[JS] Support typeOf

compiler/ir/serialization.js/build.gradle.kts

@@ -126,6 +126,9 @@ val reducedRuntimeSources by task<Sync> {
                 "libraries/stdlib/js/src/kotlin/regexp.kt",
                 "libraries/stdlib/js/src/kotlin/sequence.kt",
                 "libraries/stdlib/js/src/kotlin/text/**",
+                "libraries/stdlib/js/src/kotlin/reflect/KTypeHelpers.kt",
+                "libraries/stdlib/js/src/kotlin/reflect/KTypeParameterImpl.kt",
+                "libraries/stdlib/js/src/kotlin/reflect/KTypeImpl.kt",
                 "libraries/stdlib/src/kotlin/collections/**",
                 "libraries/stdlib/src/kotlin/experimental/bitwiseOperations.kt",
                 "libraries/stdlib/src/kotlin/properties/Delegates.kt",

compiler/testData/codegen/box/reflection/typeOf/js/classes.kt

@@ -0,0 +1,42 @@
+// !USE_EXPERIMENTAL: kotlin.ExperimentalStdlibApi
+// TARGET_BACKEND: JS
+// IGNORE_BACKEND: JS_IR
+// WITH_REFLECT
+
+package test
+
+import kotlin.reflect.KType
+import kotlin.reflect.typeOf
+import kotlin.test.assertEquals
+
+class C
+
+fun check(expected: String, actual: KType) {
+    assertEquals(expected, actual.toString())
+}
+
+fun box(): String {
+    check("Any", typeOf<Any>())
+    check("String", typeOf<String>())
+    check("String?", typeOf<String?>())
+    check("Unit", typeOf<Unit>())
+
+    check("C", typeOf<C>())
+    check("C?", typeOf<C?>())
+
+    check("List<String>", typeOf<List<String>>())
+    check("Map<in Number, *>?", typeOf<Map<in Number, *>?>())
+    check("Enum<*>", typeOf<Enum<*>>())
+    check("Enum<AnnotationRetention>", typeOf<Enum<AnnotationRetention>>())
+
+    check("Array<Any>", typeOf<Array<Any>>())
+    check("Array<*>", typeOf<Array<*>>())
+    check("Array<IntArray>", typeOf<Array<IntArray>>())
+    check("Array<in Array<C>?>", typeOf<Array<in Array<C>?>>())
+
+    check("Int", typeOf<Int>())
+    check("Int?", typeOf<Int?>())
+    check("Boolean", typeOf<Boolean>())
+
+    return "OK"
+}

compiler/testData/codegen/box/reflection/typeOf/js/inlineClasses.kt

@@ -0,0 +1,33 @@
+// !USE_EXPERIMENTAL: kotlin.ExperimentalStdlibApi
+// TARGET_BACKEND: JS
+// IGNORE_BACKEND: JS_IR
+// WITH_REFLECT
+
+package test
+
+import kotlin.reflect.KType
+import kotlin.reflect.typeOf
+import kotlin.test.assertEquals
+
+inline class Z(val value: String)
+
+fun check(expected: String, actual: KType) {
+    assertEquals(expected, actual.toString())
+}
+
+fun box(): String {
+    check("Z", typeOf<Z>())
+    check("Z?", typeOf<Z?>())
+    check("Array<Z>", typeOf<Array<Z>>())
+    check("Array<Z?>", typeOf<Array<Z?>>())
+
+    check("UInt", typeOf<UInt>())
+    check("UInt?", typeOf<UInt?>())
+    check("ULong?", typeOf<ULong?>())
+    check("UShortArray", typeOf<UShortArray>())
+    check("UShortArray?", typeOf<UShortArray?>())
+    check("Array<UByteArray>", typeOf<Array<UByteArray>>())
+    check("Array<UByteArray?>?", typeOf<Array<UByteArray?>?>())
+
+    return "OK"
+}

