1 files changed, 53 insertions, 0 deletions
diff --git a/toolkit/jetpack/sdk/util/rules.js b/toolkit/jetpack/sdk/util/rules.js
new file mode 100644
index 000000000..98e3109b0
--- /dev/null
+++ b/toolkit/jetpack/sdk/util/rules.js
@@ -0,0 +1,53 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+module.metadata = {
+  "stability": "unstable"
+};
+
+const { Class } = require('../core/heritage');
+const { MatchPattern } = require('./match-pattern');
+const { emit } = require('../event/core');
+const { EventTarget } = require('../event/target');
+const { List, addListItem, removeListItem } = require('./list');
+
+// Should deprecate usage of EventEmitter/compose
+const Rules = Class({
+  implements: [
+    EventTarget,
+    List
+  ],
+  add: function(...rules) {
+    return [].concat(rules).forEach(function onAdd(rule) {
+      addListItem(this, rule);
+      emit(this, 'add', rule);
+    }, this);
+  },
+  remove: function(...rules) {
+    return [].concat(rules).forEach(function onRemove(rule) {
+      removeListItem(this, rule);
+      emit(this, 'remove', rule);
+    }, this);
+  },
+  get: function(rule) {
+    let found = false;
+    for (let i in this) if (this[i] === rule) found = true;
+    return found;
+  },
+  // Returns true if uri matches atleast one stored rule
+  matchesAny: function(uri) {
+    return !!filterMatches(this, uri).length;
+  },
+  toString: () => '[object Rules]'
+});
+exports.Rules = Rules;
+
+function filterMatches(instance, uri) {
+  let matches = [];
+  for (let i in instance) {
+    if (new MatchPattern(instance[i]).test(uri)) matches.push(instance[i]);
+  }
+  return matches;
+}