Kotlin Facet: Detect module platform using Gradle plugin id/stdlib

artifact id (Gradle import)

idea/idea-maven/src/org/jetbrains/kotlin/idea/maven/KotlinMavenImporter.kt

@@ -105,7 +105,7 @@ class KotlinMavenImporter : MavenImporter(KOTLIN_PLUGIN_GROUP_ID, KOTLIN_PLUGIN_
         val compilerVersion = mavenProject.findPlugin(KotlinMavenConfigurator.GROUP_ID, KotlinMavenConfigurator.MAVEN_PLUGIN_ID)?.version
                               ?: return
         val kotlinFacet = module.getOrCreateFacet(modifiableModelsProvider)
-        kotlinFacet.configureFacet(compilerVersion, CoroutineSupport.DEFAULT, modifiableModelsProvider)
+        kotlinFacet.configureFacet(compilerVersion, CoroutineSupport.DEFAULT, null, modifiableModelsProvider)
         MavenProjectImportHandler.getInstances(module.project).forEach { it(kotlinFacet, mavenProject) }
     }
 

idea/src/org/jetbrains/kotlin/idea/configuration/KotlinGradleProjectDataService.kt

@@ -18,20 +18,25 @@ package org.jetbrains.kotlin.idea.configuration
 
 import com.intellij.openapi.externalSystem.model.DataNode
 import com.intellij.openapi.externalSystem.model.ProjectKeys
+import com.intellij.openapi.externalSystem.model.project.ModuleData
 import com.intellij.openapi.externalSystem.model.project.ProjectData
 import com.intellij.openapi.externalSystem.service.project.IdeModifiableModelsProvider
 import com.intellij.openapi.externalSystem.service.project.manage.AbstractProjectDataService
 import com.intellij.openapi.externalSystem.util.ExternalSystemApiUtil
 import com.intellij.openapi.project.Project
 import org.jetbrains.kotlin.config.CoroutineSupport
+import org.jetbrains.kotlin.config.TargetPlatformKind
 import org.jetbrains.kotlin.extensions.ProjectExtensionDescriptor
 import org.jetbrains.kotlin.idea.facet.KotlinFacet
 import org.jetbrains.kotlin.idea.facet.configureFacet
 import org.jetbrains.kotlin.idea.facet.getOrCreateFacet
+import org.jetbrains.kotlin.idea.facet.mavenLibraryId
 import org.jetbrains.kotlin.idea.inspections.gradle.findAll
 import org.jetbrains.kotlin.idea.inspections.gradle.findKotlinPluginVersion
+import org.jetbrains.kotlin.idea.inspections.gradle.getResolvedKotlinStdlibVersionByModuleData
 import org.jetbrains.plugins.gradle.model.data.BuildScriptClasspathData
 import org.jetbrains.plugins.gradle.model.data.GradleSourceSetData
+import org.jetbrains.plugins.gradle.service.project.data.ExternalProjectDataService
 import java.util.*
 
 interface GradleProjectImportHandler {
@@ -46,6 +51,23 @@ interface GradleProjectImportHandler {
 class KotlinGradleProjectDataService : AbstractProjectDataService<GradleSourceSetData, Void>() {
     override fun getTargetDataKey() = GradleSourceSetData.KEY
 
+    private fun detectPlatformByPlugin(moduleNode: DataNode<ModuleData>): TargetPlatformKind<*>? {
+        val projectNode = ExternalSystemApiUtil.findParent(moduleNode, ProjectKeys.PROJECT)
+        val externalProjectNode = ExternalSystemApiUtil.find(projectNode as DataNode<*>, ExternalProjectDataService.KEY)
+        return externalProjectNode?.let {
+            when (it.data.plugins.values.map { it.id }.firstOrNull { it.startsWith("kotlin-platform-") }) {
+                "kotlin-platform-jvm" -> TargetPlatformKind.Jvm.JVM_1_6
+                "kotlin-platform-js" -> TargetPlatformKind.JavaScript
+                "kotlin-platform-common" -> TargetPlatformKind.Default
+                else -> null
+            }
+        }
+    }
+
+    private fun detectPlatformByLibrary(moduleNode: DataNode<ModuleData>): TargetPlatformKind<*>? {
+        return TargetPlatformKind.ALL_PLATFORMS.firstOrNull { moduleNode.getResolvedKotlinStdlibVersionByModuleData(it.mavenLibraryId) != null }
+    }
+
     override fun postProcess(
             toImport: Collection<DataNode<GradleSourceSetData>>,
             projectData: ProjectData?,
@@ -59,11 +81,12 @@ class KotlinGradleProjectDataService : AbstractProjectDataService<GradleSourceSe
             val moduleNode = ExternalSystemApiUtil.findParent(sourceSetNode, ProjectKeys.MODULE)
             val compilerVersion = moduleNode?.findAll(BuildScriptClasspathData.KEY)?.firstOrNull()?.data?.let(::findKotlinPluginVersion)
                                   ?: continue
+            val platformKind = detectPlatformByPlugin(moduleNode) ?: detectPlatformByLibrary(moduleNode)
 
             val coroutinesProperty = findKotlinCoroutinesProperty(project)
 
             val kotlinFacet = ideModule.getOrCreateFacet(modelsProvider)
-            kotlinFacet.configureFacet(compilerVersion, coroutinesProperty, modelsProvider)
+            kotlinFacet.configureFacet(compilerVersion, coroutinesProperty, platformKind, modelsProvider)
             GradleProjectImportHandler.getInstances(project).forEach { it(kotlinFacet, sourceSetNode) }
         }
     }

idea/src/org/jetbrains/kotlin/idea/facet/facetUtils.kt

@@ -67,6 +67,9 @@ private fun getDefaultTargetPlatform(module: Module, rootModel: ModuleRootModel?
     if (getRuntimeLibraryVersions(module, rootModel, TargetPlatformKind.JavaScript).isNotEmpty()) {
         return TargetPlatformKind.JavaScript
     }
+    if (getRuntimeLibraryVersions(module, rootModel, TargetPlatformKind.Default).isNotEmpty()) {
+        return TargetPlatformKind.Default
+    }
     return TargetPlatformKind.Jvm.JVM_1_6
 }
 
@@ -153,10 +156,15 @@ fun Module.getOrCreateFacet(modelsProvider: IdeModifiableModelsProvider): Kotlin
     return facet
 }
 
-fun KotlinFacet.configureFacet(compilerVersion: String, coroutineSupport: CoroutineSupport, modelsProvider: IdeModifiableModelsProvider) {
+fun KotlinFacet.configureFacet(
+        compilerVersion: String,
+        coroutineSupport: CoroutineSupport,
+        platformKind: TargetPlatformKind<*>?, // if null, detect by module dependencies
+        modelsProvider: IdeModifiableModelsProvider
+) {
     val module = module
     with(configuration.settings) {
-        versionInfo.targetPlatformKind = null
+        versionInfo.targetPlatformKind = platformKind
         versionInfo.apiLevel = null
         initializeIfNeeded(module, modelsProvider.getModifiableRootModel(module))
         with(versionInfo) {