fix: support node and other non-browser environments

kumarharsh · May 15, 2018 · ddf42a6 · ddf42a6
1 parent 9935c2f
commit ddf42a6
Showing 1 changed file with 45 additions and 39 deletions.
diff --git a/custom-event-polyfill.js b/custom-event-polyfill.js
@@ -4,46 +4,52 @@
 // https://github.com/d4tocchini/customevent-polyfill
 // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent#Polyfill
 
-try {
-  var ce = new window.CustomEvent('test', { cancelable: true });
-  ce.preventDefault();
-  if (ce.defaultPrevented !== true) {
-    // IE has problems with .preventDefault() on custom events
-    // http://stackoverflow.com/questions/23349191
-    throw new Error('Could not prevent default');
+(function() {
+  if (!window) {
+    return;
   }
-} catch (e) {
-  var CustomEvent = function(event, params) {
-    var evt, origPrevent;
-    params = params || {
-      bubbles: false,
-      cancelable: false,
-      detail: undefined
-    };
 
-    evt = document.createEvent('CustomEvent');
-    evt.initCustomEvent(
-      event,
-      params.bubbles,
-      params.cancelable,
-      params.detail
-    );
-    origPrevent = evt.preventDefault;
-    evt.preventDefault = function() {
-      origPrevent.call(this);
-      try {
-        Object.defineProperty(this, 'defaultPrevented', {
-          get: function() {
-            return true;
-          }
-        });
-      } catch (e) {
-        this.defaultPrevented = true;
-      }
+  try {
+    var ce = new window.CustomEvent('test', { cancelable: true });
+    ce.preventDefault();
+    if (ce.defaultPrevented !== true) {
+      // IE has problems with .preventDefault() on custom events
+      // http://stackoverflow.com/questions/23349191
+      throw new Error('Could not prevent default');
+    }
+  } catch (e) {
+    var CustomEvent = function(event, params) {
+      var evt, origPrevent;
+      params = params || {
+        bubbles: false,
+        cancelable: false,
+        detail: undefined
+      };
+
+      evt = document.createEvent('CustomEvent');
+      evt.initCustomEvent(
+        event,
+        params.bubbles,
+        params.cancelable,
+        params.detail
+      );
+      origPrevent = evt.preventDefault;
+      evt.preventDefault = function() {
+        origPrevent.call(this);
+        try {
+          Object.defineProperty(this, 'defaultPrevented', {
+            get: function() {
+              return true;
+            }
+          });
+        } catch (e) {
+          this.defaultPrevented = true;
+        }
+      };
+      return evt;
     };
-    return evt;
-  };
 
-  CustomEvent.prototype = window.Event.prototype;
-  window.CustomEvent = CustomEvent; // expose definition to window
-}
+    CustomEvent.prototype = window.Event.prototype;
+    window.CustomEvent = CustomEvent; // expose definition to window
+  }
+})();