Check device when running dispose execs

When Display#dispose is called during disposal (which is illegal), we
run into an exception in the Synchronizer.
We should rather fail fast and throw an SWT exception here.

See bug 389384: Calling Display#dispose() during disposal of the display
should throw SWT exception
https://bugs.eclipse.org/bugs/show_bug.cgi?id=389384

2 files changed, 20 insertions, 0 deletions

diff --git a/bundles/org.eclipse.rap.rwt/src/org/eclipse/swt/widgets/Display.java b/bundles/org.eclipse.rap.rwt/src/org/eclipse/swt/widgets/Display.java
index ad6cbbb4dd..26aa76130a 100644
--- a/bundles/org.eclipse.rap.rwt/src/org/eclipse/swt/widgets/Display.java
+++ b/bundles/org.eclipse.rap.rwt/src/org/eclipse/swt/widgets/Display.java
@@ -730,6 +730,7 @@ public class Display extends Device implements Adaptable {
   }
 
   private void runDisposeExecs() {
+    checkDevice();
     if( disposeList != null ) {
       for( int i = 0; i < disposeList.length; i++ ) {
         if( disposeList[ i ] != null ) {
diff --git a/tests/org.eclipse.rap.rwt.test/src/org/eclipse/swt/widgets/Display_Test.java b/tests/org.eclipse.rap.rwt.test/src/org/eclipse/swt/widgets/Display_Test.java
index 7f5e18b46b..7b3dc7855c 100644
--- a/tests/org.eclipse.rap.rwt.test/src/org/eclipse/swt/widgets/Display_Test.java
+++ b/tests/org.eclipse.rap.rwt.test/src/org/eclipse/swt/widgets/Display_Test.java
@@ -1405,6 +1405,25 @@ public class Display_Test extends TestCase {
     assertNull( display.getActiveShell() );
   }
 
+  public void testDisposeFailsWhenInDisposal() {
+    // See bug 389384
+    Fixture.fakePhase( PhaseId.PROCESS_ACTION );
+    final Display display = new Display();
+    Shell shell = new Shell( display );
+    shell.addDisposeListener( new DisposeListener() {
+      public void widgetDisposed( DisposeEvent event ) {
+        display.dispose();
+      }
+    } );
+
+    try {
+      display.dispose();
+      fail();
+    } catch( SWTException exception ) {
+      assertEquals( "Device is disposed", exception.getMessage() );
+    }
+  }
+
   private static void setCursorLocation( Display display, int x, int y ) {
     IDisplayAdapter adapter = display.getAdapter( IDisplayAdapter.class );
     adapter.setCursorLocation( x, y );