@applicvision/js-toolbox/src/find-files.js

A collection of tools for modern JavaScript development

import fs from 'node:fs/promises'
import path from 'node:path'
import { pathToFileURL } from 'node:url'

async function readGitignore() {
	try {
		const gitIgnore = `${await fs.readFile('.gitignore')}`
		return gitIgnore.split('\n').filter(file => file)
	} catch (e) {
		if (e.code !== 'ENOENT') {
			throw e
		}
		return []
	}
}

/**
 * @template {boolean} [T = false]
 * @param {string} directory 
 * @param {Set<string>} ignoreSet 
 * @param {(filename: string) => boolean} fileMatcher 
 * @param {T} useFileUrls
 * @returns {Promise<T extends true ? URL[] : string[]>}
 */
async function scanDirectory(directory, ignoreSet, fileMatcher, useFileUrls) {
	const entries = await fs.readdir(directory, { withFileTypes: true })

	const filtered = entries
		.filter(entry => !entry.name.startsWith('.'))
		.filter(entry => !ignoreSet.has(entry.name))


	const found = await Promise.all(filtered.map(async entry => {
		if (entry.isDirectory()) {
			const directoryPath = path.join(directory, entry.name)
			return ignoreSet.has(directoryPath) ? [] : scanDirectory(directoryPath, ignoreSet, fileMatcher, useFileUrls)
		}
		if (fileMatcher(entry.name)) {
			const filePath = path.join(directory, entry.name)
			return useFileUrls ? pathToFileURL(filePath) : filePath
		}
		return []
	}))

	// @ts-ignore
	return found.flat()
}

/**
 * @template {boolean} [T=false]
 * @param {string} directory
 * @param {{ignoreSet?: Set<string>, fileMatcher?: (filename: string) => boolean, useFileUrls?: T}} options
 * @returns {Promise<T extends true ? URL[] : string[]>}
 */
export async function findFiles(directory = '.', { ignoreSet = new Set(), fileMatcher = () => true, useFileUrls } = {}) {
	const gitIgnoreEntries = await readGitignore()
	gitIgnoreEntries.forEach(ignoreEntry => ignoreSet.add(ignoreEntry))
	return scanDirectory(directory, ignoreSet, fileMatcher, useFileUrls)
}