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

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;


public class SimpleTest {

    private static MergeSort sorter;

    @BeforeClass
    public static void init() {
        sorter = new NonRecursiveMergeSort();
    }

    @Test
    public void test1() {
        List<Integer> input = Arrays.asList(5, -8, 3, 1, 2, -8, 7, 9, 11, -6);
        sorter.sort(input);
        Assert.assertEquals(Arrays.asList(-8, -8, -6, 1, 2, 3, 5, 7, 9, 11), input);
    }

    @Test
    public void test2() {
        List<Integer> input = Arrays.asList(5, 7, 1, 2);
        sorter.sort(input);
        Assert.assertEquals(Arrays.asList(1, 2, 5, 7), input);
    }

    @Test
    public void test3() {
        List<Integer> input = Arrays.asList(3, 4, 5, 6, 7, 8);
        sorter.sort(input);
        Assert.assertEquals(Arrays.asList(3, 4, 5, 6, 7, 8), input);
    }

    @Test
    public void testEmpty() {
        List<Integer> input = new ArrayList<>();
        sorter.sort(input);
        Assert.assertEquals(Collections.emptyList(), input);
    }
    
}