Fail if there are duplicate project names

build.gradle.kts

@@ -1,4 +1,5 @@
 import com.gradleup.librarian.gradle.Librarian
+import nmcp.NmcpAggregationExtension
 
 plugins {
     alias(libs.plugins.kgp).apply(false)
@@ -37,3 +38,7 @@ tasks.named("librarianStaticContent").configure {
     }
 }
 
+extensions.getByType(NmcpAggregationExtension::class.java).localRepository {
+    this.name = "test"
+    this.path = "build/m2"
+}

gradle/libs.versions.toml

@@ -3,14 +3,15 @@ kgp = "2.3.0"
 ksp = "2.3.4"
 gratatouille-runtime = "0.2.1"
 gratatouille-plugin = "0.2.1"
+gradle-api = "8.8"
 
 [libraries]
 json = "org.jetbrains.kotlinx:kotlinx-serialization-json:1.9.0"
 okio = "com.squareup.okio:okio:3.16.4"
 okhttp = "com.squareup.okhttp3:okhttp:5.3.2"
 mockwebserver = "com.squareup.okhttp3:mockwebserver:5.3.2"
 #noinspection NewerVersionAvailable
-gradle-min = "dev.gradleplugins:gradle-api:8.8"
+gradle-min = { module = "dev.gradleplugins:gradle-api", version.ref = "gradle-api" }
 kotlin-test = { module = "org.jetbrains.kotlin:kotlin-test" }
 xmlutil = "io.github.pdvrieze.xmlutil:serialization:1.0.0-rc1"
 kgp = { module = "org.jetbrains.kotlin.jvm:org.jetbrains.kotlin.jvm.gradle.plugin", version.ref = "kgp" }
@@ -23,6 +24,6 @@ kgp = { id = "org.jetbrains.kotlin.jvm", version.ref = "kgp" }
 serialization = { id = "org.jetbrains.kotlin.plugin.serialization", version.ref = "kgp" }
 ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
 gratatouille = { id = "com.gradleup.gratatouille", version.ref = "gratatouille-plugin" }
-librarian = { id = "com.gradleup.librarian", version = "0.2.2-SNAPSHOT-6898196f1f9759091ae6fa9bbe84154ec28a9331" }
-nmcp = { id = "com.gradleup.nmcp", version = "1.3.0" }
-compat = { id = "com.gradleup.tapmoc", version = "0.3.3-SNAPSHOT-a7d9d3fed6e48f1a88966d81e753259dadfa9a9a" }
+librarian = { id = "com.gradleup.librarian", version = "0.2.2-SNAPSHOT-f89d61cb6d4bd03bb9f48d1c8220262c0d02094c" }
+nmcp = { id = "com.gradleup.nmcp", version = "1.4.2-SNAPSHOT-9cc65e0d486a8b82f8b2e3039455eeb24a4bfd6d" }
+compat = { id = "com.gradleup.tapmoc", version = "0.4.1-SNAPSHOT-86d664ab69b813963b91060ecce036be943088ed" }

librarian.root.properties

@@ -1,5 +1,6 @@
 java.compatibility=17
-kotlin.compatibility=1.9.0
+# overridden for the Gradle plugin
+kotlin.compatibility=2.2.0
 
 kdoc.olderVersions=
 kdoc.artifactId=kdoc

nmcp-tasks/build.gradle.kts

@@ -1,4 +1,5 @@
 import com.gradleup.librarian.gradle.Librarian
+import tapmoc.TapmocExtension
 
 plugins {
     alias(libs.plugins.kgp)

nmcp/build.gradle.kts

@@ -1,4 +1,6 @@
 import com.gradleup.librarian.gradle.Librarian
+import kotlin.jvm.java
+import tapmoc.TapmocExtension
 
 plugins {
     alias(libs.plugins.kgp)
@@ -7,6 +9,11 @@ plugins {
 }
 
 Librarian.module(project)
+extensions.getByType(TapmocExtension::class.java).apply {
+    // Override the default Kotlin version to work with older Gradle
+    kotlin("2.1.0")
+    //kotlin(kotlinVersionForGradle(libs.versions.gradle.api.get().toString()))
+}
 
 gratatouille {
     addDependencies = false
@@ -17,5 +24,11 @@ dependencies {
     gratatouille(project(":nmcp-tasks"))
     compileOnly(libs.gradle.min)
     implementation(libs.gratatouille.runtime)
+
     testImplementation(libs.kotlin.test)
+    testImplementation(gradleTestKit())
+}
+
+tasks.withType(Test::class.java).configureEach {
+    dependsOn(":nmcpPublishAggregationToTestRepository")
 }

nmcp/src/main/kotlin/nmcp/internal/DefaultNmcpAggregationExtension.kt

@@ -48,6 +48,17 @@ internal abstract class DefaultNmcpAggregationExtension(private val project: Pro
             inputFiles = allFiles,
             spec = spec,
         )
+
+        project.afterEvaluate {
+            val allNames = mutableSetOf<String>()
+            project.allprojects {
+                check (!allNames.contains(it.name.lowercase())) {
+                    "Nmcp: duplicate project name: '${it.name}'. This is usually resolved by setting your root project name in your settings.gradle[.kts] file: `rootProject.name = \"\${someUniqueName}\". " +
+                        "See https://github.com/gradle/gradle/issues/36167 for more details"
+                }
+                allNames.add(it.name.lowercase())
+            }
+        }
     }
 
