[K/JS] Introduce v2015 target

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/GradleOption.kt

@@ -33,6 +33,7 @@ annotation class GradleOption(
 enum class DefaultValue {
     BOOLEAN_FALSE_DEFAULT,
     BOOLEAN_TRUE_DEFAULT,
+    BOOLEAN_NULL_DEFAULT,
     STRING_NULL_DEFAULT,
     EMPTY_STRING_LIST_DEFAULT,
     EMPTY_STRING_ARRAY_DEFAULT,

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/K2JSCompilerArguments.kt

@@ -166,7 +166,7 @@ class K2JSCompilerArguments : CommonCompilerArguments() {
         gradleInputType = GradleInputTypes.INPUT,
         shouldGenerateDeprecatedKotlinOptions = true,
     )
-    @Argument(value = "-target", valueDescription = "{ v5 }", description = "Generate JS files for the specified ECMA version.")
+    @Argument(value = "-target", valueDescription = "{ es5, es2015 }", description = "Generate JS files for the specified ECMA version.")
     var target: String? = null
         set(value) {
             checkFrozen()
@@ -192,12 +192,12 @@ class K2JSCompilerArguments : CommonCompilerArguments() {
     @Argument(
             value = "-module-kind",
             valueDescription = "{plain|amd|commonjs|umd|es}",
-            description = "The kind of JS module generated by the compiler."
+            description = "The kind of JS module generated by the compiler. ES modules are enabled by default in case of ES2015 target usage"
     )
-    var moduleKind: String? = MODULE_PLAIN
+    var moduleKind: String? = null
         set(value) {
             checkFrozen()
-            field = if (value.isNullOrEmpty()) MODULE_PLAIN else value
+            field = value
         }
 
     @GradleOption(
@@ -460,15 +460,15 @@ In combination with '-meta-info', this generates both IR and pre-IR versions of
         }
 
     @GradleOption(
-        value = DefaultValue.BOOLEAN_FALSE_DEFAULT,
+        value = DefaultValue.BOOLEAN_NULL_DEFAULT,
         gradleInputType = GradleInputTypes.INPUT,
         shouldGenerateDeprecatedKotlinOptions = true,
     )
     @Argument(
         value = "-Xes-classes",
-        description = "Let generated JavaScript code use ES2015 classes."
+        description = "Let generated JavaScript code use ES2015 classes. Enabled by default in case of ES2015 target usage"
     )
-    var useEsClasses = false
+    var useEsClasses: Boolean? = null
         set(value) {
             checkFrozen()
             field = value
@@ -486,9 +486,9 @@ In combination with '-meta-info', this generates both IR and pre-IR versions of
 
     @Argument(
         value = "-Xes-generators",
-        description = "Enable ES2015 generator functions usage inside the compiled code"
+        description = "Enable ES2015 generator functions usage inside the compiled code. Enabled by default in case of ES2015 target usage"
     )
-    var useEsGenerators = false
+    var useEsGenerators: Boolean? = null
         set(value) {
             checkFrozen()
             field = value
@@ -657,7 +657,7 @@ In combination with '-meta-info', this generates both IR and pre-IR versions of
         collector.deprecationWarn(irBaseClassInMetadata, false, "-Xir-base-class-in-metadata")
         collector.deprecationWarn(irNewIr2Js, true, "-Xir-new-ir2js")
 
-        if (irPerFile && moduleKind != MODULE_ES) {
+        if (irPerFile && (moduleKind != MODULE_ES && target != ES_2015)) {
             collector.report(
                 CompilerMessageSeverity.ERROR,
                 "Per-file compilation can't be used with any `moduleKind` except `es` (ECMAScript Modules)"

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/K2JsArgumentConstants.java

@@ -26,6 +26,8 @@ public interface K2JsArgumentConstants {
     String MODULE_UMD = "umd";
     String MODULE_ES = "es";
 
