Implemented protype of Kover Aggregation Plugin

Relates #608

PR #644

Author: shanshin

README.md

@@ -113,6 +113,12 @@ in this case report will be generated for current project joined with `:another:
 
 **More examples of Gradle plugin applying can be found in [example folder](kover-gradle-plugin/examples)**
 
+## Kover Aggregated Plugin
+Kover Aggregated Plugin as a prototype of Gradle Settings plugin, created to simplify the setup of multi-project builds. 
+It is in its infancy, it is recommended to use it only for test or pet projects.
+
+Refer to the [documentation](https://kotlin.github.io/kotlinx-kover/gradle-plugin/aggregated.html) for details. 
+
 ## Kover CLI
 Standalone JVM application used for offline instrumentation and generation of human-readable reports.
 

build-logic/src/main/kotlin/kotlinx/kover/conventions/kover-publishing-conventions.gradle.kts

@@ -210,3 +210,8 @@ val Project.sourceSets: SourceSetContainer
 
 val SourceSetContainer.main: NamedDomainObjectProvider<SourceSet>
     get() = named<SourceSet>("main")
+
+signing {
+    // disable signing if private key isn't passed
+    isRequired = findProperty("libs.sign.key.private") != null
+}

kover-gradle-plugin/api/kover-gradle-plugin.api

@@ -1,3 +1,18 @@
+public abstract interface class kotlinx/kover/gradle/aggregation/settings/dsl/KoverSettingsExtension {
+	public abstract fun enableCoverage ()V
+	public abstract fun getReports ()Lkotlinx/kover/gradle/aggregation/settings/dsl/ReportsSettings;
+	public abstract fun reports (Lorg/gradle/api/Action;)V
+}
+
+public abstract interface class kotlinx/kover/gradle/aggregation/settings/dsl/ReportsSettings {
+	public abstract fun getExcludedClasses ()Lorg/gradle/api/provider/SetProperty;
+	public abstract fun getExcludedProjects ()Lorg/gradle/api/provider/SetProperty;
+	public abstract fun getExcludesAnnotatedBy ()Lorg/gradle/api/provider/SetProperty;
+	public abstract fun getIncludedClasses ()Lorg/gradle/api/provider/SetProperty;
+	public abstract fun getIncludedProjects ()Lorg/gradle/api/provider/SetProperty;
+	public abstract fun getIncludesAnnotatedBy ()Lorg/gradle/api/provider/SetProperty;
+}
+
 public final class kotlinx/kover/gradle/plugin/KoverGradlePlugin : org/gradle/api/Plugin {
 	public fun <init> ()V
 	public synthetic fun apply (Ljava/lang/Object;)V

kover-gradle-plugin/build.gradle.kts

@@ -42,6 +42,7 @@ val functionalTestImplementation = "functionalTestImplementation"
 
 dependencies {
     implementation(project(":kover-features-jvm"))
+    implementation(project(":kover-jvm-agent"))
     // exclude transitive dependency on stdlib, the Gradle version should be used
     compileOnly(kotlin("stdlib"))
     compileOnly(libs.gradlePlugin.kotlin)
@@ -52,6 +53,13 @@ dependencies {
 
     snapshotRelease(project(":kover-features-jvm"))
     snapshotRelease(project(":kover-jvm-agent"))
+
+    functionalTestImplementation(gradleTestKit())
+    // dependencies only for plugin's classpath to work with Kotlin Multi-Platform and Android plugins
+    functionalTestImplementation("org.jetbrains.kotlin:kotlin-gradle-plugin:$embeddedKotlinVersion")
+    functionalTestImplementation("org.jetbrains.kotlin:kotlin-compiler-embeddable:$embeddedKotlinVersion")
+    functionalTestImplementation("org.jetbrains.kotlin:kotlin-compiler-runner:$embeddedKotlinVersion")
+
 }
 
