How to make Jenkins stage fail and turn red when coverage is too low (using C# and dotnet test)?

Question

I am using C#, coverlet.msbuild and the Jenkins Cobertura adapter. I have roughly this in my Jenkinsfile:

stage ('Run unit tests') {
    steps {
        powershell "dotnet test -c:Release /p:CollectCoverage=true /p:CoverletOutputFormat=cobertura --no-build --no-restore --logger trx"
    }
    post {
        always {
            step([$class: 'MSTestPublisher'])
            publishCoverage failUnhealthy: true, 
                globalThresholds: [[thresholdTarget: 'Package', unhealthyThreshold: 50.0]],
                adapters: [coberturaAdapter(
                    mergeToOneReport: true, 
                    path: '**/*.cobertura.xml')]
        }
    }
}

This makes my Jenkins build fail if coverage is below 50% at package level. So far so good.

But when a build fails due to this, it is user-hostile and hard to see why. The 'Run unit tests' stage is green in Blue Ocean.

Can I make this stage turn red when it fails the build, so it is easier to see what the error is?

Answer 1

Inspired by the answer from Sers and some other Jenkinsfile code I read through, I arrived at this solution, which does what I want:

stage ('Run unit tests') {
    steps {
        powershell "dotnet test -c:Release /p:CollectCoverage=true /p:CoverletOutputFormat=cobertura --no-build --no-restore --logger trx"
    }
    post {
        always {
            step([$class: 'MSTestPublisher'])
            publishCoverage failUnhealthy: true, 
                globalThresholds: [[thresholdTarget: 'Package', unhealthyThreshold: 50.0]],
                adapters: [coberturaAdapter(
                    mergeToOneReport: true, 
                    path: '**/*.cobertura.xml')]
            script {
                if (currentBuild.result == 'FAILURE') {
                    error("Test coverage is too low.")
                }
            }
        }
    }
}