File: CollectionAssertTest.cs

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// ****************************************************************
// This is free software licensed under the NUnit license. You
// may obtain a copy of the license as well as information regarding
// copyright ownership at http://nunit.org.
// ****************************************************************

using System;
using System.Collections;
#if NET_3_5 || NET_4_0 || NET_4_5
using System.Linq;
#endif

namespace NUnit.Framework.Tests
{
	/// <summary>
	/// Test Library for the NUnit CollectionAssert class.
	/// </summary>
	[TestFixture()]
	public class CollectionAssertTest : MessageChecker
	{
		#region AllItemsAreInstancesOfType
		[Test()]
		public void ItemsOfType()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add("z");
			CollectionAssert.AllItemsAreInstancesOfType(al,typeof(string));
        }

		[Test,ExpectedException(typeof(AssertionException))]
		public void ItemsOfTypeFailure()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add(new object());

			expectedMessage =
				"  Expected: all items instance of <System.String>" + Environment.NewLine +
				"  But was:  < \"x\", \"y\", <System.Object> >" + Environment.NewLine;
			CollectionAssert.AllItemsAreInstancesOfType(al,typeof(string));
		}
		#endregion

		#region AllItemsAreNotNull
		[Test()]
		public void ItemsNotNull()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add("z");

			CollectionAssert.AllItemsAreNotNull(al);
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void ItemsNotNullFailure()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add(null);
			al.Add("z");

			expectedMessage =
                "  Expected: all items not null" + Environment.NewLine +
                "  But was:  < \"x\", null, \"z\" >" + Environment.NewLine;
			CollectionAssert.AllItemsAreNotNull(al);
		}
		#endregion

		#region AllItemsAreUnique

		[Test]
		public void Unique_WithObjects()
		{
			CollectionAssert.AllItemsAreUnique(
				new ICollectionAdapter( new object(), new object(), new object() ) );
		}

		[Test]
		public void Unique_WithStrings()
		{
			CollectionAssert.AllItemsAreUnique( new ICollectionAdapter( "x", "y", "z" ) );
		}

		[Test]
		public void Unique_WithNull()
		{
			CollectionAssert.AllItemsAreUnique(	new ICollectionAdapter( "x", "y", null, "z" ) );
		}

		[Test,ExpectedException(typeof(AssertionException))]
		public void UniqueFailure()
		{
			expectedMessage =
                "  Expected: all items unique" + Environment.NewLine +
                "  But was:  < \"x\", \"y\", \"x\" >" + Environment.NewLine;
			CollectionAssert.AllItemsAreUnique( new ICollectionAdapter( "x", "y", "x" ) );
		}

		[Test,ExpectedException(typeof(AssertionException))]
		public void UniqueFailure_WithTwoNulls()
		{
			CollectionAssert.AllItemsAreUnique( new ICollectionAdapter( "x", null, "y", null, "z" ) );
		}

		#endregion

		#region AreEqual

		[Test]
		public void AreEqual()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");
			set2.Add("x");
			set2.Add("y");
			set2.Add("z");

			CollectionAssert.AreEqual(set1,set2);
			CollectionAssert.AreEqual(set1,set2,new TestComparer());

			Assert.AreEqual(set1,set2);
		}

		[Test,ExpectedException(typeof(AssertionException))]
		public void AreEqualFailCount()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");
			set2.Add("x");
			set2.Add("y");
			set2.Add("z");
			set2.Add("a");

			expectedMessage =
                "  Expected is <System.Collections.ArrayList> with 3 elements, actual is <System.Collections.ArrayList> with 4 elements" + Environment.NewLine +
                "  Values differ at index [3]" + Environment.NewLine +
                "  Extra:    < \"a\" >";
			CollectionAssert.AreEqual(set1,set2,new TestComparer());
		}

        [Test, ExpectedException(typeof(AssertionException))]
		public void AreEqualFail()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");
			set2.Add("x");
			set2.Add("y");
			set2.Add("a");

			expectedMessage =
                "  Expected and actual are both <System.Collections.ArrayList> with 3 elements" + Environment.NewLine +
                "  Values differ at index [2]" + Environment.NewLine +
                "  String lengths are both 1. Strings differ at index 0." + Environment.NewLine +
                "  Expected: \"z\"" + Environment.NewLine +
                "  But was:  \"a\"" + Environment.NewLine +
                "  -----------^" + Environment.NewLine;

			CollectionAssert.AreEqual(set1,set2,new TestComparer());
		}

		[Test]
		public void AreEqual_HandlesNull()
		{
			object[] set1 = new object[3];
			object[] set2 = new object[3];

			CollectionAssert.AreEqual(set1,set2);
			CollectionAssert.AreEqual(set1,set2,new TestComparer());
		}

