How can I verify the minimum coverage with some excluded classes and with the jacoco plugin? : <p>I need to check the minimum coverage with the new jacoco task</p>

<p><strong>jacocoTestCoverageVerification</strong></p>

<p>This task is available with in the 3.4.1 gradle release and with the jacoco plugin >= 0.6.3</p>

<p>I could run another task that generates an html report with the branch coverage but now I want to use that number to make the build fail.</p>

<p>This is my code</p>

<pre><code>buildscript {
    ext {
        ....
    }
    repositories {
        mavenCentral()
        maven {
            ....
        }
    }
    dependencies {
        .....
    }
}


apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
apply plugin: 'jacoco'

jar {
    baseName = "coverage-test"
}


dependencies {
    // my dependencies
}


eclipse {
    classpath {
         containers.remove('org.eclipse.jdt.launching.JRE_CONTAINER')
         containers 'org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8'
    }
}

wrapper {
    gradleVersion = '3.4.1'
}

jacoco {
    toolVersion = '0.7.9'
}

jacocoTestReport {
    reports {
        xml.enabled false
        csv.enabled false
    }    
    group = "Reporting"
    description = "Generate Jacoco coverage reports after running tests."
    additionalSourceDirs = files(sourceSets.main.allJava.srcDirs)

    afterEvaluate {
        classDirectories = files(classDirectories.files.collect {
            fileTree(
                dir: it,
                excludes: 
                [
                        'com/jacoco/dto/**',
                        'com/jacoco/configs/**', 
                        //and others
                ])
        })
    }
}

jacocoTestCoverageVerification {

    //I tried this and it didn't work

  //   classDirectories = files(classDirectories.files.collect {
  //   fileTree(
  //    dir: it,
        // excludes: 
        // [
        //      'com/jacoco/dto/**',
        //      'com/jacoco/configs/**', 
        //      //and others
        // ])
  //   })

    violationRules {
        rule {
            //Also tried this and it didn't work

           // excludes = ['com/jacoco/dto/**', ...]

            limit {
                counter = 'BRANCH'
                minimum = 0.8
            }
        }
    }
}
check.dependsOn jacocoTestCoverageVerification
</code></pre>

<p>With <strong>classDirectories</strong> I get the following error <em>Cannot get property 'files' on null object</em>. And with the second option (only <strong>excludes</strong>), the build run smoothly but It doesn't exclude any class.</p>