compiler/testData/codegen/box/reflection/typeOf/js/kType.kt

@@ -0,0 +1,57 @@
+// !USE_EXPERIMENTAL: kotlin.ExperimentalStdlibApi
+// TARGET_BACKEND: JS
+// IGNORE_BACKEND: JS_IR
+// WITH_REFLECT
+
+import kotlin.test.*
+import kotlin.reflect.*
+
+inline fun <reified R> kType() = typeOf<R>()
+
+inline fun <reified R> kType(obj: R) = kType<R>()
+
+class C<T>
+class D
+
+fun <T> kTypeForCWithTypeParameter() = kType<C<T>>()
+
+class Outer<T> {
+    companion object Friend
+    inner class Inner<S>
+}
+
+object Object
+
+fun testBasics1() {
+    assertEquals("C<Int?>", kType<C<Int?>>().toString())
+    assertEquals("C<C<Any>>", kType<C<C<Any>>>().toString())
+
+    assertEquals("C<T>", kTypeForCWithTypeParameter<D>().toString())
+    assertEquals("Object", kType<Object>().toString())
+    assertEquals("Friend", kType<Outer.Friend>().toString())
+}
+
+fun testInner() {
+    val innerKType = kType<Outer<D>.Inner<String>>()
+    assertEquals(Outer.Inner::class, innerKType.classifier)
+    assertEquals(String::class, innerKType.arguments.first().type!!.classifier)
+    assertEquals(D::class, innerKType.arguments.last().type!!.classifier)
+}
+
+fun testAnonymousObject() {
+    val obj = object {}
+    val objType = kType(obj)
+
+    assertEquals("(non-denotable type)", objType.toString())
+    assertEquals(obj::class, objType.classifier)
+
+    assertTrue(objType.arguments.isEmpty())
+    assertFalse(objType.isMarkedNullable)
+}
+
+fun box(): String {
+    testBasics1()
+    testInner()
+    testAnonymousObject()
+    return "OK"
+}

compiler/testData/codegen/box/reflection/typeOf/js/manyTypeArguments.kt

@@ -0,0 +1,32 @@
+// !USE_EXPERIMENTAL: kotlin.ExperimentalStdlibApi
+// TARGET_BACKEND: JS
+// IGNORE_BACKEND: JS_IR
+// WITH_REFLECT
+
+package test
+
+import kotlin.reflect.typeOf
+import kotlin.test.assertEquals
+
+interface I1
+interface I2
+interface I3
+interface I4
+interface I5
+interface I6
+interface I7
+
+class C<T1, T2, T3, T4, T5, T6, T7>
+
+fun box(): String {
+    assertEquals(
+        "C<I1, I2, I3?, in I4, out I5, I6, I7?>",
+        typeOf<C<I1, I2, I3?, in I4, out I5, I6, I7?>>().toString()
+    )
+    assertEquals(
+        "C<out I1, I2?, I3, I4, I5, I6?, in I7>?",
+        typeOf<C<out I1, I2?, I3, I4, I5, I6?, in I7>?>().toString()
+    )
+
+    return "OK"
+}

compiler/testData/codegen/box/reflection/typeOf/js/multipleLayers.kt

@@ -0,0 +1,27 @@
+// !USE_EXPERIMENTAL: kotlin.ExperimentalStdlibApi
+// TARGET_BACKEND: JS
+// IGNORE_BACKEND: JS_IR
+// WITH_REFLECT
+
+package test
+
+import kotlin.reflect.typeOf
+import kotlin.reflect.KType
+import kotlin.test.assertEquals
+
+interface C
+
+inline fun <reified T> get() = typeOf<T>()
+
+inline fun <reified U> get1() = get<U?>()
+
+inline fun <reified V> get2(): KType {
+    return get1<Map<in V?, Array<V>>>()
+}
+
+fun box(): String {
+    assertEquals("C?", get1<C>().toString())
+    assertEquals("Map<in C?, Array<C>>?", get2<C>().toString())
+    assertEquals("Map<in List<C>?, Array<List<C>>>?", get2<List<C>>().toString())
+    return "OK"
+}

compiler/testData/codegen/box/reflection/typeOf/js/multipleModules.kt

@@ -0,0 +1,40 @@
+// !USE_EXPERIMENTAL: kotlin.ExperimentalStdlibApi
+// TARGET_BACKEND: JS
+// IGNORE_BACKEND: JS_IR
+// WITH_REFLECT
+
+// MODULE: lib1
+// FILE: lib1.kt
+import kotlin.reflect.typeOf
+
+inline fun <reified T> get() = typeOf<T>()
+
+// MODULE: lib2(lib1)
+// FILE: lib2.kt
+inline fun <reified U> get1() = get<U?>()
+
+// MODULE: lib3(lib1, lib2)
+// FILE: lib3.kt
+import kotlin.reflect.KType
+
+inline fun <reified V> get2(): KType {
+    return get1<Map<in V?, Array<V>>>()
+}
+
+// MODULE: main(lib1, lib2, lib3)
+// FILE: lib4.kt
+import kotlin.test.assertEquals
+
+interface C
+
+fun box(): String {
+    assertEquals("C?", get1<C>().toString())
+    assertEquals("Map<in C?, Array<C>>?", get2<C>().toString())
+    assertEquals("Map<in List<C>?, Array<List<C>>>?", get2<List<C>>().toString())
+
+    assertEquals("Short?", get1<Short>().toString())
+    assertEquals("Map<in Short?, Array<Short>>?", get2<Short>().toString())
+    assertEquals("Map<in List<Short>?, Array<List<Short>>>?", get2<List<Short>>().toString())
+
+    return "OK"
+}

