Cleanup: fix some compiler warnings (mostly deprecations, javaClass)

compiler/cli/src/org/jetbrains/kotlin/cli/common/output/outputUtils.kt

@@ -34,14 +34,14 @@ fun OutputFileCollection.writeAll(outputDir: File, report: (file: OutputFile, so
     }
 }
 
-private val REPORT_NOTHING = { file: OutputFile, sources: List<File>, output: File -> }
+private val REPORT_NOTHING: (OutputFile, List<File>, File) -> Unit = { _, _, _ -> }
 
 fun OutputFileCollection.writeAllTo(outputDir: File) {
     writeAll(outputDir, REPORT_NOTHING)
 }
 
 fun OutputFileCollection.writeAll(outputDir: File, messageCollector: MessageCollector) {
-    writeAll(outputDir) { file, sources, output ->
+    writeAll(outputDir) { _, sources, output ->
         messageCollector.report(CompilerMessageSeverity.OUTPUT, OutputMessageUtil.formatOutputMessage(sources, output), CompilerMessageLocation.NO_LOCATION)
     }
 }

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/PluginCliParser.kt

@@ -35,7 +35,7 @@ object PluginCliParser {
                         ?.map { File(it).toURI().toURL() }
                         ?.toTypedArray()
                         ?: arrayOf<URL>(),
-                javaClass.classLoader
+                this::class.java.classLoader
         )
 
         val componentRegistrars = ServiceLoader.load(ComponentRegistrar::class.java, classLoader).toMutableList()

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/CliLightClassGenerationSupport.kt

@@ -44,7 +44,6 @@ import org.jetbrains.kotlin.resolve.scopes.DescriptorKindFilter
 import org.jetbrains.kotlin.resolve.scopes.MemberScope
 import org.jetbrains.kotlin.util.slicedMap.ReadOnlySlice
 import org.jetbrains.kotlin.util.slicedMap.WritableSlice
-import org.jetbrains.kotlin.utils.emptyOrSingletonList
 import kotlin.properties.Delegates
 
 /**
@@ -147,7 +146,7 @@ class CliLightClassGenerationSupport(project: Project) : LightClassGenerationSup
         val filesForFacade = findFilesForFacade(facadeFqName, scope)
         if (filesForFacade.isEmpty()) return emptyList()
 
-        return emptyOrSingletonList<PsiClass>(
+        return listOfNotNull<PsiClass>(
                 KtLightClassForFacade.createForFacade(psiManager, facadeFqName, scope, filesForFacade))
     }
 

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/CliVirtualFileFinder.kt

@@ -26,7 +26,6 @@ import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.serialization.deserialization.MetadataPackageFragment
-import org.jetbrains.kotlin.utils.addToStdlib.check
 import java.io.InputStream
 
 class CliVirtualFileFinder(
@@ -61,6 +60,6 @@ class CliVirtualFileFinder(
 
     private fun findBinaryClass(classId: ClassId, fileName: String): VirtualFile? =
             index.findClass(classId, acceptedRootTypes = JavaRoot.OnlyBinary) { dir, _ ->
-                dir.findChild(fileName)?.check(VirtualFile::isValid)
-            }?.check { it in scope }
+                dir.findChild(fileName)?.takeIf(VirtualFile::isValid)
+            }?.takeIf { it in scope }
 }

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCliJavaFileManagerImpl.kt

@@ -32,7 +32,6 @@ import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.resolve.jvm.KotlinCliJavaFileManager
 import org.jetbrains.kotlin.util.PerformanceCounter
-import org.jetbrains.kotlin.utils.addToStdlib.check
 import java.util.*
 import kotlin.properties.Delegates
 
@@ -50,7 +49,7 @@ class KotlinCliJavaFileManagerImpl(private val myPsiManager: PsiManager) : CoreJ
             val classNameWithInnerClasses = classId.relativeClassName.asString()
             index.findClass(classId) { dir, type ->
                 findClassGivenPackage(allScope, dir, classNameWithInnerClasses, type)
-            }?.check { it.containingFile.virtualFile in searchScope }
+            }?.takeIf { it.containingFile.virtualFile in searchScope }
         }
     }
 
@@ -88,7 +87,7 @@ class KotlinCliJavaFileManagerImpl(private val myPsiManager: PsiManager) : CoreJ
     override fun findPackage(packageName: String): PsiPackage? {
         var found = false
         val packageFqName = packageName.toSafeFqName() ?: return null
-        index.traverseDirectoriesInPackage(packageFqName) { dir, rootType ->
+        index.traverseDirectoriesInPackage(packageFqName) { _, _ ->
             found = true
             //abort on first found
             false
@@ -149,10 +148,7 @@ class KotlinCliJavaFileManagerImpl(private val myPsiManager: PsiManager) : CoreJ
             var curClass = topLevelClass
             while (segments.hasNext()) {
                 val innerClassName = segments.next()
-                val innerClass = curClass.findInnerClassByName(innerClassName, false)
-                if (innerClass == null) {
-                    return null
-                }
+                val innerClass = curClass.findInnerClassByName(innerClassName, false) ?: return null
                 curClass = innerClass
             }
             return curClass

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/index/JvmDependenciesIndexImpl.kt

@@ -93,7 +93,7 @@ class JvmDependenciesIndexImpl(_roots: List<JavaRoot>): JvmDependenciesIndex {
     ): Set<String> {
         val result = hashSetOf<String>()
         traverseDirectoriesInPackage(packageFqName, continueSearch = {
-            dir, rootType ->
+            dir, _ ->
 
             for (child in dir.children) {
                 if (child.extension != "class" && child.extension != "java") continue

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/repl/GenericReplCompiler.kt

@@ -73,7 +73,7 @@ open class GenericReplCompiler(disposable: Disposable,
             val scriptDescriptor = when (analysisResult) {
                 is ReplCodeAnalyzer.ReplLineAnalysisResult.WithErrors -> return ReplCompileResult.Error(errorHolder.renderedDiagnostics)
                 is ReplCodeAnalyzer.ReplLineAnalysisResult.Successful -> analysisResult.scriptDescriptor
-                else -> error("Unexpected result ${analysisResult.javaClass}")
+                else -> error("Unexpected result ${analysisResult::class.java}")
             }
 
             val generationState = GenerationState(

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/repl/ReplInterpreter.kt

@@ -103,7 +103,7 @@ class ReplInterpreter(
         val scriptDescriptor = when (analysisResult) {
             is ReplCodeAnalyzer.ReplLineAnalysisResult.WithErrors -> return LineResult.Error.CompileTime(errorHolder.renderedDiagnostics)
             is ReplCodeAnalyzer.ReplLineAnalysisResult.Successful -> analysisResult.scriptDescriptor
-            else -> error("Unexpected result ${analysisResult.javaClass}")
+            else -> error("Unexpected result ${analysisResult::class.java}")
         }
 
         val state = GenerationState(
@@ -185,7 +185,7 @@ class ReplInterpreter(
         private fun renderStackTrace(cause: Throwable, startFromMethodName: String): String {
             val newTrace = arrayListOf<StackTraceElement>()
             var skip = true
-            for ((_, element) in cause.stackTrace.withIndex().reversed()) {
+            for (element in cause.stackTrace.reversed()) {
                 if ("${element.className}.${element.methodName}" == startFromMethodName) {
                     skip = false
                 }