dotnet-nunit

NUnit Testing

Trigger On

• writing or reviewing NUnit tests
• using [Test], [TestCase], [TestFixture], [SetUp], [TearDown] attributes
• configuring NUnit3TestAdapter or NUnit.Analyzers
• migrating between NUnit versions
• integrating NUnit with CI pipelines

Documentation

• NUnit Documentation
• NUnit GitHub
• NUnit3TestAdapter
• NUnit Analyzers

References

• patterns.md — Test patterns, assertions, parameterized tests, lifecycle
• anti-patterns.md — Common NUnit mistakes and fixes

Package Selection

Package	Purpose
NUnit	Core testing framework
NUnit3TestAdapter	VSTest adapter for dotnet test
NUnit.Analyzers	Roslyn analyzers for NUnit best practices
Microsoft.NET.Test.Sdk	Required for test discovery

Project Setup

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
    <IsPackable>false</IsPackable>
    <IsTestProject>true</IsTestProject>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.*" />
    <PackageReference Include="NUnit" Version="4.*" />
    <PackageReference Include="NUnit3TestAdapter" Version="4.*" />
    <PackageReference Include="NUnit.Analyzers" Version="4.*">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
    </PackageReference>
  </ItemGroup>
</Project>

Test Patterns

Basic Test Structure

[TestFixture]
public class CalculatorTests
{
    private Calculator _calculator;

    [SetUp]
    public void SetUp()
    {
        _calculator = new Calculator();
    }

    [TearDown]
    public void TearDown()
    {
        _calculator?.Dispose();
    }

    [Test]
    public void Add_TwoPositiveNumbers_ReturnsSum()
    {
        var result = _calculator.Add(2, 3);

        Assert.That(result, Is.EqualTo(5));
    }

    [Test]
    public void Divide_ByZero_ThrowsException()
    {
        Assert.Throws<DivideByZeroException>(() => _calculator.Divide(10, 0));
    }
}