+    String ES_2015 = "es2015";
+
     String GRANULARITY_WHOLE_PROGRAM = "whole-program";
     String GRANULARITY_PER_MODULE = "per-module";
     String GRANULARITY_PER_FILE = "per-file";

compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt

@@ -145,6 +145,15 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
     }
 
 
+    private val K2JSCompilerArguments.targetVersion: EcmaVersion?
+        get() {
+            val targetString = target
+            return when {
+                targetString != null -> EcmaVersion.entries.firstOrNull { it.name == targetString }
+                else -> EcmaVersion.defaultVersion()
+            }
+        }
+
     override fun doExecute(
         arguments: K2JSCompilerArguments,
         configuration: CompilerConfiguration,
@@ -153,6 +162,15 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
     ): ExitCode {
         val messageCollector = configuration.getNotNull(CLIConfigurationKeys.MESSAGE_COLLECTOR_KEY)
 
+        val targetVersion = arguments.targetVersion?.also {
+            configuration.put(JSConfigurationKeys.TARGET, it)
+        }
+
+        if (targetVersion == null) {
+            messageCollector.report(ERROR, "Unsupported ECMA version: ${arguments.target}")
+            return COMPILATION_ERROR
+        }
+
         val pluginLoadResult = loadPlugins(paths, arguments, configuration)
         if (pluginLoadResult != OK) return pluginLoadResult
 
@@ -182,7 +200,6 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
         configuration.put(JSConfigurationKeys.WASM_USE_TRAPS_INSTEAD_OF_EXCEPTIONS, arguments.wasmUseTrapsInsteadOfExceptions)
         configuration.putIfNotNull(JSConfigurationKeys.WASM_TARGET, arguments.wasmTarget?.let(WasmTarget::fromName))
 
-        configuration.put(JSConfigurationKeys.USE_ES6_CLASSES, arguments.useEsClasses)
         configuration.put(JSConfigurationKeys.OPTIMIZE_GENERATED_JS, arguments.optimizeGeneratedJs)
 
         val commonSourcesArray = arguments.commonSources
@@ -206,14 +223,21 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
         val projectJs = environmentForJS.project
         val configurationJs = environmentForJS.configuration
         val sourcesFiles = environmentForJS.getSourceFiles()
+        val isES2015 = targetVersion == EcmaVersion.es2015
+        val moduleKind = configuration[JSConfigurationKeys.MODULE_KIND]
+            ?: moduleKindMap[arguments.moduleKind]
+            ?: ModuleKind.ES.takeIf { isES2015 }
+            ?: ModuleKind.UMD
 
+        configurationJs.put(JSConfigurationKeys.MODULE_KIND, moduleKind)
         configurationJs.put(CLIConfigurationKeys.ALLOW_KOTLIN_PACKAGE, arguments.allowKotlinPackage)
         configurationJs.put(CLIConfigurationKeys.RENDER_DIAGNOSTIC_INTERNAL_NAME, arguments.renderInternalDiagnosticNames)
         configurationJs.put(JSConfigurationKeys.PROPERTY_LAZY_INITIALIZATION, arguments.irPropertyLazyInitialization)
         configurationJs.put(JSConfigurationKeys.GENERATE_POLYFILLS, arguments.generatePolyfills)
         configurationJs.put(JSConfigurationKeys.GENERATE_DTS, arguments.generateDts)
-        configurationJs.put(JSConfigurationKeys.COMPILE_SUSPEND_AS_JS_GENERATOR, arguments.useEsGenerators)
         configurationJs.put(JSConfigurationKeys.GENERATE_INLINE_ANONYMOUS_FUNCTIONS, arguments.irGenerateInlineAnonymousFunctions)
+        configurationJs.put(JSConfigurationKeys.USE_ES6_CLASSES, arguments.useEsClasses ?: isES2015)
+        configurationJs.put(JSConfigurationKeys.COMPILE_SUSPEND_AS_JS_GENERATOR, arguments.useEsGenerators ?: isES2015)
 
         arguments.platformArgumentsProviderJsExpression?.let {
             configurationJs.put(JSConfigurationKeys.DEFINE_PLATFORM_MAIN_FUNCTION_ARGUMENTS, it)
@@ -294,8 +318,6 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
         }
 
         if (arguments.irProduceJs) {
-            val moduleKind = configurationJs[JSConfigurationKeys.MODULE_KIND] ?: error("cannot get 'module kind' from configuration")
-
             messageCollector.report(INFO, "Produce executable: $outputDirPath")
             messageCollector.report(INFO, "Cache directory: ${arguments.cacheDirectory}")
 
