Issue 5314 - Allow hide emulation filters to be with a plain selector

chrome/content/elemHideEmulation.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 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 179 matching lines @@
 };
 
 const incompletePrefixRegexp = /[\s>+~]$/;
 
 function HasSelector(selectors)
 {
   this._innerSelectors = selectors;
 }
 
 HasSelector.prototype = {
+  requiresHiding: true,
+
   *getSelectors(prefix, subtree, styles)
   {
     for (let element of this.getElements(prefix, subtree, styles))
       yield [makeSelector(element, ""), element];
   },
 
   /**
    * Generator function returning selected elements.
    * @param {string} prefix the prefix for the selector.
    * @param {Node} subtree the subtree we work on.
@@ skipping 27 matching lines @@
     regexpString = propertyExpression.slice(1, -1)
       .replace("\\x7B ", "{").replace("\\x7D ", "}");
   }
   else
     regexpString = filterToRegExp(propertyExpression);
 
   this._regexp = new RegExp(regexpString, "i");
 }
 
 PropsSelector.prototype = {
-  hideWithStyleSheet: true,
+  preferHideWithSelector: true,
 
   *findPropsSelectors(styles, prefix, regexp)
   {
     for (let style of styles)
       if (regexp.test(style.style))
         for (let subSelector of style.subSelectors)
           yield prefix + subSelector;
   },
 
   *getSelectors(prefix, subtree, styles)
@@ skipping 43 matching lines @@
     let selectors = [];
     if (match.index > 0)
       selectors.push(new PlainSelector(selector.substr(0, match.index)));
 
     let startIndex = match.index + match[0].length;
     let content = parseSelectorContent(selector, startIndex);
     if (!content)
     {
       this.window.console.error(
         new SyntaxError("Failed to parse Adblock Plus " +
-                        `selector ${selector}, ` +
+                        `selector ${selector} ` +
                         "due to unmatched parentheses."));
       return null;
     }
     if (match[1] == "properties")
       selectors.push(new PropsSelector(content.text));
     else if (match[1] == "has")
     {
       let hasSelectors = this.parseSelector(content.text);
       if (hasSelectors == null)
         return null;
-      let hasSelector = new HasSelector(hasSelectors);
-      selectors.push(hasSelector);
+      selectors.push(new HasSelector(hasSelectors));
     }
     else
     {
       // this is an error, can't parse selector.
       this.window.console.error(
         new SyntaxError("Failed to parse Adblock Plus " +
                         `selector ${selector}, invalid ` +
                         `pseudo-class :-abp-${match[1]}().`));
       return null;
     }
@@ skipping 36 matching lines @@
         cssStyles.push(stringifyStyle(rule));
       }
     }
 
     let {document} = this.window;
     for (let pattern of this.patterns)
     {
       for (let selector of evaluate(pattern.selectors,
                                     0, "", document, cssStyles))
       {
-        if (pattern.selectors.some(s => s.hideWithStyleSheet))

[Wladimir Palant, 2017/06/19 08:28:32]

This logic reversal is wrong - any filter containing :-abp-properties() will now
be applied via stylesheets, even if it also contains :-abp-has().

It seems that we need two flags now: the requiresHiding flag we had before and a
new preferHideWithSelector set on PropsSelector class. The this check should be:

  if (!pattern.selectors.some(s => s.requiresHiding) && pattern.selectors.some(s
=> s.preferHideWithSelector))

That will make sure that we always hide for :-abp-has() and that we still hide
if neither :-abp-has() and :-abp-properties() are present.

[hub, 2017/06/19 13:37:15]

Done.

+        if (pattern.selectors.some(s => s.preferHideWithSelector) &&
+            !pattern.selectors.some(s => s.requiresHiding))
         {
           selectors.push(selector);
           selectorFilters.push(pattern.text);
         }
         else
         {
           for (let element of document.querySelectorAll(selector))
           {
             elements.push(element);
             elementFilters.push(pattern.text);
@@ skipping 27 matching lines @@
 
       if (this.patterns.length > 0)
       {
         let {document} = this.window;
         this.addSelectors(document.styleSheets);
         document.addEventListener("load", this.onLoad.bind(this), true);
       }
     });
   }
 };