tests/org.eclipse.e4.ui.tests.css.swt/src/org/eclipse/e4/ui/tests/css/swt/DescendentTest.java

/*******************************************************************************
 * Copyright (c) 2013, 2014 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Thibault Le Ouay <thibaultleouay@gmail.com> - Bug 443094
 *******************************************************************************/
package org.eclipse.e4.ui.tests.css.swt;

import static org.junit.Assert.assertEquals;

import org.eclipse.e4.ui.css.swt.dom.WidgetElement;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Shell;
import org.junit.Test;

public class DescendentTest extends CSSSWTTestCase {

	static final RGB RED = new RGB(255, 0, 0);
	static final RGB GREEN = new RGB(0, 255, 0);
	static final RGB BLUE = new RGB(0, 0, 255);
	static final RGB WHITE = new RGB(255, 255, 255);
	static final RGB BLACK = new RGB(0, 0, 0);

	protected Button[] createTestWidgets(String styleSheet) {

		engine = createEngine(styleSheet, display);

		// Create widgets
		Shell shell = new Shell(display, SWT.SHELL_TRIM);
		FillLayout layout = new FillLayout();
		shell.setLayout(layout);
		Composite panelA = new Composite(shell, SWT.NONE);
		panelA.setLayout(new FillLayout());
		Composite panelB = new Composite(shell, SWT.NONE);
		panelB.setLayout(new FillLayout());

		Button buttonA = new Button(panelA, SWT.NONE);
		Button buttonB = new Button(panelB, SWT.NONE);
		Button buttonC = new Button(shell, SWT.NONE);

		engine.applyStyles(shell, true);
		return new Button[] {buttonA, buttonB, buttonC};
	}

	@Test
	public void testDescendentSpecificity() {
		Button[] buttons = createTestWidgets(
				"Composite.special Button { background: #FF0000}\n" +  //specificity a=1 b=0 c=1 = 101
						"Composite Button { background: #00FF00}\n" + //specificity a=0 b=0 c=2 = 002
						"Composite.extraordinary Button { background: #FFFFFF}\n" + //specificity a=0 b=0 c=2 = 002
						"#parent Button { background: #000000}\n" + //specificity a=0 b=0 c=2 = 002
				"Button { background: #0000FF}");  //specificity a=0 b=0 c=1 = 001

		Button buttonA = buttons[0];
		Button buttonB = buttons[1];
		Button buttonC = buttons[2];

		WidgetElement.setCSSClass(buttonA.getParent(), "special");
		engine.applyStyles(buttonA.getShell(), true);

		assertEquals(RED, buttonA.getBackground().getRGB());
		assertEquals(GREEN, buttonB.getBackground().getRGB());
		assertEquals(BLUE, buttonC.getBackground().getRGB());

		WidgetElement.setCSSClass(buttonA.getParent(), "extraordinary");
		WidgetElement.setID(buttonB.getParent(), "parent");

		engine.applyStyles(buttonA.getShell(), true);
		assertEquals(WHITE, buttonA.getBackground().getRGB());
		assertEquals(BLACK, buttonB.getBackground().getRGB());
	}
}