bundles/org.eclipse.equinox.console.tests/src/org/eclipse/equinox/console/common/HistoryHolderTests.java

/*******************************************************************************
 * Copyright (c) 2011 SAP AG
 *
 * 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:
 *    Lazar Kirchev, SAP AG - initial contribution
 ******************************************************************************/

package org.eclipse.equinox.console.common;

import org.junit.Assert;
import org.junit.Test;


public class HistoryHolderTests {

	@Test
	public void test() {
		HistoryHolder historyHolder = new HistoryHolder();
		byte[] line1 = new byte[] { 'a', 'b', 'c', 'd' };
		byte[] line2 = new byte[] { 'x', 'y', 'z' };
		byte[] line3 = new byte[] { 'k', 'l', 'm', 'n' };

		historyHolder.add(line1);
		historyHolder.add(line2);
		historyHolder.add(line3);

		byte[] first = historyHolder.first();
		Assert.assertEquals("Wrong length of first member", line1.length, first.length);
		Assert.assertArrayEquals("Wrong first member", line1, first);

		byte[] last = historyHolder.last();
		Assert.assertEquals("Wrong length of last member", line3.length, last.length);
		Assert.assertArrayEquals("Wrong last member", line3, last);

		byte[] prev = historyHolder.prev();
		Assert.assertEquals("Wrong length of previous member", line2.length, prev.length);
		Assert.assertArrayEquals("Wrong previous member", line2, prev);

		byte[] next = historyHolder.next();
		Assert.assertEquals("Wrong length of next member", line3.length, next.length);
		Assert.assertArrayEquals("Wrong next member", line3, next);

		historyHolder.first();
		historyHolder.add(new byte[] {});
		byte[] current = historyHolder.prev();
		Assert.assertEquals("Wrong length of next member", line3.length, current.length);
		Assert.assertArrayEquals("Wrong next member", line3, current);

		historyHolder.first();
		historyHolder.add(line1);
		current = historyHolder.prev();
		Assert.assertEquals("Wrong length of next member", line1.length, current.length);
		Assert.assertArrayEquals("Wrong next member", line1, current);
		Assert.assertArrayEquals("Second line should now be first", line2, historyHolder.first());

		historyHolder.reset();
		Assert.assertNull("History should be empty", historyHolder.first());
		Assert.assertNull("History should be empty", historyHolder.last());
		Assert.assertNull("History should be empty", historyHolder.next());
		Assert.assertNull("History should be empty", historyHolder.prev());
	}

}