babel-prettier-parser

0.10.8 verified Sat Apr 25 auth: no javascript

A Prettier parser wrapper that enables formatting of JavaScript/TypeScript code containing experimental or non-standard syntaxes that Babel can transform, such as pipeline operators, decorators, and do expressions. Version 0.10.8 is the latest stable release with no fixed release cadence. It ships TypeScript types and requires Prettier ^2.2.1 as a peer dependency. Unlike Prettier's default Babel parser, this package allows parsing of code with Babel plugins that are not included by default in Prettier, making it suitable for projects using advanced ECMAScript proposals. However, it is a niche tool with limited community adoption and may have compatibility issues with future Prettier versions.

Common errors

error Cannot find module 'babel-prettier-parser' ↓

cause Package not installed or missed in dependencies.

fix

Run npm install babel-prettier-parser --save-dev

error Must use import to load ES Module: require() of ES modules is not supported ↓

cause CJS require not supported for ESM-only package.

fix

Use import syntax or dynamic import().

error TypeError: parse is not a function ↓

cause Default import is an object, not a function.

fix

Use { parse } instead of default import.

Warnings

breaking Version 0.8.0: parse now returns an object with a `type` property. Old code expects an AST node. ↓

fix Access the root node via result.ast or similar; check the updated API.

deprecated The `text` parameter in parse has been deprecated in favor of `code`. ↓

fix Use { code: source } instead of { text: source }.

gotcha The parser does not support all Prettier options; custom Babel plugins must be passed explicitly. ↓

fix Always pass the required Babel plugins in the options object to parse.

Install

npm install babel-prettier-parser

yarn add babel-prettier-parser

pnpm add babel-prettier-parser

Imports

parse

wrong

const { parse } = require('babel-prettier-parser')

correct

import { parse } from 'babel-prettier-parser'

ESM-only since v0.10.0; TypeScript types included.

default

wrong

import { default as parse } from 'babel-prettier-parser'

correct

import bpParser from 'babel-prettier-parser'; bpParser.parse(source)

Default export is an object with parse method; named export `parse` is preferred.

BABEL_PARSER_OPTIONS

wrong

import BABEL_PARSER_OPTIONS from 'babel-prettier-parser'

correct

import { BABEL_PARSER_OPTIONS } from 'babel-prettier-parser'

Named constant for passing options to Babel; not a default export.

Quickstart

Demonstrates configuring Prettier to use babel-prettier-parser for formatting code with do expressions.

import prettier from 'prettier';
import { parse } from 'babel-prettier-parser';

const code = `const x = do { if (true) 1; else 2; };`;

// Register the parser with Prettier
prettier.format(code, {
  parser: 'babel',
  plugins: [{
    parsers: {
      babel: {
        parse: (text, parsers) => {
          const ast = parse(text, {
            plugins: ['doExpressions'],
            sourceType: 'module',
          });
          // Transform AST to Prettier-compatible AST if needed
          return ast;
        },
      },
    },
  }],
}).then(result => console.log(result));