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nunit-build-infra

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Use when editing `.csproj`, `.nuspec`, `Directory.Build.props`, `Directory.Build.targets`, `Directory.Packages.props`, the Cake build (`build.cake`, `build.ps1`, `build.sh`), or GitHub Actions workflows. Covers central package management, MinVer-driven versioning, the props-vs-targets split, and nuspec/csproj consistency.

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NUnit build infrastructure

The build is opinionated. Several patterns that look like ordinary csproj/nuspec editing in other repos are wrong here, and a few that look strange are load-bearing. When editing any build file, follow these conventions.

Adding a package dependency

Two files always change, in lockstep:

  1. Add the version to src/NUnitFramework/Directory.Packages.props:
   <PackageVersion Include="SomePackage" Version="1.2.3" />
  1. Add a version-less reference in the consuming .csproj:
   <PackageReference Include="SomePackage" />

Never put Version="..." on a <PackageReference>. If you see one in a diff (often left by an IDE after a package update), delete the attribute.

Adding a build-only or analyzer-only package

Mark with PrivateAssets="all" so it doesn't propagate to consumers, and place under the analyzers/build-tooling ItemGroup in Directory.Build.props rather than per-project:

<PackageReference Include="StyleCop.Analyzers" PrivateAssets="all" />

In the corresponding nuspec entry, mark such packages as developmentDependency="true" so consumers of the NUnit nuget don't pull them transitively.

Versioning — don't touch it

Versioning is handled at build time by MinVer, which derives the version from git tags. Specifically:

  • Never set <AssemblyVersion>, <FileVersion>, <Version>, or <InformationalVersion> in a .csproj.
  • Never hand-write [assembly: AssemblyVersion(...)] or related attributes — <GenerateAssemblyInfo>true</GenerateAssemblyInfo> produces them.
  • The deliberate convention is that AssemblyVersion stays at Major.0.0.0 (so binding redirects don't churn on every release) while AssemblyFileVersion drifts. Don't "fix" this.

If you need to influence the version (e.g. for a release branch), do it via MinVer's environment variables in CI, not by editing project files.

Directory.Build.props vs Directory.Build.targets

The split is enforced by convention, not by MSBuild:

  • Directory.Build.props: properties (<PropertyGroup>), package references (<ItemGroup> with PackageReference), feature constants, build settings. Anything evaluated at project-load time.
  • Directory.Build.targets: <Target> definitions — anything that runs as part of the build pipeline (custom build steps, post-compile work).

Don't put a <Target> in .props or a property in .targets. Reviewers will ask you to move it.

nuspec and .csproj must agree

Each shipped NuGet has a .nuspec that lists its dependencies. Those must match the <PackageReference>s of the corresponding .csproj for each target framework.

This is asserted at test time by NuspecDependenciesTests.cs — drift fails the test suite during dotnet test. When you add a runtime dependency to a project that ships, update the nuspec in the same change. If the test reports drift, the nuspec is the file to update (not the test).

Build-only or analyzer-only packages should not appear in the nuspec, or should appear with developmentDependency="true" if they must.

Directory.Build.targets and target authoring

When adding a target:

  • Give it a clear, capitalised name that says what it does (SetAssemblyVersion, CopyContractFiles).
  • Specify when it runs explicitly (BeforeTargets="Build" / AfterTargets="..."); don't rely on placement order.
  • Targets that emit output for diagnostic purposes should respect MSBuild's terminal logger — <Message Importance="High"> is necessary to be seen with the new logger.

CI workflows (.github/workflows)

  • Don't add a new TFM build matrix entry as part of an unrelated PR — adding a TFM has consequences for package payload and is reviewed separately.
  • When adding a new dotnet step, install via actions/setup-dotnet@v4 with an explicit dotnet-version. Don't depend on the runner's preinstalled SDK.
  • Caches keyed on Directory.Packages.props and lock files — if you add a new file that influences restore, include it in the cache key.

Common cleanup tasks while editing csproj

  • IDE package-update tooling sometimes adds Version="..." to a <PackageReference> it just bumped. Delete the attribute and update Directory.Packages.props instead.
  • IDE tooling sometimes inserts <TargetFramework> for a project that defines <TargetFrameworks> (plural) centrally. Remove the singular form unless the project genuinely targets one TFM only.
  • Stale <None> / <Compile> items left behind after a file rename or move — clean these up; SDK-style projects use globs and don't need explicit entries for normal .cs files.