Bug 299272 Renderer cannot handle an MPart with a null label
java.lang.IllegalArgumentException: Argument cannot be null at org.eclipse.swt.SWT.error(SWT.java:4049) at org.eclipse.swt.SWT.error(SWT.java:3983) at org.eclipse.swt.SWT.error(SWT.java:3954) at org.eclipse.e4.ui.widgets.CTabItem.setText(CTabItem.java:1013) at org.eclipse.e4.workbench.ui.renderers.swt.StackRenderer.showChild(StackRenderer.java:296) at org.eclipse.e4.workbench.ui.renderers.swt.LazyStackRenderer.processContents(LazyStackRenderer.java:92) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine.createGui(PartRenderingEngine.java:300) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine.createGui(PartRenderingEngine.java:349) at org.eclipse.e4.workbench.ui.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:54) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine.createGui(PartRenderingEngine.java:300) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine.createGui(PartRenderingEngine.java:349) at org.eclipse.e4.workbench.ui.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:54) at org.eclipse.e4.workbench.ui.renderers.swt.WBWRenderer.processContents(WBWRenderer.java:369) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine.createGui(PartRenderingEngine.java:300) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine.createGui(PartRenderingEngine.java:349) at org.eclipse.e4.ui.workbench.swt.internal.PartRenderingEngine$4.run(PartRenderingEngine.java:510)
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/MPartTest.java
assertEquals(null, item.getToolTipText());
		MPartSashContainer container = (MPartSashContainer) window
				.getChildren().get(0);
		MPartStack stack = (MPartStack) container.getChildren().get(0);
		MPart part = stack.getChildren().get(0);
		part.setTooltip(partToolTip);
		assertEquals(expectedToolTip, item.getToolTipText());
	}
	public void testMPart_setTooltipNull() {
		testMPart_setTooltip(null, null);
	}
	public void testMPart_setTooltipEmptyString() {
		testMPart_setTooltip("", "");
	}
	public void testMPart_setTooltipDefined() {
		testMPart_setTooltip("partToolTip", "partToolTip");
	}
	public void testMPart_getContext() {
		final MWindow window = createWindowWithOneView("Part Name");
		MApplication application = MApplicationFactory.eINSTANCE
				.createApplication();
		application.getChildren().add(window);
		application.setContext(appContext);
		appContext.set(MApplication.class.getName(), application);
		wb = new E4Workbench(application, appContext);
		wb.createAndRunUI(window);
		MPartSashContainer container = (MPartSashContainer) window
				.getChildren().get(0);
		MPartStack stack = (MPartStack) container.getChildren().get(0);
		MPart part = stack.getChildren().get(0);