ -201,6 +201,12 @@ protected ModificationInfos buildModification() {
                     .busId("v1_0")
                     .v(230.)
                     .angle(0.5)
+                    .build(),
+                VoltageInitBusModificationInfos.builder()
+                    .voltageLevelId("vlNotFound")
+                    .busId("v1_0")
+                    .v(230.)
+                    .angle(0.5)
                     .build()))
             .rootNetworkName("rootNetwork1")
             .nodeName("node1")