Reporting code coverage with JaCoCo Sample
You can open this sample inside an IDE using the IntelliJ native importer or Eclipse Buildship. |
This sample shows how to test Java projects with JaCoCo in Gradle.
To collect code coverage across multiple subprojects, we need to setup two aspects. First, the projects that run the tests and collect the code coverage data:
plugins {
id 'java'
id 'jacoco'
}
version = '1.0.2'
group = 'org.gradle.sample'
repositories {
jcenter()
}
tasks.named("test") {
useJUnitPlatform()
}
dependencies {
testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.0'
testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine'
}
// Do not generate reports for individual projects
tasks.named("jacocoTestReport") {
enabled = false
}
// Share sources folder with other projects for aggregated JaCoCo reports
configurations.create('transitiveSourcesElements') {
visible = false
canBeResolved = false
canBeConsumed = true
extendsFrom(configurations.implementation)
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage, Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category, Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named(DocsType, 'source-folders'))
}
sourceSets.main.java.srcDirs.forEach {
outgoing.artifact(it)
}
}
// Share the coverage data to be aggregated for the whole product
configurations.create('coverageDataElements') {
visible = false
canBeResolved = false
canBeConsumed = true
extendsFrom(configurations.implementation)
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage, Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category, Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named(DocsType, 'jacoco-coverage-data'))
}
// This will cause the test task to run if the coverage data is requested by the aggregation task
outgoing.artifact(tasks.named("test").map { task ->
task.extensions.getByType(JacocoTaskExtension).destinationFile
})
}
plugins {
java
jacoco
}
version = "1.0.2"
group = "org.gradle.sample"
repositories {
jcenter()
}
tasks.test {
useJUnitPlatform()
}
dependencies {
testImplementation("org.junit.jupiter:junit-jupiter-api:5.7.0")
testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine")
}
// Do not generate reports for individual projects
tasks.jacocoTestReport {
enabled = false
}
// Share sources folder with other projects for aggregated JaCoCo reports
configurations.create("transitiveSourcesElements") {
isVisible = false
isCanBeResolved = false
isCanBeConsumed = true
extendsFrom(configurations.implementation.get())
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("source-folders"))
}
sourceSets.main.get().java.srcDirs.forEach {
outgoing.artifact(it)
}
}
// Share the coverage data to be aggregated for the whole product
configurations.create("coverageDataElements") {
isVisible = false
isCanBeResolved = false
isCanBeConsumed = true
extendsFrom(configurations.implementation.get())
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("jacoco-coverage-data"))
}
// This will cause the test task to run if the coverage data is requested by the aggregation task
outgoing.artifact(tasks.test.map { task ->
task.extensions.getByType<JacocoTaskExtension>().destinationFile!!
})
}
Here we do the setup in a convention plugin called myproject.java-conventions
which we apply to all our application and library projects.
Here, the build is setup to run tests using JUnit5 and we apply the jacoco
plugin to collect the code coverage.
With the plugin applied, it automatically attaches itself to the test
task to collect the code coverage.
Please refer to the JaCoCo chapter for more details on the plugin configuration.
Second, to generate a report spanning all our tested projects, we introduce and additional project code-coverage-report
that collects source files and coverage data from all its dependent projects.
This is setup in a second convention plugin plugin called myproject.jacoco-aggregation
which provides a task called codeCoverageReport
to generate the aggregated report.
plugins {
id 'java'
id 'jacoco'
}
repositories {
jcenter()
}
// A resolvable configuration to collect source code
def sourcesPath = configurations.create("sourcesPath") {
visible = false
canBeResolved = true
canBeConsumed = false
extendsFrom(configurations.implementation)
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage, Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category, Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named(DocsType, 'source-folders'))
}
}
// A resolvable configuration to collect JaCoCo coverage data
def coverageDataPath = configurations.create("coverageDataPath") {
visible = false
canBeResolved = true
canBeConsumed = false
extendsFrom(configurations.implementation)
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage, Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category, Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named(DocsType, 'jacoco-coverage-data'))
}
}
// Task to gather code coverage from multiple subprojects
def codeCoverageReport = tasks.register('codeCoverageReport', JacocoReport) {
additionalClassDirs(configurations.runtimeClasspath)
additionalSourceDirs(sourcesPath.incoming.artifactView { lenient(true) }.files)
executionData(coverageDataPath.incoming.artifactView { lenient(true) }.files.filter { it.exists() })
reports {
// xml is usually used to integrate code coverage with
// other tools like SonarQube, Coveralls or Codecov
xml.enabled true
// HTML reports can be used to see code coverage
// without any external tools
html.enabled true
}
}
// Make JaCoCo report generation part of the 'check' lifecycle phase
tasks.named("check") {
dependsOn(codeCoverageReport)
}
plugins {
java
jacoco
}
repositories {
jcenter()
}
// A resolvable configuration to collect source code
val sourcesPath: Configuration by configurations.creating {
isVisible = false
isCanBeResolved = true
isCanBeConsumed = false
extendsFrom(configurations.implementation.get())
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("source-folders"))
}
}
// A resolvable configuration to collect JaCoCo coverage data
val coverageDataPath: Configuration by configurations.creating {
isVisible = false
isCanBeResolved = true
isCanBeConsumed = false
extendsFrom(configurations.implementation.get())
attributes {
attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("jacoco-coverage-data"))
}
}
// Task to gather code coverage from multiple subprojects
val codeCoverageReport by tasks.registering(JacocoReport::class) {
additionalClassDirs(configurations.runtimeClasspath.get())
additionalSourceDirs(sourcesPath.incoming.artifactView { lenient(true) }.files)
executionData(coverageDataPath.incoming.artifactView { lenient(true) }.files.filter { it.exists() })
reports {
// xml is usually used to integrate code coverage with
// other tools like SonarQube, Coveralls or Codecov
xml.isEnabled = true
// HTML reports can be used to see code coverage
// without any external tools
html.isEnabled = true
}
}
// Make JaCoCo report generation part of the 'check' lifecycle phase
tasks.check {
dependsOn(codeCoverageReport)
}
Running the tests and generate the report:
$ ./gradlew codeCoverageReport BUILD SUCCESSFUL 11 actionable tasks: 11 executed
For more information, see Testing in Java project chapter.