@@ -686,11 +708,6 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
     ) {
         val messageCollector = configuration.getNotNull(CLIConfigurationKeys.MESSAGE_COLLECTOR_KEY)
 
-        if (arguments.target != null) {
-            assert("v5" == arguments.target) { "Unsupported ECMA version: " + arguments.target!! }
-        }
-        configuration.put(JSConfigurationKeys.TARGET, EcmaVersion.defaultVersion())
-
         if (arguments.sourceMap) {
             configuration.put(JSConfigurationKeys.SOURCE_MAP, true)
             if (arguments.sourceMapPrefix != null) {
@@ -733,19 +750,10 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
             configuration.put(JSConfigurationKeys.FRIEND_PATHS, friendPaths)
         }
 
-        val moduleKindName = arguments.moduleKind
-        var moduleKind: ModuleKind? = if (moduleKindName != null) moduleKindMap[moduleKindName] else ModuleKind.PLAIN
-        if (moduleKind == null) {
-            messageCollector.report(
-                ERROR, "Unknown module kind: $moduleKindName. Valid values are: plain, amd, commonjs, umd, es", null
-            )
-            moduleKind = ModuleKind.PLAIN
-        }
         if (arguments.wasm) {
             // K/Wasm support ES modules only.
-            moduleKind = ModuleKind.ES
+            configuration.put(JSConfigurationKeys.MODULE_KIND, ModuleKind.ES)
         }
-        configuration.put(JSConfigurationKeys.MODULE_KIND, moduleKind)
 
         configuration.putIfNotNull(JSConfigurationKeys.INCREMENTAL_DATA_PROVIDER, services[IncrementalDataProvider::class.java])
         configuration.putIfNotNull(JSConfigurationKeys.INCREMENTAL_RESULTS_CONSUMER, services[IncrementalResultsConsumer::class.java])

compiler/testData/cli/js/jsExtraHelp.out

@@ -50,8 +50,8 @@ where advanced options include:
                              JS expression that will be executed in runtime and be put as an Array<String> parameter of the main function
   -Xstrict-implicit-export-types Generate strict types for implicitly exported entities inside d.ts files. This is available in the IR backend only.
   -Xtyped-arrays             Translate primitive arrays into JS typed arrays.
-  -Xes-classes               Let generated JavaScript code use ES2015 classes.
+  -Xes-classes               Let generated JavaScript code use ES2015 classes. Enabled by default in case of ES2015 target usage
-  -Xes-generators            Enable ES2015 generator functions usage inside the compiled code
+  -Xes-generators            Enable ES2015 generator functions usage inside the compiled code. Enabled by default in case of ES2015 target usage
   -Xwasm                     Use the experimental WebAssembly compiler backend.
   -Xwasm-debug-info          Add debug info to the compiled WebAssembly module.
   -Xwasm-enable-array-range-checks

compiler/testData/cli/js/jsHelp.out

@@ -4,7 +4,7 @@ where possible options include:
   -main {call|noCall}        Specify whether the 'main' function should be called upon execution.
   -meta-info                 Generate .meta.js and .kjsm files with metadata. Use this to create a library.
   -module-kind {plain|amd|commonjs|umd|es}
-                             The kind of JS module generated by the compiler.
+                             The kind of JS module generated by the compiler. ES modules are enabled by default in case of ES2015 target usage
   -ir-output-name            Base name of generated files.
   -no-stdlib                 Don't automatically include the default Kotlin/JS stdlib in compilation dependencies.
   -ir-output-dir <directory> Destination for generated files.
@@ -16,7 +16,7 @@ where possible options include:
   -source-map-names-policy {no|simple-names|fully-qualified-names}
                              Mode for mapping generated names to original names (IR backend only).
   -source-map-prefix         Add the specified prefix to the paths in the source map.
-  -target { v5 }             Generate JS files for the specified ECMA version.
+  -target { es5, es2015 }    Generate JS files for the specified ECMA version.
   -Werror                    Report an error if there are any warnings.
   -api-version <version>     Allow using declarations from only the specified version of bundled libraries.
   -X                         Print a synopsis of advanced options.

