chore(cli): 去除@vuepress/cli依赖

packages/cli/src/utils/loadUserConfig.ts

@@ -0,0 +1,29 @@
+import { UserConfig, UserConfigLoader } from '../types';
+
+export const isPlainObject = <T extends Record<any, any> = Record<any, any>>(val: unknown): val is T =>
+  Object.prototype.toString.call(val) === '[object Object]';
+
+/**
+ * Check if a module is esm with `export default`
+ */
+export const hasExportDefault = <T = any>(mod: unknown): mod is { default: T } =>
+  isPlainObject(mod) && !!mod.__esModule && Object.prototype.hasOwnProperty.call(mod, 'default');
+
+export const loadUserConfigCjs: UserConfigLoader = async (userConfigPath) => {
+  const required = require(userConfigPath);
+  return hasExportDefault(required) ? required.default : required;
+};
+
+const loaderMap: [RegExp, UserConfigLoader][] = [[/\.(js|cjs|ts)$/, loadUserConfigCjs]];
+
+export const loadUserConfig = async (userConfigPath?: string): Promise<Partial<UserConfig>> => {
+  if (!userConfigPath) return {};
+
+  for (const [condition, loader] of loaderMap) {
+    if (condition.test(userConfigPath)) {
+      return loader(userConfigPath);
+    }
+  }
+
+  return {};
+};