Issue 6538, 6781 - Implement support for snippet filters

lib/filterClasses.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 66 matching lines @@
   }
 };
 
 /**
  * Cache for known filters, maps string representation to filter objects.
  * @type {Map.<string,Filter>}
  */
 Filter.knownFilters = new Map();
 
 /**
- * Regular expression that element hiding filters should match
+ * Regular expression that content filters should match
  * @type {RegExp}
  */
-Filter.elemhideRegExp = /^([^/*|@"!]*?)#([@?])?#(.+)$/;
+Filter.contentRegExp = /^([^/*|@"!]*?)#([@?$])?#(.+)$/;
 /**
  * Regular expression that RegExp filters specified as RegExps should match
  * @type {RegExp}
  */
 Filter.regexpRegExp = /^(@@)?\/.*\/(?:\$~?[\w-]+(?:=[^,\s]+)?(?:,~?[\w-]+(?:=[^,\s]+)?)*)?$/;
 /**
  * Regular expression that options on a RegExp filter should match
  * @type {RegExp}
  */
 Filter.optionsRegExp = /\$(~?[\w-]+(?:=[^,]+)?(?:,~?[\w-]+(?:=[^,]+)?)*)$/;
 /**
  * Regular expression that matches an invalid Content Security Policy
  * @type {RegExp}
  */
 Filter.invalidCSPRegExp = /(;|^) ?(base-uri|referrer|report-to|report-uri|upgrade-insecure-requests)\b/i;
 
 /**
  * Creates a filter of correct type from its text representation - does the
  * basic parsing and calls the right constructor then.
  *
  * @param {string} text   as in Filter()
  * @return {Filter}
  */
 Filter.fromText = function(text)
 {
   let filter = Filter.knownFilters.get(text);
   if (filter)
     return filter;
 
-  let match = (text.includes("#") ? Filter.elemhideRegExp.exec(text) : null);
+  let match = text.includes("#") ? Filter.contentRegExp.exec(text) : null;
   if (match)
   {
     let propsMatch;
     if (!match[2] &&
         (propsMatch = /\[-abp-properties=(["'])([^"']+)\1\]/.exec(match[3])))
     {
       // This is legacy CSS properties syntax, convert to current syntax
       let prefix = match[3].substr(0, propsMatch.index);
       let expression = propsMatch[2];
       let suffix = match[3].substr(propsMatch.index + propsMatch[0].length);
       return Filter.fromText(`${match[1]}#?#` +
           `${prefix}:-abp-properties(${expression})${suffix}`);
     }
 
-    filter = ElemHideBase.fromText(
-      text, match[1], match[2], match[3]
-    );
+    if (match[2] == "$")
+      filter = new SnippetFilter(text, match[1], match[3]);
+    else
+      filter = ElemHideBase.fromText(text, match[1], match[2], match[3]);

[hub, 2018/07/05 08:40:14]

I'm wonder if we shouldn't have this in ContentFilter.fromText() since we match
`contentRegExp`

But then we didn't have the syntax conversion in ElemHideBase.fromText() either,
which IMHO should be there too.

[Manish Jethani, 2018/07/06 13:32:15]

Yeah, this makes sense. Done.

   }
   else if (text[0] == "!")
     filter = new CommentFilter(text);
   else
     filter = RegExpFilter.fromText(text);
 
   Filter.knownFilters.set(filter.text, filter);
   return filter;
 };
 
@@ skipping 29 matching lines @@
   if (!text)
     return text;
 
   // Remove line breaks, tabs etc
   text = text.replace(/[^\S ]+/g, "");
 
   // Don't remove spaces inside comments
   if (/^ *!/.test(text))
     return text.trim();
 
-  // Special treatment for element hiding filters, right side is allowed to
-  // contain spaces
-  if (Filter.elemhideRegExp.test(text))
+  // Special treatment for content filters, right side is allowed to contain
+  // spaces
+  if (Filter.contentRegExp.test(text))
   {
-    let [, domains, separator, selector] = /^(.*?)(#[@?]?#?)(.*)$/.exec(text);
-    return domains.replace(/ +/g, "") + separator + selector.trim();
+    let [, domains, separator, script] = /^(.*?)(#[@?$]?#?)(.*)$/.exec(text);
+    return domains.replace(/ +/g, "") + separator + script.trim();
   }
 