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -22565,6 +22565,19 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/reflection/typeOf/multipleLayers.kt");
             }
 
+            @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/js")
+            @TestDataPath("$PROJECT_ROOT")
+            @RunWith(JUnit3RunnerWithInners.class)
+            public static class Js extends AbstractBlackBoxCodegenTest {
+                private void runTest(String testDataFilePath) throws Exception {
+                    KotlinTestUtils.runTest(this::doTest, TargetBackend.JVM, testDataFilePath);
+                }
+
+                public void testAllFilesPresentInJs() throws Exception {
+                    KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/typeOf/js"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM, true);
+                }
+            }
+
             @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/noReflect")
             @TestDataPath("$PROJECT_ROOT")
             @RunWith(JUnit3RunnerWithInners.class)

compiler/tests/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -22565,6 +22565,19 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/reflection/typeOf/multipleLayers.kt");
             }
 
+            @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/js")
+            @TestDataPath("$PROJECT_ROOT")
+            @RunWith(JUnit3RunnerWithInners.class)
+            public static class Js extends AbstractLightAnalysisModeTest {
+                private void runTest(String testDataFilePath) throws Exception {
+                    KotlinTestUtils.runTest(this::doTest, TargetBackend.JVM, testDataFilePath);
+                }
+
+                public void testAllFilesPresentInJs() throws Exception {
+                    KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/typeOf/js"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM, true);
+                }
+            }
+
             @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/noReflect")
             @TestDataPath("$PROJECT_ROOT")
             @RunWith(JUnit3RunnerWithInners.class)

compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -21455,6 +21455,19 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/reflection/typeOf/multipleLayers.kt");
             }
 
+            @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/js")
+            @TestDataPath("$PROJECT_ROOT")
+            @RunWith(JUnit3RunnerWithInners.class)
+            public static class Js extends AbstractIrBlackBoxCodegenTest {
+                private void runTest(String testDataFilePath) throws Exception {
+                    KotlinTestUtils.runTest(this::doTest, TargetBackend.JVM_IR, testDataFilePath);
+                }
+
+                public void testAllFilesPresentInJs() throws Exception {
+                    KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/typeOf/js"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM_IR, true);
+                }
+            }
+
             @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/noReflect")
             @TestDataPath("$PROJECT_ROOT")
             @RunWith(JUnit3RunnerWithInners.class)

js/js.ast/src/org/jetbrains/kotlin/js/backend/ast/metadata/metadataProperties.kt

@@ -129,6 +129,8 @@ var JsExpression.range: Pair<RangeType, RangeKind>? by MetadataProperty(default
 
 var JsExpression.primitiveKClass: JsExpression? by MetadataProperty(default = null)
 
+var JsExpression.kType: JsExpression? by MetadataProperty(default = null)
+
 data class CoroutineMetadata(
         val doResumeName: JsName,
         val stateName: JsName,
@@ -166,7 +168,8 @@ enum class SpecialFunction(val suggestedName: String) {
     COROUTINE_CONTROLLER("coroutineController"),
     COROUTINE_RECEIVER("coroutineReceiver"),
     SET_COROUTINE_RESULT("setCoroutineResult"),
-    GET_KCLASS("getKClass")
+    GET_KCLASS("getKClass"),
+    GET_REIFIED_TYPE_PARAMETER_KTYPE("getReifiedTypeParameterKType")
 }
 
 enum class BoxingKind {

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/diagnostics/JsReflectionAPICallChecker.kt

@@ -23,19 +23,27 @@ import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.NotFoundClasses
 import org.jetbrains.kotlin.diagnostics.Errors.UNSUPPORTED
+import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.calls.checkers.AbstractReflectionApiCallChecker
 import org.jetbrains.kotlin.resolve.calls.checkers.CallCheckerContext
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.storage.getValue
 
 private val ALLOWED_KCLASS_MEMBERS = setOf("simpleName", "isInstance")
+private val ALLOWED_CLASSES = setOf(
+    FqName("kotlin.reflect.KType"),
+    FqName("kotlin.reflect.KTypeProjection"),
+    FqName("kotlin.reflect.KTypeProjection.Companion"),
+    FqName("kotlin.reflect.KVariance")
+)
 
