configured pitest mutation testing

build.gradle

@@ -7,6 +7,7 @@ plugins {
     id "org.owasp.dependencycheck" version "7.1.2"
     id "com.diffplug.spotless" version "6.10.0"
     id 'jacoco'
+    id 'info.solidsoft.pitest' version '1.7.4'
     id 'se.patrikerdes.use-latest-versions' version '0.2.18'
     id 'com.github.ben-manes.versions' version '0.42.0'
 }
@@ -72,6 +73,8 @@ dependencies {
     testImplementation 'org.testcontainers:postgresql'
     testImplementation 'com.tngtech.archunit:archunit-junit5:1.0.0-rc1'
     testImplementation 'io.rest-assured:spring-mock-mvc'
+    testImplementation 'org.hamcrest:hamcrest-core:2.2'
+    testImplementation 'org.pitest:pitest-junit5-plugin:1.0.0'
 }
 
 dependencyManagement {
@@ -213,6 +216,36 @@ jacocoTestCoverageVerification {
     }
 }
 
+// pitest mutation testing
+pitest {
+    targetClasses = ['net.hostsharing.hsadminng.**']
+    excludedClasses = [
+            'net.hostsharing.hsadminng.config.**',
+            'net.hostsharing.hsadminng.generated.**'
+    ]
+
+    targetTests = ['net.hostsharing.hsadminng.**.*UnitTest', 'net.hostsharing.hsadminng.**.*RestTest']
+    excludedTestClasses = ['**AcceptanceTest*', '**IntegrationTest*']
+
+    pitestVersion = '1.9.0'
+    junit5PluginVersion = '1.0.0'
+
+    threads = 4
+
+    // As Java unit tests are pretty pointless in our case, this maybe makes not much sense.
+    mutationThreshold = 31
+    coverageThreshold = 44
+    testStrengthThreshold = 76
+
+    outputFormats = ['XML', 'HTML']
+    timestampedReports = false
+}
+project.tasks.check.dependsOn(project.tasks.pitest)
+project.tasks.pitest.doLast {
+    println "PiTest Mutation Report: file:///${project.rootDir}/build/reports/pitest/index.html"
+}
+
+
 // Dependency Versions Upgrade
 useLatestVersions {
     finalizedBy check