Incorrect NS3004 for derived types

[samcragg]

First of all, the analyzer is really useful - thanks for creating the project!

I think I'm incorrectly getting the Could not set value of type … to argument ... because the types are incompatible error when trying to assign a Dictionary to a IReadOnlyDictionary argument and was able to reproduce it with this code:

using NSubstitute;
using Xunit;

public class ExampleTest
{
    public interface IExampleInterface
    {
        bool Method(out object value);
    }

    [Fact]
    public void DictionaryTest()
    {
        IExampleInterface substitute = Substitute.For<IExampleInterface>();
        substitute.Method(out Arg.Any<object>())
            .Returns(ci =>
            {
                ci[0] = "string";
                return true;
            });

        bool result = substitute.Method(out object value);

        Assert.True(result);
        Assert.Equal("string", value);
    }
}

The line with ci[0] = "string"; triggers the analyser error, however, the test succeeds in passing (i.e. NSubstitute does correctly set the parameter).

I think the problem is we're checking if the type is equal instead of if the assignment will work in AbstractCallInfoAnalyzer.cs - maybe Equals should be replaced with a call to CanCast?

[tpodolak]

@samcragg thanks for reporting. I will take a look at this once I am back from holidays. When it comes to Equals and CanCast usages I remember than Nsubstitute does different type checks depending on the context. Can you tell me which version of Nsubstitute you use?

[samcragg]

Cool, thanks for that. I've tried it in both 4.0.0-rc1 and 3.1.0 (the latest stable) against version 1.0.3 of the analyser - both times the test passes but the analyser reports an error.

[tpodolak]

Released in 1.0.4