Issue 7452 - Do not cache element hiding filter objects by default

test/elemHide.js

Index: test/elemHide.js
===================================================================
--- a/test/elemHide.js
+++ b/test/elemHide.js
@@ -19,29 +19,29 @@
 
 const {createSandbox} = require("./_common");
 
 let ElemHide = null;
 let createStyleSheet = null;
 let rulesFromStyleSheet = null;
 let ElemHideExceptions = null;
 let Filter = null;
-let filtersByDomain = null;
+let filterTextByDomain = null;
 let selectorGroupSize = null;
 
 exports.setUp = function(callback)
 {
   let sandboxedRequire = createSandbox({
     extraExports: {
-      elemHide: ["filtersByDomain", "selectorGroupSize"]
+      elemHide: ["filterTextByDomain", "selectorGroupSize"]
     }
   });
   (
-    {ElemHide, createStyleSheet, rulesFromStyleSheet,
-     filtersByDomain, selectorGroupSize} = sandboxedRequire("../lib/elemHide"),
+    {ElemHide, createStyleSheet, rulesFromStyleSheet, filterTextByDomain,
+     selectorGroupSize} = sandboxedRequire("../lib/elemHide"),
     {ElemHideExceptions} = sandboxedRequire("../lib/elemHideExceptions"),
     {Filter} = sandboxedRequire("../lib/filterClasses")
   );
 
   callback();
 };
 
 function normalizeSelectors(selectors)
@@ -260,32 +260,32 @@
   ElemHideExceptions.add(Filter.fromText("foo.com#@#test"));
   testResult(test, "foo.com", []);
   testResult(test, "bar.com", ["test"]);
   test.done();
 };
 
 exports.testFiltersByDomain = function(test)
 {
-  test.equal(filtersByDomain.size, 0);
+  test.equal(filterTextByDomain.size, 0);
 
   ElemHide.add(Filter.fromText("##test"));
-  test.equal(filtersByDomain.size, 0);
+  test.equal(filterTextByDomain.size, 0);
 
   ElemHide.add(Filter.fromText("example.com##test"));
-  test.equal(filtersByDomain.size, 1);
+  test.equal(filterTextByDomain.size, 1);
 
   ElemHide.add(Filter.fromText("example.com,~www.example.com##test"));
-  test.equal(filtersByDomain.size, 2);
+  test.equal(filterTextByDomain.size, 2);
 
   ElemHide.remove(Filter.fromText("example.com##test"));
-  test.equal(filtersByDomain.size, 2);
+  test.equal(filterTextByDomain.size, 2);
 
   ElemHide.remove(Filter.fromText("example.com,~www.example.com##test"));
-  test.equal(filtersByDomain.size, 0);
+  test.equal(filterTextByDomain.size, 0);
 
   test.done();
 };
 
 exports.testCreateStyleSheet = function(test)
 {
   test.equal(
     createStyleSheet([