Issue 7296 - Implement lightweight URL parsing

lib/url.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 31 matching lines @@
 /**
  * A <code>URLInfo</code> object represents information about a URL. It is
  * returned by <code>{@link parseURL}</code>.
  */
 class URLInfo
 {
   /**
    * Creates a <code>URLInfo</code> object.
    *
    * @param {string} href The entire URL.
-   * @param {string} [protocol] The protocol scheme of the URL, including the
+   * @param {string} protocol The protocol scheme of the URL, including the
    *   final <code>:</code>.
    * @param {string} [hostname] The hostname of the URL.
    *
    * @private
    */
-  constructor(href, protocol = "", hostname = "")
+  constructor(href, protocol, hostname = "")
   {
     this._href = href;
     this._protocol = protocol;
     this._hostname = hostname;
   }
 
   /**
    * The entire URL.
    * @type {string}
    */
@@ skipping 36 matching lines @@
  * <code>URL</code> object, this function is not robust and will give incorrect
  * results for invalid URLs. <em>Use this function with valid, normalized,
  * properly encoded (IDNA and percent-encoding) URLs only.</em>
  *
  * @param {string} url The URL to parse.
  * @returns {URLInfo} Information about the URL.
  */
 function parseURL(url)
 {
   let match = /^([^:]+:)(?:\/\/(?:[^/]*@)?(\[[^\]]*\]|[^:/]+))?/.exec(url);
-  return match ? new URLInfo(url, match[1], match[2]) : new URLInfo(url);

[hub, 2019/02/21 16:24:08]

if the parsing fails, then we only have a valid `_href` in URLInfo. I'm
wondering if instead we shouldn't just return null instead.

[Manish Jethani, 2019/02/23 07:32:05]

Actually since the function assumes that the URL will always be valid and
normalized, `match` should never be null (and if it is then an error should be
thrown).

I have updated the patch so it works this way now.

+  return new URLInfo(url, match[1], match[2]);
 }
 
 exports.parseURL = parseURL;
 
 /**
  * Normalizes a hostname.
  * @param {string} hostname
  * @returns {string}
  */
 function normalizeHostname(hostname)
@@ skipping 105 matching lines @@
   if (requestHostname == documentHostname)
     return false;
 
   if (!isDomain(requestHostname) || !isDomain(documentHostname))
     return true;
 
   return getBaseDomain(requestHostname) != getBaseDomain(documentHostname);
 }
 
 exports.isThirdParty = isThirdParty;