diff -r 000000000000 -r 6474c204b198 addon-sdk/source/test/test-event-core.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/addon-sdk/source/test/test-event-core.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,245 @@
+/* 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';
+
+const { on, once, off, emit, count } = require('sdk/event/core');
+const { LoaderWithHookedConsole } = require("sdk/test/loader");
+
+exports['test add a listener'] = function(assert) {
+  let events = [ { name: 'event#1' }, 'event#2' ];
+  let target = { name: 'target' };
+
+  on(target, 'message', function(message) {
+    assert.equal(this, target, 'this is a target object');
+    assert.equal(message, events.shift(), 'message is emitted event');
+  });
+  emit(target, 'message', events[0]);
+  emit(target, 'message', events[0]);
+};
+
+exports['test that listener is unique per type'] = function(assert) {
+  let actual = []
+  let target = {}
+  function listener() { actual.push(1) }
+  on(target, 'message', listener);
+  on(target, 'message', listener);
+  on(target, 'message', listener);
+  on(target, 'foo', listener);
+  on(target, 'foo', listener);
+
+  emit(target, 'message');
+  assert.deepEqual([ 1 ], actual, 'only one message listener added');
+  emit(target, 'foo');
+  assert.deepEqual([ 1, 1 ], actual, 'same listener added for other event');
+};
+
+exports['test event type matters'] = function(assert) {
+  let target = { name: 'target' }
+  on(target, 'message', function() {
+    assert.fail('no event is expected');
+  });
+  on(target, 'done', function() {
+    assert.pass('event is emitted');
+  });
+  emit(target, 'foo')
+  emit(target, 'done');
+};
+
+exports['test all arguments are pasesd'] = function(assert) {
+  let foo = { name: 'foo' }, bar = 'bar';
+  let target = { name: 'target' };
+  on(target, 'message', function(a, b) {
+    assert.equal(a, foo, 'first argument passed');
+    assert.equal(b, bar, 'second argument passed');
+  });
+  emit(target, 'message', foo, bar);
+};
+
+exports['test no side-effects in emit'] = function(assert) {
+  let target = { name: 'target' };
+  on(target, 'message', function() {
+    assert.pass('first listener is called');
+    on(target, 'message', function() {
+      assert.fail('second listener is called');
+    });
+  });
+  emit(target, 'message');
+};
+
+exports['test can remove next listener'] = function(assert) {
+  let target = { name: 'target' };
+  function fail() assert.fail('Listener should be removed');
+
+  on(target, 'data', function() {
+    assert.pass('first litener called');
+    off(target, 'data', fail);
+  });
+  on(target, 'data', fail);
+
+  emit(target, 'data', 'hello');
+};
+
+exports['test order of propagation'] = function(assert) {
+  let actual = [];
+  let target = { name: 'target' };
+  on(target, 'message', function() { actual.push(1); });
+  on(target, 'message', function() { actual.push(2); });
+  on(target, 'message', function() { actual.push(3); });
+  emit(target, 'message');
+  assert.deepEqual([ 1, 2, 3 ], actual, 'called in order they were added');
+};
+
+exports['test remove a listener'] = function(assert) {
+  let target = { name: 'target' };
+  let actual = [];
+  on(target, 'message', function listener() {
+    actual.push(1);
+    on(target, 'message', function() {
+      off(target, 'message', listener);
+      actual.push(2);
+    })
+  });
+
+  emit(target, 'message');
+  assert.deepEqual([ 1 ], actual, 'first listener called');
+  emit(target, 'message');
+  assert.deepEqual([ 1, 1, 2 ], actual, 'second listener called');
+
+  emit(target, 'message');
+  assert.deepEqual([ 1, 1, 2, 2, 2 ], actual, 'first listener removed');
+};
+
+exports['test remove all listeners for type'] = function(assert) {
+  let actual = [];
+  let target = { name: 'target' }
+  on(target, 'message', function() { actual.push(1); });
+  on(target, 'message', function() { actual.push(2); });
+  on(target, 'message', function() { actual.push(3); });
+  on(target, 'bar', function() { actual.push('b') });
+  off(target, 'message');
+