 class JsReflectionAPICallChecker(
-        module: ModuleDescriptor,
-        private val reflectionTypes: ReflectionTypes,
-        notFoundClasses: NotFoundClasses,
-        storageManager: StorageManager
+    module: ModuleDescriptor,
+    private val reflectionTypes: ReflectionTypes,
+    notFoundClasses: NotFoundClasses,
+    storageManager: StorageManager
 ) : AbstractReflectionApiCallChecker(module, notFoundClasses, storageManager) {
     override val isWholeReflectionApiAvailable: Boolean
         get() = false
@@ -47,6 +55,7 @@ class JsReflectionAPICallChecker(
     private val kClass by storageManager.createLazyValue { reflectionTypes.kClass }
 
     override fun isAllowedReflectionApi(descriptor: CallableDescriptor, containingClass: ClassDescriptor): Boolean =
-            super.isAllowedReflectionApi(descriptor, containingClass) ||
-            DescriptorUtils.isSubclass(containingClass, kClass) && descriptor.name.asString() in ALLOWED_KCLASS_MEMBERS
+        super.isAllowedReflectionApi(descriptor, containingClass) ||
+                DescriptorUtils.isSubclass(containingClass, kClass) && descriptor.name.asString() in ALLOWED_KCLASS_MEMBERS ||
+                containingClass.fqNameSafe in ALLOWED_CLASSES
 }

js/js.inliner/src/org/jetbrains/kotlin/js/inline/InlineAstVisitor.kt

@@ -14,6 +14,7 @@ import org.jetbrains.kotlin.js.backend.ast.metadata.inlineStrategy
 import org.jetbrains.kotlin.js.backend.ast.metadata.psiElement
 import org.jetbrains.kotlin.js.inline.clean.FunctionPostProcessor
 import org.jetbrains.kotlin.js.inline.clean.removeUnusedLocalFunctionDeclarations
+import org.jetbrains.kotlin.js.inline.clean.substituteKTypes
 import org.jetbrains.kotlin.js.inline.util.extractFunction
 import org.jetbrains.kotlin.js.inline.util.refreshLabelNames
 import org.jetbrains.kotlin.js.translate.expression.InlineMetadata
@@ -47,11 +48,11 @@ class InlineAstVisitor(
     }
 
     override fun endVisit(function: JsFunction, ctx: JsContext<*>) {
-        // Cleanup
         patchReturnsFromSecondaryConstructor(function)
         refreshLabelNames(function.body, function.scope)
         removeUnusedLocalFunctionDeclarations(function)
         FunctionPostProcessor(function).apply()
+        substituteKTypes(function)
     }
 
 

js/js.inliner/src/org/jetbrains/kotlin/js/inline/clean/substituteKTypes.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.js.inline.clean
+
+import org.jetbrains.kotlin.js.backend.ast.*
+import org.jetbrains.kotlin.js.backend.ast.metadata.SpecialFunction
+import org.jetbrains.kotlin.js.backend.ast.metadata.kType
+import org.jetbrains.kotlin.js.backend.ast.metadata.specialFunction
+
+// Replaces getReifiedTypeParameterKType(<Class Constructor>) with its KType
+fun substituteKTypes(root: JsNode) {
+    val visitor = object : JsVisitorWithContextImpl() {
+        override fun endVisit(invocation: JsInvocation, ctx: JsContext<in JsNode>) {
+            val qualifier = invocation.qualifier as? JsNameRef ?: return
+            if (qualifier.name?.specialFunction != SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE) return
+            val firstArg = invocation.arguments.first()
+            firstArg.kType?.let {
+                ctx.replaceMe(it)
+            }
+        }
+    }
+    visitor.accept(root)
+}

js/js.serializer/src/js-ast.proto

@@ -465,6 +465,7 @@ enum SpecialFunction {
     COROUTINE_RECEIVER = 8;
     SET_COROUTINE_RESULT = 9;
     GET_KCLASS = 10;
+    GET_REIFIED_TYPE_PARAMETER_KTYPE = 11;
 }
 
 

js/js.serializer/src/org/jetbrains/kotlin/serialization/js/ast/JsAstDeserializer.kt

@@ -558,6 +558,7 @@ class JsAstDeserializer(program: JsProgram, private val sourceRoots: Iterable<Fi
         JsAstProtoBuf.SpecialFunction.COROUTINE_RECEIVER -> SpecialFunction.COROUTINE_RECEIVER
         JsAstProtoBuf.SpecialFunction.SET_COROUTINE_RESULT -> SpecialFunction.SET_COROUTINE_RESULT
         JsAstProtoBuf.SpecialFunction.GET_KCLASS -> SpecialFunction.GET_KCLASS
+        JsAstProtoBuf.SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE -> SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE
     }
 
     private fun <T : JsNode> withLocation(fileId: Int?, location: Location?, action: () -> T): T {

js/js.serializer/src/org/jetbrains/kotlin/serialization/js/ast/JsAstProtoBuf.java

