Bug 126658 [CommonNavigator] [DND] Complete definition of DND API
tests/org.eclipse.ui.tests.navigator/src/org/eclipse/ui/tests/navigator/INavigatorContentServiceTests.java
}
	public void testResourceExtensionVisibility() {
		assertTrue("The test extension should be visible.", contentService
				.getViewerDescriptor().isVisibleContentExtension(
						RESOURCE_EXTENSION_ID));
	}
	public void testVisibleExtensionIds() {
		String[] visibleIds = contentService.getVisibleExtensionIds();
		assertEquals("There should be two visible extensions.", 2,
				visibleIds.length);
		for (int i = 0; i < visibleIds.length; i++) {
			if (!TEST_EXTENSION_ID.equals(visibleIds[i])
					&& !RESOURCE_EXTENSION_ID.equals(visibleIds[i])) {
				assertTrue("The extension id is invalid:" + visibleIds[i],
						false);
			}
		}
		INavigatorContentDescriptor[] visibleDescriptors = contentService
				.getVisibleExtensions();
		for (int i = 0; i < visibleIds.length; i++) {
			if (!TEST_EXTENSION_ID.equals(visibleDescriptors[i].getId())
					&& !RESOURCE_EXTENSION_ID.equals(visibleDescriptors[i]
							.getId())) {
				assertTrue("The extension id is invalid:"
						+ visibleDescriptors[i].getId(), false);
			}
		}
	}
}