JaCoCo returning 0% Coverage with Kotlin and Android 3.0

Question

I am trying to check my code coverage for a test case that I wrote in Kotlin. When I execute ./gradlew createDebugCoverageReport --info, my coverage.ec file is empty and my reports indicate that I have 0% coverage. Please note, the test cases are 100% successful. Can anyone think of any reasons my coverage.ec file keeps returning 0 bytes?

I have searched everywhere with no luck.

apply plugin: 'com.android.library'

apply plugin: 'kotlin-android'

apply plugin: 'kotlin-android-extensions'

apply plugin: 'jacoco'


android {
    compileSdkVersion 25
    buildToolsVersion "25.0.3"
    defaultConfig {
        minSdkVersion 16
        targetSdkVersion 25
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        debug {
            testCoverageEnabled = true
        }
        release {
            minifyEnabled false
            testCoverageEnabled = true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }


    testOptions {
        unitTests.all {
            jacoco {
                includeNoLocationClasses = true
            }
        }
    }

}

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    androidTestImplementation('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
    implementation 'com.android.support:appcompat-v7:25.4.0'
    testImplementation 'junit:junit:4.12'
    implementation files('pathtosomejarfile')

}



jacoco {
    toolVersion = "0.7.6.201602180812"
    reportsDir = file("$buildDir/customJacocoReportDir")

}



task jacocoTestReport(type: JacocoReport, dependsOn: ['testDebugUnitTest', 'createDebugCoverageReport']) {

    reports {
        xml.enabled = true
        html.enabled = true
    }

    def fileFilter = ['**/R.class', '**/R$*.class', '**/BuildConfig.*', '**/Manifest*.*', '**/*Test*.*', 'android/**/*.*']
    def debugTree = fileTree(dir: "${buildDir}/intermediates/classes/debug", excludes: fileFilter)
    def mainSrc = "${project.projectDir}/src/androidTest/java"

    sourceDirectories = files([mainSrc])
    classDirectories = files([debugTree])
    executionData = fileTree(dir: "$buildDir", includes: [
            "jacoco/testDebugUnitTest.exec",
            "outputs/code-coverage/connected/*coverage.ec"
    ])
}

https://stackoverflow.com/questions/45350561/android-studio-3-kotlin-code-coverage — Entreco, Aug 16 '17 at 21:32
Not just Jacoco, even the default Coverage from Intellij IDEA is also 0. Everything is 0 when it is Kotlin. https://stackoverflow.com/questions/45819700/android-studio-3-0-gradle-3-0-0-beta2-breaks-kotlin-unit-test-coverage — Elye, Aug 28 '17 at 03:04

farmerbb · Accepted Answer · 2020-07-08T20:49:07.853

29

You can get line-by-line coverage for both Java and Kotlin code by defining the two different directories for generated .class files:

def debugTree = fileTree(dir: "${buildDir}/intermediates/classes/debug", excludes: fileFilter)
def kotlinDebugTree = fileTree(dir: "${buildDir}/tmp/kotlin-classes/debug", excludes: fileFilter)

Then, simply include both fileTrees in your classDirectories:

classDirectories.from = files([debugTree], [kotlinDebugTree])

edited Jul 08 '20 at 20:49

answered Sep 06 '17 at 19:36

farmerbb

1,150
8
7

This is as per reported in stackoverflow.com/a/45354933/3286489. But if observe carefully, it is reporting the coverage of the test code, not the app code. :( – Elye Dec 12 '17 at 02:51
4

Proposed solution should work. I wasn't aware of this post, and fixed it in a similar way. Wrote a blog post about that: http://vgaidarji.me/blog/2017/12/20/how-to-configure-jacoco-for-kotlin-and-java-project/ – Veaceslav Gaidarji Dec 21 '17 at 10:42
Thanks @VeaceslavGaidarji! – Clinkz Apr 13 '18 at 04:44
classDirectories is deprecated. so what should be the answer – charitha amarasinghe Jun 12 '20 at 04:45
1

@charithaamarasinghe Use `classDirectories.from` instead of `classDirectories` – farmerbb Jul 08 '20 at 20:48
it would be better if someone can direct me where to use this code – jknair0 Apr 01 '22 at 04:05

score 0 · Answer 2 · answered Sep 01 '17 at 19:24

After a few days, I figured out a solution to this problem. For those of you experiencing similar issues: In your intermediates folder there should be a tmp folder. This folder contains the .class files for the Kotlin files. If you change the path of fileTree(dir: "${buildDir}/intermediates/classes/debug", excludes: fileFilter) to where those class files are located, Jacoco will generate code coverage for you! Please note that you will not be able to see a full, line-by-line overview of your coverage using this method.

but why? Does't it work with -> {buildDir}/tmp/kotlin-classes/universalDebugAndroidTest/ path? — Astha Garg, Nov 25 '21 at 13:26

Mahozad · Answer 3 · 2022-05-04T08:56:31.207

0

Try using the new kotlinx-kover Gradle plugin compatible with JaCoCo and IntelliJ.
It resolves the problem with inline functions reported as 0% and maybe more.

plugins {
     id("org.jetbrains.kotlinx.kover") version "0.5.0"
}

Once applied, the plugin can be used out of the box without additional configuration.

Watch its YouTube announcement video and also track its roadmap from this youtrack issue.

edited May 04 '22 at 08:56

answered Nov 06 '21 at 14:02

Mahozad

18,032
13
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JaCoCo returning 0% Coverage with Kotlin and Android 3.0

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