 kotlin {
@@ -70,7 +78,20 @@ val functionalTest by tasks.registering(Test::class) {
     useJUnitPlatform()
 
     dependsOn(tasks.collectRepository)
+
+    // While gradle testkit supports injection of the plugin classpath it doesn't allow using dependency notation
+    // to determine the actual runtime classpath for the plugin. It uses isolation, so plugins applied by the build
+    // script are not visible in the plugin classloader. This means optional dependencies (dependent on applied plugins -
+    // for example kotlin multiplatform) are not visible even if they are in regular gradle use. This hack will allow
+    // extending the classpath. It is based upon: https://docs.gradle.org/6.0/userguide/test_kit.html#sub:test-kit-classpath-injection
+    // Create a configuration to register the dependencies against
     doFirst {
+        val file = File(temporaryDir, "plugin-classpath.txt")
+        file.writeText(sourceSets["functionalTest"].compileClasspath
+            .filter { it.name.startsWith("stdlib") }
+            .joinToString("\n"))
+        systemProperties["plugin-classpath"] = file.absolutePath
+
         // basic build properties
         setSystemPropertyFromProject("kover.test.kotlin.version")
 
@@ -180,11 +201,6 @@ extensions.configure<Kover_publishing_conventions_gradle.KoverPublicationExtensi
     addPublication.set(false)
 }
 
-signing {
-    // disable signing if private key isn't passed
-    isRequired = findProperty("libs.sign.key.private") != null
-}
-
 gradlePlugin {
     website.set("https://github.com/Kotlin/kotlinx-kover")
     vcsUrl.set("https://github.com/Kotlin/kotlinx-kover.git")
@@ -199,3 +215,18 @@ gradlePlugin {
         }
     }
 }
+
+gradlePlugin {
+    website.set("https://github.com/Kotlin/kotlinx-kover")
+    vcsUrl.set("https://github.com/Kotlin/kotlinx-kover.git")
+
+    plugins {
+        create("KoverSettingsPlugin") {
+            id = "org.jetbrains.kotlinx.kover.aggregation"
+            implementationClass = "kotlinx.kover.gradle.aggregation.settings.KoverSettingsGradlePlugin"
+            displayName = "Gradle Settings Plugin for Kotlin Code Coverage Tools"
+            description = "Evaluate code coverage for projects written in Kotlin, applied only inside settings.gradle[.kts] files"
+            tags.addAll("kover", "kotlin", "coverage", "settings plugin")
+        }
+    }
+}

kover-gradle-plugin/docs/aggregated.md

@@ -0,0 +1,73 @@
+# Kover Aggregated Plugin
+
+## Quickstart
+This plugin is a prototype for testing ideas related to an alternative configuration method.
+
+The main difference from the existing Kover Gradle Plugin is the reactive content of the report: only those classes and tests that were compiled and executed within the same build get into the report.
+
+To use the plugin, just add into a `settings.gradle.kts` file 
+```kotlin
+plugins {
+    id("org.jetbrains.kotlinx.kover.aggregation") version "0.8.1"
+}
+```
+**There is no need to apply Kover plugin in other places, the `org.jetbrains.kotlinx.kover` plug-in should not be applied anywhere.**
+
+To measure coverage you should pass special `-Pkover` argument to Gradle CLI command and call the command to generate the corresponding report `koverHtmlReport` or `koverXmlReport`.
+Example, if you want to measure the coverage of the `test` task:
+```shell
+./gradlew test -Pkover koverHtmlReport
+```
+
+Only those classes that were compiled as part of the current Gradle build are included in the report.
+If no compilation tasks were called in the build, the report will be empty.
+
+The report covers only those tests that were run as part of the current build.
+If no tests were called in the assembly, then the coverage for all classes will be 0.
+
+## Configuring
+At the moment, Kover Settings Plugin allows to configure reports minimally.
+
+There are two ways to configure, using a build script in `settings.gradle.kts` and CLI
+
+Acceptable settings in `settings.gradle.kts` and their equivalent in CLI
+```kotlin
+kover {
+    // -Pkover
+    enableCoverage()
+    
+    reports {
+        // -Pkover.projects.includes=:a
+        includedProjects.add(":a")
+        
+        // -Pkover.projects.excludes=:b
+        excludedProjects.add(":b")
+
+        // -Pkover.classes.includes=classes.to.exclude.*
+        includedClasses.add("classes.to.include.*")
+
+        // -Pkover.classes.excludes=classes.to.include.*
+        excludedClasses.add("classes.to.exclude.*")
+
+        // -Pkover.classes.excludesAnnotated=*.Generated*
+        excludesAnnotatedBy.add("*.Generated*")
+        
+        // -Pkover.classes.includesAnnotated=*Included*
+        includesAnnotatedBy.add("*Included*")
+    }
+}
+```
+
+For example, the following setting is in `settings.gradle.kts`
+```kotlin
+kover {
+    enableCoverage()
+    
+    reports {
+        excludedClasses.add("org.test.MyClass*")
+    }
+}
+```
+fully equivalent to Gradle CLI arguments `-Pkover -Pkover.classes.excludes=org.test.MyClass*`
+
+**Any of the specified settings or DSL is preliminary and can be deleted or changed without maintaining backward compatibility**