compiler/tests-common-new/tests/org/jetbrains/kotlin/test/services/configuration/JsEnvironmentConfigurator.kt

@@ -217,7 +217,7 @@ class JsEnvironmentConfigurator(testServices: TestServices) : EnvironmentConfigu
         configuration.put(JSConfigurationKeys.FRIEND_PATHS, friends)
 
         configuration.put(CommonConfigurationKeys.MODULE_NAME, module.name.removeSuffix(OLD_MODULE_SUFFIX))
-        configuration.put(JSConfigurationKeys.TARGET, EcmaVersion.v5)
+        configuration.put(JSConfigurationKeys.TARGET, EcmaVersion.es5)
 
         val errorIgnorancePolicy = registeredDirectives[ERROR_POLICY].singleOrNull() ?: ErrorTolerancePolicy.DEFAULT
         configuration.put(JSConfigurationKeys.ERROR_TOLERANCE_POLICY, errorIgnorancePolicy)

generators/tests/org/jetbrains/kotlin/generators/arguments/DefaultValues.kt

@@ -35,6 +35,8 @@ open class DefaultValues(
 
     object BooleanTrueDefault : DefaultBoolean(true)
 
+    object BooleanNullDefault : DefaultValues("null", typeOf<Boolean?>(), typeOf<Boolean?>())
+
     object StringNullDefault : DefaultValues("null", typeOf<String?>(), typeOf<String?>())
 
     object EmptyStringListDefault : DefaultValues("emptyList<String>()", typeOf<List<String>>(), typeOf<List<String>>())
@@ -91,22 +93,22 @@ open class DefaultValues(
     )
 
     object JsEcmaVersions : DefaultValues(
-        "\"v5\"",
+        "\"es5\"",
         typeOf<String>(),
         typeOf<String>(),
-        possibleValues = listOf("\"v5\"")
+        possibleValues = listOf("\"es5\"", "\"es2015\"")
     )
 
     object JsModuleKinds : DefaultValues(
-        "${typeOf<JsModuleKind>()}.${JsModuleKind.MODULE_PLAIN.name}",
+        "null",
-        typeOf<JsModuleKind>(),
+        typeOf<JsModuleKind?>(),
-        typeOf<String>(),
+        typeOf<String?>(),
         possibleValues = listOf("\"plain\"", "\"amd\"", "\"commonjs\"", "\"umd\""),
         fromKotlinOptionConverterProp = """
-        ${typeOf<JsModuleKind>()}.fromKind(this)
+        this?.let { ${typeOf<JsModuleKind>()}.fromKind(it) }
         """.trimIndent(),
         toKotlinOptionConverterProp = """
-        this.kind
+        this?.kind
         """.trimIndent()
     )
 

generators/tests/org/jetbrains/kotlin/generators/arguments/GenerateGradleOptions.kt

@@ -952,6 +952,7 @@ private val KProperty1<*, *>.gradleValues: DefaultValues
         when (this) {
             DefaultValue.BOOLEAN_FALSE_DEFAULT -> DefaultValues.BooleanFalseDefault
             DefaultValue.BOOLEAN_TRUE_DEFAULT -> DefaultValues.BooleanTrueDefault
+            DefaultValue.BOOLEAN_NULL_DEFAULT -> DefaultValues.BooleanNullDefault
             DefaultValue.STRING_NULL_DEFAULT -> DefaultValues.StringNullDefault
             DefaultValue.EMPTY_STRING_LIST_DEFAULT -> DefaultValues.EmptyStringListDefault
             DefaultValue.EMPTY_STRING_ARRAY_DEFAULT -> DefaultValues.EmptyStringArrayDefault

js/js.frontend/src/org/jetbrains/kotlin/js/config/EcmaVersion.java

@@ -19,10 +19,10 @@ package org.jetbrains.kotlin.js.config;
 import org.jetbrains.annotations.NotNull;
 
 public enum EcmaVersion {
-    v3, v5;
+    es5, es2015;
 
