v2 v3   Warning

xUnit2005

"Do not use identity check on value type"

Cause

A violation of this rule occurs when two value type objects are compared using Assert.Same or Assert.NotSame.

Reason for rule

Assert.Same and Assert.NotSame both use Object.ReferenceEquals to compare objects. This always fails for value types since the values will be boxed before they are passed to the method, creating two different references (even if the values are the equal).

How to fix violations

To fix a violation of this rule, use Assert.Equal or Assert.NotEqual instead.

Examples

Violates

using System;
using Xunit;

public class xUnit2005
{
    [Fact]
    public void TestMethod()
    {
        var result = DateTime.Now;

        Assert.Same(new DateTime(2017, 1, 1), result);
    }
}

Does not violate

using System;
using Xunit;

public class xUnit2005
{
    [Fact]
    public void TestMethod()
    {
        var result = DateTime.Now;

        Assert.Equal(new DateTime(2017, 1, 1), result);
    }
}