Merge pull request #140 from webcomponents/fix-139

Fixes #139

Author: Steve Orvell

shadydom.min.js

@@ -25,9 +25,13 @@ function getAssignedSlot(node) {
 
 let windowMixin = {
 
-  addEventListener: addEventListener,
+  // NOTE: ensure these methods are bound to `window` so that `this` is correct
+  // when called directly from global context without a receiver; e.g.
+  // `addEventListener(...)`.
+  addEventListener: addEventListener.bind(window),
+
+  removeEventListener: removeEventListener.bind(window)
 
-  removeEventListener: removeEventListener
 };
 
 let nodeMixin = {

shadydom.min.js.map

@@ -294,7 +294,7 @@ export function addEventListener(type, fnOrObj, optionsOrCapture) {
   // hack to let ShadyRoots have event listeners
   // event listener will be on host, but `currentTarget`
   // will be set to shadyroot for event listener
-  let target = optionsOrCapture && optionsOrCapture.__shadyTarget || this;
+  let target = (optionsOrCapture && optionsOrCapture.__shadyTarget) || this;
 
   if (fnOrObj.__eventWrappers) {
     // Stop if the wrapper function has already been created.
@@ -392,7 +392,7 @@ export function removeEventListener(type, fnOrObj, optionsOrCapture) {
     once = false;
     passive = false;
   }
-  let target = optionsOrCapture && optionsOrCapture.__shadyTarget || this;
+  let target = (optionsOrCapture && optionsOrCapture.__shadyTarget) || this;
   // Search the wrapped function.
   let wrapperFn = undefined;
   if (fnOrObj.__eventWrappers) {

src/patch-builtins.js

@@ -313,6 +313,20 @@
       el.parentNode.removeChild(el);
     });
 
+    test('implicit window add/remove event listener', function() {
+      var el = createEnabledElement('x-event-scoped-window');
+      var listener = function(e) {
+        el.windowListenerEvents = el.windowListenerEvents ? el.windowListenerEvents+1 : 1;
+      };
+      addEventListener("composed", listener);
+      el.fireComposed();
+      assert.equal(1, el.windowListenerEvents);
+      removeEventListener("composed", listener);
+      el.fireComposed();
+      assert.equal(1, el.windowListenerEvents);
+      el.parentNode.removeChild(el);
+    });
+
     test('scoped event does not reach window', function() {
       var el = createEnabledElement('x-event-scoped-window');
       el.fireScoped();