Coverlet with MTP 2 doesn't show test coverage statistic in console

[vadim-96]

Describe the bug
The coverlet 10 with MTP 2 (xunit.v3.mtp-v2 v3.2.2) doesn't show any information about test coverage in console after dotnet test.
But the coverlet.msbuild 10 without mtp (xunit.v3 v3.2.2) shows the coverage information in console.

To Reproduce
Run commands on any test project:
dotnet test --project ./tests.csproj --no-restore --coverlet --coverlet-exclude-assemblies-without-sources MissingAll --coverlet-output-format teamcity
OR
dotnet test --project ./tests.csproj /p:CollectCoverage=true /p:CoverletOutputFormat=teamcity /p:ExcludeAssembliesWithoutSources=MissingAll

Expected behavior
Expect coverage results in console.

Actual behavior
No reports from the coverlet in console.

Configuration:
csproj:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net10.0</TargetFramework>
    <OutputType>Exe</OutputType>
    <LangVersion>latest</LangVersion>
    <UseMicrosoftTestingPlatformRunner>true</UseMicrosoftTestingPlatformRunner>
    <Nullable>enable</Nullable>
    <IsPackable>false</IsPackable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="coverlet.MTP" Version="10.0.0" />
    <PackageReference Include="Microsoft.Testing.Platform" Version="2.2.1" />
    <PackageReference Include="Moq" Version="4.20.72" />
    <PackageReference Include="xunit.v3.mtp-v2" Version="3.2.2" />
  </ItemGroup>
  
</Project>

global.json:

{
    "test": {
        "runner": "Microsoft.Testing.Platform"
    }
}

[Bertk]

Thank you for raising this.

What you’re observing is expected behavior. The MTP integration is aligned with coverlet.collector rather than coverlet.msbuild. Unlike the MSBuild integration, the collector-based approach does not print coverage results to the console by default.

So in this context, coverlet.MTP is not intended to be a direct successor to the MSBuild package, and therefore behaves differently.

That said, your point is valid—having immediate feedback in the console can be helpful. At the moment, the recommended approach is to generate coverage reports and use a reporting tool (for example, ReportGenerator or similar) to surface the results in your pipeline.

I agree this could be considered a potential improvement, but there are also IDE tools that provide a more user-friendly experience.

similar issue for coverlet.collector #681

[vadim-96]

TeamCity parses the code coverage statistic as service messages from the console.
If you use --coverlet-output-format teamcity, the result will be saved as a file, which is pointless to use teamcity parameter.

[Bertk]

The issue will be resolved with next coverlet release.