@@ -183,6 +183,10 @@ public final class JsAstProtoBuf {
      * <code>GET_KCLASS = 10;</code>
      */
     GET_KCLASS(9, 10),
+    /**
+     * <code>GET_REIFIED_TYPE_PARAMETER_KTYPE = 11;</code>
+     */
+    GET_REIFIED_TYPE_PARAMETER_KTYPE(10, 11),
     ;
 
     /**
@@ -225,6 +229,10 @@ public final class JsAstProtoBuf {
      * <code>GET_KCLASS = 10;</code>
      */
     public static final int GET_KCLASS_VALUE = 10;
+    /**
+     * <code>GET_REIFIED_TYPE_PARAMETER_KTYPE = 11;</code>
+     */
+    public static final int GET_REIFIED_TYPE_PARAMETER_KTYPE_VALUE = 11;
 
 
     public final int getNumber() { return value; }
@@ -241,6 +249,7 @@ public final class JsAstProtoBuf {
         case 8: return COROUTINE_RECEIVER;
         case 9: return SET_COROUTINE_RESULT;
         case 10: return GET_KCLASS;
+        case 11: return GET_REIFIED_TYPE_PARAMETER_KTYPE;
         default: return null;
       }
     }

js/js.serializer/src/org/jetbrains/kotlin/serialization/js/ast/JsAstSerializer.kt

@@ -601,6 +601,7 @@ class JsAstSerializer(private val jsAstValidator: ((JsProgramFragment, Set<JsNam
         SpecialFunction.COROUTINE_RECEIVER -> JsAstProtoBuf.SpecialFunction.COROUTINE_RECEIVER
         SpecialFunction.SET_COROUTINE_RESULT -> JsAstProtoBuf.SpecialFunction.SET_COROUTINE_RESULT
         SpecialFunction.GET_KCLASS -> JsAstProtoBuf.SpecialFunction.GET_KCLASS
+        SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE -> JsAstProtoBuf.SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE
     }
 
     private fun serialize(name: JsName): Int = nameMap.getOrPut(name) {

js/js.tests/test/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -17310,6 +17310,49 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/reflection/typeOf/multipleLayers.kt");
             }
 
+            @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/js")
+            @TestDataPath("$PROJECT_ROOT")
+            @RunWith(JUnit3RunnerWithInners.class)
+            public static class Js extends AbstractIrJsCodegenBoxTest {
+                private void runTest(String testDataFilePath) throws Exception {
+                    KotlinTestUtils.runTest0(this::doTest, TargetBackend.JS_IR, testDataFilePath);
+                }
+
+                public void testAllFilesPresentInJs() throws Exception {
+                    KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/typeOf/js"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JS_IR, true);
+                }
+
+                @TestMetadata("classes.kt")
+                public void testClasses() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/classes.kt");
+                }
+
+                @TestMetadata("inlineClasses.kt")
+                public void testInlineClasses() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/inlineClasses.kt");
+                }
+
+                @TestMetadata("kType.kt")
+                public void testKType() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/kType.kt");
+                }
+
+                @TestMetadata("manyTypeArguments.kt")
+                public void testManyTypeArguments() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/manyTypeArguments.kt");
+                }
+
+                @TestMetadata("multipleLayers.kt")
+                public void testMultipleLayers() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/multipleLayers.kt");
+                }
+
+                @TestMetadata("multipleModules.kt")
+                public void testMultipleModules() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/multipleModules.kt");
+                }
+            }
+
             @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/noReflect")
             @TestDataPath("$PROJECT_ROOT")
             @RunWith(JUnit3RunnerWithInners.class)

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -18465,6 +18465,49 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/reflection/typeOf/multipleLayers.kt");
             }
 
+            @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/js")
+            @TestDataPath("$PROJECT_ROOT")
+            @RunWith(JUnit3RunnerWithInners.class)
+            public static class Js extends AbstractJsCodegenBoxTest {
+                private void runTest(String testDataFilePath) throws Exception {
+                    KotlinTestUtils.runTest0(this::doTest, TargetBackend.JS, testDataFilePath);
+                }
+
+                public void testAllFilesPresentInJs() throws Exception {
+                    KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/typeOf/js"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JS, true);
+                }
+
+                @TestMetadata("classes.kt")
+                public void testClasses() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/classes.kt");
+                }
+
+                @TestMetadata("inlineClasses.kt")
+                public void testInlineClasses() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/inlineClasses.kt");
+                }
+
+                @TestMetadata("kType.kt")
+                public void testKType() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/kType.kt");
+                }
+
+                @TestMetadata("manyTypeArguments.kt")
+                public void testManyTypeArguments() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/manyTypeArguments.kt");
+                }
+
+                @TestMetadata("multipleLayers.kt")
+                public void testMultipleLayers() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/multipleLayers.kt");
+                }
+
+                @TestMetadata("multipleModules.kt")
+                public void testMultipleModules() throws Exception {
+                    runTest("compiler/testData/codegen/box/reflection/typeOf/js/multipleModules.kt");
+                }
+            }
+
             @TestMetadata("compiler/testData/codegen/box/reflection/typeOf/noReflect")
             @TestDataPath("$PROJECT_ROOT")
             @RunWith(JUnit3RunnerWithInners.class)

