Issue 4329 - Add $generichide support

lib/abp2blocklist.js

Index: lib/abp2blocklist.js
===================================================================
--- a/lib/abp2blocklist.js
+++ b/lib/abp2blocklist.js
@@ -345,28 +345,48 @@
     newSelector.push('[id=', selector.substring(pos.start + 1, pos.end), ']');
     i = pos.end;
   }
   newSelector.push(selector.substring(i));
 
   return newSelector.join("");
 }
 
+function addCSSRules(rules, selectors, matchDomain)
+{
+  while (selectors.length)
+  {
+    let selector = selectors.splice(0, selectorLimit).join(", ");
+
+    // As of Safari 9.0 element IDs are matched as lowercase. We work around
+    // this by converting to the attribute format [id="elementID"]
+    selector = convertIDSelectorsToAttributeSelectors(selector);
+
+    rules.push({
+      trigger: {"url-filter": matchDomain,
+                "url-filter-is-case-sensitive": true},
+      action: {type: "css-display-none",
+               selector: selector}
+    });
+  }
+}
+
 let ContentBlockerList =
 /**
  * Create a new Adblock Plus filter to content blocker list converter
  *
  * @constructor
  */
 exports.ContentBlockerList = function ()
 {
   this.requestFilters = [];
   this.requestExceptions = [];
   this.elemhideFilters = [];
   this.elemhideExceptions =  [];
+  this.generichideExceptions = [];
   this.elemhideSelectorExceptions = new Map();
 };
 
 /**
  * Add Adblock Plus filter to be converted
  *
  * @param {Filter} filter Filter to convert
  */
@@ -381,18 +401,20 @@
   if (filter instanceof filterClasses.BlockingFilter)
     this.requestFilters.push(filter);
 
   if (filter instanceof filterClasses.WhitelistFilter)
   {
     if (filter.contentType & (typeMap.DOCUMENT | whitelistableRequestTypes))
       this.requestExceptions.push(filter);
 
-      if (filter.contentType & typeMap.ELEMHIDE)
-        this.elemhideExceptions.push(filter);
+    if (filter.contentType & typeMap.ELEMHIDE)
+      this.elemhideExceptions.push(filter);
+    else if (filter.contentType & typeMap.GENERICHIDE)
+      this.generichideExceptions.push(filter);
   }
 
   if (filter instanceof filterClasses.ElemHideFilter)
     this.elemhideFilters.push(filter);
 
   if (filter instanceof filterClasses.ElemHideException)
   {
     let domains = this.elemhideSelectorExceptions[filter.selector];
@@ -407,51 +429,50 @@
  * Generate content blocker list for all filters that were added
  *
  * @returns   {Filter}   filter    Filter to convert
  */
 ContentBlockerList.prototype.generateRules = function(filter)
 {
   let rules = [];
 
+  let genericSelectors = [];
   let groupedElemhideFilters = new Map();
+
   for (let filter of this.elemhideFilters)
   {
     let result = convertElemHideFilter(filter, this.elemhideSelectorExceptions);
     if (!result)
       continue;
 
     if (result.matchDomains.length == 0)
-      result.matchDomains = ["^https?://"];
-
-    for (let matchDomain of result.matchDomains)
+    {
+      genericSelectors.push(result.selector);
+    }
+    else
     {
-      let group = groupedElemhideFilters.get(matchDomain) || [];
-      group.push(result.selector);
-      groupedElemhideFilters.set(matchDomain, group);
+      for (let matchDomain of result.matchDomains)
+      {
+        let group = groupedElemhideFilters.get(matchDomain) || [];
+        group.push(result.selector);
+        groupedElemhideFilters.set(matchDomain, group);
+      }
     }
   }
 
+  addCSSRules(rules, genericSelectors, "^https?://");
+
+  // Right after the generic element hiding filters, add the exceptions that
+  // should apply only to those filters.
+  for (let filter of this.generichideExceptions)
+    convertFilterAddRules(rules, filter, "ignore-previous-rules", false);
+
   groupedElemhideFilters.forEach((selectors, matchDomain) =>
   {
-    while (selectors.length)
-    {
-      let selector = selectors.splice(0, selectorLimit).join(", ");
-
-      // As of Safari 9.0 element IDs are matched as lowercase. We work around
-      // this by converting to the attribute format [id="elementID"]
-      selector = convertIDSelectorsToAttributeSelectors(selector);
-
-      rules.push({
-        trigger: {"url-filter": matchDomain,
-                  "url-filter-is-case-sensitive": true},
-        action: {type: "css-display-none",
-                 selector: selector}
-      });
-    }
+    addCSSRules(rules, selectors, matchDomain);
   });
 
   for (let filter of this.elemhideExceptions)
     convertFilterAddRules(rules, filter, "ignore-previous-rules", false);
   for (let filter of this.requestFilters)
     convertFilterAddRules(rules, filter, "block", true);
   for (let filter of this.requestExceptions)
     convertFilterAddRules(rules, filter, "ignore-previous-rules", true);