fileProcessor.js

import { relative } from 'node:path'
import { promises as fsAsync } from 'node:fs'
import { clock } from '@dr-js/core/module/common/time.js'
import { binary, time, padTable } from '@dr-js/core/module/common/format.js'

const processFileList = async ({
  kit, kitLogger = kit,
  fileList, processor,
  outputPath = (kit && kit.fromOutput()) || ''
}) => {
  kitLogger.padLog(`process ${fileList.length} file`)

  const table = []
  const totalTimeStart = clock()
  let totalSizeSource = 0
  let totalSizeDelta = 0
  for (const filePath of fileList) {
    const inputString = String(await fsAsync.readFile(filePath))
    const outputString = await processor(inputString, filePath)
    const sizeSource = (await fsAsync.stat(filePath)).size
    let sizeOutput
    if (inputString === outputString) {
      kitLogger.devLog(`process skipped ${filePath}`)
      sizeOutput = sizeSource
    } else if (outputString) {
      await fsAsync.writeFile(filePath, outputString)
      sizeOutput = (await fsAsync.stat(filePath)).size
    } else { // TODO: maybe not necessary to delete an empty file?
      await fsAsync.unlink(filePath)
      sizeOutput = 0
    }
    const sizeDelta = sizeOutput - sizeSource
    totalSizeSource += sizeSource
    totalSizeDelta += sizeDelta
    kitLogger.isVerbose && table.push([
      `∆ ${(100 * sizeDelta / sizeSource).toFixed(2)}% (${binary(sizeDelta)}B)`,
      `${relative(outputPath, filePath)}`
    ])
  }

  kitLogger.isVerbose && table.push([ '--', '--' ])
  table.push([
    `∆ ${(100 * totalSizeDelta / totalSizeSource).toFixed(2)}% (${binary(totalSizeDelta)}B)`,
    `TOTAL of ${fileList.length} file (${binary(totalSizeSource)}B|${time(clock() - totalTimeStart)})`
  ])

  kitLogger.log(`result:\n  ${padTable({ table, padFuncList: [ 'L', 'L' ], cellPad: ' | ', rowPad: '\n  ' })}`)

  return totalSizeDelta
}

const fileProcessorBabel = (inputString) => inputString
  .replace(/['"]use strict['"];?\s*/g, '')
  .replace(/Object\.defineProperty\(exports,\s*['"]__esModule['"],\s*{\s*value:\s*(true|!0)\s*}\)[;,]?\s*/g, '') // drop babel marker, drop this will make the `_interopRequireDefault` return `module.exports` instead of `module.exports.default`, but there's no `export default`: https://github.com/airbnb/javascript/issues/1365
  .replace(/(exports\.\w+\s*=\s*)+(undefined|void 0)[;,]?\s*/g, '') // drop the duplicate pre-define of exports generated by babel
  .replace(/\/\*\* @deprecated \*\/;?\s+const/g, '/** @deprecated */ const') // compact `/** @deprecated */ const ...` combo
  .replace(/[\n\r]{2,}/g, '\n') // remove multi-blank lines // TODO: may also change lines in `` strings
  .replace(/^[\n\r]+/, '') // remove leading blank line

export {
  processFileList,
  fileProcessorBabel
}