Comments are stripped when all code from a file is removed by @babel/plugin-transform-typescript

[andsouto]

Bug Report

• [ ] I would like to work on a fix!

Current behavior When processing a file where all its contents is removed during transpilation, comments are also removed. If some code is kept, comments are kept.

• REPL

But if you add any additional code to the file it works in the exepcted way:

• REPL

Input Code

/**
 * @typedef {object} user
 * @property {string} [id]
 */
export interface User {
    id?: string;
}

Expected behavior Comments are kept even when all the content is stripped.

Babel Configuration (babel.config.js, .babelrc, package.json#babel, cli command, .eslintrc)

• Filename: babel.config.js

{
    plugins: [
        '@babel/plugin-transform-typescript',
    ],
}

Environment

• Babel version(s): 7.10.4
• How you are using Babel: Reproduced in babel repl

[babel-bot]

Hey @kai670! We really appreciate you taking the time to report an issue. The collaborators on this project attempt to help as many people as possible, but we're a limited number of volunteers, so it's possible this won't be addressed swiftly.

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