babel-plugin-transform-fs-promises

A Babel plugin to transform fs/promises imports and requires into their fs equivalents for compatibility with Node.js 14 and below.

Both fs/promises and node:fs/promises module specifiers are supported.

Compatible with Babel@^7.0.0.

Installation

npm install babel-plugin-transform-fs-promises --save-dev

Usage

Via .babelrc / babel.config.json

{
  "plugins": ["babel-plugin-transform-fs-promises"]
}

Via babel.config.js

module.exports = {
  plugins: ["babel-plugin-transform-fs-promises"],
};

Via Babel API

import { transformSync } from "@babel/core";
import babelPluginTransformFsPromises from "babel-plugin-transform-fs-promises";

const result = transformSync(code, {
  plugins: [babelPluginTransformFsPromises],
});

Transformations

The plugin handles all common ways of importing fs/promises (and its node: prefixed form node:fs/promises).

CJS — require()

| Input | Output | |---|---| | require('fs/promises') | require('fs').promises | | module.require('fs/promises') | module.require('fs').promises |

Example:

// Input
const fs = require("fs/promises");
const { readFile, stat } = require("node:fs/promises");

// Output
const fs = require("fs").promises;
const { readFile, stat } = require("fs").promises;

ESM — Dynamic import()

| Input | Output | |---|---| | import('fs/promises') | import('fs').then(_esModule => _esModule.promises) |

Example:

// Input
const fs = await import("fs/promises");

// Output
const fs = await import("fs").then(_esModule => _esModule.promises);

ESM — Default import

| Input | Output | |---|---| | import fs from 'fs/promises' | import { promises as fs } from 'fs' |

Example:

// Input
import fs from "fs/promises";

// Output
import { promises as fs } from "fs";

ESM — Named imports

| Input | Output | |---|---| | import { readFile } from 'fs/promises' | import { promises as _promises } from 'fs'; const { readFile } = _promises; |

Example:

// Input
import { readFile, stat } from "fs/promises";

// Output
import { promises as _promises } from "fs";
const { readFile, stat } = _promises;

ESM — Default + named imports

| Input | Output | |---|---| | import fs, { readFile } from 'fs/promises' | import fs, { promises as _promises } from 'fs'; const { readFile } = _promises; |

Example:

// Input
import fs, { readFile } from "fs/promises";

// Output
import fs, { promises as _promises } from "fs";
const { readFile } = _promises;

ESM — Namespace import

| Input | Output | |---|---| | import * as fs from 'fs/promises' | import { promises as fs } from 'fs' |

Example:

// Input
import * as fs from "fs/promises";

// Output
import { promises as fs } from "fs";

ESM — Export all

| Input | Output | |---|---| | export * from 'fs/promises' | import { promises as _promises } from 'fs'; export default _promises; |

Example:

// Input
export * from "fs/promises";

// Output
import { promises as _promises } from "fs";
export default _promises;

ESM — Named re-exports

| Input | Output | |---|---| | export { readFile } from 'fs/promises' | import { promises as _promises } from 'fs'; const { readFile: _readFile } = _promises; export { _readFile as readFile }; |

Example:

// Input
export { readFile } from "fs/promises";

// Output
import { promises as _promises } from "fs";
const { readFile: _readFile } = _promises;
export { _readFile as readFile };

Relative

• transform-fs-promises-webpack-plugin

License

The Anti 996 License