CollectionAssert.That Property
Definition
Important
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Gets the singleton instance of the CollectionAssert functionality.
public:
static property Microsoft::VisualStudio::TestTools::UnitTesting::CollectionAssert ^ That { Microsoft::VisualStudio::TestTools::UnitTesting::CollectionAssert ^ get(); };public static Microsoft.VisualStudio.TestTools.UnitTesting.CollectionAssert That { get; }[System.Runtime.CompilerServices.Nullable(1)]
public static Microsoft.VisualStudio.TestTools.UnitTesting.CollectionAssert That { get; }static member That : Microsoft.VisualStudio.TestTools.UnitTesting.CollectionAssert[<System.Runtime.CompilerServices.Nullable(1)>]
static member That : Microsoft.VisualStudio.TestTools.UnitTesting.CollectionAssertPublic Shared ReadOnly Property That As CollectionAssertProperty Value
- Attributes
Examples
The following example defines a custom AreEqualUnordered assertion as an extension method
on CollectionAssert and invokes it through CollectionAssert.That:
using System.Collections.Generic;
using System.Linq;
using Microsoft.VisualStudio.TestTools.UnitTesting;
public static class CustomCollectionAssertExtensions
{
public static void AreEqualUnordered<T>(this CollectionAssert collectionAssert, IEnumerable<T> expected, IEnumerable<T> actual)
{
if (!expected.OrderBy(x => x).SequenceEqual(actual.OrderBy(x => x)))
{
throw new AssertFailedException("CollectionAssert.That.AreEqualUnordered failed. Collections do not contain the same elements.");
}
}
}
[TestClass]
public class SetTests
{
[TestMethod]
public void Items_MatchRegardlessOfOrder()
{
CollectionAssert.That.AreEqualUnordered(new[] { 1, 2, 3 }, new[] { 3, 1, 2 });
}
}
Remarks
Users can use this to plug-in custom assertions through C# extension methods. For instance, the signature of a custom assertion provider could be public static void AreEqualUnordered(this CollectionAssert customAssert, ICollection expected, ICollection actual) and the call-site would be CollectionAssert.That.AreEqualUnordered(list1, list2);.
For new custom assertions, prefer extending That instead, because CollectionAssert is likely to be deprecated in a future release. For more information, see Extension hooks on StringAssert and CollectionAssert.
