Add support for Kotlin top-level functions

Author: volivan239

utbot-core/src/main/kotlin/org/utbot/common/KClassUtil.kt

@@ -14,3 +14,6 @@ fun Method.invokeCatching(obj: Any?, args: List<Any?>) = try {
 
 val KClass<*>.allNestedClasses: List<KClass<*>>
     get() = listOf(this) + nestedClasses.flatMap { it.allNestedClasses }
+
+val Class<*>.allNestedClasses: List<Class<*>>
+    get() = listOf(this) + this.declaredClasses.flatMap { it.declaredClasses.toList() }

utbot-framework/src/main/kotlin/org/utbot/framework/process/EngineMain.kt

@@ -21,6 +21,7 @@ import org.utbot.framework.plugin.api.util.UtContext
 import org.utbot.framework.plugin.api.util.executableId
 import org.utbot.framework.plugin.api.util.id
 import org.utbot.framework.plugin.api.util.jClass
+import org.utbot.framework.plugin.api.util.method
 import org.utbot.framework.plugin.services.JdkInfo
 import org.utbot.framework.process.generated.*
 import org.utbot.framework.util.ConflictTriggers
@@ -36,7 +37,7 @@ import org.utbot.summary.summarize
 import java.io.File
 import java.net.URLClassLoader
 import java.nio.file.Paths
-import kotlin.reflect.full.functions
+import kotlin.reflect.jvm.kotlinFunction
 import kotlin.time.Duration.Companion.seconds
 
 private val messageFromMainTimeoutMillis = 120.seconds
@@ -158,8 +159,8 @@ private fun EngineProcessModel.setup(
     synchronizer.measureExecutionForTermination(findMethodsInClassMatchingSelected) { params ->
         val classId = kryoHelper.readObject<ClassId>(params.classId)
         val selectedSignatures = params.signatures.map { Signature(it.name, it.parametersTypes) }
-        FindMethodsInClassMatchingSelectedResult(kryoHelper.writeObject(classId.jClass.kotlin.allNestedClasses.flatMap { clazz ->
-            clazz.functions.sortedWith(compareBy { selectedSignatures.indexOf(it.signature()) })
+        FindMethodsInClassMatchingSelectedResult(kryoHelper.writeObject(classId.jClass.allNestedClasses.flatMap { clazz ->
+            clazz.id.allMethods.mapNotNull { it.method.kotlinFunction }.sortedWith(compareBy { selectedSignatures.indexOf(it.signature()) })
                 .filter { it.signature().normalized() in selectedSignatures }
                 .map { it.executableId }
         }))
@@ -168,7 +169,7 @@ private fun EngineProcessModel.setup(
         val classId = kryoHelper.readObject<ClassId>(params.classId)
         val bySignature = kryoHelper.readObject<Map<Signature, List<String>>>(params.bySignature)
         FindMethodParamNamesResult(kryoHelper.writeObject(
-            classId.jClass.kotlin.allNestedClasses.flatMap { it.functions }
+            classId.jClass.allNestedClasses.flatMap { clazz -> clazz.id.allMethods.mapNotNull { it.method.kotlinFunction } }
                 .mapNotNull { method -> bySignature[method.signature()]?.let { params -> method.executableId to params } }
                 .toMap()
         ))

utbot-intellij/src/main/kotlin/org/utbot/intellij/plugin/ui/actions/GenerateTestsAction.kt

@@ -16,8 +16,10 @@ import com.intellij.openapi.roots.ModuleRootManager
 import com.intellij.openapi.roots.ProjectFileIndex
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.psi.*
+import com.intellij.psi.impl.PsiJavaParserFacadeImpl
 import com.intellij.psi.util.PsiTreeUtil
 import com.intellij.refactoring.util.classMembers.MemberInfo
+import org.jetbrains.kotlin.asJava.findFacadeClass
 import org.jetbrains.kotlin.idea.core.getPackage
 import org.jetbrains.kotlin.idea.core.util.toPsiDirectory
 import org.jetbrains.kotlin.idea.core.util.toPsiFile
@@ -26,6 +28,7 @@ import org.utbot.intellij.plugin.util.extractFirstLevelMembers
 import org.utbot.intellij.plugin.util.isVisible
 import java.util.*
 import org.jetbrains.kotlin.j2k.getContainingClass
+import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.utils.addIfNotNull
 import org.utbot.framework.plugin.api.util.LockFile
 import org.utbot.intellij.plugin.models.packageName
@@ -60,11 +63,13 @@ class GenerateTestsAction : AnAction(), UpdateInBackground {
         if (editor != null) {
             //The action is being called from editor
             val file = e.getData(CommonDataKeys.PSI_FILE) ?: return null
+            //file.setName("abcdef")
             val element = findPsiElement(file, editor) ?: return null
 
             val psiElementHandler = PsiElementHandler.makePsiElementHandler(file)
 
-            if (psiElementHandler.isCreateTestActionAvailable(element)) {
+            // When in Kotlin file, we should propose top-level functions for testing
+            if (psiElementHandler.isCreateTestActionAvailable(element) || file is KtFile) {
                 val srcClass = psiElementHandler.containingClass(element) ?: return null
                 val srcSourceRoot = srcClass.getSourceRoot() ?: return null
                 val srcMembers = srcClass.extractFirstLevelMembers(false)
@@ -232,6 +237,7 @@ class GenerateTestsAction : AnAction(), UpdateInBackground {
             return emptySet()
         }
         val allClasses = psiFiles.flatMap { getClassesFromFile(it) }.toMutableSet()
+        allClasses.addAll(psiFiles.mapNotNull { (it as? KtFile)?.findFacadeClass() })
         for (psiDir in psiDirectories) allClasses += getAllClasses(psiDir)
 
         return allClasses

utbot-intellij/src/main/kotlin/org/utbot/intellij/plugin/ui/utils/KotlinPsiElementHandler.kt

@@ -2,13 +2,16 @@ package org.utbot.intellij.plugin.ui.utils
 
 import com.intellij.psi.PsiClass
 import com.intellij.psi.PsiElement
+import com.intellij.psi.util.findParentOfType
+import org.jetbrains.kotlin.asJava.findFacadeClass
 import org.jetbrains.kotlin.idea.testIntegration.KotlinCreateTestIntention
 import org.jetbrains.kotlin.psi.KtClass
 import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi.KtNamedDeclaration
 import org.jetbrains.kotlin.psi.KtNamedFunction
 import org.jetbrains.kotlin.psi.psiUtil.parentsWithSelf
+import org.jetbrains.kotlin.toKtPsiSourceElement
 import org.jetbrains.uast.toUElement
 
 class KotlinPsiElementHandler(
@@ -31,6 +34,12 @@ class KotlinPsiElementHandler(
         element?.parentsWithSelf
             ?.firstOrNull { it is KtClassOrObject || it is KtNamedDeclaration && it.parent is KtFile } as? KtNamedDeclaration
 
-    override fun containingClass(element: PsiElement): PsiClass? =
-         element.parentsWithSelf.firstOrNull { it is KtClassOrObject }?.let { toPsi(it, PsiClass::class.java) }
+    override fun containingClass(element: PsiElement): PsiClass? {
+        element.findParentOfType<KtClassOrObject>(strict=false)?.let {
+            return toPsi(it, PsiClass::class.java)
+        }
+        return element.findParentOfType<KtFile>(strict=false)?.findFacadeClass()?.let {
+            toPsi(it, PsiClass::class.java)
+        }
+    }
 }