Issue 5870 - Implement the new ElemHideEmulation filter type

compiled/filter/Filter.cpp

 /*
  * 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
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include "Filter.h"
 #include "CommentFilter.h"
 #include "InvalidFilter.h"
 #include "RegExpFilter.h"
 #include "BlockingFilter.h"
 #include "WhitelistFilter.h"
 #include "ElemHideBase.h"
 #include "ElemHideFilter.h"
 #include "ElemHideException.h"
 #include "ElemHideEmulationFilter.h"
 #include "../StringMap.h"
+
+ABP_NS_USING
 
 namespace
 {
   StringMap<Filter*> knownFilters(8192);
 
   void NormalizeWhitespace(DependentString& text)
   {
     String::size_type start = 0;
     String::size_type end = text.length();
 
@@ skipping 32 matching lines @@
     text.reset(text, start, end - start);
   }
 }
 
 Filter::Filter(Type type, const String& text)
     : mText(text), mType(type)
 {
   annotate_address(this, "Filter");
 }
 
-Filter::Filter(Type type, String&& text)
-    : mText(text), mType(type)
-{
-  annotate_address(this, "Filter");
-}
-
 Filter::~Filter()
 {
   knownFilters.erase(mText);
 }
 
 OwnedString Filter::Serialize() const
 {
   OwnedString result(u"[Filter]\ntext="_str);
   result.append(mText);
   result.append(u'\n');
   return result;
 }
 
 Filter* Filter::FromText(DependentString& text)
 {
   NormalizeWhitespace(text);
   if (text.empty())
     return nullptr;
 
   // Parsing also normalizes the filter text, so it has to be done before the
   // lookup in knownFilters.
   union
   {
     RegExpFilterData regexp;
     ElemHideData elemhide;
   } data;
+  bool needConversion = false;
   DependentString error;
 
   Filter::Type type = CommentFilter::Parse(text);
   if (type == Filter::Type::UNKNOWN)
-    type = ElemHideBase::Parse(text, data.elemhide);
+    type = ElemHideBase::Parse(text, data.elemhide, needConversion);
   if (type == Filter::Type::UNKNOWN)
     type = RegExpFilter::Parse(text, error, data.regexp);
+
+  if (needConversion)
+    text = ElemHideBase::ConvertFilter(text, data.elemhide.mSelectorStart);
+
+  // At that point we failed the conversion.
+  if (text.empty())
+    return nullptr;
 
   auto knownFilter = knownFilters.find(text);
   if (knownFilter)
   {
     knownFilter->second->AddRef();
     return knownFilter->second;
   }
 
   FilterPtr filter;
   switch (type)
@@ skipping 31 matching lines @@
     knownFilters[filter->mText] = filter.get();
   else
     // This is a hack: we looked up the entry using text but create it using
     // filter->mText. This works because both are equal at this point. However,
     // text refers to a temporary buffer which will go away.
     knownFilter.assign(filter->mText, filter.get());
   exit_context();
 
   return filter.release();
 }