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

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

using System.Collections.Generic;

using Xunit;

namespace System.Linq.Tests

{

public class UnionTests : EnumerableBasedTests

{

[Fact]

public void CustomComparer()

{

string[] first = { "Bob", "Robert", "Tim", "Matt", "miT" };

string[] second = { "ttaM", "Charlie", "Bbo" };

string[] expected = { "Bob", "Robert", "Tim", "Matt", "Charlie" };

var comparer = new AnagramEqualityComparer();

Assert.Equal(expected, first.AsQueryable().Union(second.AsQueryable(), comparer), comparer);

}

[Fact]

public void FirstNullCustomComparer()

{

IQueryable<string> first = null;

string[] second = { "ttaM", "Charlie", "Bbo" };

var ane = Assert.Throws<ArgumentNullException>("source1", () => first.Union(second.AsQueryable(), new AnagramEqualityComparer()));

}

[Fact]

public void SecondNullCustomComparer()

{

string[] first = { "Bob", "Robert", "Tim", "Matt", "miT" };

IQueryable<string> second = null;

var ane = Assert.Throws<ArgumentNullException>("source2", () => first.AsQueryable().Union(second, new AnagramEqualityComparer()));

}

[Fact]

public void FirstNullNoComparer()

{

IQueryable<string> first = null;

string[] second = { "ttaM", "Charlie", "Bbo" };

var ane = Assert.Throws<ArgumentNullException>("source1", () => first.Union(second.AsQueryable()));

}

[Fact]

public void SecondNullNoComparer()

{

string[] first = { "Bob", "Robert", "Tim", "Matt", "miT" };

IQueryable<string> second = null;

var ane = Assert.Throws<ArgumentNullException>("source2", () => first.AsQueryable().Union(second));

}

[Fact]

public void CommonElementsShared()

{

int[] first = { 1, 2, 3, 4, 5, 6 };

int[] second = { 6, 7, 7, 7, 8, 1 };

int[] expected = { 1, 2, 3, 4, 5, 6, 7, 8 };

Assert.Equal(expected, first.AsQueryable().Union(second.AsQueryable()));

}

[Fact]

public void Union1()

{

var count = (new int[] { 0, 1, 2 }).AsQueryable().Union((new int[] { 1, 2, 3 }).AsQueryable()).Count();

Assert.Equal(4, count);

}

[Fact]

public void Union2()

{

var count = (new int[] { 0, 1, 2 }).AsQueryable().Union((new int[] { 1, 2, 3 }).AsQueryable(), EqualityComparer<int>.Default).Count();

Assert.Equal(4, count);

}

}

}