     @NotNull
     public static EcmaVersion defaultVersion() {
-        return v5;
+        return es5;
     }
 }

js/js.tests/test/org/jetbrains/kotlin/js/testOld/utils/JsTestUtils.java

@@ -36,7 +36,7 @@ public final class JsTestUtils {
 
     @NotNull
     public static EnumSet<EcmaVersion> successOnEcmaV5() {
-        return EnumSet.of(EcmaVersion.v5);
+        return EnumSet.of(EcmaVersion.es5);
     }
 
     @NotNull

libraries/tools/kotlin-gradle-plugin-api/api/kotlin-gradle-plugin-api.api

@@ -336,7 +336,7 @@ public abstract interface class org/jetbrains/kotlin/gradle/dsl/KotlinJsOptions
 	public abstract fun getSourceMapPrefix ()Ljava/lang/String;
 	public abstract fun getTarget ()Ljava/lang/String;
 	public abstract fun getTypedArrays ()Z
-	public abstract fun getUseEsClasses ()Z
+	public abstract fun getUseEsClasses ()Ljava/lang/Boolean;
 	public abstract fun setFriendModulesDisabled (Z)V
 	public abstract fun setMain (Ljava/lang/String;)V
 	public abstract fun setMetaInfo (Z)V
@@ -349,7 +349,7 @@ public abstract interface class org/jetbrains/kotlin/gradle/dsl/KotlinJsOptions
 	public abstract fun setSourceMapPrefix (Ljava/lang/String;)V
 	public abstract fun setTarget (Ljava/lang/String;)V
 	public abstract fun setTypedArrays (Z)V
-	public abstract fun setUseEsClasses (Z)V
+	public abstract fun setUseEsClasses (Ljava/lang/Boolean;)V
 }
 
 public final class org/jetbrains/kotlin/gradle/dsl/KotlinJsOptions$DefaultImpls {
@@ -370,7 +370,7 @@ public final class org/jetbrains/kotlin/gradle/dsl/KotlinJsOptions$DefaultImpls
 	public static fun getSuppressWarnings (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Z
 	public static fun getTarget (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Ljava/lang/String;
 	public static fun getTypedArrays (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Z
-	public static fun getUseEsClasses (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Z
+	public static fun getUseEsClasses (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Ljava/lang/Boolean;
 	public static fun getUseK2 (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Z
 	public static fun getVerbose (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;)Z
 	public static fun setAllWarningsAsErrors (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Z)V
@@ -390,7 +390,7 @@ public final class org/jetbrains/kotlin/gradle/dsl/KotlinJsOptions$DefaultImpls
 	public static fun setSuppressWarnings (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Z)V
 	public static fun setTarget (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Ljava/lang/String;)V
 	public static fun setTypedArrays (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Z)V
-	public static fun setUseEsClasses (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Z)V
+	public static fun setUseEsClasses (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Ljava/lang/Boolean;)V
 	public static fun setUseK2 (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Z)V
 	public static fun setVerbose (Lorg/jetbrains/kotlin/gradle/dsl/KotlinJsOptions;Z)V
 }

libraries/tools/kotlin-gradle-plugin-api/src/common/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJsCompilerOptions.kt

@@ -38,12 +38,13 @@ interface KotlinJsCompilerOptions : org.jetbrains.kotlin.gradle.dsl.KotlinCommon
     val metaInfo: org.gradle.api.provider.Property<kotlin.Boolean>
 
     /**
-     * The kind of JS module generated by the compiler.
+     * The kind of JS module generated by the compiler. ES modules are enabled by default in case of ES2015 target usage
      *
      * Possible values: "plain", "amd", "commonjs", "umd"
      *
-     * Default value: JsModuleKind.MODULE_PLAIN
+     * Default value: null
      */
+    @get:org.gradle.api.tasks.Optional
     @get:org.gradle.api.tasks.Input
     val moduleKind: org.gradle.api.provider.Property<org.jetbrains.kotlin.gradle.dsl.JsModuleKind>
 
