Support both KGP 2.3.0 and 2.3.20 at the same time

gradle/libs.versions.toml

@@ -20,7 +20,8 @@ gradle-api = "dev.gradleplugins:gradle-api:8.8"
 gratatouille-gradle-plugin = "com.gradleup.gratatouille:com.gradleup.gratatouille.gradle.plugin:0.2.2"
 jsonpath = "com.eygraber:jsonpathkt-kotlinx:3.0.2"
 jsonpathkt = "com.eygraber:jsonpathkt-kotlinx:3.0.2"
-kgp-compile-only = "org.jetbrains.kotlin:kotlin-gradle-plugin:2.3.20"
+kgp220 = "org.jetbrains.kotlin:kotlin-gradle-plugin:2.2.0"
+kgp2320 = "org.jetbrains.kotlin:kotlin-gradle-plugin:2.3.20"
 kotlin-gradle-plugin = { module = "org.jetbrains.kotlin:kotlin-gradle-plugin", version.ref = "kgp" }
 ksp-gradle-plugin = "com.google.devtools.ksp:com.google.devtools.ksp.gradle.plugin:2.3.3"
 librarian-gradle-plugin = "com.gradleup.librarian:librarian-gradle-plugin:0.2.2-SNAPSHOT-c2127df7d03b2946fc025bf67d31cac3e2c5a397"

librarian-gradle-plugin/build.gradle.kts

@@ -1,4 +1,5 @@
 import com.gradleup.librarian.gradle.Librarian
+import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
 
 plugins {
   id("org.jetbrains.kotlin.jvm")
@@ -32,9 +33,37 @@ dependencies {
 
   compileOnly(libs.gradle.api)
   compileOnly(libs.agp)
-  compileOnly(libs.kgp.compile.only)
+  compileOnly(libs.kgp220)
 
   testImplementation(kotlin("test"))
   testImplementation(gradleTestKit())
   testImplementation(libs.mockserver)
 }
+
+private fun addEdge(compilation: KotlinCompilation<*>, dependency: KotlinCompilation<*>) {
+  compilation.defaultSourceSet.dependencies {
+    compileOnly(dependency.output.classesDirs)
+  }
+}
+
+val mainCompilation = kotlin.target.compilations.getByName("main")
+
+mapOf(
+  "220" to setOf(libs.kgp220),
+  "2320" to setOf(libs.kgp2320)
+).forEach {
+  val compilation = kotlin.target.compilations.create("kgp-${it.key}")
+
+  addEdge(mainCompilation, compilation) // Needed to be able
+
+  tasks.jar {
+    from(compilation.output.classesDirs)
+  }
+  dependencies {
+    it.value.forEach {
+      add(compilation.compileOnlyConfigurationName, it)
+    }
+    // See https://issuetracker.google.com/issues/445209309
+    add(compilation.compileOnlyConfigurationName, libs.gradle.api)
+  }
+}

librarian-gradle-plugin/src/kgp-220/kotlin/com/gradleup/librarian/internal/bcv220.kt

@@ -0,0 +1,48 @@
+@file:OptIn(ExperimentalAbiValidation::class)
+
+package com.gradleup.librarian.internal
+
+import org.gradle.api.Project
+import org.jetbrains.kotlin.gradle.dsl.KotlinProjectExtension
+import org.jetbrains.kotlin.gradle.dsl.abi.AbiValidationExtension
+import org.jetbrains.kotlin.gradle.dsl.abi.AbiValidationMultiplatformExtension
+import org.jetbrains.kotlin.gradle.dsl.abi.ExperimentalAbiValidation
+
+fun Project.configureBcv220(
+  excludePatterns: List<String> = emptyList(),
+) {
+  extensions.getByType(KotlinProjectExtension::class.java).apply {
+    val abiValidation = this.extensions.findByName("abiValidation") ?: error("No abiValidation extension found")
+
+    when (abiValidation) {
+      is AbiValidationExtension -> {
+        abiValidation.enabled.set(true)
+        abiValidation.filters {
+          it.excluded.byNames.addAll(excludePatterns)
+        }
+      }
+
+      is AbiValidationMultiplatformExtension -> {
+        abiValidation.enabled.set(true)
+        abiValidation.filters {
+          it.excluded.byNames.addAll(excludePatterns)
+        }
+      }
+
+      else -> error("Librarian: unknown abiValidation extension type: '${abiValidation.javaClass.name}'")
+    }
+
+    /**
+     * Compatibility tasks to not break the brain muscle
+     */
+    tasks.named("build") {
+      it.dependsOn("checkLegacyAbi")
+    }
+    tasks.register("apiDump") {
+      it.dependsOn("updateLegacyAbi")
+    }
+    tasks.register("apiCheck") {
+      it.dependsOn("checkLegacyAbi")
+    }
+  }
+}

librarian-gradle-plugin/src/kgp-2320/kotlin/com/gradleup/librarian/internal/bcv2320.kt

