Support running main() under JVM in multiplatform projects

#KT-20093 In progress

idea/idea-gradle/src/org/jetbrains/kotlin/idea/run/MultiplatformGradleProjectTaskRunner.kt

@@ -21,6 +21,7 @@ import com.intellij.openapi.externalSystem.ExternalSystemModulePropertyManager
 import com.intellij.openapi.externalSystem.model.project.ExternalSystemSourceType
 import com.intellij.openapi.externalSystem.util.ExternalSystemApiUtil
 import com.intellij.openapi.module.Module
+import com.intellij.openapi.roots.ModuleOrderEntry
 import com.intellij.openapi.roots.ModuleRootModel
 import com.intellij.openapi.roots.OrderEnumerationHandler
 import com.intellij.openapi.roots.OrderRootType
@@ -30,6 +31,7 @@ import com.intellij.task.ModuleBuildTask
 import com.intellij.task.ProjectTask
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.idea.project.languageVersionSettings
+import org.jetbrains.kotlin.idea.util.rootManager
 import org.jetbrains.plugins.gradle.execution.build.GradleProjectTaskRunner
 import org.jetbrains.plugins.gradle.model.ExternalSourceDirectorySet
 import org.jetbrains.plugins.gradle.service.project.data.ExternalProjectDataCache
@@ -84,6 +86,16 @@ class MultiplatformGradleOrderEnumeratorHandler : OrderEnumerationHandler() {
                 addOutputModuleRoots(sourceSet.sources[ExternalSystemSourceType.SOURCE], result)
             }
         }
+
+        val implModule = rootModel.module.findJvmImplementationModule()
+        implModule
+            ?.rootManager
+            ?.orderEntries()
+            ?.satisfying { orderEntry -> (orderEntry as? ModuleOrderEntry)?.module != rootModel.module }
+            ?.compileOnly()
+            ?.classesRoots
+            ?.mapTo(result) { it.url }
+
         return false
     }
 

idea/src/org/jetbrains/kotlin/idea/run/KotlinRunConfigurationProducer.kt

@@ -19,17 +19,21 @@ package org.jetbrains.kotlin.idea.run
 import com.intellij.execution.Location
 import com.intellij.execution.actions.ConfigurationContext
 import com.intellij.execution.actions.RunConfigurationProducer
+import com.intellij.openapi.module.Module
+import com.intellij.openapi.module.ModuleManager
 import com.intellij.openapi.project.DumbService
 import com.intellij.openapi.util.Ref
 import com.intellij.psi.PsiElement
 import com.intellij.psi.util.ClassUtil
 import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.asJava.toLightClass
+import org.jetbrains.kotlin.config.TargetPlatformKind
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.fileClasses.javaFileFacadeFqName
 import org.jetbrains.kotlin.idea.MainFunctionDetector
 import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
 import org.jetbrains.kotlin.idea.project.TargetPlatformDetector
+import org.jetbrains.kotlin.idea.project.targetPlatform
 import org.jetbrains.kotlin.idea.util.ProjectRootsUtil
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
@@ -58,8 +62,9 @@ class KotlinRunConfigurationProducer : RunConfigurationProducer<JetRunConfigurat
 
         val module = location.module ?: return null
 
-        if (TargetPlatformDetector.getPlatform(module) != JvmPlatform) return null
-
+        if (TargetPlatformDetector.getPlatform(module) !is JvmPlatform && module.findJvmImplementationModule() == null) {
+            return null
+        }
         val locationElement = location.psiElement
 
         return getEntryPointContainer(locationElement)
@@ -121,3 +126,9 @@ class KotlinRunConfigurationProducer : RunConfigurationProducer<JetRunConfigurat
 
     }
 }
+
+fun Module.findJvmImplementationModule(): Module? {
+    if (targetPlatform != TargetPlatformKind.Common) return null
+    val allDependentModules = ModuleManager.getInstance(project).getModuleDependentModules(this)
+    return allDependentModules.first { it.targetPlatform is TargetPlatformKind.Jvm }
+}