feat: add WARNING on usage top-level exportable declarations with non-consumable identifiers.

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

@@ -106,6 +106,8 @@ private val DIAGNOSTIC_FACTORY_TO_RENDERER by lazy {
         put(ErrorsJs.WRONG_EXPORTED_DECLARATION, "Declaration of such kind ({0}) can''t be exported to JS", STRING)
         put(ErrorsJs.NON_EXPORTABLE_TYPE, "Exported declaration uses non-exportable {0} type: {1}", STRING, RENDER_TYPE)
 
+        put(ErrorsJs.NON_CONSUMABLE_EXPORTED_IDENTIFIER, "Exported declaration contains non-consumable identifier '${0}', that can't be represented inside TS definitions and ESM", STRING)
+
         this
     }
 }

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/diagnostics/ErrorsJs.java

@@ -110,6 +110,8 @@ public interface ErrorsJs {
     DiagnosticFactory1<KtExpression, String> WRONG_EXPORTED_DECLARATION = DiagnosticFactory1.create(ERROR, DECLARATION_SIGNATURE_OR_DEFAULT);
     DiagnosticFactory2<PsiElement, String, KotlinType> NON_EXPORTABLE_TYPE = DiagnosticFactory2.create(WARNING, DECLARATION_SIGNATURE_OR_DEFAULT);
 
+    DiagnosticFactory1<PsiElement, String> NON_CONSUMABLE_EXPORTED_IDENTIFIER = DiagnosticFactory1.create(WARNING, DEFAULT);
+
     @SuppressWarnings("UnusedDeclaration")
     Object _initializer = new Object() {
         {

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

@@ -5,15 +5,19 @@
 
 package org.jetbrains.kotlin.js.resolve.diagnostics
 
+import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
-import org.jetbrains.kotlin.builtins.StandardNames
 import org.jetbrains.kotlin.builtins.isFunctionType
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.ClassKind.*
-import org.jetbrains.kotlin.js.resolve.diagnostics.JsExportDeclarationChecker.isExportable
+import org.jetbrains.kotlin.js.common.RESERVED_KEYWORDS
+import org.jetbrains.kotlin.js.naming.NameSuggestion
 import org.jetbrains.kotlin.js.translate.utils.AnnotationsUtils
+import org.jetbrains.kotlin.psi.KtAnnotationEntry
 import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.psi.KtNamedDeclaration
 import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.BindingTrace
 import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
 import org.jetbrains.kotlin.resolve.checkers.DeclarationChecker
 import org.jetbrains.kotlin.resolve.checkers.DeclarationCheckerContext
@@ -22,6 +26,7 @@ import org.jetbrains.kotlin.resolve.descriptorUtil.isExtensionProperty
 import org.jetbrains.kotlin.resolve.descriptorUtil.isInsideInterface
 import org.jetbrains.kotlin.resolve.inline.isInlineWithReified
 import org.jetbrains.kotlin.resolve.isInlineClass
+import org.jetbrains.kotlin.resolve.source.getPsi
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.isDynamic
 import org.jetbrains.kotlin.types.typeUtil.*
@@ -61,6 +66,8 @@ object JsExportDeclarationChecker : DeclarationChecker {
             reportWrongExportedDeclaration("expect")
         }
 
+        validateDeclarationOnConsumableName(declaration, descriptor, trace)
+
         when (descriptor) {
             is FunctionDescriptor -> {
                 for (typeParameter in descriptor.typeParameters) {
@@ -201,4 +208,33 @@ object JsExportDeclarationChecker : DeclarationChecker {
 
         return descriptor.isEffectivelyExternal() || AnnotationsUtils.isExportedObject(descriptor, bindingContext)
     }
+
+    private fun validateDeclarationOnConsumableName(
+        declaration: KtDeclaration,
+        declarationDescriptor: DeclarationDescriptor,
+        trace: BindingTrace
+    ) {
+        if (!declarationDescriptor.isTopLevelInPackage() || declarationDescriptor.name.isSpecial) return
+
+        val name = declarationDescriptor.getKotlinOrJsName()
+
+        if (name !in RESERVED_KEYWORDS && NameSuggestion.sanitizeName(name) == name) return
+
+        val reportTarget = declarationDescriptor.getJsNameArgument() ?: declaration.getIdentifier()
+
+        trace.report(ErrorsJs.NON_CONSUMABLE_EXPORTED_IDENTIFIER.on(reportTarget, name))
+    }
+
+    private fun DeclarationDescriptor.getKotlinOrJsName(): String {
+        return AnnotationsUtils.getJsName(this) ?: name.identifier
+    }
+
+    private fun KtDeclaration.getIdentifier(): PsiElement {
+        return (this as KtNamedDeclaration).nameIdentifier!!
+    }
+
+    private fun DeclarationDescriptor.getJsNameArgument(): PsiElement? {
+        val jsNameAnnotation = AnnotationsUtils.getJsNameAnnotation(this) ?: return null
+        return (jsNameAnnotation.source.getPsi() as KtAnnotationEntry).valueArgumentList?.arguments?.first()
+    }
 }

js/js.frontend/src/org/jetbrains/kotlin/js/translate/utils/AnnotationsUtils.java

@@ -39,7 +39,7 @@ import java.util.List;
 import static org.jetbrains.kotlin.resolve.descriptorUtil.DescriptorUtilsKt.isEffectivelyExternal;
 
 public final class AnnotationsUtils {
-    private static final String JS_NAME = "kotlin.js.JsName";
+    public static final FqName JS_NAME = new FqName("kotlin.js.JsName");
     private static final FqName JS_EXPORT = new FqName("kotlin.js.JsExport");
     public static final FqName JS_MODULE_ANNOTATION = new FqName("kotlin.js.JsModule");
     private static final FqName JS_NON_MODULE_ANNOTATION = new FqName("kotlin.js.JsNonModule");
@@ -172,7 +172,7 @@ public final class AnnotationsUtils {
 
     @Nullable
     public static AnnotationDescriptor getJsNameAnnotation(@NotNull DeclarationDescriptor descriptor) {
-        return descriptor.getAnnotations().findAnnotation(new FqName(JS_NAME));
+        return descriptor.getAnnotations().findAnnotation(JS_NAME);
     }
 
     @Nullable