Kover is a set of solutions for collecting test coverage of Kotlin code compiled for JVM and Android platforms.

Kover Toolset:

• Kover Gradle Plugin
• Kover CLI
• Kover offline instrumentation
• Kover JVM agent
• Kover features artifact

For full information about latest stable release of Kover Gradle Plugin, please refer to the documentation of the latest stable release.

A beta version of the plugin is also available. The DSL of this version is unstable and can be changed after receiving feedback. Detailed documentation is in the process of being written, please refer to the migration guide.

• Collection of code coverage through JVM tests (JS and native targets are not supported yet).
• Generating HTML and XML reports.
• Support for Kotlin JVM, Kotlin Multiplatform projects.
• Support for Kotlin Android projects with build variants (instrumentation tests executing on the Android device are not supported yet).
• Support mixed Kotlin and Java sources
• Verification rules with bounds in the Gradle plugin to keep track of coverage.
• Using JaCoCo library in Gradle plugin as an alternative for coverage measuring and report generation.

The recommended way of applying Kover is with the plugins DSL.

Minimum supported version of Gradle is 6.8.

Add the following to your top-level build file:

plugins {
     id("org.jetbrains.kotlinx.kover") version "0.7.6"
}

plugins {
    id 'org.jetbrains.kotlinx.kover' version '0.7.6'
}

After you applied Kover Gradle plugin, Kover tasks will be created for generating reports and verification. E.g. to generate HTML report for non-Android project run ./gradlew koverHtmlReport - this will automatically start code compilation, execution of instrumented tests, and an HTML report will be generated with measurement results in the build folder.

It is also important that after applying Kover Gradle plugin, during the running tests, the classes are modified (instrumented) when loaded into the JVM which may lead to some performance degradation, or affect concurrent tests.

Legacy method of applying plugins can be used if you cannot use the plugins DSL for some reason.

buildscript {
    repositories {
        mavenCentral()
    }

    dependencies {
        classpath("org.jetbrains.kotlinx:kover-gradle-plugin:0.7.6")
    }
}

apply(plugin = "org.jetbrains.kotlinx.kover")

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'org.jetbrains.kotlinx:kover-gradle-plugin:0.7.6'
    }
}
  
apply plugin: 'org.jetbrains.kotlinx.kover'

You have to add dependency on the project, in which the report task will be run

dependencies {
  kover(project(":another:project"))
}

in this case report will be generated for current project joined with :another:project project.

More examples of Gradle plugin applying can be found in example folder

Standalone JVM application used for offline instrumentation and generation of human-readable reports.

Documentation of the latest stable release.

Offline instrumentation is the modification of class-files stored on disk to measure their coverage.

The ways of offline instrumentation and running of the instrumented applications are described in the documentation.

JVM agent is a jar file that modifies the bytecode of loaded into the JVM classes in order to measure coverage.

It was added in the beta version. documentations

A JVM dependency that allows to programmatically instrument class-files on a disk.

Documentation of the latest stable release

See Contributing Guidelines.