[JS] Add test for KT-39378

js/js.tests/test/org/jetbrains/kotlin/js/test/es6/semantics/IrBoxJsES6TestGenerated.java

@@ -5237,6 +5237,11 @@ public class IrBoxJsES6TestGenerated extends AbstractIrBoxJsES6Test {
             runTest("js/js.translator/testData/box/jsModule/interfaces.kt");
         }
 
+        @TestMetadata("kt39378.kt")
+        public void testKt39378() throws Exception {
+            runTest("js/js.translator/testData/box/jsModule/kt39378.kt");
+        }
+
         @TestMetadata("topLevelVarargFun.kt")
         public void testTopLevelVarargFun() throws Exception {
             runTest("js/js.translator/testData/box/jsModule/topLevelVarargFun.kt");

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

@@ -5237,6 +5237,11 @@ public class IrBoxJsTestGenerated extends AbstractIrBoxJsTest {
             runTest("js/js.translator/testData/box/jsModule/interfaces.kt");
         }
 
+        @TestMetadata("kt39378.kt")
+        public void testKt39378() throws Exception {
+            runTest("js/js.translator/testData/box/jsModule/kt39378.kt");
+        }
+
         @TestMetadata("topLevelVarargFun.kt")
         public void testTopLevelVarargFun() throws Exception {
             runTest("js/js.translator/testData/box/jsModule/topLevelVarargFun.kt");

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

@@ -5252,6 +5252,11 @@ public class BoxJsTestGenerated extends AbstractBoxJsTest {
             runTest("js/js.translator/testData/box/jsModule/interfaces.kt");
         }
 
+        @TestMetadata("kt39378.kt")
+        public void testKt39378() throws Exception {
+            runTest("js/js.translator/testData/box/jsModule/kt39378.kt");
+        }
+
         @TestMetadata("topLevelVarargFun.kt")
         public void testTopLevelVarargFun() throws Exception {
             runTest("js/js.translator/testData/box/jsModule/topLevelVarargFun.kt");

js/js.translator/testData/box/jsModule/kt39378.js

@@ -0,0 +1,5 @@
+function ee() {
+    return {
+        ss: ['O' , 'K']
+    }
+}

js/js.translator/testData/box/jsModule/kt39378.kt

@@ -0,0 +1,34 @@
+// EXPECTED_REACHABLE_NODES: 1238
+
+// MODULE: lib
+// FILE: l.kt
+
+package l
+
+external interface E {
+    var ss: Array<String> // Effectively external property.
+}
+
+external fun ee(): E
+
+fun foo(): String {
+
+    val e = ee()
+
+    var result =  ""
+
+    for (s in e.ss) {
+        result += s
+    }
+
+    return result
+}
+
+// MODULE: main(lib)
+// FILE: m.kt
+
+import l.*
+
+fun box(): String {
+    return foo()
+}