Bug 329184 Detached view that is an activation target candidate can prevent perspective switching
1. Detach the 'Outline' view. 2. Window > Open Perspective > Debug 3. Window > Open Perspective > Java 4. The perspective switch doesn't actually happen. You see the 'Debug' perspective's content with an 'Outline' view detached. Closing the 'Outline' view in the 'Debug' perspective will workaround this problem.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
testShowPart_Part_MultipleNonexistent(true, PartState.CREATE);
	}
	public void testShowPart_Part_MultipleNonexistent_FalseCREATE() {
		testShowPart_Part_MultipleNonexistent(false, PartState.CREATE);
	}
	public void testShowPart_Part_MultipleWithoutCategory() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPartDescriptor partDescriptor = org.eclipse.e4.ui.model.application.descriptor.basic.impl.BasicFactoryImpl.eINSTANCE
				.createPartDescriptor();
		partDescriptor.setAllowMultiple(true);
		partDescriptor.setElementId("partId");
		application.getDescriptors().add(partDescriptor);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		MPart createdPart = partService.createPart("partId");
		MPart shownPart = partService.showPart(createdPart, PartState.ACTIVATE);
		assertNotNull(shownPart);
		assertEquals(createdPart, shownPart);
		MPart createdPart2 = partService.createPart("partId");
		MPart shownPart2 = partService.showPart(createdPart2,
				PartState.ACTIVATE);
		assertFalse(shownPart.equals(shownPart2));
	}
	public void testShowPart_Part_MultipleWithCategory() {