This is a simple solution built as a starter for writing Fody addins.

The project that does the weaving.

It outputs a file named SampleFodyAddin.Fody. The '.Fody' suffix is necessary for it to be picked up by Fody.

ModuleWeaver.cs is where the target assembly is modified. Fody will pick up this type during a its processing.

In this case a new type is being injected into the target assembly that looks like this.

public class Hello
{
    public string World()
    {
        return "Hello World";
    }
}

See ModuleWeaver for more details.

Fody addins are deployed as nuget packages. NugetProject builds the package for SampleFodyAddin as part of a build. The output of this project is placed in SolutionDir/NuGetBuild.

This project uses pepita to construct the package but you could also use nuget.exe.

For more information on the nuget structure of Fody addins see DeployingAddinsAsNugets

A target assembly to process and then validate with unit tests.

This is where you would place your unit tests.

Note that it does not reference AssemblyToProcess as this could cause assembly loading issues. However we want to force AssemblyToProcess to be built prior to the Tests project. So in Tests.csproj there is a non-reference dependency to force the build order.

<ProjectReference Include="..\AssemblyToProcess\AssemblyToProcess.csproj">
  <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
</ProjectReference>

The test assembly contains three parts.

A helper class that takes the output of AssemblyToProcess and uses ModuleWeaver to process it. It also create a copy of the target assembly suffixed with '2' so a side-by-side comparison of the before and after IL can be done using a decompiler.

A helper class that runs peverfiy to validate the resultant assembly.

The actual unit tests that use WeaverHelper and Verifier. It has one test to construct and execute the injected class.

Not that there is no reference to Fody nor are any Fody files included in the solution. Interaction with Fody is done by convention at compile time.

Lego designed by Timur Zima from The Noun Project