[Feature] - dynamic assertions

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Description

It would be great if asserting dynamic types could work. Especially dynamicObj.Should().BeAssignableTo<MyClass>(); would be perfect (inclusive dealing with a MyClass-object afterwards).

Expected behavior:

dynamic obj = MaybeAnAPICallWhichReturnsDynamic();

obj.Should()
    .BeAssignableTo<MyClass>()
    .Which
    ....

Actual behavior:

Test fails with “MyClass does not contain a definition for ‘Should’”

Versions

• Which version of Fluent Assertions are you using? 6.2.0
• Which .NET runtime and version are you targeting? .NET Core 3.1.

Additional Information

Any additional information, configuration or data that might be necessary to reproduce the issue.

[dennisdoomen]

Yes, you can pass in a dynamic object as the expectation. I’ve just tried that.

[kelps]

I didn’t intend to add the extension to a dynamic. The main object isn’t dynamic in my example. I intended to pass a dynamic as parameter to BeEquivalentTo (inside my custom assertion), but the main object is a real reference type, that would be compared to a dynamic, instead of an anonymous. That should be possible…