PostSharp.Testing.AspectTesting 2027.0.7-preview

A test framework for PostSharp aspects, based on xunit.v3. Each source file of the test project is a test: the framework compiles it, weaves it with PostSharp, verifies the woven assembly, and runs its Main method. A test passes when the weaving reports the expected messages and the program returns 0.

Create an xunit.v3 test project, reference this package, the xunit.v3 package and the packages of your aspects, and add test files to it. The files are not compiled into the test project: the framework compiles each one separately.

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net10.0</TargetFramework>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="xunit.v3" Version="4.0.1" />
    <PackageReference Include="PostSharp.Testing.AspectTesting" Version="..." />
    <PackageReference Include="MyAspects" Version="..." />
  </ItemGroup>
</Project>

A test file configures its test with directives in comments. For example, // @ExpectedMessage(MY001) expects the message MY001 that your aspect reports when it is misused, // @SkipRuntime weaves and verifies the test without running it, and // @TestRun(Name) runs the test once more under that name. Run the tests as any xunit.v3 test project, with dotnet test or the test executable.

To compare the output of each program and the messages of its build with files next to the test, set PostSharpTestOutputFileSuffix (such as .txt for Foo.txt) and PostSharpTestMessagesFileSuffix (such as .build.txt) in the test project. A missing file stands for an empty result. When a result differs, the test fails and the actual result is written next to the expected file (Foo.actual.txt). Run dotnet build -t:AcceptTestOutput on the test project to copy the actual results over the expected files, or run the tests with dotnet test -p:PostSharpTestAcceptResults=True to overwrite the expected files instead of comparing them.

To see what PostSharp wove, add // @CompareTransformedCode to a test file. The framework decompiles the woven assembly to C# and compares it with Foo.t.cs next to the test, with the same rules and the same accept commands. Only the declarations marked with a // <target> comment are shown, or every type of the file when none is marked.

To run the same tests twice in a report that merges tests of the same name, set PostSharpTestDisplayNameSuffix in one of the runs, such as dotnet test -p:PostSharpTestDisplayNameSuffix=Release: the display name of each test then ends with [Release].