js/js.translator/src/org/jetbrains/kotlin/js/translate/context/Namer.java

@@ -75,6 +75,15 @@ public final class Namer {
     public static final String GET_KCLASS = "getKClass";
     public static final String GET_KCLASS_FROM_EXPRESSION = "getKClassFromExpression";
 
+    public static final String CREATE_KTYPE = "createKType";
+    public static final String MARK_KTYPE_NULLABLE = "markKTypeNullable";
+    public static final String CREATE_KTYPE_PARAMETER = "createKTypeParameter";
+    public static final String CREATE_REIFIED_KTYPE_PARAMETER = "getReifiedTypeParameterKType";
+    public static final String GET_START_KTYPE_PROJECTION = "getStarKTypeProjection";
+    public static final String CREATE_COVARIANT_KTYPE_PROJECTION = "createCovariantKTypeProjection";
+    public static final String CREATE_INVARIANT_KTYPE_PROJECTION = "createInvariantKTypeProjection";
+    public static final String CREATE_CONTRAVARIANT_KTYPE_PROJECTION = "createContravariantKTypeProjection";
+
     public static final String CALLEE_NAME = "$fun";
 
     public static final String CALL_FUNCTION = "call";

js/js.translator/src/org/jetbrains/kotlin/js/translate/intrinsic/functions/FunctionIntrinsics.kt

@@ -39,7 +39,8 @@ class FunctionIntrinsics {
         AsDynamicFIF,
         CoroutineContextFIF,
         SuspendCoroutineUninterceptedOrReturnFIF,
-        InterceptedFIF
+        InterceptedFIF,
+        TypeOfFIF
     )
 
     fun getIntrinsic(descriptor: FunctionDescriptor, context: TranslationContext): FunctionIntrinsic? {

js/js.translator/src/org/jetbrains/kotlin/js/translate/intrinsic/functions/factories/TypeOfFIF.kt

