[JS IR BE] Support codegen for external objects and properties

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/transformers/irToJs/IrElementToJsExpressionTransformer.kt

@@ -79,9 +79,14 @@ class IrElementToJsExpressionTransformer : BaseIrElementToJsNodeTransformer<JsEx
 
     override fun visitGetObjectValue(expression: IrGetObjectValue, context: JsGenerationContext) = when (expression.symbol.owner.kind) {
         ClassKind.OBJECT -> {
+            val obj = expression.symbol.owner
             val className = context.getNameForSymbol(expression.symbol)
-            val getInstanceName = className.ident + "_getInstance"
-            JsInvocation(JsNameRef(getInstanceName))
+            if (obj.isEffectivelyExternal()) {
+                className.makeRef()
+            } else {
+                val getInstanceName = className.ident + "_getInstance"
+                JsInvocation(JsNameRef(getInstanceName))
+            }
         }
         else -> TODO()
     }
@@ -131,6 +136,19 @@ class IrElementToJsExpressionTransformer : BaseIrElementToJsNodeTransformer<JsEx
         val jsExtensionReceiver = expression.extensionReceiver?.accept(this, context)
         val arguments = translateCallArguments(expression, context)
 
+        // Transform external property accessor call
+        if (function is IrSimpleFunction) {
+            val property = function.correspondingProperty
+            if (property != null && property.isEffectivelyExternal()) {
+                val nameRef = JsNameRef(property.name.identifier, jsDispatchReceiver)
+                return when (function) {
+                    property.getter -> nameRef
+                    property.setter -> jsAssignment(nameRef, arguments.single())
+                    else -> error("Function must be an accessor of corresponding property")
+                }
+            }
+        }
+
         if (isNativeInvoke(expression)) {
             return JsInvocation(jsDispatchReceiver!!, arguments)
         }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/IrUtils.kt

@@ -403,9 +403,17 @@ fun IrFunction.isFakeOverriddenFromAny(): Boolean {
 fun IrCall.isSuperToAny() = superQualifier?.let { this.symbol.owner.isFakeOverriddenFromAny() } ?: false
 
 fun IrDeclaration.isEffectivelyExternal(): Boolean {
+
+    fun IrFunction.effectiveParentDeclaration(): IrDeclaration? =
+        when (this) {
+            is IrSimpleFunction -> correspondingProperty ?: parent as? IrDeclaration
+            else -> parent as? IrDeclaration
+        }
+
     return when (this) {
-        is IrFunction -> isExternal || parent is IrDeclaration && parent.isEffectivelyExternal()
+        is IrFunction -> isExternal || (effectiveParentDeclaration()?.isEffectivelyExternal() ?: false)
         is IrField -> isExternal || parent is IrDeclaration && parent.isEffectivelyExternal()
+        is IrProperty -> isExternal || parent is IrDeclaration && parent.isEffectivelyExternal()
         is IrClass -> isExternal || parent is IrDeclaration && parent.isEffectivelyExternal()
         else -> false
     }

js/js.translator/testData/box/crossModuleRef/topLevelProperty.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 // EXPECTED_REACHABLE_NODES: 1287
 // MODULE: lib
 // FILE: lib.kt

js/js.translator/testData/box/inheritance/interfaces/fromExternalInterface.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 // EXPECTED_REACHABLE_NODES: 1203
 
 external interface Foo {

js/js.translator/testData/box/jsModule/externalObject.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 // EXPECTED_REACHABLE_NODES: 1285
 // MODULE_KIND: AMD
 package foo