Coverlet: Why Coverlet use custom attribute ExcludeFromCoverage instead of ExcludeFromCodeCoverage

[abakumov-v]

Hi guys!

Why Coverlet use the custom attribute ExcludeFromCoverage from its own namespace instead of using already exists in .NET Core attribute ExcludeFromCodeCoverage from namespace System.Diagnostics.CodeAnalysis?

To Coverlet ignore any class, I need to install the nuget package coverlet.msbuild in all projects with tests, right?

[tonerdo]

@Valeriy1991 no, you can create a ExcludeFromCoverage attribute and use that. Coverlet uses the name and not the full type so anyone will work.

[StillLearnin]

Is there any reason to not support ExcludeFromCodeCoverage as well? That would make it easier to transition to Coverlet from other products.

[abakumov-v]

Hello! I'm still work on adding support on both attributes: ExcludeFromCoverage from Coverlet and ExcludeFromCodeCoverage from System.Diagnostics.CodeAnalysis in my fork.

[StillLearnin]

In case you're wondering where to make the change it's right here... (in Coverlet.Core.Instrumentation.Instrumentation)

        private void InstrumentModule()
        {
            using (var stream = new FileStream(_module, FileMode.Open, FileAccess.ReadWrite))
            {
                var parameters = new ReaderParameters { ReadSymbols = true };
                ModuleDefinition module = ModuleDefinition.ReadModule(stream, parameters);

                foreach (var type in module.GetTypes())
                {
                    if (type.CustomAttributes.Any(a => a.AttributeType.Name == "ExcludeFromCoverageAttribute" || a.AttributeType.Name == "ExcludeFromCoverage"))
                        continue;

                    foreach (var method in type.Methods)
                    {
                        if (!method.CustomAttributes.Any(a => a.AttributeType.Name == "ExcludeFromCoverageAttribute" || a.AttributeType.Name == "ExcludeFromCoverage"))
                            InstrumentMethod(method);
                    }
                }

                module.Write(stream);
            }
        }

[abakumov-v]

@StillLearnin thanks, I'm in the know. But first I want to add unit tests to check the current functionality (use ExcludeFromCoverage attribute)

[tonerdo]

Now available in https://www.nuget.org/packages/coverlet.msbuild/2.0.1

[svenskmand]

Hi :)

I cannot get this to work. If I include the ExcludeByAttribute property in my *.Tests.csproj file and add a property GeneratedCode to my generated code project then Coverlet still computes coverage for the generated code. Similarly if I add the property ExcludeFromCoverage to my generated code project coverage is again still computed for the project.

Here is my *.Tests.csproj file:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>netcoreapp3.1</TargetFramework>
    <IsPackable>false</IsPackable>
    <CollectCoverage>true</CollectCoverage>
    <CoverletOutputFormat>lcov</CoverletOutputFormat>
    <CoverletOutput>./Datahub/lcov.info</CoverletOutput>
    <ExcludeByAttribute>GeneratedCode</ExcludeByAttribute>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="coverlet.msbuild" Version="2.8.0">
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      <PrivateAssets>all</PrivateAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />
    <PackageReference Include="xunit" Version="2.4.0" />
    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.0" />
    <PackageReference Include="coverlet.collector" Version="1.0.1" />
    <PackageReference Include="FluentAssertions" Version="5.10.0" />
  </ItemGroup>

  <ItemGroup>
    ... project references ...
  </ItemGroup>
</Project>

and here is my ProtoBuf.csproj file for the generated code:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>netcoreapp3.1</TargetFramework>
    <GeneratedCode>GeneratedCode</GeneratedCode>
    <ExcludeFromCoverage/>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Google.Protobuf" Version="3.11.2" />
    <PackageReference Include="Grpc" Version="2.26.0" />
    <PackageReference Include="Grpc.Tools" Version="2.26.0" PrivateAssets="All">
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      <PrivateAssets>all</PrivateAssets>
    </PackageReference>
  </ItemGroup>

  <ItemGroup>
    <Protobuf Include="**/*.proto" />
  </ItemGroup>
</Project>

Am I missing something or what is wrong?

Thanks :)

[MarcoRossignoli]

@svenskmand please open new issue, we'll discuss there.

[svenskmand]

@MarcoRossignoli Ok, thanks :) I have opened a new issue here.