		[Test]
		public void EnsureComparerIsUsed()
		{
			// Create two collections
			int[] array1 = new int[2];
			int[] array2 = new int[2];

			array1[0] = 4;
			array1[1] = 5;

			array2[0] = 99;
			array2[1] = -99;

			CollectionAssert.AreEqual(array1, array2, new AlwaysEqualComparer());
        }

#if CLR_2_0 || CLR_4_0
        [Test]
        public void AreEqual_UsingIterator()
        {
            int[] array = new int[] { 1, 2, 3 };

            CollectionAssert.AreEqual(array, CountToThree());
        }

        IEnumerable CountToThree()
        {
            yield return 1;
            yield return 2;
            yield return 3;
        }

        [Test]
        public void AreEqual_UsingIterator_Fails()
        {
            int[] array = new int[] { 1, 3, 5 };

			Assert.That(
            	delegate { CollectionAssert.AreEqual(array, CountToThree()); },
			    Throws.TypeOf<AssertionException>()
					.With.Message.EndsWith("Expected: 3" + Environment.NewLine + "  But was:  2" + Environment.NewLine));
        }
#endif

#if NET_3_5 || CLR_4_0
        [Test, Platform("Net-3.5,Mono-3.5,Net-4.0,Mono-4.0")]
        public void AreEqual_UsingLinqQuery()
        {
            int[] array = new int[] { 1, 2, 3 };

            CollectionAssert.AreEqual(array, array.Select((item) => item));
        }

        [Test, Platform("Net-3.5,Mono-3.5,Net-4.0,Mono-4.0")]
        public void AreEqual_UsingLinqQuery_Fails()
        {
            int[] array = new int[] { 1, 2, 3 };

			Assert.That(
				delegate { CollectionAssert.AreEqual(array, array.Select((item) => item * 2)); },
				Throws.TypeOf<AssertionException>()
					.With.Message.EndsWith("Expected: 1" + Environment.NewLine + "  But was:  2" + Environment.NewLine));
        }
#endif
        #endregion

        #region AreEquivalent

        [Test]
		public void Equivalent()
		{
			ICollection set1 = new ICollectionAdapter( "x", "y", "z" );
			ICollection set2 = new ICollectionAdapter( "z", "y", "x" );

			CollectionAssert.AreEquivalent(set1,set2);
		}

        [Test, ExpectedException(typeof(AssertionException))]
        public void EquivalentFailOne()
		{
			ICollection set1 = new ICollectionAdapter( "x", "y", "z" );
			ICollection set2 = new ICollectionAdapter( "x", "y", "x" );

			expectedMessage =
                "  Expected: equivalent to < \"x\", \"y\", \"z\" >" + Environment.NewLine +
                "  But was:  < \"x\", \"y\", \"x\" >" + Environment.NewLine;
			CollectionAssert.AreEquivalent(set1,set2);
		}

        [Test, ExpectedException(typeof(AssertionException))]
        public void EquivalentFailTwo()
		{
			ICollection set1 = new ICollectionAdapter( "x", "y", "x" );
			ICollection set2 = new ICollectionAdapter( "x", "y", "z" );
			
			expectedMessage =
                "  Expected: equivalent to < \"x\", \"y\", \"x\" >" + Environment.NewLine +
                "  But was:  < \"x\", \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.AreEquivalent(set1,set2);
		}

        [Test]
		public void AreEquivalentHandlesNull()
		{
			ICollection set1 = new ICollectionAdapter( null, "x", null, "z" );
			ICollection set2 = new ICollectionAdapter( "z", null, "x", null );
			
			CollectionAssert.AreEquivalent(set1,set2);
		}
		#endregion

		#region AreNotEqual

		[Test]
		public void AreNotEqual()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");
			set2.Add("x");
			set2.Add("y");
			set2.Add("x");

			CollectionAssert.AreNotEqual(set1,set2);
			CollectionAssert.AreNotEqual(set1,set2,new TestComparer());
			CollectionAssert.AreNotEqual(set1,set2,"test");
			CollectionAssert.AreNotEqual(set1,set2,new TestComparer(),"test");
			CollectionAssert.AreNotEqual(set1,set2,"test {0}","1");
			CollectionAssert.AreNotEqual(set1,set2,new TestComparer(),"test {0}","1");
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void AreNotEqual_Fails()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");
			set2.Add("x");
			set2.Add("y");
			set2.Add("z");

			expectedMessage = 
				"  Expected: not < \"x\", \"y\", \"z\" >" + Environment.NewLine +
				"  But was:  < \"x\", \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.AreNotEqual(set1,set2);
		}

		[Test]
		public void AreNotEqual_HandlesNull()
		{
			object[] set1 = new object[3];
			ArrayList set2 = new ArrayList();
			set2.Add("x");
			set2.Add("y");
			set2.Add("z");

