/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.math4.exception.util;

import java.util.List;
import java.util.ArrayList;

import org.apache.commons.math4.exception.util.ArgUtils;
import org.junit.Assert;
import org.junit.Test;

/**
 * Test for {@link ArgUtils}.
 *
 */
public class ArgUtilsTest {
    @Test
    public void testFlatten() {
        final List<Object> orig = new ArrayList<>();

        final Object[] struct = new Object[] {
            new Object[] {
                new Object[] {
                    create(orig),
                    create(orig),
                },
                create(orig),
                new Object[] {
                    create(orig),
                }
            },
            create(orig),
            new Object[] {
                create(orig),
                new Object[] {
                    create(orig),
                    create(orig),
                }
            },
            create(orig),
        };

        Object[] flat = ArgUtils.flatten(struct);
        Assert.assertEquals(flat.length, orig.size());

        for (int i = 0, max = orig.size(); i < max; i++) {
            Assert.assertEquals(orig.get(i), flat[i]);
        }
    }

    /**
     * Create and store an {@code Object}.
     *
     * @param list List to store to.
     * @return the stored object.
     */
    private Object create(List<Object> list) {
        final Object o = new Object();
        list.add(o);
        return o;
    }
}