@@ -107,9 +108,9 @@ interface KotlinJsCompilerOptions : org.jetbrains.kotlin.gradle.dsl.KotlinCommon
     /**
      * Generate JS files for the specified ECMA version.
      *
-     * Possible values: "v5"
+     * Possible values: "es5", "es2015"
      *
-     * Default value: "v5"
+     * Default value: "es5"
      */
     @get:org.gradle.api.tasks.Input
     val target: org.gradle.api.provider.Property<kotlin.String>
@@ -123,10 +124,11 @@ interface KotlinJsCompilerOptions : org.jetbrains.kotlin.gradle.dsl.KotlinCommon
     val typedArrays: org.gradle.api.provider.Property<kotlin.Boolean>
 
     /**
-     * Let generated JavaScript code use ES2015 classes.
+     * Let generated JavaScript code use ES2015 classes. Enabled by default in case of ES2015 target usage
      *
-     * Default value: false
+     * Default value: null
      */
+    @get:org.gradle.api.tasks.Optional
     @get:org.gradle.api.tasks.Input
     val useEsClasses: org.gradle.api.provider.Property<kotlin.Boolean>
 }

libraries/tools/kotlin-gradle-plugin-api/src/common/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJsOptions.kt

@@ -51,19 +51,19 @@ interface KotlinJsOptions : org.jetbrains.kotlin.gradle.dsl.KotlinCommonOptions
         get() = options.metaInfo.get()
         set(value) = options.metaInfo.set(value)
 
-    private val kotlin.String.moduleKindCompilerOption get() = org.jetbrains.kotlin.gradle.dsl.JsModuleKind.fromKind(this)
+    private val kotlin.String?.moduleKindCompilerOption get() = this?.let { org.jetbrains.kotlin.gradle.dsl.JsModuleKind.fromKind(it) }
 
-    private val org.jetbrains.kotlin.gradle.dsl.JsModuleKind.moduleKindKotlinOption get() = this.kind
+    private val org.jetbrains.kotlin.gradle.dsl.JsModuleKind?.moduleKindKotlinOption get() = this?.kind
 
     /**
-     * The kind of JS module generated by the compiler.
+     * The kind of JS module generated by the compiler. ES modules are enabled by default in case of ES2015 target usage
      *
      * Possible values: "plain", "amd", "commonjs", "umd"
      *
-     * Default value: JsModuleKind.MODULE_PLAIN
+     * Default value: null
      */
-    var moduleKind: kotlin.String
+    var moduleKind: kotlin.String?
-        get() = options.moduleKind.get().moduleKindKotlinOption
+        get() = options.moduleKind.orNull.moduleKindKotlinOption
         set(value) = options.moduleKind.set(value.moduleKindCompilerOption)
 
     /**
@@ -136,9 +136,9 @@ interface KotlinJsOptions : org.jetbrains.kotlin.gradle.dsl.KotlinCommonOptions
     /**
      * Generate JS files for the specified ECMA version.
      *
-     * Possible values: "v5"
+     * Possible values: "es5", "es2015"
      *
-     * Default value: "v5"
+     * Default value: "es5"
      */
     var target: kotlin.String
         get() = options.target.get()
@@ -154,11 +154,11 @@ interface KotlinJsOptions : org.jetbrains.kotlin.gradle.dsl.KotlinCommonOptions
         set(value) = options.typedArrays.set(value)
 
     /**
-     * Let generated JavaScript code use ES2015 classes.
+     * Let generated JavaScript code use ES2015 classes. Enabled by default in case of ES2015 target usage
      *
-     * Default value: false
+     * Default value: null
      */
-    var useEsClasses: kotlin.Boolean
+    var useEsClasses: kotlin.Boolean?
-        get() = options.useEsClasses.get()
+        get() = options.useEsClasses.orNull
         set(value) = options.useEsClasses.set(value)
 }

