Fix sanitizeURL

[peolic]

Fixes this bug:
Sanitized URLs can become malformed - missing // after the protocol

Details

Code I tested this with:

Details

const twitterURL = new URL("https://www.twitter.com");
const instagramURL = new URL("https://www.instagram.com");

const sanitiseURL = (url, siteURL) => {
  if (!url) {
    return url;
  }

  if (url.startsWith("http://") || url.startsWith("https://")) {
    // just return the entire URL
    return url;
  }

  if (siteURL) {
    // if url starts with the site host, then prepend the protocol
    if (url.startsWith(siteURL.host)) {
      return `${siteURL.protocol}//${url}`;
    }

    // otherwise, construct the url from the protocol, host and passed url
    return `${siteURL.protocol}//${siteURL.host}/${url}`;
  }

  // just prepend the protocol - assume https
  return `https://${url}`;
};

const test = (url1, url2) => console.log(sanitiseURL(url1, url2));

test('mytest', twitterURL);
test('www.twitter.com/mytest', twitterURL);
test('http://www.twitter.com/mytest?u=e123', twitterURL);
test('https://twitter.com/mytest?u=e123', twitterURL);
test('twitter.com/mytest?');

test('mytest', instagramURL);
test('www.instagram.com/mytest', instagramURL);
test('http://www.instagram.com/mytest?u=e123', instagramURL);
test('https://instagram.com/mytest?u=e123', instagramURL);
test('instagram.com/mytest?');

[WithoutPants]

I've changed the base to master so that I can patch it into 0.2 directly.

Thanks for the fix. I was scratching my head for a bit trying to work out what the original problem was. Turns out that Chrome must fix up the malformed URL automatically. I had to jump to a different browser to see the bug.