Code snippets for the blog article at 2016/10/20/unit-tests-in-net-core-an-introduction

bash.sh

dotnet new -t xunittest

dotnet test

Project library (.NETStandard,Version=v1.6) was previously compiled. Skipping compilation.
Project test-library (.NETCoreApp,Version=v1.0) was previously compiled. Skipping compilation.
xUnit.net .NET CLI test runner (64-bit osx.10.12-x64)
  Discovering: test-library
  Discovered:  test-library
  Starting:    test-library
  Finished:    test-library
=== TEST EXECUTION SUMMARY ===
   test-library  Total: 1, Errors: 0, Failed: 0, Skipped: 0, Time: 0.288s
SUMMARY: Total: 1 targets, Passed: 1, Failed: 0.program.cs

program.cs

using static System.Console;
using Library;

namespace ConsoleApplication
{
   public class Program
   {
      public static void Main(string[] args)
      {
         // Basic use of the Thing class Get method
         var thing = new Thing();
         WriteLine($"The answer is {thing.Get(19, 23)}");
      }
   }
}

project.json

{
  "version": "1.0.0-*",
  "buildOptions": {
    "debugType": "portable"
  },
  "dependencies": {
    "System.Runtime.Serialization.Primitives": "4.1.1",
    "xunit": "2.1.0",
    "dotnet-test-xunit": "1.0.0-rc2-192208-24"
  },
  "testRunner": "xunit",
  "frameworks": {
    "netcoreapp1.0": {
      "dependencies": {
        "Microsoft.NETCore.App": {
          "type": "platform",
          "version": "1.0.0"
        }
      },
      "imports": [
        "dotnet5.4",
        "portable-net451+win8"
      ]
    }
  }
}

  "dependencies": {
    "System.Runtime.Serialization.Primitives": "4.1.1",
    "xunit": "2.1.0",
    "dotnet-test-xunit": "1.0.0-rc2-192208-24",
    "library": {
      "target": "project"
    }
  }

tests.cs

using Library;
using Xunit;

namespace TestApp
{
   public class LibraryTests
   {
      // A stupid test class which assets that 19 + 23
      // is 42, via the Thing class' Get method
      // Note: The Fact attribute tells the xunit
      // that TestThing is a single test.
      [Fact]
      public void TestThing()
      {
         Assert.Equal(42, new Thing().Get(19, 23));
      }
   }
}

thing.cs

using static Newtonsoft.Json.JsonConvert;

namespace Library
{
   public class Thing
   {
      // Takes two ints, adds them, stores them in
      // a string (using string interpolation),
      // then deserialises (via Json.Convert) back
      // to an int and returns that value
      public int Get(int left, int right) =>
         DeserializeObject<int>($"{left + right}");
   }
}