fix: readonly tuples were recognized as arrays

src/lib/converter/types.ts

@@ -950,8 +950,10 @@ const typeOperatorConverter: TypeConverter<ts.TypeOperatorNode> = {
             const args = context.checker
                 .getTypeArguments(type as ts.TypeReference)
                 .map((type) => convertType(context, type));
+
+            // TODO: wait for https://github.com/microsoft/TypeScript/issues/37711 and remove 'any' cast
             const inner =
-                type.objectFlags & ts.ObjectFlags.Tuple
+                (context as any).checker.isTupleType(type)
                     ? new TupleType(args)
                     : new ArrayType(args[0]);
 

src/test/converter/class/class.ts

@@ -56,6 +56,13 @@ export class TestClass {
      * arrow method
      */
     arrowMethod = () => {};
+
+    /**
+     * methodWithComplexArgs short text.
+     *
+     * @param readonlyTuple
+     */
+    methodWithComplexArgs(readonlyTuple: readonly [number, string]) {}
 }
 
 export class TestSubClass extends TestClass {