test(mps-sync-plugin): require sync in test to run without exceptions

While it's useful to continue synchronization in production, tests are there to find these
exceptions.

Author: slisson

mps-sync-plugin3/src/main/kotlin/org/modelix/mps/sync3/BindingWorker.kt

@@ -43,6 +43,7 @@ class BindingWorker(
     val serverConnection: ModelSyncService.Connection,
     val branchRef: BranchReference,
     val initialVersionHash: String?,
+    val continueOnError: () -> Boolean,
 ) {
     companion object {
         val LOG = KotlinLogging.logger { }
@@ -274,7 +275,10 @@ class BindingWorker(
                     nodeAssociation = NodeAssociationFromModelServer(branch, targetRoot.getModel()),
                     sourceMask = MPSProjectSyncMask(listOf(mpsProject), false),
                     targetMask = MPSProjectSyncMask(listOf(mpsProject), true),
-                    onException = { getMPSListener().synchronizationErrorHappened() },
+                    onException = {
+                        if (!continueOnError()) throw it
+                        getMPSListener().synchronizationErrorHappened()
+                    },
                 ).executeSync()
             }
         }
@@ -335,6 +339,7 @@ class BindingWorker(
                             nodeAssociation = nodeAssociation,
                             sourceMask = MPSProjectSyncMask(listOf(mpsProject), true),
                             targetMask = MPSProjectSyncMask(listOf(mpsProject), false),
+                            onException = { if (!continueOnError()) throw it },
                         ).executeSync()
                     }
                 }

mps-sync-plugin3/src/main/kotlin/org/modelix/mps/sync3/IModelSyncService.kt

@@ -11,6 +11,8 @@ import java.io.Closeable
 
 interface IModelSyncService {
     companion object {
+        var continueOnError: Boolean? = null
+
         @JvmStatic
         fun getInstance(project: com.intellij.openapi.project.Project): IModelSyncService {
             return project.service<ModelSyncService>()

mps-sync-plugin3/src/main/kotlin/org/modelix/mps/sync3/ModelSyncService.kt

@@ -168,6 +168,7 @@ class ModelSyncService(val project: Project) :
                 serverConnection = addServer(id.url),
                 branchRef = id.branchRef,
                 initialVersionHash = state?.versionHash,
+                continueOnError = { IModelSyncService.continueOnError ?: true },
             )
         }
     }

mps-sync-plugin3/src/test/kotlin/org/modelix/mps/sync3/MPSTestBase.kt

@@ -31,6 +31,7 @@ abstract class MPSTestBase : UsefulTestCase() {
     override fun setUp() {
         super.setUp()
         TestApplicationManager.getInstance()
+        IModelSyncService.continueOnError = false
     }
 
     @OptIn(ExperimentalPathApi::class)