			CollectionAssert.AreNotEqual(set1,set2);
			CollectionAssert.AreNotEqual(set1,set2,new TestComparer());
		}

		#endregion

		#region AreNotEquivalent

		[Test]
		public void NotEquivalent()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");

			set2.Add("x");
			set2.Add("y");
			set2.Add("x");

			CollectionAssert.AreNotEquivalent(set1,set2);
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void NotEquivalent_Fails()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");

			set2.Add("x");
			set2.Add("z");
			set2.Add("y");

			expectedMessage =
				"  Expected: not equivalent to < \"x\", \"y\", \"z\" >" + Environment.NewLine +
				"  But was:  < \"x\", \"z\", \"y\" >" + Environment.NewLine;
			CollectionAssert.AreNotEquivalent(set1,set2);
		}

		[Test]
		public void NotEquivalentHandlesNull()
		{
			ArrayList set1 = new ArrayList();
			ArrayList set2 = new ArrayList();
			
			set1.Add("x");
			set1.Add(null);
			set1.Add("z");

			set2.Add("x");
			set2.Add(null);
			set2.Add("x");

			CollectionAssert.AreNotEquivalent(set1,set2);
		}
		#endregion

		#region Contains
		[Test]
		public void Contains_IList()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add("z");

			CollectionAssert.Contains(al,"x");
		}

		[Test]
		public void Contains_ICollection()
		{
			ICollectionAdapter ca = new ICollectionAdapter( new string[] { "x", "y", "z" } );

			CollectionAssert.Contains(ca,"x");
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void ContainsFails_ILIst()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add("z");

			expectedMessage =
				"  Expected: collection containing \"a\"" + Environment.NewLine +
				"  But was:  < \"x\", \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.Contains(al,"a");
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void ContainsFails_ICollection()
		{
			ICollectionAdapter ca = new ICollectionAdapter( new string[] { "x", "y", "z" } );

			expectedMessage =
				"  Expected: collection containing \"a\"" + Environment.NewLine +
				"  But was:  < \"x\", \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.Contains(ca,"a");
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void ContainsFails_EmptyIList()
		{
			ArrayList al = new ArrayList();

			expectedMessage =
				"  Expected: collection containing \"x\"" + Environment.NewLine +
				"  But was:  <empty>" + Environment.NewLine;
			CollectionAssert.Contains(al,"x");
		}

		[Test, ExpectedException(typeof(AssertionException))]
		public void ContainsFails_EmptyICollection()
		{
			ICollectionAdapter ca = new ICollectionAdapter( new object[0] );

			expectedMessage =
				"  Expected: collection containing \"x\"" + Environment.NewLine +
				"  But was:  <empty>" + Environment.NewLine;
			CollectionAssert.Contains(ca,"x");
		}

		[Test]
		public void ContainsNull_IList()
		{
			Object[] oa = new object[] { 1, 2, 3, null, 4, 5 };
			CollectionAssert.Contains( oa, null );
		}

		[Test]
		public void ContainsNull_ICollection()
		{
			ICollectionAdapter ca = new ICollectionAdapter( new object[] { 1, 2, 3, null, 4, 5 } );
			CollectionAssert.Contains( ca, null );
		}
		#endregion

		#region DoesNotContain
		[Test]
		public void DoesNotContain()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add("z");

			CollectionAssert.DoesNotContain(al,"a");
		}

		[Test]
		public void DoesNotContain_Empty()
		{
			ArrayList al = new ArrayList();

			CollectionAssert.DoesNotContain(al,"x");
		}

		[Test,ExpectedException(typeof(AssertionException))]
		public void DoesNotContain_Fails()
		{
			ArrayList al = new ArrayList();
			al.Add("x");
			al.Add("y");
			al.Add("z");

			expectedMessage = 
				"  Expected: not collection containing \"y\"" + Environment.NewLine +
				"  But was:  < \"x\", \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.DoesNotContain(al,"y");
		}
		#endregion

		#region IsSubsetOf
		[Test]
		public void IsSubsetOf()
		{
			ArrayList set1 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");

			ArrayList set2 = new ArrayList();
			set2.Add("y");
			set2.Add("z");

			CollectionAssert.IsSubsetOf(set2,set1);
            Expect(set2, SubsetOf(set1));
		}

		[Test,ExpectedException(typeof(AssertionException))]
		public void IsSubsetOf_Fails()
		{
			ArrayList set1 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");

			ArrayList set2 = new ArrayList();
			set2.Add("y");
			set2.Add("z");
			set2.Add("a");

			expectedMessage =
				"  Expected: subset of < \"y\", \"z\", \"a\" >" + Environment.NewLine +
				"  But was:  < \"x\", \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.IsSubsetOf(set1,set2);
		}

