// Copyright (c) Microsoft. All rights reserved.

// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using System;

using Xunit;

namespace System.Linq.Tests

{

public class OfTypeTests : EnumerableBasedTests

{

[Fact]

public void EmptySource()

{

object[] source = { };

Assert.Empty(source.AsQueryable().OfType<int>());

}

[Fact]

public void HeterogenousSourceOnlyFirstOfType()

{

object[] source = { 10, "Hello", 3.5, "Test" };

int[] expected = { 10 };

Assert.Equal(expected, source.AsQueryable().OfType<int>());

}

[Fact]

public void NullSource()

{

Assert.Throws<ArgumentNullException>("source", () => ((IQueryable<object>)null).OfType<string>());

}

[Fact]

public void OfType()

{

var count = (new object[] { 0, (long)1, 2 }).AsQueryable().OfType<int>().Count();

Assert.Equal(2, count);

}

}

}