Jacoco coverage report of JUnit tests for a Gradle multiproject - gradle

Question

I am having difficulty combining Jacoco coverage report for a Gradle multi-project. For simplicity, I have created a simplified version that is structured as follows. I have the example project on GitHub.
+ root
+ common-a
+ common-b
+ project-a
+ project-b
The root, project-a, and project-b are Spring Boot applications. For some context, a project is meant to be a micro-service. Thus, the root project is simply running all micro-services in one process.
Not all projects have unit and/or integration tests. common-a subproject does not have any tests; common-b, project-a, and project-b projects have unit and integration tests; the root project has only integration tests.
The Jacoco coverage reports for subprojects are correct. It is able to combine both unit and integration tests into one cohesive report. However, the root project does not produce the cohesive report correctly.
I have tried a number of solutions with any success. Most of the solutions I found assume that the root project is simply a logical container and only the subprojects has test code. The results of the solutions I tried fall into one of the following three categories.
No Jacoco report generated at all; the build/reports/jacoco directory is missing
Partial Jacoco report for only sources in root project
Full Jacoco coverage report for root and subproject but 0% coverage; it is supposed to be 100% coverage
The following is the current build.gradle file.
buildscript {
repositories {
jcenter()
}
dependencies {
classpath("org.springframework.boot:spring-boot-gradle-plugin:1.3.5.RELEASE")
}
}
// settings for all projects
allprojects {
apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
apply plugin: 'io.spring.dependency-management'
apply plugin: 'jacoco'
group 'io.github.chriszhong'
sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8
repositories {
jcenter()
}
dependencyManagement {
imports {
mavenBom 'io.spring.platform:platform-bom:2.0.5.RELEASE'
}
}
sourceSets {
integrationTest {
compileClasspath += main.output + test.output
runtimeClasspath += main.output + test.output
java {
srcDir 'src/test-integration/java'
}
resources {
srcDir 'src/test-integration/resources'
}
}
}
configurations {
integrationTestCompile {
extendsFrom testCompile
}
integrationTestRuntime {
extendsFrom testRuntime
}
}
idea {
module {
testSourceDirs += sourceSets.integrationTest.java.srcDirs
testSourceDirs += sourceSets.integrationTest.resources.srcDirs
}
}
task integrationTest(type: Test) {
check {
dependsOn integrationTest
}
testClassesDir sourceSets.integrationTest.output.classesDir
classpath = sourceSets.integrationTest.runtimeClasspath
}
task testReport(type: TestReport) {
dependsOn check
destinationDir file("${reporting.baseDir}/unified/html")
reportOn test, integrationTest
}
task jacocoMerge(type: JacocoMerge) {
dependsOn check
executionData test, integrationTest
// temporary hack to fix a bug requiring that there be at least one test case in each source set for coverage data to be generated;
// it should be if there is at least one test case in any of the source sets
executionData = files(executionData.findAll({ it.exists() }))
}
tasks.withType(Test) {
reports {
html {
destination file("${reporting.baseDir}/${task.name}/html")
}
}
}
tasks.withType(JacocoReport) {
dependsOn jacocoMerge
executionData jacocoMerge.destinationFile
// temporary hack to fix a bug requiring that there be at least one test case in each source set for coverage data to be generated;
// it should be if there is at least one test case in any of the source sets
// executionData = files(executionData.findAll({ it.exists() }))
}
}
apply plugin: 'spring-boot'
version '1.0-SNAPSHOT'
dependencies {
compile project(':project-a')
compile project(':project-b')
testCompile 'junit:junit'
integrationTestCompile 'org.springframework.boot:spring-boot-starter-test'
}
testReport {
dependsOn check, subprojects.testReport
reportOn test, integrationTest, subprojects.test, subprojects.integrationTest
}
jacocoMerge {
dependsOn check, subprojects.jacocoMerge
executionData test, integrationTest, subprojects.jacocoMerge.destinationFile
// temporary hack to fix a bug requiring that there be at least one test case in each source set for coverage data to be generated;
// it should be if there is at least one test case in any of the source sets
executionData = files(executionData.findAll({ it.exists() }))
}
//jacocoTestReport {
// dependsOn jacocoMerge
// executionData test, integrationTest, subprojects.test, subprojects.integrationTest
// executionData jacocoMerge.destinationFile
// temporary hack to fix a bug requiring that there be at least one test case in each source set for coverage data to be generated;
// it should be if there is at least one test case in any of the source sets
// executionData = files(executionData.findAll({ it.exists() }))
// sourceDirectories = files(sourceSets.main.java.srcDirs, subprojects.sourceSets.main.java.srcDirs)
// classDirectories = files(sourceSets.main.output.classesDir, subprojects.sourceSets.main.output.classesDir)
//}
task wrapper(type: Wrapper) {
gradleVersion '2.14'
distributionUrl "https://services.gradle.org/distributions/gradle-${gradleVersion}-all.zip"
}
I have been banging my head at this problem for the past week and is at my wits end. I greatly appreciate any help I can get in resolving this problem.