From a34b7ee4b79b3e4dae29098297bd946f3a9e4fe1 Mon Sep 17 00:00:00 2001
From: "Johnny Miller (ZA)" <johnnysviva@outlook.com>
Date: Fri, 12 Aug 2022 14:44:44 +0800
Subject: [PATCH] perf($Gradle): execute unit tests in parallel mode; supports
 JaCoCo

https://www.jvt.me/posts/2021/03/11/gradle-speed-parallel/
---
 build.gradle.kts | 55 ++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 48 insertions(+), 7 deletions(-)

diff --git a/build.gradle.kts b/build.gradle.kts
index d1f7cc91..8ffa7806 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,8 +1,10 @@
 import enforcer.rules.RequireGradleVersion
-import enforcer.rules.RequireJavaVersion
 import enforcer.rules.RequireJavaVendor
+import enforcer.rules.RequireJavaVersion
 import io.spring.gradle.dependencymanagement.dsl.DependencyManagementExtension
 import org.gradle.api.JavaVersion.VERSION_17
+import org.gradle.api.tasks.testing.logging.TestExceptionFormat.FULL
+import org.gradle.api.tasks.testing.logging.TestLogEvent.*
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 import org.springframework.boot.gradle.tasks.bundling.BootJar
 
@@ -10,6 +12,7 @@ plugins {
     java
     idea
     `java-library`
+    jacoco
     `maven-publish`
     kotlin("jvm")
     kotlin("kapt")
@@ -66,6 +69,7 @@ subprojects {
     apply {
         plugin("java")
         plugin("java-library")
+        plugin("jacoco")
         plugin("kotlin")
         plugin("kotlin-kapt")
         plugin("org.jetbrains.kotlin.plugin.spring")
@@ -90,18 +94,56 @@ subprojects {
         options.isFork = true
     }
 
-    tasks.withType<Test> {
-        useJUnitPlatform()
-    }
-
     // https://docs.gradle.org/current/userguide/performance.html#parallel_test_execution
     tasks.withType<Test>().configureEach {
-        // The normal approach is to use some number less than or equal to the number of CPU cores you have, such as this algorithm:
+        // The normal approach is to use some number less than or equal to the number of CPU cores you have,
+        // such as this algorithm:
         maxParallelForks = (Runtime.getRuntime().availableProcessors() / 2).takeIf { it > 0 } ?: 1
         // To fork a new test VM after a certain number of tests have run
         setForkEvery(100)
     }
 
+    // https://docs.gradle.org/current/dsl/org.gradle.api.tasks.testing.Test.html
+    tasks.withType<Test> {
+        // Configuration parameters to execute top-level classes in parallel but methods in the same thread
+        // https://www.jvt.me/posts/2021/03/11/gradle-speed-parallel/
+        systemProperties["junit.jupiter.execution.parallel.enabled"] = "true"
+        systemProperties["junit.jupiter.execution.parallel.mode.default"] = "concurrent"
+        systemProperties["junit.jupiter.execution.parallel.mode.classes.default"] = "concurrent"
+        // Discover and execute JUnit Platform-based tests
+        useJUnitPlatform()
+        failFast = true
+        // https://technology.lastminute.com/junit5-kotlin-and-gradle-dsl/
+        testLogging {
+            // set options for log level LIFECYCLE
+            events = mutableSetOf(FAILED, PASSED, SKIPPED, STANDARD_OUT)
+            exceptionFormat = FULL
+            showStandardStreams = true
+            showExceptions = true
+            showCauses = true
+            showStackTraces = true
+            // set options for log level DEBUG and INFO
+            debug {
+                events = mutableSetOf(FAILED, PASSED, SKIPPED, STANDARD_OUT)
+                exceptionFormat = FULL
+            }
+            info {
+                events = debug.events
+                exceptionFormat = debug.exceptionFormat
+            }
+        }
+        // report is always generated after tests run
+        finalizedBy(tasks.jacocoTestReport)
+    }
+
+    tasks.jacocoTestReport {
+        // tests are required to run before generating the report
+        dependsOn(tasks.test)
+        reports {
+            csv.required.set(true)
+        }
+    }
+
     // Disable for take of building Spring Boot executable jar for most of the subprojects,
     // Only bootstrap subproject needs it to be `true`.
     tasks.withType<BootJar> {
@@ -148,7 +190,6 @@ subprojects {
         // Testing
         testImplementation("org.springframework.boot:spring-boot-starter-test")
         testImplementation("org.mockito.kotlin:mockito-kotlin:$mockitoKotlinVersion")
-        testImplementation("org.jacoco:org.jacoco.agent:0.8.8")
     }
 
     configurations {