Better synchronization for mojo model update

On previous solution code flow could squeeze between conditions of queue and running update, but now we are done only after we done.

Fixup for b6c80a2

mojo/core/src/main/java/com/perl5/lang/mojolicious/model/MojoProjectManager.java

@@ -45,6 +45,7 @@
 import org.jetbrains.annotations.TestOnly;
 
 import java.util.*;
+import com.intellij.util.concurrency.Semaphore;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.BooleanSupplier;
 
@@ -56,6 +57,7 @@ public class MojoProjectManager implements Disposable {
   private final @NotNull MergingUpdateQueue myUpdateQueue;
   private final @NotNull AtomicBoolean myUpdatingModel = new AtomicBoolean(false);
   private volatile @NotNull Model myModel = new Model(Collections.emptySet());
+  private volatile Semaphore myTestSemaphore;
 
   public MojoProjectManager(@NotNull Project project) {
     myProject = project;
@@ -140,7 +142,16 @@ private void updateModel() {
             scheduleUpdate();
           }
           else {
-            doUpdateModel();
+            try{
+              LOG.debug("Performing model update");
+              doUpdateModel();
+            }
+            finally {
+              if( myTestSemaphore != null) {
+                myTestSemaphore.up();
+                myTestSemaphore = null;
+              }
+            }
           }
         });
       }
@@ -281,7 +292,9 @@ private Set<MojoProject> getProjects() {
 
   @TestOnly
   public BooleanSupplier updateInTestMode() {
+    var semaphore = new Semaphore(1);
+    myTestSemaphore = semaphore;
     updateModel();
-    return ()-> myUpdateQueue.isEmpty() && !myUpdatingModel.get();
+    return semaphore::isUp;
   }
 }