AStarGridTest.java

/*
 * The MIT License (MIT)
 *
 * FXGL - JavaFX Game Library
 *
 * Copyright (c) 2015-2017 AlmasB (almaslvl@gmail.com)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.almasb.fxgl.ai.pathfinding;

import org.junit.Before;
import org.junit.Test;

import java.util.List;
import java.util.Optional;

import static org.hamcrest.CoreMatchers.anyOf;
import static org.hamcrest.CoreMatchers.is;
import static org.junit.Assert.*;

public class AStarGridTest {

    private static final int GRID_SIZE = 20;
    private AStarGrid grid;

    @Before
    public void setUp() {
        grid = new AStarGrid(GRID_SIZE, GRID_SIZE);
    }

    @Test
    public void testValidity() {
        int count = 0;

        try {
            new AStarGrid(-1, 5);
        } catch (IllegalArgumentException e) {
            count++;
        }

        assertThat(count, is(1));

        try {
            new AStarGrid(5, -1);
        } catch (IllegalArgumentException e) {
            count++;
        }

        assertThat(count, is(2));
    }

    @Test
    public void testIsWithin() throws Exception {
        for (int i = 0; i < GRID_SIZE; i++) {
            for (int j = 0; j < GRID_SIZE; j++) {
                assertTrue(grid.isWithin(j, i));
            }
        }

        assertFalse(grid.isWithin(GRID_SIZE, 0));
        assertFalse(grid.isWithin(0, GRID_SIZE));
    }

    @Test
    public void testGetNodeState() throws Exception {
        for (int i = 0; i < GRID_SIZE; i++) {
            for (int j = 0; j < GRID_SIZE; j++) {
                assertEquals(NodeState.WALKABLE, grid.getNodeState(j, i));
            }
        }
    }

    @Test
    public void testRandomNode() {
        Optional<AStarNode> maybe = grid.getRandomNode(node -> node.getX() < 3 && node.getY() > 15);
        assertThat(maybe.isPresent(), is(true));

        AStarNode node = maybe.get();
        assertThat(node.getX(), anyOf(is(0), is(1), is(2)));
        assertThat(node.getY(), anyOf(is(16), is(17), is(18), is(19)));
    }

    @Test
    public void testGetPath() throws Exception {
        List<AStarNode> path = grid.getPath(3, 0, 5, 0);
        assertPathEquals(path,
                4, 0,
                5, 0);

        for (int i = 0; i <= 4; i++)
            grid.setNodeState(4, i, NodeState.NOT_WALKABLE);

        path = grid.getPath(3, 0, 5, 0);
        assertPathEquals(path,
                3, 1,
                3, 2,
                3, 3,
                3, 4,
                3, 5,
                4, 5,
                5, 5,
                5, 4,
                5, 3,
                5, 2,
                5, 1,
                5, 0);

        for (int i = 0; i <= 19; i++)
            grid.setNodeState(4, i, NodeState.NOT_WALKABLE);

        path = grid.getPath(3, 0, 5, 0);
        assertTrue(path.isEmpty());
    }

    private void assertPathEquals(List<AStarNode> path, int... points) {
        assertEquals(points.length / 2, path.size());

        int i = 0;
        for (AStarNode node : path) {
            assertEquals(points[i++], node.getX());
            assertEquals(points[i++], node.getY());
        }

        assertEquals(points.length, i);
    }
}