refactor: use set for reserved words (#4298)

src/utils/exportNames.ts

@@ -18,7 +18,7 @@ export function assignExportsToMangledNames(
 					nameIndex += 9 * 64 ** (exportName.length - 1);
 					exportName = toBase64(nameIndex);
 				}
-			} while (RESERVED_NAMES[exportName] || exportsByName[exportName]);
+			} while (RESERVED_NAMES.has(exportName) || exportsByName[exportName]);
 		}
 		exportsByName[exportName] = variable;
 		exportNamesByVariable.set(variable, [exportName]);

src/utils/generateCodeSnippets.ts

@@ -79,7 +79,7 @@ export function getGenerateCodeSnippets({
 
 	const isValidPropName = reservedNamesAsProps
 		? (name: string): boolean => validPropName.test(name)
-		: (name: string): boolean => !RESERVED_NAMES[name] && validPropName.test(name);
+		: (name: string): boolean => !RESERVED_NAMES.has(name) && validPropName.test(name);
 
 	return {
 		_,

src/utils/reservedNames.ts

@@ -1,56 +1,50 @@
-export interface NameCollection {
-	[name: string]: true | null;
-	__proto__: null;
-}
-
-export const RESERVED_NAMES: NameCollection = {
-	__proto__: null,
-	await: true,
-	break: true,
-	case: true,
-	catch: true,
-	class: true,
-	const: true,
-	continue: true,
-	debugger: true,
-	default: true,
-	delete: true,
-	do: true,
-	else: true,
-	enum: true,
-	eval: true,
-	export: true,
-	extends: true,
-	false: true,
-	finally: true,
-	for: true,
-	function: true,
-	if: true,
-	implements: true,
-	import: true,
-	in: true,
-	instanceof: true,
-	interface: true,
-	let: true,
-	new: true,
-	null: true,
-	package: true,
-	private: true,
-	protected: true,
-	public: true,
-	return: true,
-	static: true,
-	super: true,
-	switch: true,
-	this: true,
-	throw: true,
-	true: true,
-	try: true,
-	typeof: true,
-	undefined: true,
-	var: true,
-	void: true,
-	while: true,
-	with: true,
-	yield: true
-};
+export const RESERVED_NAMES = new Set([
+	'await',
+	'break',
+	'case',
+	'catch',
+	'class',
+	'const',
+	'continue',
+	'debugger',
+	'default',
+	'delete',
+	'do',
+	'else',
+	'enum',
+	'eval',
+	'export',
+	'extends',
+	'false',
+	'finally',
+	'for',
+	'function',
+	'if',
+	'implements',
+	'import',
+	'in',
+	'instanceof',
+	'interface',
+	'let',
+	'new',
+	'null',
+	'package',
+	'private',
+	'protected',
+	'public',
+	'return',
+	'static',
+	'super',
+	'switch',
+	'this',
+	'throw',
+	'true',
+	'try',
+	'typeof',
+	'undefined',
+	'var',
+	'void',
+	'while',
+	'with',
+	'yield'
+]);

src/utils/safeName.ts

@@ -4,7 +4,7 @@ import { RESERVED_NAMES } from './reservedNames';
 export function getSafeName(baseName: string, usedNames: Set<string>): string {
 	let safeName = baseName;
 	let count = 1;
-	while (usedNames.has(safeName) || RESERVED_NAMES[safeName]) {
+	while (usedNames.has(safeName) || RESERVED_NAMES.has(safeName)) {
 		safeName = `${baseName}$${toBase64(count++)}`;
 	}
 	usedNames.add(safeName);