     override fun centralPortal(action: Action<CentralPortalOptions>) {

nmcp/src/test/kotlin/DuplicateNameTest.kt

@@ -0,0 +1,24 @@
+import java.io.File
+import kotlin.test.Test
+import org.gradle.testkit.runner.GradleRunner
+
+class DuplicateNameTest {
+  @Test
+  fun duplicateName() {
+    val dst = File("build/testProject")
+    val src = File("testProjects/duplicate-name")
+
+    dst.deleteRecursively()
+    dst.mkdirs()
+
+    src.copyRecursively(dst, overwrite = true)
+
+      val result = GradleRunner.create()
+          .withProjectDir(dst)
+          .withArguments("nmcpZipAggregation")
+          .forwardOutput()
+          .buildAndFail()
+
+      assert(result.output.contains("duplicate project name"))
+  }
+}

nmcp/testProjects/duplicate-name/build.gradle.kts

@@ -0,0 +1,11 @@
+plugins {
+  id("org.jetbrains.kotlin.jvm").version("2.3.0").apply(false)
+  id("com.gradleup.nmcp.aggregation").version("1.4.2-SNAPSHOT")
+}
+
+group = "com.example"
+version = "1.0.0"
+
+dependencies {
+  nmcpAggregation(project(":duplicate-name"))
+}

nmcp/testProjects/duplicate-name/duplicate-name/build.gradle.kts

@@ -0,0 +1,14 @@
+plugins {
+  id("org.jetbrains.kotlin.jvm")
+  id("maven-publish")
+  id("com.gradleup.nmcp")
+  id("signing")
+}
+
+group = rootProject.group
+
+publishing {
+  publications.create("default", MavenPublication::class.java) {
+    from(components.getByName("java"))
+  }
+}

nmcp/testProjects/duplicate-name/duplicate-name/src/main/kotlin/hello.kt

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

nmcp/testProjects/duplicate-name/settings.gradle.kts

@@ -0,0 +1,10 @@
+// Change this to fix the build
+rootProject.name = "duplicate-name"
+pluginManagement {
+  listOf(repositories, dependencyResolutionManagement.repositories).forEach {
+    it.mavenCentral()
+    it.maven("../../../build/m2")
+  }
+}
+
+include(":duplicate-name")

scripts/update-repo.main.kts

@@ -5,19 +5,27 @@
 @file:Repository("https://storage.googleapis.com/gradleup/m2")
 @file:Repository("https://jitpack.io")
 //@file:Repository("file://~/.m2/repository")
-@file:DependsOn("com.gradleup.librarian:librarian-cli:0.2.2-SNAPSHOT-0cbca80f60a15a0f851a9cd468bfc352db316dd4")
+@file:DependsOn("com.gradleup.librarian:librarian-cli:0.2.2-SNAPSHOT-f89d61cb6d4bd03bb9f48d1c8220262c0d02094c")
 
 import com.gradleup.librarian.cli.updateRepo
 
-updateRepo(args) {
-    file("docs/src/content/docs/index.mdx") {
-        replacePluginVersion("com.gradleup.nmcp.settings")
-        replacePluginVersion("com.gradleup.nmcp.aggregation")
-        replacePluginVersion("com.gradleup.nmcp")
-    }
-    file("docs/src/content/docs/manual-configuration.mdx") {
-        replacePluginVersion("com.gradleup.nmcp.settings")
-        replacePluginVersion("com.gradleup.nmcp.aggregation")
-        replacePluginVersion("com.gradleup.nmcp")
-    }
-}
+updateRepo(
+    args,
+    setVersion = {
+        file("nmcp/testProjec/duplicate-name/build.gradle.kts") {
+            replacePluginVersion("com.gradleup.nmcp.aggregation")
+        }
+    },
+    setDocsVersion = {
+        file("docs/src/content/docs/index.mdx") {
+            replacePluginVersion("com.gradleup.nmcp.settings")
+            replacePluginVersion("com.gradleup.nmcp.aggregation")
+            replacePluginVersion("com.gradleup.nmcp")
+        }
+        file("docs/src/content/docs/manual-configuration.mdx") {
+            replacePluginVersion("com.gradleup.nmcp.settings")
+            replacePluginVersion("com.gradleup.nmcp.aggregation")
+            replacePluginVersion("com.gradleup.nmcp")
+        }
+    },
+)

settings.gradle.kts

@@ -7,9 +7,10 @@ pluginManagement {
             mavenCentral()
             maven("https://storage.googleapis.com/gradleup/m2") {
                 content {
-                    // gratatouille-processor is only used at build time and is safe to fetch as a snapshot
+                    // those dependencies are only used at build time and is safe to fetch as a snapshot
                     includeModule("com.gradleup.gratatouille", "gratatouille-processor")
                     includeModule("com.gradleup.tapmoc", "tapmoc-tasks")
+                    includeModule("com.gradleup.nmcp", "nmcp-tasks")
                 }
             }
         }