Upgrade to ESLint 9

src/middleware.ts

@@ -1,31 +1,10 @@
-import type { ESLintConfig, KnownExtends, Settings } from '@aet/eslint-define-config';
-import type { Merge, SetRequired } from 'type-fest';
+import type { Linter } from 'eslint';
 
-import type { RuleOptions } from './index';
+type MiddlewareResult = Linter.Config | Linter.Config[];
 
-type OptionalObjectKey<T> = Exclude<
-  {
-    [Key in keyof T]: undefined | any[] extends T[Key]
-      ? Key
-      : undefined | Record<any, any> extends T[Key]
-        ? Key
-        : never;
-  }[keyof T],
-  undefined
->;
+export type Middleware =
+  | (() => Promise<MiddlewareResult>)
+  | (() => Promise<{ default: MiddlewareResult }>);
 
-export type MiddlewareConfig = Merge<
-  SetRequired<ESLintConfig, OptionalObjectKey<ESLintConfig>>,
-  { extends: KnownExtends[] }
->;
-
-export interface MiddlewareFunctions {
-  addRules(rules: Partial<RuleOptions>): void;
-  addSettings(settings: Partial<Settings>): void;
-}
-
-export type Middleware = (config: MiddlewareConfig, helpers: MiddlewareFunctions) => void;
-
-export function defineMiddleware(middleware: Middleware): Middleware {
-  return middleware;
-}
+// eslint-disable-next-line unicorn/prevent-abbreviations
+export const def = <T>(module: { default: T }): T => module.default;