[JS IR BE] Set Throwable subtype name in extendThrowable function

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/ThrowableLowering.kt

@@ -27,12 +27,9 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 
 
 class ThrowableLowering(val context: JsIrBackendContext) : FileLoweringPass {
-    private val unitType get() = context.irBuiltIns.unitType
     private val nothingNType get() = context.irBuiltIns.nothingNType
-    private val stringType get() = context.irBuiltIns.stringType
 
     private val throwableConstructors = context.throwableConstructors
-
     private val newThrowableFunction = context.newThrowableSymbol
     private val extendThrowableFunction = context.extendThrowableSymbol
 
@@ -84,30 +81,6 @@ class ThrowableLowering(val context: JsIrBackendContext) : FileLoweringPass {
             }
         }
 
-        override fun visitConstructor(declaration: IrConstructor, data: IrDeclarationParent): IrStatement {
-            val klass = data as IrClass
-            if (klass.defaultType.isThrowableTypeOrSubtype() && declaration.callsSuper(context.irBuiltIns)) {
-                val body = declaration.body as IrBlockBody
-                body.statements += IrDynamicOperatorExpressionImpl(
-                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
-                    unitType,
-                    IrDynamicOperator.EQ
-                ).also {
-                    it.receiver = IrDynamicMemberExpressionImpl(
-                        UNDEFINED_OFFSET, UNDEFINED_OFFSET,
-                        context.dynamicType,
-                        "name",
-                        JsIrBuilder.buildGetValue(klass.thisReceiver!!.symbol)
-                    )
-                    it.arguments.add(JsIrBuilder.buildString(stringType, klass.name.asString()))
-                }
-            }
-
-            declaration.transformChildren(this, data)
-
-            return declaration
-        }
-
         override fun visitDelegatingConstructorCall(expression: IrDelegatingConstructorCall, data: IrDeclarationParent): IrExpression {
             expression.transformChildren(this, data)
             if (expression.symbol !in throwableConstructors) return expression

libraries/stdlib/js-ir/runtime/coreRuntime.kt

@@ -97,11 +97,16 @@ internal fun extendThrowable(this_: dynamic, message: String?, cause: Throwable?
     js("Error").call(this_)
     this_.message = message ?: cause?.toString() ?: undefined
     this_.cause = cause
+    this_.name = JsObject.getPrototypeOf(this_).constructor.name
     captureStack(this_)
 }
 
 @JsName("Object")
-internal external class JsObject
+internal external class JsObject {
+    companion object {
+        fun getPrototypeOf(obj: Any?): dynamic
+    }
+}
 
 internal fun <T, R> boxIntrinsic(x: T): R = error("Should be lowered")
 internal fun <T, R> unboxIntrinsic(x: T): R = error("Should be lowered")