Debugging xUnit tests in .NET Core and Visual Studio Code

Question

I'm on a Mac, running .NET Core 1.0 and Visual Studio Code.

I have a console project and a test project. I have setup launch.json so that I can debug the console project.

How do I set up a launch configuration that launches my unit tests and attaches the debugger?

Answer 1

If you install the latest software and library, it is super easy to debug:

As you can see from the screenshot, just click "debug test" and debug it!

Answer 2

See Tyler Long's answer . The steps below are not required in the newest versions of Visual Studio Code :)

---

I made a repository to demonstrate.

First off, the only way I could get the debugger to hit the test was to add a file, Program.cs, take control of the entry point from xUnit, and manually add code to test. It's not ideal, but I imagine you aren't going to be doing this very often, and it's easy to flip it back to normal.

Program.cs:

using System;
namespace XUnitDebugging
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var test = new TestClass();
            test.PassingTest();
            Console.WriteLine("Enter text...");
            Console.ReadLine();

        }
    }
}

Next, in project.json add the following:

  "buildOptions": {
    "emitEntryPoint": true,
    "debugType": "portable"
  },

project.json:

{
  "version": "1.0.0-*",
  "testRunner": "xunit",
  "buildOptions": {
    "emitEntryPoint": true,
    "debugType": "portable"
  },
  "dependencies": {
    "Microsoft.NETCore.App": {
      "type": "platform",
      "version": "1.0.0"
    },
    "xunit": "2.2.0-beta2-build3300",
    "dotnet-test-xunit": "2.2.0-preview2-build1029"
  },
  "frameworks": {
    "netcoreapp1.0": {
      "dependencies": {
        "Microsoft.NETCore.App": {
          "type": "platform",
          "version": "1.0.0"
        }
      }
    }
  }
}

This will allow you to debug an xUnit unit test project.

Answer 3

I was able to run the debugger on an entire xUnit project with the following complicated launch config. I inspected the calls the "debug test" link (in @Tyler Long response above) was making through the C# (Omnisharp) VS Code extension to figure this out. Things to note: 1) you must provide the absolute path to the dotnet program 2) you must provide the absolute path (ie you cannot use ~/ or $HOME/ ) to .nuget/packages folders 3) in the example below, the name of my test project namespace is Tests . Once you have this launch config in place, you can place breakpoints(s), launch the debugger using this config and it should hit all the breakpoints.

{
  "name": "Debug xunit tests",
  "type": "coreclr",
  "request": "launch",
  "preLaunchTask": "build",
  "program": "/usr/local/share/dotnet/dotnet",
  "args": [
    "exec",
    "--runtimeconfig",
    "${workspaceRoot}/AppNameHere/bin/Debug/netcoreapp1.0/AppNameHere.runtimeconfig.json",
    "--depsfile",
    "${workspaceRoot}/AppNameHere/bin/Debug/netcoreapp1.0/AppNameHere.deps.json",
    "--additionalprobingpath",
    "/Users/jdoe/.nuget/packages",
    "/Users/jdoe/.nuget/packages/dotnet-test-xunit/1.0.0-rc2-build10015/lib/netcoreapp1.0/dotnet-test-xunit.dll",
    "${workspaceRoot}/AppNameHere/bin/Debug/netcoreapp1.0/AppNameHere.dll",
    "-namespace",
    "Tests"
  ],
  "cwd": "${workspaceRoot}",
  "stopAtEntry": false
}

Answer 4

Tyler's answer of clicking the debug test code lens icons is the easiest way of debugging a single test.

A way of testing all unit tests would be to add while(!Debugger.IsAttached) Thread.Sleep(500); inside the tests. This will make the tests wait until you attach a debugger.

using System;
using System.Diagnostics;
using System.Threading;
using NUnit.Framework;

namespace SomeNamespace
{
    [TestFixture]
    public class SomeClassTests
    {
        [Test]
        public void ShouldDoTest()
        {
            while(!Debugger.IsAttached) Thread.Sleep(500);
            Assert.That(true, Is.True);
        }

        [Test]
        public void ShouldDoTest2()
        {
            while(!Debugger.IsAttached) Thread.Sleep(500);
            Assert.That(true, Is.True);
        }
    }
}

This then allows you to attach the Visual Studio Code debugger to the running testhost.dll. Simple select .NET Core Attach and then the dotnet testhost.dll .