@@ -0,0 +1,111 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.js.translate.intrinsic.functions.factories
+
+import org.jetbrains.kotlin.descriptors.ClassifierDescriptor
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
+import org.jetbrains.kotlin.js.backend.ast.*
+import org.jetbrains.kotlin.js.backend.ast.metadata.SpecialFunction
+import org.jetbrains.kotlin.js.backend.ast.metadata.specialFunction
+import org.jetbrains.kotlin.js.translate.callTranslator.CallInfo
+import org.jetbrains.kotlin.js.translate.context.Namer
+import org.jetbrains.kotlin.js.translate.context.TranslationContext
+import org.jetbrains.kotlin.js.translate.expression.ExpressionVisitor
+import org.jetbrains.kotlin.js.translate.intrinsic.functions.basic.FunctionIntrinsic
+import org.jetbrains.kotlin.js.translate.utils.getReferenceToJsClass
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameUnsafe
+import org.jetbrains.kotlin.types.SimpleType
+import org.jetbrains.kotlin.types.TypeProjection
+import org.jetbrains.kotlin.types.Variance
+
+object TypeOfFIF : FunctionIntrinsicFactory {
+    override fun getIntrinsic(descriptor: FunctionDescriptor, context: TranslationContext): FunctionIntrinsic? =
+        Intrinsic.takeIf { descriptor.fqNameUnsafe.asString() == "kotlin.reflect.typeOf" }
+
+    object Intrinsic : FunctionIntrinsic() {
+        override fun apply(callInfo: CallInfo, arguments: List<JsExpression>, context: TranslationContext): JsExpression {
+            val type = callInfo.resolvedCall.typeArguments.values.single() as SimpleType
+            return KTypeConstructor(context).createKType(type)
+        }
+    }
+}
+
+class KTypeConstructor(val context: TranslationContext) {
+    fun callHelperFunction(name: String, vararg arguments: JsExpression) =
+        JsInvocation(context.getReferenceToIntrinsic(name), *arguments)
+
+    fun createKType(type: SimpleType): JsExpression {
+        val classifier: ClassifierDescriptor = type.constructor.declarationDescriptor!!
+
+        if (classifier is TypeParameterDescriptor && classifier.isReified) {
+            val kClassName = context.getNameForIntrinsic(SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE.suggestedName)
+            kClassName.specialFunction = SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE
+
+            val reifiedTypeParameterType = JsInvocation(kClassName.makeRef(), getReferenceToJsClass(classifier, context))
+            if (type.isMarkedNullable) {
+                return callHelperFunction(Namer.MARK_KTYPE_NULLABLE, reifiedTypeParameterType)
+            }
+
+            return reifiedTypeParameterType
+        }
+
+        val kClassifier = createKClassifier(classifier)
+        val arguments = JsArrayLiteral(type.arguments.map { createKTypeProjection(it) })
+        val isMarkedNullable = JsBooleanLiteral(type.isMarkedNullable)
+        return callHelperFunction(
+            Namer.CREATE_KTYPE,
+            kClassifier,
+            arguments,
+            isMarkedNullable
+        )
+    }
+
+    fun createKTypeProjection(tp: TypeProjection): JsExpression {
+        if (tp.isStarProjection) {
+            return callHelperFunction(Namer.GET_START_KTYPE_PROJECTION)
+        }
+
+        val factoryName = when (tp.projectionKind) {
+            Variance.INVARIANT -> Namer.CREATE_INVARIANT_KTYPE_PROJECTION
+            Variance.IN_VARIANCE -> Namer.CREATE_CONTRAVARIANT_KTYPE_PROJECTION
+            Variance.OUT_VARIANCE -> Namer.CREATE_COVARIANT_KTYPE_PROJECTION
+        }
+
+        val kType = createKType(tp.type as SimpleType)
+        return callHelperFunction(factoryName, kType)
+
+    }
+
+    fun createKClassifier(classifier: ClassifierDescriptor): JsExpression =
+        when (classifier) {
+            is TypeParameterDescriptor -> createKTypeParameter(classifier)
+            else -> ExpressionVisitor.getObjectKClass(context, classifier)
+        }
+
+    fun createKTypeParameter(typeParameter: TypeParameterDescriptor): JsExpression {
+        val name = JsStringLiteral(typeParameter.name.asString())
+        val upperBounds = JsArrayLiteral(typeParameter.upperBounds.map { createKType(it as SimpleType) })
+        val variance = when (typeParameter.variance) {
+            Variance.INVARIANT -> JsStringLiteral("invariant")
+            Variance.IN_VARIANCE -> JsStringLiteral("in")
+            Variance.OUT_VARIANCE -> JsStringLiteral("out")
+        }
+        if (typeParameter.isReified) {
+            val kClassName = context.getNameForIntrinsic(SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE.suggestedName)
+            kClassName.specialFunction = SpecialFunction.GET_REIFIED_TYPE_PARAMETER_KTYPE
+
+            return JsInvocation(kClassName.makeRef(), getReferenceToJsClass(typeParameter, context))
+        }
+
+        return callHelperFunction(
+            Namer.CREATE_KTYPE_PARAMETER,
+            name,
+            upperBounds,
+            variance
+        )
+    }
+}

js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/utils.kt

@@ -23,6 +23,7 @@ import org.jetbrains.kotlin.js.translate.context.Namer
 import org.jetbrains.kotlin.js.translate.context.TranslationContext
 import org.jetbrains.kotlin.js.translate.expression.ExpressionVisitor
 import org.jetbrains.kotlin.js.translate.intrinsic.functions.basic.FunctionIntrinsicWithReceiverComputed
+import org.jetbrains.kotlin.js.translate.intrinsic.functions.factories.KTypeConstructor
 import org.jetbrains.kotlin.js.translate.reference.ReferenceTranslator
 import org.jetbrains.kotlin.js.translate.utils.TranslationUtils.simpleReturnFunction
 import org.jetbrains.kotlin.psi.*
@@ -39,6 +40,7 @@ import org.jetbrains.kotlin.resolve.scopes.receivers.Receiver
 import org.jetbrains.kotlin.resolve.scopes.receivers.ReceiverValue
 import org.jetbrains.kotlin.resolve.source.getPsi
 import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.SimpleType
 import org.jetbrains.kotlin.types.TypeUtils
 import org.jetbrains.kotlin.utils.DFS
 
