[K/JS] Make available transitive reexport for ES modules

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/HashCalculatorForIC.kt

@@ -139,8 +139,9 @@ internal fun CrossModuleReferences.crossModuleReferencesHashForIC() = HashCalcul
         update(importedModule.relativeRequirePath ?: "")
     }
 
-    updateForEach(transitiveJsExportFrom) { exportFrom ->
+    updateForEach(transitiveJsExportFrom) { transitiveExport ->
-        update(exportFrom.toString())
+        update(transitiveExport.internalName.toString())
+        update(transitiveExport.externalName)
     }
 
     updateForEach(exports.keys.sorted()) { tag ->

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

@@ -161,7 +161,7 @@ private class JsIrModuleCrossModuleReferecenceBuilder(
         }
 
         val transitiveExport = transitiveJsExportFrom.mapNotNull {
-            if (it.hasJsExports) import(it) else null
+            if (!it.hasJsExports) null else CrossModuleTransitiveExport(import(it), it.externalModuleName)
         }
         return CrossModuleReferences(
             moduleKind,
@@ -190,10 +190,12 @@ private class JsIrModuleCrossModuleReferecenceBuilder(
 
 class CrossModuleImport(val exportedAs: String, val moduleExporter: JsName)
 
+class CrossModuleTransitiveExport(val internalName: JsName, val externalName: String)
+
 class CrossModuleReferences(
     val moduleKind: ModuleKind,
     val importedModules: List<JsImportedModule>, // additional Kotlin imported modules
-    val transitiveJsExportFrom: List<JsName>, // the list of modules which provide their js exports for transitive export
+    val transitiveJsExportFrom: List<CrossModuleTransitiveExport>, // the list of modules which provide their js exports for transitive export
     val exports: Map<String, String>, // tag -> index
     val imports: Map<String, CrossModuleImport>, // tag -> import statement
 ) {

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

@@ -173,10 +173,20 @@ class Merger(
     }
 
     private fun transitiveJsExport(): List<JsStatement> {
-        val internalModuleName = ReservedJsNames.makeInternalModuleName()
+        return if (isEsModules) {
-        val exporterName = ReservedJsNames.makeJsExporterName()
+            crossModuleReferences.transitiveJsExportFrom.map {
-        return crossModuleReferences.transitiveJsExportFrom.map {
+                JsExport(JsExport.Subject.All, it.externalName)
-            JsInvocation(JsNameRef(exporterName, it.makeRef()), internalModuleName.makeRef()).makeStmt()
+            }
+        } else {
+            val internalModuleName = ReservedJsNames.makeInternalModuleName()
+            val exporterName = ReservedJsNames.makeJsExporterName()
+
+            crossModuleReferences.transitiveJsExportFrom.map {
+                JsInvocation(
+                    JsNameRef(exporterName, it.internalName.makeRef()),
+                    internalModuleName.makeRef()
+                ).makeStmt()
+            }
         }
     }
 

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/FirJsBoxTestGenerated.java

@@ -2367,6 +2367,12 @@ public class FirJsBoxTestGenerated extends AbstractFirJsBoxTest {
                 runTest("js/js.translator/testData/box/esModules/export/overriddenExternalMethodWithSameStableNameMethodInExportedFile.kt");
             }
 
+            @Test
+            @TestMetadata("reexport.kt")
+            public void testReexport() throws Exception {
+                runTest("js/js.translator/testData/box/esModules/export/reexport.kt");
+            }
+
             @Test
             @TestMetadata("reservedModuleName.kt")
             public void testReservedModuleName() throws Exception {
@@ -2920,6 +2926,12 @@ public class FirJsBoxTestGenerated extends AbstractFirJsBoxTest {
             runTest("js/js.translator/testData/box/export/overridenMethod.kt");
         }
 
+        @Test
+        @TestMetadata("reexport.kt")
+        public void testReexport() throws Exception {
+            runTest("js/js.translator/testData/box/export/reexport.kt");
+        }
+
         @Test
         @TestMetadata("reservedModuleName.kt")
         public void testReservedModuleName() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrBoxJsTestGenerated.java

@@ -2367,6 +2367,12 @@ public class IrBoxJsTestGenerated extends AbstractIrBoxJsTest {
                 runTest("js/js.translator/testData/box/esModules/export/overriddenExternalMethodWithSameStableNameMethodInExportedFile.kt");
             }
 
+            @Test
+            @TestMetadata("reexport.kt")
+            public void testReexport() throws Exception {
+                runTest("js/js.translator/testData/box/esModules/export/reexport.kt");
+            }
+
             @Test
             @TestMetadata("reservedModuleName.kt")
             public void testReservedModuleName() throws Exception {
@@ -2920,6 +2926,12 @@ public class IrBoxJsTestGenerated extends AbstractIrBoxJsTest {
             runTest("js/js.translator/testData/box/export/overridenMethod.kt");
         }
 
+        @Test
+        @TestMetadata("reexport.kt")
+        public void testReexport() throws Exception {
+            runTest("js/js.translator/testData/box/export/reexport.kt");
+        }
+
         @Test
         @TestMetadata("reservedModuleName.kt")
         public void testReservedModuleName() throws Exception {

js/js.translator/testData/box/esModules/export/reexport.kt

@@ -0,0 +1,31 @@
+// IGNORE_FIR
+// DONT_TARGET_EXACT_BACKEND: JS
+// ES_MODULES
+// EXPECTED_REACHABLE_NODES: 1283
+
+// MODULE: lib1
+// FILE: lib1.kt
+@JsExport
+fun bar() = "O"
+
+// MODULE: lib2(lib1)
+// FILE: lib2.kt
+
+@JsExport
+fun baz() = "K"
+
+// MODULE: main(lib2)
+// FILE: main.kt
+
+@JsExport
+fun result(o: String, k: String) = o + k
+
+// FILE: entry.mjs
+// ENTRY_ES_MODULE
+import { bar, baz, result } from "./reexport_v5.mjs";
+
+export function box() {
+    const o = bar();
+    const k = baz();
+    return result(o, k);
+}

js/js.translator/testData/box/export/reexport.kt

@@ -0,0 +1,30 @@
+// IGNORE_FIR
+// DONT_TARGET_EXACT_BACKEND: JS
+// EXPECTED_REACHABLE_NODES: 1283
+// RUN_PLAIN_BOX_FUNCTION
+// INFER_MAIN_MODULE
+
+// MODULE: lib1
+// FILE: lib1.kt
+@JsExport
+fun bar() = "O"
+
+// MODULE: lib2(lib1)
+// FILE: lib2.kt
+
+@JsExport
+fun baz() = "K"
+
+// MODULE: main(lib2)
+// FILE: main.kt
+
+@JsExport
+fun result(o: String, k: String) = o + k
+
+// FILE: test.js
+ function box() {
+    const { bar, baz, result } = this.main;
+    const o = bar();
+    const k = baz();
+    return result(o, k);
+}