@@ -0,0 +1,51 @@
+@file:OptIn(ExperimentalAbiValidation::class)
+
+package com.gradleup.librarian.internal
+
+import org.gradle.api.Project
+import org.jetbrains.kotlin.gradle.dsl.KotlinProjectExtension
+import org.jetbrains.kotlin.gradle.dsl.abi.AbiValidationExtension
+import org.jetbrains.kotlin.gradle.dsl.abi.AbiValidationMultiplatformExtension
+import org.jetbrains.kotlin.gradle.dsl.abi.ExperimentalAbiValidation
+
+fun Project.configureBcv2320(
+  excludePatterns: List<String> = emptyList(),
+) {
+  extensions.getByType(KotlinProjectExtension::class.java).apply {
+    val abiValidation = this.extensions.findByName("abiValidation") ?: error("No abiValidation extension found")
+
+    when (abiValidation) {
+      is AbiValidationExtension -> {
+        abiValidation.enabled.set(true)
+        abiValidation.filters {
+          it.exclude.byNames.addAll(excludePatterns)
+        }
+      }
+
+      is AbiValidationMultiplatformExtension -> {
+        abiValidation.enabled.set(true)
+        abiValidation.filters {
+          it.exclude.byNames.addAll(excludePatterns)
+        }
+      }
+
+      else -> error("Librarian: unknown abiValidation extension type: '${abiValidation.javaClass.name}'")
+    }
+
+    /**
+     * Compatibility tasks to not break the brain muscle
+     */
+    tasks.register("apiDump") {
+      it.dependsOn("updateKotlinAbi")
+      it.doLast {
+        println("`apiDump` is deprecated. Use `updateKotlinAbi` instead")
+      }
+    }
+    tasks.register("apiCheck") {
+      it.dependsOn("checkKotlinAbi")
+      it.doLast {
+        println("`apiCheck` is deprecated. Use `updateKotlinAbi` instead")
+      }
+    }
+  }
+}

librarian-gradle-plugin/src/main/kotlin/com/gradleup/librarian/gradle/bcv.kt

@@ -3,68 +3,23 @@
 package com.gradleup.librarian.gradle
 
 import com.gradleup.librarian.core.tooling.semVerOrThrow
+import com.gradleup.librarian.internal.configureBcv220
+import com.gradleup.librarian.internal.configureBcv2320
 import org.gradle.api.Project
-import org.jetbrains.kotlin.gradle.dsl.KotlinProjectExtension
-import org.jetbrains.kotlin.gradle.dsl.abi.AbiValidationExtension
-import org.jetbrains.kotlin.gradle.dsl.abi.AbiValidationMultiplatformExtension
 import org.jetbrains.kotlin.gradle.dsl.abi.ExperimentalAbiValidation
 import org.jetbrains.kotlin.gradle.plugin.getKotlinPluginVersion
 
 fun Project.configureBcv(
   warnIfMissing: Boolean = true,
   excludePatterns: List<String> = emptyList(),
 ) {
-  extensions.getByType(KotlinProjectExtension::class.java).apply {
-    val abiValidation = this.extensions.findByName("abiValidation")
+  // See https://kotlinlang.org/docs/whatsnew2320.html#improvements-to-binary-compatibility-validation-in-kgp
+  val kgpVersion = this@configureBcv.getKotlinPluginVersion().semVerOrThrow()
 
-    if (abiValidation != null) {
-      when (abiValidation) {
-        is AbiValidationExtension -> {
-          abiValidation.enabled.set(true)
-          abiValidation.filters {
-            it.exclude.byNames.addAll(excludePatterns)
-          }
-        }
-        is AbiValidationMultiplatformExtension -> {
-          abiValidation.enabled.set(true)
-          abiValidation.filters {
-            it.exclude.byNames.addAll(excludePatterns)
-          }
-        }
-        else -> error("Librarian: unknown abiValidation extension type: '${abiValidation.javaClass.name}'")
-      }
-
-      // See https://kotlinlang.org/docs/whatsnew2320.html#improvements-to-binary-compatibility-validation-in-kgp
-      val kgpVersion = this@configureBcv.getKotlinPluginVersion().semVerOrThrow()
-
-      /**
-       * Compatibility tasks to not break the brain muscle
-       */
-      if (kgpVersion >= "2.3.20".semVerOrThrow()) {
-        tasks.register("apiDump") {
-          it.dependsOn("updateKotlinAbi")
-          it.doLast {
-            println("`apiDump` is deprecated. Use `updateKotlinAbi` instead")
-          }
-        }
-        tasks.register("apiCheck") {
-          it.dependsOn("checkKotlinAbi")
-          it.doLast {
-            println("`apiCheck` is deprecated. Use `updateKotlinAbi` instead")
-          }
-        }
-      } else {
-        tasks.named("build") {
-          it.dependsOn("checkLegacyAbi")
-        }
-        tasks.register("apiDump") {
-          it.dependsOn("updateLegacyAbi")
-        }
-        tasks.register("apiCheck") {
-          it.dependsOn("checkLegacyAbi")
-        }
-      }
-    } else {
+  when {
+    kgpVersion >= "2.3.20".semVerOrThrow() -> configureBcv2320(excludePatterns)
+    kgpVersion >= "2.2.0".semVerOrThrow() -> configureBcv220(excludePatterns)
+    else -> {
       if (warnIfMissing) {
         println("Librarian: BCV is only configured by default if using KGP 2.2+ (currently detected is '${getKotlinPluginVersion()}'). Set bcv.warn=false in your librarian.root.properties file to remove this warning.")
       }