   // For most regexp filters we strip all spaces, but $csp filter options
   // are allowed to contain single (non trailing) spaces.
   let strippedText = text.replace(/ +/g, "");
   if (!strippedText.includes("$") || !/\bcsp=/i.test(strippedText))
     return strippedText;
 
   let optionsMatch = Filter.optionsRegExp.exec(strippedText);
   if (!optionsMatch)
@@ skipping 777 matching lines @@
   RegExpFilter.call(this, text, regexpSource, contentType, matchCase, domains,
                     thirdParty, sitekeys);
 }
 exports.WhitelistFilter = WhitelistFilter;
 
 WhitelistFilter.prototype = extend(RegExpFilter, {
   type: "whitelist"
 });
 
 /**
- * Base class for element hiding filters
+ * Base class for content filters
  * @param {string} text see {@link Filter Filter()}
  * @param {string} [domains] Host names or domains the filter should be
  *                           restricted to
- * @param {string} selector   CSS selector for the HTML elements that should be
- *                            hidden
+ * @param {string} script    Script that should be executed
  * @constructor
  * @augments ActiveFilter
  */
-function ElemHideBase(text, domains, selector)
+function ContentFilter(text, domains, script)
 {
   ActiveFilter.call(this, text, domains || null);
 
-  // Braces are being escaped to prevent CSS rule injection.
-  this.selector = selector.replace("{", "\\7B ").replace("}", "\\7D ");
+  this.script = script;
 }
-exports.ElemHideBase = ElemHideBase;
+exports.ContentFilter = ContentFilter;
 
-ElemHideBase.prototype = extend(ActiveFilter, {
+ContentFilter.prototype = extend(ActiveFilter, {
   /**
    * @see ActiveFilter.domainSeparator
    */
   domainSeparator: ",",
 
   /**
+   * Script that should be executed
+   * @type {string}
+   */
+  script: null
+});
+
+/*
+ * Base class for element hiding filters
+ * @param {string} text see {@link Filter Filter()}
+ * @param {string} [domains] see {@link ContentFilter ContentFilter()}
+ * @param {string} selector  CSS selector for the HTML elements that should be
+ *                           hidden
+ * @constructor
+ * @augments ContentFilter
+ */
+function ElemHideBase(text, domains, selector)
+{
+  ContentFilter.call(this, text, domains, selector);
+}
+exports.ElemHideBase = ElemHideBase;
+
+ElemHideBase.prototype = extend(ContentFilter, {
+  /**
    * CSS selector for the HTML elements that should be hidden
    * @type {string}
    */
-  selector: null
+  get selector()

[Manish Jethani, 2018/06/26 19:28:15]

This can be a getter actually, so we don't create an additional property on
every ElemHideBase object.

I will make a separate change to lib/elemHide.js so it is accessed as few times
as necessary.

+  {
+    // Braces are being escaped to prevent CSS rule injection.
+    return this.script.replace("{", "\\7B ").replace("}", "\\7D ");
+  }
 });
 
 /**
  * Creates an element hiding filter from a pre-parsed text representation
  *
  * @param {string} text         same as in Filter()
  * @param {string} [domains]
  *   domains part of the text representation
  * @param {string} [type]
 *    rule type, either empty or @ (exception) or ? (emulation rule)
@@ skipping 71 matching lines @@
  */
 function ElemHideEmulationFilter(text, domains, selector)
 {
   ElemHideBase.call(this, text, domains, selector);
 }
 exports.ElemHideEmulationFilter = ElemHideEmulationFilter;
 
 ElemHideEmulationFilter.prototype = extend(ElemHideBase, {
   type: "elemhideemulation"
 });
+
+/**
+ * Class for snippet filters
+ * @param {string} text see Filter()
+ * @param {string} [domains] see ContentFilter()
+ * @param {string} script    Script that should be executed
+ * @constructor
+ * @augments ContentFilter
+ */
+function SnippetFilter(text, domains, script)
+{
+  ContentFilter.call(this, text, domains, script);
+}
+exports.SnippetFilter = SnippetFilter;
+
+SnippetFilter.prototype = extend(ContentFilter, {
+  type: "snippet"
+});