💻

• Would you like to work on a fix?

How are you using Babel?

Programmatic API (babel.transform, babel.parse)

Input code

import * as babel from "@babel/core";

const source = `
export default function Component() {
  return (
    <ul>
      <li>One</li>
      <li>Two</li>
      <li>Three</li>
    </ul>
  );
}`;

const result = babel.transformSync(source, {
  filename: "source.tsx",
  plugins: ["@babel/plugin-syntax-jsx"],
  configFile: false,
  babelrc: false,
  retainLines: true,
});

console.log(result.code);

Configuration file name

No response

Configuration

No response

Current and expected behavior

Additional newlines that don't exist in source are added to the output:

Actual

export default function Component() {
  return (
    <ul>

      <li>One</li>

      <li>Two</li>

      <li>Three</li>

    </ul>);

}

Expected

export default function Component() {
  return (
    <ul>
      <li>One</li>
      <li>Two</li>
      <li>Three</li>
    </ul>
  );
}

Environment

System:
OS: Windows 10 10.0.19044
Binaries:
Node: 16.17.0 - C:\Program Files\nodejs\node.EXE
Yarn: 1.22.19 - ~\AppData\Roaming\npm\yarn.CMD
npm: 8.15.0 - ~\node_modules.bin\npm.CMD
npmPackages:
@babel/core: 7.17.5 => 7.17.5
@babel/plugin-syntax-jsx: 7.17.12 => 7.17.12

Possible solution

No response

Additional context

This bug was likely introduced in @babel/generator@7.18.9. When I pinned the version to 7.18.7, the output was correct.