Issue 4125 - [emscripten] Convert filter classes to C++

compiled/Filter.cpp

 #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 "CSSPropertyFilter.h"
@@ skipping 37 matching lines @@
     // Remove trailing spaces
     for (; end > 0; end--)
       if (text[end - 1] != ' ')
         break;
 
     // Set new string boundaries
     text.reset(text, start, end - start);
   }
 }
 
-Filter::Filter(const String& text)
-    : mText(text)
+Filter::Filter(Type type, const String& text)
+    : mType(type), mText(text)
 {
   annotate_address(this, "Filter");
 }
 
 Filter::~Filter()
 {
-  // TODO: This should be removing from knownFilters
+  knownFilters.erase(mText);
 }
 
 OwnedString Filter::Serialize() const
 {
   OwnedString result(u"[Filter]\ntext="_str);
   result.append(mText);
   result.append(u'\n');
   return result;
 }
 
@@ skipping 13 matching lines @@
   DependentString error;
 
   Filter::Type type = CommentFilter::Parse(text);
   if (type == Filter::Type::UNKNOWN)
     type = ElemHideBase::Parse(text, data.elemhide);
   if (type == Filter::Type::UNKNOWN)
     type = RegExpFilter::Parse(text, error, data.regexp);
 
   auto knownFilter = knownFilters.find(text);
   if (knownFilter)
+  {
+    knownFilter->second->AddRef();
     return knownFilter->second;
+  }
 
   FilterPtr filter;
   switch (type)
   {
     case Filter::Type::COMMENT:
       filter = new CommentFilter(text);
       break;
     case Filter::Type::INVALID:
       filter = new InvalidFilter(text, error);
       break;
@@ skipping 19 matching lines @@
       return nullptr;
   }
 
   // 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.
   enter_context("Adding to known filters");
   knownFilter.assign(filter->mText, filter.get());
   exit_context();
 
-  // TODO: We intentionally leak the filter here - currently it won't be used
-  // for anything and would be deleted immediately.
-  filter->AddRef();
-
-  return filter;
+  return filter.release();
 }
-
-Filter* Filter::GetKnownFilter(const String& text)
-{
-  auto it = knownFilters.find(text);
-  if (it)
-    return it->second;
-  else
-    return nullptr;
-}