kover-gradle-plugin/src/functionalTest/kotlin/kotlinx/kover/gradle/plugin/test/functional/cases/ReportsCachingTests.kt

@@ -3,7 +3,6 @@
  */
 package kotlinx.kover.gradle.plugin.test.functional.cases
 
-import kotlinx.kover.gradle.plugin.commons.CoverageToolVendor
 import kotlinx.kover.gradle.plugin.test.functional.framework.configurator.*
 import kotlinx.kover.gradle.plugin.test.functional.framework.starter.*
 

kover-gradle-plugin/src/functionalTest/kotlin/kotlinx/kover/gradle/plugin/test/functional/cases/SettingsPluginTests.kt

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2017-2024 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.kover.gradle.plugin.test.functional.cases
+
+import kotlinx.kover.gradle.plugin.test.functional.framework.checker.CheckerContext
+import kotlinx.kover.gradle.plugin.test.functional.framework.starter.TemplateTest
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+internal class SettingsPluginTests {
+    @TemplateTest("settings-plugin", [":tasks"])
+    fun CheckerContext.testNoReportTasks() {
+        taskOutput(":tasks") {
+            assertFalse("koverXmlReport" in this)
+            assertFalse("koverHtmlReport" in this)
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["test"])
+    fun CheckerContext.testNoInstrumentation() {
+        checkDefaultBinReport(false)
+        subproject("subproject") {
+            checkDefaultBinReport(false)
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["-Pkover", ":tasks", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testHasReportTasks() {
+        taskOutput(":tasks") {
+            assertTrue("koverXmlReport" in this)
+            assertTrue("koverHtmlReport" in this)
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["-Pkover", "koverXmlReport", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testNoCompilations() {
+        xmlReport {
+            classCounter("tests.settings.root.RootClass").assertAbsent()
+            classCounter("tests.settings.subproject.SubprojectClass").assertAbsent()
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["-Pkover", ":compileKotlin", "koverXmlReport", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testCompilationOnlyForRoot() {
+        xmlReport {
+            classCounter("tests.settings.root.RootClass").assertFullyMissed()
+            classCounter("tests.settings.subproject.SubprojectClass").assertAbsent()
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["-Pkover", ":subproject:compileKotlin", ":test", "koverXmlReport", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testRootAndOnlyCompileSubproject() {
+        xmlReport {
+            classCounter("tests.settings.root.RootClass").assertFullyCovered()
+            classCounter("tests.settings.subproject.SubprojectClass").assertFullyMissed()
+        }
+    }
+
+
+    @TemplateTest("settings-plugin", ["-Pkover", "test", "koverXmlReport", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testAll() {
+        xmlReport {
+            classCounter("tests.settings.root.RootClass").assertFullyCovered()
+            classCounter("tests.settings.subproject.SubprojectClass").assertFullyCovered()
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["-Pkover", "test", "koverXmlReport", "-Pkover.projects.excludes=:subproject", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testExcludeSubproject() {
+        xmlReport {
+            classCounter("tests.settings.root.RootClass").assertFullyCovered()
+            classCounter("tests.settings.subproject.SubprojectClass").assertAbsent()
+        }
+    }
+
+    @TemplateTest("settings-plugin", ["-Pkover", "test", "koverXmlReport", "-Pkover.classes.excludes=tests.settings.subproject.*", "-Dorg.gradle.unsafe.isolated-projects=true", "--configuration-cache", "--build-cache"])
+    fun CheckerContext.testExcludeClasses() {
+        xmlReport {
+            classCounter("tests.settings.root.RootClass").assertFullyCovered()
+            classCounter("tests.settings.subproject.SubprojectClass").assertAbsent()
+        }
+    }
+}

