Add more integration tests

.github/workflows/build-pull-request.yaml

@@ -8,3 +8,7 @@ jobs:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 #v4.2.2
       - run: |
           ./gradlew build
+          ./gradlew -p tests build
+          ./gradlew -p test-kgp-1-9 verifyCompatibility
+          sed -i.bak 's/.version("1.9.0")/.version("2.2.0")/' test-kgp-1-9/build.gradle.kts
+          ./gradlew -p test-kgp-1-9 verifyCompatibility

.gitignore

@@ -1,6 +1,7 @@
 .kotlin
 .fleet
 .gradle
+*.bak
 
 # Build outputs
 build

test-kgp-1-9/build.gradle.kts

@@ -0,0 +1,135 @@
+import cast.cast
+import com.nfeld.jsonpathkt.kotlinx.resolvePathOrNull
+import java.util.zip.ZipInputStream
+import kotlinx.metadata.jvm.KotlinModuleMetadata
+import kotlinx.metadata.jvm.UnstableMetadataApi
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonArray
+import kotlinx.serialization.json.jsonPrimitive
+import org.objectweb.asm.ClassReader
+import org.objectweb.asm.ClassVisitor
+import org.objectweb.asm.Opcodes
+
+plugins {
+  id("org.jetbrains.kotlin.jvm").version("1.9.0")
+  id("com.gradleup.compat.patrouille")
+  id("maven-publish")
+}
+
+buildscript {
+  dependencies {
+    classpath("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.0")
+    classpath("com.eygraber:jsonpathkt-kotlinx:3.0.2")
+    classpath("net.mbonnin.cast:cast:0.0.1")
+    classpath("org.jetbrains.kotlinx:kotlinx-metadata-jvm:0.9.0")
+    classpath("org.ow2.asm:asm:9.8")
+  }
+}
+
+compatPatrouille {
+  java(11)
+  kotlin("1.9.0")
+}
+abstract class VerifyCompatibility : DefaultTask() {
+  @get:InputFiles
+  abstract val m2Dir: ConfigurableFileCollection
+
+  /**
+   * Verifies that:
+   * - Gradle metadata contains has "org.gradle.jvm.version" set to "11"
+   * - The .class files have a version of 55 (java 11).
+   * - The .kotlin_module files have a Kotlin version of 1.9.0.
+   *
+   * A future version could test KMP.
+   * .klib files can be read using "org.jetbrains.kotlin:kotlin-util-klib".
+   * Not sure how to read the commonMetadata .jar artifact, though; it's a .jar that contains .kn data.
+   * Interestingly, when using KMP, "org.gradle.jvm.version" is not set, not really sure why.
+   */
+  @OptIn(UnstableMetadataApi::class)
+  @TaskAction
+  fun taskAction() {
+    val moduleFiles = m2Dir.files.filter { it.extension == "module" }.toList()
+
+    check(moduleFiles.size == 1) {
+      "Expected exactly one module file, got ${moduleFiles.size}: $moduleFiles"
+    }
+
+    moduleFiles.single().readText().let {
+      Json.parseToJsonElement(it)
+    }.resolvePathOrNull("$.variants.*.attributes[\"org.gradle.jvm.version\"]")!!
+      .cast<JsonArray>()
+      .map {
+        it.jsonPrimitive.content
+      }
+      .forEach {
+        check(it == "11") {
+          "Expected all modules to be built with Java 11, got $it"
+        }
+      }
+
+    val jarFiles = m2Dir.files.filter { it.extension == "jar" }.toList()
+    check(moduleFiles.size == 1) {
+      "Expected exactly one jar file, got ${jarFiles.size}: $jarFiles"
+    }
+    jarFiles.forEach { jarFile ->
+      ZipInputStream(jarFile.inputStream()).use { zis ->
+        var entry = zis.nextEntry
+        while (entry != null) {
+          if (entry.name.endsWith(".class")) {
+
+            ClassReader(zis).accept(object : ClassVisitor(Opcodes.ASM9) {
+              override fun visit(
+                version: Int,
+                access: Int,
+                name: String?,
+                signature: String?,
+                superName: String?,
+                interfaces: Array<out String?>?
+              ) {
+                check(version == 55) {
+                  "Expected class files be of version 55, got $version"
+                }
+              }
+            }, 0)
+          } else if (entry.name.endsWith(".kotlin_module")) {
+            val metadata = KotlinModuleMetadata.read(zis.readAllBytes())
+            metadata.version.apply {
+              check("$major.$minor.$patch" == "1.9.0") {
+                "Expected Kotlin version 1.9.0, got $major.$minor.$patch."
+              }
+            }
+          }
+          entry = zis.nextEntry
+        }
+      }
+    }
+  }
+}
+
+group = "com.example"
+version = "0.0.0-SNAPSHOT"
+publishing {
+  repositories {
+    maven {
+      name = "test"
+      url = uri(file("build/m2"))
+    }
+  }
+  publications {
+    create<MavenPublication>("maven") {
+      from(components["java"])
+    }
+  }
+}
+
+tasks.register("cleanM2", Delete::class.java) {
+  delete(file("build/m2"))
+}
+tasks.named("publishAllPublicationsToTestRepository") {
+  dependsOn("cleanM2")
+}
+tasks.register("verifyCompatibility", VerifyCompatibility::class.java) {
+  m2Dir.from(fileTree(layout.buildDirectory.dir("m2")))
+  dependsOn("publishAllPublicationsToTestRepository")
+}
+

test-kgp-1-9/gradle

@@ -0,0 +1 @@
+../gradle

test-kgp-1-9/settings.gradle.kts

@@ -0,0 +1,8 @@
+pluginManagement {
+  listOf(repositories, dependencyResolutionManagement.repositories).forEach {
+    it.mavenCentral()
+  }
+}
+
+
+includeBuild("../")

test-kgp-1-9/src/main/kotlin/hello.kt

@@ -0,0 +1 @@
+val hello = "Hello"

tests/check-api-dependencies/build.gradle.kts

@@ -10,6 +10,7 @@ compatPatrouille {
 }
 
 dependencies {
+  // Uncomment to make `compatPatrouilleCheckApiDependencies` fail because incompatible metadata was exposed to consumers.
 //  api("org.jetbrains.kotlin:kotlin-stdlib:2.1.21")
   api(libs.kotlinx.metadata)
 }