@@ -126,7 +128,9 @@ fun <T, S> List<T>.splitToRanges(classifier: (T) -> S): List<Pair<List<T>, S>> {
 }
 
 fun getReferenceToJsClass(type: KotlinType, context: TranslationContext): JsExpression =
-    getReferenceToJsClass(type.constructor.declarationDescriptor, context)
+    getReferenceToJsClass(type.constructor.declarationDescriptor, context).also {
+        it.kType = KTypeConstructor(context).createKType(type as SimpleType)
+    }
 
 fun getReferenceToJsClass(classifierDescriptor: ClassifierDescriptor?, context: TranslationContext): JsExpression {
     return when (classifierDescriptor) {

libraries/stdlib/js/src/kotlin/reflect/KTypeHelpers.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+// a package is omitted to get declarations directly under the module
+
+// TODO: Remove once JsReflectionAPICallChecker supports more reflection types
+@file:Suppress("Unsupported")
+
+import kotlin.reflect.*
+import kotlin.reflect.js.internal.*
+
+@JsName("createKType")
+internal fun createKType(
+    classifier: KClassifier,
+    arguments: Array<KTypeProjection>,
+    isMarkedNullable: Boolean
+) =
+    KTypeImpl(classifier, arguments.asList(), isMarkedNullable)
+
+@JsName("markKTypeNullable")
+internal fun markKTypeNullable(kType: KType) = KTypeImpl(kType.classifier!!, kType.arguments, true)
+
+@JsName("createKTypeParameter")
+internal fun createKTypeParameter(
+    name: String,
+    upperBounds: Array<KType>,
+    variance: String
+): KTypeParameter {
+    val kVariance = when (variance) {
+        "in" -> KVariance.IN
+        "out" -> KVariance.OUT
+        else -> KVariance.INVARIANT
+    }
+
+    return KTypeParameterImpl(name, upperBounds.asList(), kVariance, false)
+}
+
+@JsName("getStarKTypeProjection")
+internal fun getStarKTypeProjection(): KTypeProjection =
+    KTypeProjection.STAR
+
+@JsName("createCovariantKTypeProjection")
+internal fun createCovariantKTypeProjection(type: KType): KTypeProjection =
+    KTypeProjection.covariant(type)
+
+@JsName("createInvariantKTypeProjection")
+internal fun createInvariantKTypeProjection(type: KType): KTypeProjection =
+    KTypeProjection.invariant(type)
+
+@JsName("createContravariantKTypeProjection")
+internal fun createContravariantKTypeProjection(type: KType): KTypeProjection =
+    KTypeProjection.contravariant(type)

libraries/stdlib/js/src/kotlin/reflect/KTypeImpl.kt

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlin.reflect.js.internal
+
+import kotlin.reflect.*
+
+internal class KTypeImpl(
+    override val classifier: KClassifier,
+    override val arguments: List<KTypeProjection>,
+    override val isMarkedNullable: Boolean
+) : KType {
+    override val annotations: List<Annotation>
+        get() = emptyList()
+
+    override fun equals(other: Any?): Boolean =
+        other is KTypeImpl &&
+                classifier == other.classifier && arguments == other.arguments && isMarkedNullable == other.isMarkedNullable
+
+    override fun hashCode(): Int =
+        (classifier.hashCode() * 31 + arguments.hashCode()) * 31 + isMarkedNullable.hashCode()
+
+    override fun toString(): String {
+        val kClass = (classifier as? KClass<*>)
+        val classifierName = when {
+            kClass == null -> classifier.toString()
+            kClass.simpleName != null -> kClass.simpleName
+            else -> "(non-denotable type)"
+        }
+
+        val args =
+            if (arguments.isEmpty()) ""
+            else arguments.joinToString(", ", "<", ">") { it.asString() }
+        val nullable = if (isMarkedNullable) "?" else ""
+
+        return classifierName + args + nullable
+    }
+
+    // TODO: this should be the implementation of KTypeProjection.toString, see KT-30071
+    private fun KTypeProjection.asString(): String {
+        if (variance == null) return "*"
+        return variance.prefixString() + type.toString()
+    }
+}
+
+internal fun KVariance.prefixString() =
+    when (this) {
+        KVariance.INVARIANT -> ""
+        KVariance.IN -> "in "
+        KVariance.OUT -> "out "
+    }

libraries/stdlib/js/src/kotlin/reflect/KTypeParameterImpl.kt

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlin.reflect.js.internal
+
+import kotlin.reflect.*
+
+internal data class KTypeParameterImpl(
+    override val name: String,
+    override val upperBounds: List<KType>,
+    override val variance: KVariance,
+    override val isReified: Boolean
+) : KTypeParameter {
+    override fun toString(): String = name
+}

libraries/stdlib/js/src/kotlin/reflect/reflection.kt

@@ -5,7 +5,7 @@
 
 // a package is omitted to get declarations directly under the module
 
-import kotlin.reflect.KClass
+import kotlin.reflect.*
 import kotlin.reflect.js.internal.*
 
 @JsName("getKClass")
@@ -62,4 +62,3 @@ private fun <T : Any> getOrCreateKClass(jClass: JsClass<T>): KClass<T> {
         SimpleKClassImpl(jClass)
     }
 }
-