Kotlin Test Coverage

Question

Does anyone know if a good test coverage tool (preferably Gradle plugin) exists for Kotlin? I've looked into JaCoCo a bit, but it doesn't seem to reliably support Kotlin.

Answer 1

As requested, here is an example build.gradle that uses Kotlin, and incorporates both Jacoco and Sonarqube integration, produces a jar and sources, and ties in Detekt for static analysis.

I had to manually add a couple things as my work build has jacoco applied by an in-house plugin.

plugins {
    id 'org.jetbrains.kotlin.jvm' version '1.2.10'
    id 'org.jetbrains.kotlin.plugin.spring' version '1.2.10'
    id 'org.springframework.boot' version '1.5.9.RELEASE'
    id 'io.spring.dependency-management' version '1.0.4.RELEASE'
    id 'io.gitlab.arturbosch.detekt' version '1.0.0.RC6'
    id "org.sonarqube" version "2.6.2".  
}

apply plugin: 'jacoco'

ext {
    springBootVersion = '1.5.9.RELEASE'
    springCloudVersion = 'Dalston.SR4'
    kotlinVersion = '1.2.10'
    detektVersion = '1.0.0.RC6'.  
}

//======================= Project Info =============================================
group = 'group'
version = '0.14'

dependencyManagement {
    imports {
        mavenBom("org.springframework.boot:spring-boot-starter-        parent:$springBootVersion") 
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:$springCloudVersion"
    }
}

repositories {
    jcenter()
}

//======================= Dependencies =============================================
dependencies {
    // Version MUST be explicitly set here or else dependent projects will not be able to build as Gradle will not know
    // what version to use
    compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlinVersion"

    compile 'org.springframework.boot:spring-boot-starter-web'
    compile('org.springframework.ws:spring-ws-support') {
        exclude(module: 'javax.mail')
    }
    compile 'org.springframework.boot:spring-boot-starter-actuator'

    // Spring security
    compile 'org.springframework.security:spring-security-web'
    compile 'org.springframework.security:spring-security-config'
    compile 'javax.servlet:javax.servlet-api'
    compile 'com.fasterxml.jackson.dataformat:jackson-dataformat-yaml'
    compile('org.apache.httpcomponents:httpclient')
    compile 'com.nimbusds:nimbus-jose-jwt:4.23'
}

//======================= Tasks =============================================
defaultTasks 'build'

tasks.bootRepackage.enabled = false

tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).all {
    kotlinOptions {
        jvmTarget = 1.8
        freeCompilerArgs = ["-Xjsr305=strict"]
    }
}

compileJava.options.encoding = 'UTF-8'

test.testLogging.exceptionFormat = 'full'

// ********************************

ext.coverageExclusions = [
    // Configuration
    'com.bns.pm.config.*',
    // data classes
    'com.bns.pm.domain.*',
    // Account Service domain objects
    'com.bns.pm.account.domain.*',
    // Other items
    'com.bns.pm.exceptions.DataPowerFaultException.Companion',
    'com.bns.pm.controllers.ServiceExceptionHandler*',
    'com.bns.pm.service.callback.DPWebServiceMessageCallback',
    'com.bns.pm.service.HealthCheckService',
    'com.bns.pm.util.SystemPropertiesUtilKt',
]

check.dependsOn jacocoTestCoverageVerification
jacocoTestCoverageVerification {
    violationRules {
        rule {
            element = 'CLASS'
            // White list
            excludes = coverageExclusions
            limit {
                minimum = 0.70
            }
        }
    }
}

jacocoTestReport {
    description 'Generates Code coverage report. Fails build if it does not meet minimum coverage.'

    reports {
        xml.enabled = true    //XML required by coveralls and for the     below coverage checks
        html.enabled = true
        csv.enabled = false
    }

    def reportExclusions = coverageExclusions.collect {
        it.replaceAll('\\.', '/') + (it.endsWith('*') ? '' : '*')
    }
    afterEvaluate {
        classDirectories = files(classDirectories.files.collect {
            fileTree(dir: it, excludes: reportExclusions)
        })
    }
}

test.finalizedBy jacocoTestReport

afterEvaluate {
    sonarqube {
        properties {
            property 'sonar.jacoco.reportPath', "${buildDir}/jacoco/test.exec"
            property "detekt.sonar.kotlin.config.path", "detekt.yml"
            property 'sonar.java.binaries', "$projectDir/build/classes/kotlin"
            property 'sonar.coverage.exclusions', coverageExclusions.collect {
                '**/' + it.replaceAll('\\.', '/') + (it.endsWith('*') ? '' : '*')
            }
        }
    }
}

// Ensure source code is published to Artifactory
// Have to redefine publishing with new name as Accelerator Plugin already defined mavenJava
task sourceJar(type: Jar) {
    from sourceSets.main.allSource
    classifier 'sources'
}

publishing {
    publications {
        mavenJava2(MavenPublication) {
            from components.java
            artifact(sourceJar) {
                classifier = 'sources'
            }
        }
    }
}

artifactory {
    contextUrl = "${artifactory_contextUrl}"
    publish {
        repository {
            repoKey = "${artifactory_projectRepoKey}"
            username = "${artifactory_user}"
            password = "${artifactory_password}"
            maven = true
        }
        defaults {
            publications('mavenJava2')
        }
    }
}

artifactoryPublish {
    dependsOn jar
}

detekt {
    version = detektVersion
    profile("main") {
        input = "$projectDir/src"
        config = "$projectDir/detekt.yml"
        filters = ".*/resources/.*,.*/tmp/.*"
        output = "$project.buildDir/reports/detekt"
    }
}
check.dependsOn detektCheck