wshaddix/dotnet-skills/dotnet-add-testing

MyApp/
├── src/
│   ├── MyApp.Core/
│   ├── MyApp.Api/
│   └── MyApp.Infrastructure/
└── tests/
    ├── MyApp.Core.UnitTests/
    ├── MyApp.Api.UnitTests/
    ├── MyApp.Api.IntegrationTests/
    └── Directory.Build.props          # Test-specific build settings

# Create xUnit test project
dotnet new xunit -n MyApp.Core.UnitTests -o tests/MyApp.Core.UnitTests
 
# Add to solution
dotnet sln add tests/MyApp.Core.UnitTests/MyApp.Core.UnitTests.csproj
 
# Add reference to the project under test
dotnet add tests/MyApp.Core.UnitTests/MyApp.Core.UnitTests.csproj \
  reference src/MyApp.Core/MyApp.Core.csproj

<!-- tests/MyApp.Core.UnitTests/MyApp.Core.UnitTests.csproj -->
<Project Sdk="Microsoft.NET.Sdk">
  <ItemGroup>
    <PackageReference Include="Microsoft.NET.Test.Sdk" />
    <PackageReference Include="xunit.v3" />
    <PackageReference Include="xunit.runner.visualstudio" />
    <PackageReference Include="coverlet.collector" />
  </ItemGroup>
  <ItemGroup>
    <ProjectReference Include="..\..\src\MyApp.Core\MyApp.Core.csproj" />
  </ItemGroup>
</Project>

<!-- tests/Directory.Build.props -->
<Project>
  <Import Project="$([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../'))" />
  <PropertyGroup>
    <IsPackable>false</IsPackable>
    <IsTestProject>true</IsTestProject>
    <!-- Use Microsoft.Testing.Platform v2 runner (requires Microsoft.NET.Test.Sdk 17.13+/18.x) -->
    <UseMicrosoftTestingPlatformRunner>true</UseMicrosoftTestingPlatformRunner>
    <!-- Relax strictness for test projects -->
    <TreatWarningsAsErrors>false</TreatWarningsAsErrors>
  </PropertyGroup>
</Project>

<!-- In Directory.Packages.props -->
<ItemGroup>
  <!-- Test packages -->
  <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.0.1" />
  <PackageVersion Include="xunit.v3" Version="3.2.2" />
  <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.5" />
  <PackageVersion Include="coverlet.collector" Version="8.0.0" />
</ItemGroup>

<PackageVersion Include="NSubstitute" Version="5.3.0" />

<PackageVersion Include="FluentAssertions" Version="8.0.1" />

# Collect coverage (Cobertura format by default)
dotnet test --collect:"XPlat Code Coverage"
 
# Results appear in TestResults/*/coverage.cobertura.xml

<!-- In test csproj or tests/Directory.Build.props -->
<PackageReference Include="coverlet.msbuild" />

# Enforce minimum coverage threshold
dotnet test /p:CollectCoverage=true \
  /p:CoverageOutputFormat=cobertura \
  /p:Threshold=80 \
  /p:ThresholdType=line

# Install globally
dotnet tool install -g dotnet-reportgenerator-globaltool
 
# Generate HTML report
reportgenerator \
  -reports:"tests/**/coverage.cobertura.xml" \
  -targetdir:coverage-report \
  -reporttypes:Html

[tests/**.cs]
# Allow underscores in test method names (Given_When_Then or Should_Behavior)
dotnet_diagnostic.CA1707.severity = none
 
# Test parameters are validated by the framework
dotnet_diagnostic.CA1062.severity = none
 
# ConfigureAwait not relevant in test context
dotnet_diagnostic.CA2007.severity = none
 
# Tests often have intentionally unused variables for assertions
dotnet_diagnostic.IDE0059.severity = suggestion

namespace MyApp.Core.UnitTests;
 
public class SampleServiceTests
{
    [Fact]
    public void Method_Condition_ExpectedResult()
    {
        // Arrange
        var sut = new SampleService();
 
        // Act
        var result = sut.DoWork();
 
        // Assert
        Assert.NotNull(result);
    }
 
    [Theory]
    [InlineData(1, 2, 3)]
    [InlineData(0, 0, 0)]
    [InlineData(-1, 1, 0)]
    public void Add_TwoNumbers_ReturnsSum(int a, int b, int expected)
    {
        var result = Calculator.Add(a, b);
        Assert.Equal(expected, result);
    }
}

# Restore (regenerate lock files if using CPM)
dotnet restore
 
# Build (verifies project references and analyzer config)
dotnet build --no-restore
 
# Run tests
dotnet test --no-build
 
# Run with coverage
dotnet test --collect:"XPlat Code Coverage"

dotnet new xunit -n MyApp.Api.IntegrationTests -o tests/MyApp.Api.IntegrationTests
dotnet sln add tests/MyApp.Api.IntegrationTests/MyApp.Api.IntegrationTests.csproj
dotnet add tests/MyApp.Api.IntegrationTests/MyApp.Api.IntegrationTests.csproj \
  reference src/MyApp.Api/MyApp.Api.csproj

<!-- Version must match the project's target framework major version -->
<PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.0" />
<PackageVersion Include="Testcontainers" Version="4.3.0" />