+  emit(target, 'message');
+  emit(target, 'bar');
+
+  assert.deepEqual([ 'b' ], actual, 'all message listeners were removed');
+};
+
+exports['test remove all listeners'] = function(assert) {
+  let actual = [];
+  let target = { name: 'target' }
+  on(target, 'message', function() { actual.push(1); });
+  on(target, 'message', function() { actual.push(2); });
+  on(target, 'message', function() { actual.push(3); });
+  on(target, 'bar', function() { actual.push('b') });
+  off(target);
+
+  emit(target, 'message');
+  emit(target, 'bar');
+
+  assert.deepEqual([], actual, 'all listeners events were removed');
+};
+
+exports['test falsy arguments are fine'] = function(assert) {
+  let type, listener, actual = [];
+  let target = { name: 'target' }
+  on(target, 'bar', function() { actual.push(0) });
+
+  off(target, 'bar', listener);
+  emit(target, 'bar');
+  assert.deepEqual([ 0 ], actual, '3rd bad ard will keep listeners');
+
+  off(target, type);
+  emit(target, 'bar');
+  assert.deepEqual([ 0, 0 ], actual, '2nd bad arg will keep listener');
+
+  off(target, type, listener);
+  emit(target, 'bar');
+  assert.deepEqual([ 0, 0, 0 ], actual, '2nd&3rd bad args will keep listener');
+};
+
+exports['test error handling'] = function(assert) {
+  let target = Object.create(null);
+  let error = Error('boom!');
+
+  on(target, 'message', function() { throw error; })
+  on(target, 'error', function(boom) {
+    assert.equal(boom, error, 'thrown exception causes error event');
+  });
+  emit(target, 'message');
+};
+
+exports['test unhandled exceptions'] = function(assert) {
+  let exceptions = [];
+  let { loader, messages } = LoaderWithHookedConsole(module);
+
+  let { emit, on } = loader.require('sdk/event/core');
+  let target = {};
+  let boom = Error('Boom!');
+  let drax = Error('Draax!!');
+
+  on(target, 'message', function() { throw boom; });
+
+  emit(target, 'message');
+  assert.equal(messages.length, 1, 'Got the first exception');
+  assert.equal(messages[0].type, 'exception', 'The console message is exception');
+  assert.ok(~String(messages[0].msg).indexOf('Boom!'),
+            'unhandled exception is logged');
+
+  on(target, 'error', function() { throw drax; });
+  emit(target, 'message');
+  assert.equal(messages.length, 2, 'Got the second exception');
+  assert.equal(messages[1].type, 'exception', 'The console message is exception');
+  assert.ok(~String(messages[1].msg).indexOf('Draax!'),
+            'error in error handler is logged');
+};
+
+exports['test unhandled errors'] = function(assert) {
+  let exceptions = [];
+  let { loader, messages } = LoaderWithHookedConsole(module);
+
+  let { emit, on } = loader.require('sdk/event/core');
+  let target = {};
+  let boom = Error('Boom!');
+
+  emit(target, 'error', boom);
+  assert.equal(messages.length, 1, 'Error was logged');
+  assert.equal(messages[0].type, 'exception', 'The console message is exception');
+  assert.ok(~String(messages[0].msg).indexOf('Boom!'),
+            'unhandled exception is logged');
+};
+
+
+exports['test count'] = function(assert) {
+  let target = {};
+
+  assert.equal(count(target, 'foo'), 0, 'no listeners for "foo" events');
+  on(target, 'foo', function() {});
+  assert.equal(count(target, 'foo'), 1, 'listener registered');
+  on(target, 'foo', function() {}, 2, 'another listener registered');
+  off(target)
+  assert.equal(count(target, 'foo'), 0, 'listeners unregistered');
+};
+
+exports['test listen to all events'] = function(assert) {
+  let actual = [];
+  let target = {};
+
+  on(target, 'foo', message => actual.push(message));
+  on(target, '*', (type, ...message) => {
+    actual.push([type].concat(message));
+  });
+ 
+  emit(target, 'foo', 'hello');
+  assert.equal(actual[0], 'hello',
+    'non-wildcard listeners still work');
+  assert.deepEqual(actual[1], ['foo', 'hello'],
+    'wildcard listener called');
+
+  emit(target, 'bar', 'goodbye');
+  assert.deepEqual(actual[2], ['bar', 'goodbye'],
+    'wildcard listener called for unbound event name');
+};
+
+require('test').run(exports);