Question: Nullable Immutable Arrays

First off, amazing project. 😃 We are using it for ExtendedXmlSerializer.

Secondly, finally ran into my first problem here after many (many!) times of “just working”.

I have the following class:

class Subject
{
    public Subject(ImmutableArray<int>? test)
    {
        Test = test;
    }

    public ImmutableArray<int>? Test { get; }
}

But when I do this:

new Subject(ImmutableArray.Create(1, 2, 3))
    .ShouldBeEquivalentTo(new Subject(ImmutableArray.Create(1, 2, 3)));

I get the following failure: Expected member Test to be {1, 2, 3}, but found {1, 2, 3}.

Looks like it has to do with being a nullable value type. If I make it non-nullable it works as expected. Any suggestions on what I could be doing wrong? Thank you in advance for any assistance!

[eNeRGy164]

Source: http://www.continuousimprover.com/2018/02/fluent-assertions-50-best-unit-test.html

[dennisdoomen]

If I change my Test property from a ImmutableArray? to a ImmutableArray it works just fine

I found the problem. Nullable properties referring to types implementing IEnumerable are not detected as such, after which FA will fall back on value semantics. And ImmutableArray implements Equals by comparing the underlying arrays by reference.