Failed to run test because null with nested test classes.

Environment data

dotnet --info output: 1.0.0-preview2-003133 VS Code version: 1.9.0-insider C# Extension version: 1.6.2

Steps to reproduce

For us the problem was nested classes. OmniSharp cannot handle this, when we click run test.

    public class SomeClass
    {
        public class SomeMethod
        {
            // Trying to run this test causes
            // "Failed to run test because null"
            [Fact]
            public void SomeTest()
            {
    
            }
        }
    }

Expected behavior

The test runs and the output says “Test Passed”.

Actual behavior

Failed to run test because null

[DustinCampbell]

OK. I see why the problem is specific to tests in nested classes. The offending line of code is here: https://github.com/OmniSharp/omnisharp-roslyn/blob/dev/src/OmniSharp.DotNetTest/Helpers/TestFeaturesDiscover.cs#L41.

Essentially, the code expects Roslyn’s ISymbol.ToDisplayName() to return a name that can be used with ‘dotnet test’. However, that method returns strings for display. Between a class and a nested class, it uses a ‘.’ separator. However, ‘dotnet test’ expects a metadata name when the class and nested class are separated by a ‘+’. I had to write code that produced a metadata name once before – for Code Model in VS (https://github.com/dotnet/roslyn/blob/master/src/VisualStudio/Core/Impl/CodeModel/MetadataNameHelpers.cs). Looks like I might have to do that again. 😄

[gregg-miskelly]

Okay, I will reopen for now then.