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJsCompilerOptionsDefault.kt

@@ -20,7 +20,7 @@ internal abstract class KotlinJsCompilerOptionsDefault @javax.inject.Inject cons
         objectFactory.property(kotlin.Boolean::class.java).convention(true)
 
     override val moduleKind: org.gradle.api.provider.Property<org.jetbrains.kotlin.gradle.dsl.JsModuleKind> =
-        objectFactory.property(org.jetbrains.kotlin.gradle.dsl.JsModuleKind::class.java).convention(org.jetbrains.kotlin.gradle.dsl.JsModuleKind.MODULE_PLAIN)
+        objectFactory.property(org.jetbrains.kotlin.gradle.dsl.JsModuleKind::class.java)
 
     override val moduleName: org.gradle.api.provider.Property<kotlin.String> =
         objectFactory.property(kotlin.String::class.java)
@@ -42,11 +42,11 @@ internal abstract class KotlinJsCompilerOptionsDefault @javax.inject.Inject cons
         objectFactory.property(kotlin.String::class.java)
 
     override val target: org.gradle.api.provider.Property<kotlin.String> =
-        objectFactory.property(kotlin.String::class.java).convention("v5")
+        objectFactory.property(kotlin.String::class.java).convention("es5")
 
     override val typedArrays: org.gradle.api.provider.Property<kotlin.Boolean> =
         objectFactory.property(kotlin.Boolean::class.java).convention(true)
 
     override val useEsClasses: org.gradle.api.provider.Property<kotlin.Boolean> =
-        objectFactory.property(kotlin.Boolean::class.java).convention(false)
+        objectFactory.property(kotlin.Boolean::class.java)
 }

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJsCompilerOptionsHelper.kt

@@ -15,7 +15,7 @@ internal object KotlinJsCompilerOptionsHelper {
         args.friendModulesDisabled = from.friendModulesDisabled.get()
         args.main = from.main.get().mode
         args.metaInfo = from.metaInfo.get()
-        args.moduleKind = from.moduleKind.get().kind
+        args.moduleKind = from.moduleKind.orNull?.kind
         args.moduleName = from.moduleName.orNull
         args.noStdlib = from.noStdlib.get()
         args.sourceMap = from.sourceMap.get()
@@ -24,7 +24,7 @@ internal object KotlinJsCompilerOptionsHelper {
         args.sourceMapPrefix = from.sourceMapPrefix.orNull
         args.target = from.target.get()
         args.typedArrays = from.typedArrays.get()
-        args.useEsClasses = from.useEsClasses.get()
+        args.useEsClasses = from.useEsClasses.orNull
     }
 
     internal fun syncOptionsAsConvention(

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/js/KotlinJsCompilation.kt

@@ -3,7 +3,7 @@
 * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
 */
 
-@file:Suppress("PackageDirectoryMismatch")
+@file:Suppress("PackageDirectoryMismatch", "DEPRECATION", "TYPEALIAS_EXPANSION_DEPRECATION")
 
 // Old package for compatibility
 package org.jetbrains.kotlin.gradle.plugin.mpp
@@ -13,8 +13,12 @@ import org.gradle.api.Action
 import org.gradle.api.attributes.AttributeContainer
 import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.TaskProvider
-import org.jetbrains.kotlin.gradle.dsl.*
+import org.jetbrains.kotlin.cli.common.arguments.K2JsArgumentConstants
-import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.dsl.JsModuleKind
+import org.jetbrains.kotlin.gradle.dsl.KotlinJsCompilerOptions
+import org.jetbrains.kotlin.gradle.dsl.KotlinJsOptions
+import org.jetbrains.kotlin.gradle.plugin.DeprecatedHasCompilerOptions
+import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType
 import org.jetbrains.kotlin.gradle.plugin.mpp.compilationImpl.KotlinCompilationImpl
 import org.jetbrains.kotlin.gradle.targets.js.dsl.KotlinJsSubTargetContainerDsl
 import org.jetbrains.kotlin.gradle.targets.js.ir.JsBinary
@@ -23,7 +27,6 @@ import org.jetbrains.kotlin.gradle.targets.js.npm.PackageJson
 import org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile
 import javax.inject.Inject
 