kover-gradle-plugin/src/functionalTest/kotlin/kotlinx/kover/gradle/plugin/test/functional/framework/writer/SettingsWriter.kt

@@ -15,6 +15,7 @@ internal fun FormattedWriter.writePluginManagement(language: ScriptLanguage,
     call("resolutionStrategy") {
         call("eachPlugin") {
             line("if (requested.id.id == \"org.jetbrains.kotlinx.kover\") { useVersion(\"$koverVersion\") }")
+            line("if (requested.id.id == \"org.jetbrains.kotlinx.kover.aggregation\") { useVersion(\"$koverVersion\") }")
             if (overrideKotlinVersion != null) {
                 line("if (requested.id.id == \"org.jetbrains.kotlin.jvm\") useVersion(\"$overrideKotlinVersion\")")
                 line("if (requested.id.id == \"org.jetbrains.kotlin.multiplatform\") useVersion(\"$overrideKotlinVersion\")")

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/build.gradle.kts

@@ -0,0 +1,8 @@
+plugins {
+    kotlin("jvm") version ("2.0.0")
+}
+
+dependencies {
+    testImplementation(kotlin("test"))
+}
+

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/settings.gradle.kts

@@ -0,0 +1,20 @@
+pluginManagement {
+    repositories {
+        gradlePluginPortal()
+        mavenCentral()
+    }
+}
+
+plugins {
+    id("org.jetbrains.kotlinx.kover.aggregation") version "SNAPSHOT"
+}
+
+buildCache {
+    local {
+        directory = "$settingsDir/build-cache"
+    }
+}
+
+rootProject.name = "settings-plugin"
+
+include(":subproject")

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/src/main/kotlin/RootClass.kt

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2017-2024 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package tests.settings.root
+
+class RootClass {
+    fun action() {
+        println("It's root class")
+    }
+}

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/src/test/kotlin/RootTest.kt

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2017-2024 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package tests.settings.root
+
+import kotlin.test.Test
+
+class RootTest {
+    @Test
+    fun test() {
+        RootClass().action()
+    }
+}

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/subproject/build.gradle.kts

@@ -0,0 +1,7 @@
+plugins {
+    kotlin("jvm")
+}
+
+dependencies {
+    testImplementation(kotlin("test"))
+}

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/subproject/src/main/kotlin/SubprojectClass.kt

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2017-2024 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package tests.settings.subproject
+
+class SubprojectClass {
+    fun action() {
+        println("It's class from the subproject")
+    }
+}

kover-gradle-plugin/src/functionalTest/templates/builds/settings-plugin/subproject/src/test/kotlin/ATest.kt

@@ -0,0 +1,10 @@
+package tests.settings.subproject
+
+import kotlin.test.Test
+
+class SubprojectTest {
+    @Test
+    fun test() {
+        SubprojectClass().action()
+    }
+}