[K/JS] Exclude default from the regular reserved keywords to give ability to export declarations with default export ^KT-54480 Fixed

fix(KT-54480): exclude default from the regular reserved keywords to give ability to export intities with default export.

Merge-request: KT-MR-7459
Merged-by: Artem Kobzar <Artem.Kobzar@jetbrains.com>

compiler/testData/diagnostics/testsWithJsStdLib/export/nonConsumableIdentifiers.kt

@@ -24,6 +24,10 @@ val bar = 4
 @JsName(<!NON_CONSUMABLE_EXPORTED_IDENTIFIER!>"super"<!>)
 class Baz
 
+@JsExport
+@JsName("default")
+class DefDef
+
 @JsExport
 class Test {
     fun instanceof() {}

compiler/testData/diagnostics/testsWithJsStdLib/export/nonConsumableIdentifiers.txt

@@ -13,6 +13,13 @@ package foo {
         public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 
+    @kotlin.js.JsExport @kotlin.js.JsName(name = "default") public final class DefDef {
+        public constructor DefDef()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+
     @kotlin.js.JsExport public object NaN {
         private constructor NaN()
         public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean

js/js.ast/src/org/jetbrains/kotlin/js/common/IdentifierPolicy.kt

@@ -51,9 +51,11 @@ fun String.isValidES5Identifier(): Boolean {
     return true
 }
 
-val RESERVED_KEYWORDS: Set<String> = setOf(
+val SPECIAL_KEYWORDS: Set<String> = setOf("default")
+
+val RESERVED_KEYWORDS: Set<String> = SPECIAL_KEYWORDS + setOf(
     // keywords
-    "await", "break", "case", "catch", "continue", "debugger", "default", "delete", "do", "else", "finally", "for", "function", "if",
+    "await", "break", "case", "catch", "continue", "debugger", "delete", "do", "else", "finally", "for", "function", "if",
     "in", "instanceof", "new", "return", "switch", "this", "throw", "try", "typeof", "var", "void", "while", "with",
 
     // future reserved words

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

@@ -11,6 +11,7 @@ import org.jetbrains.kotlin.builtins.isFunctionType
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.ClassKind.*
 import org.jetbrains.kotlin.js.common.RESERVED_KEYWORDS
+import org.jetbrains.kotlin.js.common.SPECIAL_KEYWORDS
 import org.jetbrains.kotlin.js.naming.NameSuggestion
 import org.jetbrains.kotlin.js.translate.utils.AnnotationsUtils
 import org.jetbrains.kotlin.psi.KtAnnotationEntry
@@ -212,7 +213,7 @@ object JsExportDeclarationChecker : DeclarationChecker {
 
         val name = declarationDescriptor.getKotlinOrJsName()
 
-        if (name !in RESERVED_KEYWORDS && NameSuggestion.sanitizeName(name) == name) return
+        if (name in SPECIAL_KEYWORDS || (name !in RESERVED_KEYWORDS && NameSuggestion.sanitizeName(name) == name)) return
 
         val reportTarget = declarationDescriptor.getJsNameArgument() ?: declaration.getIdentifier()