-@Suppress("TYPEALIAS_EXPANSION_DEPRECATION", "DEPRECATION")
 open class KotlinJsCompilation @Inject internal constructor(
     compilation: KotlinCompilationImpl,
 ) : DeprecatedAbstractKotlinCompilationToRunnableFiles<KotlinJsOptions>(compilation),
@@ -102,11 +105,19 @@ val KotlinJsCompilation.fileExtension: Provider<String>
     get() {
         val isWasm = platformType == KotlinPlatformType.wasm
         @Suppress("DEPRECATION")
-        return compilerOptions.options.moduleKind.map { moduleKind ->
+        return compilerOptions.options.moduleKind
-            if (isWasm || moduleKind == JsModuleKind.MODULE_ES) {
+            .orElse(
-                "mjs"
+                compilerOptions.options.target.map {
-            } else {
+                    if (it == K2JsArgumentConstants.ES_2015) {
-                "js"
+                        JsModuleKind.MODULE_ES
+                    } else JsModuleKind.MODULE_UMD
+                }
+            )
+            .map { moduleKind ->
+                if (isWasm || moduleKind == JsModuleKind.MODULE_ES) {
+                    "mjs"
+                } else {
+                    "js"
+                }
             }
-        }
     }

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/js/ir/KotlinBrowserJsIr.kt

@@ -13,6 +13,7 @@ import org.gradle.api.provider.Property
 import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.Copy
 import org.gradle.language.base.plugins.LifecycleBasePlugin
+import org.jetbrains.kotlin.cli.common.arguments.K2JsArgumentConstants.ES_2015
 import org.jetbrains.kotlin.gradle.dsl.JsModuleKind
 import org.jetbrains.kotlin.gradle.dsl.KotlinJsDce
 import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType
@@ -34,6 +35,7 @@ import org.jetbrains.kotlin.gradle.utils.doNotTrackStateCompat
 import org.jetbrains.kotlin.gradle.utils.domainObjectSet
 import org.jetbrains.kotlin.gradle.utils.relativeOrAbsolute
 import org.jetbrains.kotlin.util.capitalizeDecapitalize.toLowerCaseAsciiOnly
+import org.jetbrains.kotlin.utils.addToStdlib.runIf
 import javax.inject.Inject
 
 abstract class KotlinBrowserJsIr @Inject constructor(target: KotlinJsIrTarget) :
@@ -274,7 +276,11 @@ abstract class KotlinBrowserJsIr @Inject constructor(target: KotlinJsIrTarget) :
         this.inputFilesDirectory.set(inputFilesDirectory)
 
         val platformType = binary.compilation.platformType
-        val moduleKind = binary.linkTask.flatMap { it.compilerOptions.moduleKind }
+        val moduleKind = binary.linkTask.flatMap { task ->
+            task.compilerOptions.moduleKind.orElse(task.compilerOptions.target.map {
+                if (it == ES_2015) JsModuleKind.MODULE_ES else JsModuleKind.MODULE_UMD
+            })
+        }
 
         this.entryModuleName.set(entryModuleName)
         this.esModules.convention(

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/js/ir/KotlinJsIrTargetConfigurator.kt

@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.gradle.targets.js.ir
 
-import org.jetbrains.kotlin.gradle.dsl.JsModuleKind
 import org.jetbrains.kotlin.gradle.dsl.JsSourceMapEmbedMode
 import org.jetbrains.kotlin.gradle.dsl.KotlinJsCompilerOptions
 import org.jetbrains.kotlin.gradle.plugin.KotlinOnlyTargetConfigurator
@@ -15,7 +14,6 @@ open class KotlinJsIrTargetConfigurator :
 
     internal companion object {
         internal fun KotlinJsCompilerOptions.configureJsDefaultOptions() {
-            moduleKind.convention(JsModuleKind.MODULE_UMD)
             sourceMap.convention(true)
             sourceMapEmbedSources.convention(JsSourceMapEmbedMode.SOURCE_MAP_SOURCE_CONTENT_NEVER)
         }