[ACCEPTED]-NUnit Assert.Equals What am I missing?-nunit

Use Assert.AreEqual(a, b) for value types, Assert.AreSame(a, b) for reference types. http://www.nunit.org/index.php?p=identityAsserts&r=2.2.7

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You are definitely correct. I was wrestling 23 with a similar problem earlier today, until I found your 22 post and am now sure, that NUnit IsEqualTo() does 21 not consistently call the Equals overrides 20 provided.

I say consistently, because sometimes 19 it does. As a matter of fact I have two 18 classes. The second one derived from the 17 first. When I call Is.EqualTo() on instances 16 of the first, NUnit calls the Equals overrides, for 15 instances of the second it does not.

While 14 that is very peculiar, I have no time to 13 investigate further into what is going on.

People 12 with similar problems or solutions should 11 definitely post about it, as this is a very 10 annoying thing and actually had me doubt 9 the validity of my tests.

In the meantime 8 I created the following Affirm class, which 7 calls the Equals overrides for sure (I checked 6 it). It uses NUnit to do a simple equality 5 Assert instead of Is.EqualTo() and somewhat 4 remedies the fact, that this way NUnit doesn't 3 give string representations of the objects 2 in case the test fails.

So here it is:

using NUnit.Framework;

public static class Affirm
{
    public static Affirmer That(object actual)
    {
        return new Affirmer(actual);
    }
}

[EditorBrowsable(EditorBrowsableState.Never)]
public class Affirmer
{
    readonly object _actual;

    public Affirmer(object actual)
    {
        _actual = actual;
    }

    public void IsEqualTo(object expected)
    {
        string failureMessage = string.Format("\nExpected: <{0}>\nBut was:  <{1}>", _actual, expected);
        Assert.That(_actual.Equals(expected), Is.True, failureMessage);
    }

    public void IsNotEqualTo(object expected)
    {
        string failureMessage = string.Format("\nDid not excpect: <{0}>\nBut was:         <{1}>", _actual, expected);
        Assert.That(_actual.Equals(expected), Is.False, failureMessage);
    }
}

Use 1 it like this:

Affirm.That(actualObject).IsEqualTo(expectedObject);

and

Affirm.That(actualObject).IsNotEqualTo(expectedObject);

Hope this helps.

Some frameworks allow for equality to work 11 differently before the Id is assigned (ie, the 10 Entity is unsaved) than afterwarsd, when 9 its clear that the intent is that the Entity 8 Id is the sole basis for quality. Are you 7 using some sort of framework or is Entity 6 your own class?

If it's your own class can 5 you show the gist of your Equals() logic?

Cheers, Berryl

FYI 4 Assert.AreSame is NEVER a test to validate 3 your implementation of IEquatable! See ReferenceEquals 2 in your help doc to understand that assertion 1 better.

It should work (see this related question) if the Equals 7 method was overridden correctly. Could it 6 be a problem with your Equals method (although 5 if it simply consists of int comparison 4 I would think not)? Might be worth setting 3 a break point in your Equals method and 2 then running the test to see what's going 1 on behind the scenes.

You might want to check out this question: NUnit's Assert.Equals throws exception "Assert.Equals should not be used for assertions"

tl;dr; Assert.Equals(obj1, obj2) is 2 overridden by NUnit, and throws an exception. You 1 should use Assert.AreEqual(obj1, obj2) instead.