findFile.ts

// Adapted from https://github.com/lukeed/escalade/blob/2477005/src/sync.js
import { dirname, join } from 'path'
import { readdirSync } from 'fs'

/**
 * Search each parent directory until a string or false is returned.
 */
export function findFile(
  dir: string,
  callback: (names: string[], dir: string) => string | false | undefined
) {
  let tmp: ReturnType<typeof callback>
  for (;;) {
    tmp = callback(readdirSync(dir), dir)
    if (tmp !== undefined) {
      return tmp ? join(dir, tmp) : undefined
    }
    dir = dirname((tmp = dir))
    if (tmp === dir) return
  }
}