Issue 6862 - Add tests for Snippets module events

test/snippets.js

 /*
  * 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
@@ skipping 70 matching lines @@
     ],
     "other.example.com",
     ["foo-2"]
   );
 
   test.done();
 };
 
 exports.testSnippetFiltersContainer = function(test)
 {
+  let events = [];
+
+  function eventHandler(...args)
+  {
+    events.push([...args]);
+  }
+
   function compareRules(description, domain, expectedMatches)
   {
     let result = Snippets.getFiltersForDomain(domain);
     test.deepEqual(result.sort(), expectedMatches.sort(), description);
   }
 
+  Snippets.on("snippets.filterAdded",
+              eventHandler.bind(null, "snippets.filterAdded"));
+  Snippets.on("snippets.filterRemoved",
+              eventHandler.bind(null, "snippets.filterRemoved"));
+  Snippets.on("snippets.filtersCleared",
+              eventHandler.bind(null, "snippets.filtersCleared"));
+
   let domainFilter = Filter.fromText("example.com#$#filter1");
   let subdomainFilter = Filter.fromText("www.example.com#$#filter2");
   let otherDomainFilter = Filter.fromText("other.example.com#$#filter3");
 
   Snippets.add(domainFilter);
   Snippets.add(subdomainFilter);
   Snippets.add(otherDomainFilter);
   compareRules(
     "Return all matching filters",
     "www.example.com",
     [domainFilter, subdomainFilter]
   );
 
   Snippets.remove(domainFilter);
   compareRules(
     "Return all matching filters after removing one",
     "www.example.com",
     [subdomainFilter]
   );
 
   Snippets.clear();
   compareRules(
     "Return no filters after clearing",
     "www.example.com",
     []
   );
 
+  test.deepEqual(events, [
+    ["snippets.filterAdded", domainFilter],
+    ["snippets.filterAdded", subdomainFilter],
+    ["snippets.filterAdded", otherDomainFilter],
+    ["snippets.filterRemoved", domainFilter],
+    ["snippets.filtersCleared"]
+  ],
+  "Event log");
+
   test.done();
 };
 
 exports.testScriptParsing = function(test)
 {
   function checkParsedScript(description, script, expectedTree)
   {
     let tree = parseScript(script);
     test.deepEqual(tree, expectedTree, description);
   }
@@ skipping 148 matching lines @@
   // between executions. In the example below, assertFoo does not find 456 but
   // it doesn't find 123 either. It's the initial value 0.
   new Function(
     compileScript("setFoo 456; assertFoo 0", [
       ...libraries, "let foo = 1; exports.setFoo = value => { foo = value; };"
     ])
   )();
 
   test.done();
 };