Fix hovercard view console error

closes #6480

Changelog.md

@@ -8,6 +8,7 @@
 * Normalize new followed tags and insert them alphabetically [#6454](https://github.com/diaspora/diaspora/pull/6454)
 * Add avatar fallback for notification dropdown [#6463](https://github.com/diaspora/diaspora/pull/6463)
 * Improve handling of j/k hotkeys [#6462](https://github.com/diaspora/diaspora/pull/6462)
+* Fix JS error caused by hovercards [6480](https://github.com/diaspora/diaspora/pull/6480)
 
 ## Features
 * Show spinner on initial stream load [#6384](https://github.com/diaspora/diaspora/pull/6384)

app/assets/javascripts/app/views/hovercard_view.js

@@ -147,6 +147,7 @@ app.views.Hovercard = app.views.Base.extend({
   },
 
   mouseIsOverElement: function(element, event) {
+    if(!element) { return false; }
     var elPos = element.offset();
     return event.pageX >= elPos.left &&
       event.pageX <= elPos.left + element.width() &&

spec/javascripts/app/views/hovercard_view_spec.js

+describe("app.views.Hovercard", function() {
+  beforeEach(function() {
+    this.view = new app.views.Hovercard();
+  });
+
+  describe("mouseIsOverElement", function() {
+    it("returns false if the element is undefined", function() {
+      expect(this.view.mouseIsOverElement(undefined, $.Event())).toBeFalsy();
+    });
+  });
+});