		[Test]
		public void IsSubsetOfHandlesNull()
		{
			ArrayList set1 = new ArrayList();
			set1.Add("x");
			set1.Add(null);
			set1.Add("z");

			ArrayList set2 = new ArrayList();
			set2.Add(null);
			set2.Add("z");

			CollectionAssert.IsSubsetOf(set2,set1);
            Expect(set2, SubsetOf(set1));
		}
		#endregion

		#region IsNotSubsetOf
		[Test]
		public void IsNotSubsetOf()
		{
			ArrayList set1 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");

			ArrayList set2 = new ArrayList();
			set1.Add("y");
			set1.Add("z");
			set2.Add("a");

			CollectionAssert.IsNotSubsetOf(set1,set2);
            Expect(set1, Not.SubsetOf(set2));
		}

		[Test,ExpectedException(typeof(AssertionException))]
		public void IsNotSubsetOf_Fails()
		{
			ArrayList set1 = new ArrayList();
			set1.Add("x");
			set1.Add("y");
			set1.Add("z");

			ArrayList set2 = new ArrayList();
			set2.Add("y");
			set2.Add("z");

			expectedMessage =
				"  Expected: not subset of < \"x\", \"y\", \"z\" >" + Environment.NewLine +
				"  But was:  < \"y\", \"z\" >" + Environment.NewLine;
			CollectionAssert.IsNotSubsetOf(set2,set1);
		}
		
		[Test]
		public void IsNotSubsetOfHandlesNull()
		{
			ArrayList set1 = new ArrayList();
			set1.Add("x");
			set1.Add(null);
			set1.Add("z");

			ArrayList set2 = new ArrayList();
			set1.Add(null);
			set1.Add("z");
			set2.Add("a");

			CollectionAssert.IsNotSubsetOf(set1,set2);
		}
		#endregion

        #region IsOrdered

        [Test]
        public void IsOrdered()
        {
            ArrayList al = new ArrayList();
            al.Add("x");
            al.Add("y");
            al.Add("z");

            CollectionAssert.IsOrdered(al);
        }

        [Test, ExpectedException(typeof(AssertionException))]
        public void IsOrdered_Fails()
        {
            ArrayList al = new ArrayList();
            al.Add("x");
            al.Add("z");
            al.Add("y");

            expectedMessage =
                "  Expected: collection ordered" + Environment.NewLine +
                "  But was:  < \"x\", \"z\", \"y\" >" + Environment.NewLine;

            CollectionAssert.IsOrdered(al);
        }

        [Test]
        public void IsOrdered_Allows_adjacent_equal_values()
        {
            ArrayList al = new ArrayList();
            al.Add("x");
            al.Add("x");
            al.Add("z");

            CollectionAssert.IsOrdered(al);
        }

        [Test, ExpectedException(typeof(ArgumentNullException),
            ExpectedMessage = "index 1", MatchType = MessageMatch.Contains)]
        public void IsOrdered_Handles_null()
        {
            ArrayList al = new ArrayList();
            al.Add("x");
            al.Add(null);
            al.Add("z");

            CollectionAssert.IsOrdered(al);
        }

        [Test, ExpectedException(typeof(ArgumentException))]
        public void IsOrdered_ContainedTypesMustBeCompatible()
        {
            ArrayList al = new ArrayList();
            al.Add(1);
            al.Add("x");

            CollectionAssert.IsOrdered(al);
        }

        [Test, ExpectedException(typeof(ArgumentException))]
        public void IsOrdered_TypesMustImplementIComparable()
        {
            ArrayList al = new ArrayList();
            al.Add(new object());
            al.Add(new object());

            CollectionAssert.IsOrdered(al);
        }

        [Test]
        public void IsOrdered_Handles_custom_comparison()
        {
            ArrayList al = new ArrayList();
            al.Add(new object());
            al.Add(new object());

            CollectionAssert.IsOrdered(al, new AlwaysEqualComparer());
        }

        [Test]
        public void IsOrdered_Handles_custom_comparison2()
        {
            ArrayList al = new ArrayList();
            al.Add(2);
            al.Add(1);

            CollectionAssert.IsOrdered(al, new TestComparer());
        }

        #endregion
    }

	public class TestComparer : IComparer
	{
        public bool Called = false;
        
        #region IComparer Members
		public int Compare(object x, object y)
		{
            Called = true;

			if ( x == null && y == null )
				return 0;

			if ( x == null || y == null )
				return -1;

			if (x.Equals(y))
				return 0;

			return -1;
		}
		#endregion
	}

	public class AlwaysEqualComparer : IComparer
	{
        public bool Called = false;

		int IComparer.Compare(object x, object y)
		{
            Called = true;

			// This comparer ALWAYS returns zero (equal)!
			return 0;
		}
	}
}