Issue 5344 - Element hiding emulation exceptions

lib/filterClasses.js

Index: lib/filterClasses.js
===================================================================
--- a/lib/filterClasses.js
+++ b/lib/filterClasses.js
@@ -82,17 +82,17 @@
  * @type {Object}
  */
 Filter.knownFilters = Object.create(null);
 
 /**
  * Regular expression that element hiding filters should match
  * @type {RegExp}
  */
-Filter.elemhideRegExp = /^([^/*|@"!]*?)#([@?])?#(.+)$/;
+Filter.elemhideRegExp = /^([^/*|@"!]*?)#([@?^])?#(.+)$/;
 /**
  * Regular expression that RegExp filters specified as RegExps should match
  * @type {RegExp}
  */
 Filter.regexpRegExp = /^(@@)?\/.*\/(?:\$~?[\w-]+(?:=[^,\s]+)?(?:,~?[\w-]+(?:=[^,\s]+)?)*)?$/;
 /**
  * Regular expression that options on a RegExp filter should match
  * @type {RegExp}
@@ -943,43 +943,63 @@
  *
  * @param {string} text         same as in Filter()
  * @param {string?} domain
  *   domain part of the text representation
  * @param {string?} type
 *    rule type, either empty or @ (exception) or ? (emulation rule)
  * @param {string} selector     raw CSS selector
  * @return {ElemHideFilter|ElemHideException|
- *          ElemHideEmulationFilter|InvalidFilter}
+ *          ElemHideEmulationFilter|ElemHideEmulationException|InvalidFilter}
  */
 ElemHideBase.fromText = function(text, domain, type, selector)
 {
   // We don't allow ElemHide filters which have any empty domains.
   // Note: The ElemHide.prototype.domainSeparator is duplicated here, if that
   // changes this must be changed too.
   if (domain && /(^|,)~?(,|$)/.test(domain))
     return new InvalidFilter(text, "filter_invalid_domain");
 
   if (type == "@")
     return new ElemHideException(text, domain, selector);
 
-  if (type == "?")
+  if ((type == "?") || (type == "^"))
   {
     // Element hiding emulation filters are inefficient so we need to make sure
     // that they're only applied if they specify active domains
     if (!/,[^~][^,.]*\.[^,]/.test("," + domain))
       return new InvalidFilter(text, "filter_elemhideemulation_nodomain");
 
+    if (type == "^")
+      return new ElemHideEmulationException(text, domain, selector);
+
     return new ElemHideEmulationFilter(text, domain, selector);
   }
 
   return new ElemHideFilter(text, domain, selector);
 };
 
 /**
+ * Base class for element hiding exceptions
+ * @param {string} text see Filter()
+ * @param {string} domains  see ElemHideBase()
+ * @param {string} selector see ElemHideBase()
+ * @constructor
+ * @augments ElemHideBase
+ */
+function ElemHideExceptionBase(text, domains, selector)
+{
+  ElemHideBase.call(this, text, domains, selector);
+}
+exports.ElemHideExceptionBase = ElemHideExceptionBase;
+
+ElemHideExceptionBase.prototype = extend(ElemHideBase, {
+});
+
+/**
  * Class for element hiding filters
  * @param {string} text see Filter()
  * @param {string} domains  see ElemHideBase()
  * @param {string} selector see ElemHideBase()
  * @constructor
  * @augments ElemHideBase
  */
 function ElemHideFilter(text, domains, selector)
@@ -993,25 +1013,25 @@
 });
 
 /**
  * Class for element hiding exceptions
  * @param {string} text see Filter()
  * @param {string} domains  see ElemHideBase()
  * @param {string} selector see ElemHideBase()
  * @constructor
- * @augments ElemHideBase
+ * @augments ElemHideExceptionBase
  */
 function ElemHideException(text, domains, selector)
 {
-  ElemHideBase.call(this, text, domains, selector);
+  ElemHideExceptionBase.call(this, text, domains, selector);
 }
 exports.ElemHideException = ElemHideException;
 
-ElemHideException.prototype = extend(ElemHideBase, {
+ElemHideException.prototype = extend(ElemHideExceptionBase, {
   type: "elemhideexception"
 });
 
 /**
  * Class for element hiding emulation filters
  * @param {string} text           see Filter()
  * @param {string} domains        see ElemHideBase()
  * @param {string} selector       see ElemHideBase()
@@ -1022,8 +1042,26 @@
 {
   ElemHideBase.call(this, text, domains, selector);
 }
 exports.ElemHideEmulationFilter = ElemHideEmulationFilter;
 
 ElemHideEmulationFilter.prototype = extend(ElemHideBase, {
   type: "elemhideemulation"
 });
+
+/**
+ * Class for element hiding emulation exceptions
+ * @param {string} text see Filter()
+ * @param {string} domains  see ElemHideBase()
+ * @param {string} selector see ElemHideBase()
+ * @constructor
+ * @augments ElemHideExceptionBase
+ */
+function ElemHideEmulationException(text, domains, selector)
+{
+  ElemHideExceptionBase.call(this, text, domains, selector);
+}
+exports.ElemHideEmulationException = ElemHideEmulationException;
+
+ElemHideEmulationException.prototype = extend(ElemHideExceptionBase, {
+  type: "elemhideemulationexception"
+});