using System;
using System.Collections.Generic;
using System.Text;
using Xunit;

namespace XUnitTest.Collections;

public class CollectionHelperTests
{
    [Fact]
    public void ToArrayTest()
    {
        var vs = new[] { 12, 34, 56, 78, 90 };
        var list = new List<Int32>(vs);
        var list2 = list as IList<Int32>;

        var vs2 = list2.ToArray();
        Assert.Equal(vs.Length, vs2.Length);
        Assert.Equal(vs[0], vs2[0]);
        Assert.Equal(vs[1], vs2[1]);
        Assert.Equal(vs[2], vs2[2]);
        Assert.Equal(vs[3], vs2[3]);
        Assert.Equal(vs[4], vs2[4]);

        //var vs3 = list2.ToArray(2);
        //Assert.Equal(vs.Length + 2, vs3.Length);
        //Assert.Equal(vs[0], vs3[2]);
        //Assert.Equal(vs[1], vs3[3]);
        //Assert.Equal(vs[2], vs3[4]);
        //Assert.Equal(vs[3], vs3[5]);
        //Assert.Equal(vs[4], vs3[6]);
    }

    [Fact]
    public void CheckNullable()
    {
        var dic = new Dictionary<String, String?>()
        {
            ["a"] = "a",
            ["b"] = null,
            ["c"] = "c"
        };

        var rs = dic is IDictionary<String, String>;
        Assert.True(rs);

        rs = dic is IDictionary<String, String?>;
        Assert.True(rs);
    }
}