index.js

// original
// https://github.com/vuejs/vuepress/blob/ba7f586e2e8173e5e30c345ea6a92ff213925a2e/packages/%40vuepress/theme-default/util/index.js#L188-L215

/**
 * @param { Route } route
 * @param { Array<string|string[]> | Array<SidebarGroup> | [link: string]: SidebarConfig } config
 * @returns { base: string, config: SidebarConfig }
 */
export function resolveMatchingConfig (regularPath, config) {
  if (Array.isArray(config)) {
    return {
      base: '/',
      config: config
    }
  }
  for (const base in config) {
    // - if (ensureEndingSlash(regularPath).indexOf(encodeURI(base)) === 0) {
    // + if (exists(regularPath, config[base])) {
    if (exists(regularPath, config[base])) {
      return {
        base,
        config: config[base]
      }
    }
  }
  return {}
}

function exists (regularPath, arrayConfig) {
  if (arrayConfig === undefined) {
    return false
  }
  for (const item of arrayConfig) {
    if (item instanceof Array) {
      const path = item[0]
      if (ensureEndingSlash(regularPath) === ensureEndingSlash(path)) {
        return true
      }
    } else {
      if (exists(regularPath, item.children)) {
        return true
      }
    }
  }
  return false
}