Summary

There's a minor type issue where new URL(input) does not accept URLs:

Should be:

constructor(input: string | URL, base?: string | URL);

Technically it should support other stringifiers, but may not be necessary for this fix.

Documentation

• https://nodejs.org/api/url.html#new-urlinput-base
• https://developer.mozilla.org/en-US/docs/Web/API/URL/URL#parameters

Examples/Use Cases

The follow example is valid in Node.js, but is not with @types/node:

const input = new URL('https://example.com');
const output = new URL(input);

This can be helpful in real-world use cases where an API may want to accept a URL as a string | URL:

export interface Config {
  /**
   * An endpoint to use.
   *
   * @example
   * 'https://localhost:8080/'
   */
  endpoint: string | URL;
}

function resolveURL (config: Config): URL {
  // currently a type error today
  return new URL(config.endpoint);
}