fix(modal): focus on body if element disappears

- Change to focus on `document.body` instead if element is not present

Closes #3653
Fixes #3639

Author: tompi

Diff for: src/modal/modal.js

@@ -195,7 +195,7 @@ angular.module('ui.bootstrap.modal', [])
         }
       });
 
-      function removeModalWindow(modalInstance) {
+      function removeModalWindow(modalInstance, elementToReceiveFocus) {
 
         var body = $document.find('body').eq(0);
         var modalWindow = openedWindows.get(modalInstance).value;
@@ -208,6 +208,13 @@ angular.module('ui.bootstrap.modal', [])
           body.toggleClass(OPENED_MODAL_CLASS, openedWindows.length() > 0);
           checkRemoveBackdrop();
         });
+
+        //move focus to specified element if available, or else to body
+        if (elementToReceiveFocus && elementToReceiveFocus.focus) {
+          elementToReceiveFocus.focus();
+        } else {
+          body.focus();
+        }
       }
 
       function checkRemoveBackdrop() {
@@ -318,8 +325,7 @@ angular.module('ui.bootstrap.modal', [])
         var modalWindow = openedWindows.get(modalInstance);
         if (modalWindow && broadcastClosing(modalWindow, result, true)) {
           modalWindow.value.deferred.resolve(result);
-          removeModalWindow(modalInstance);
-          modalWindow.value.modalOpener.focus();
+          removeModalWindow(modalInstance, modalWindow.value.modalOpener);
           return true;
         }
         return !modalWindow;
@@ -329,8 +335,7 @@ angular.module('ui.bootstrap.modal', [])
         var modalWindow = openedWindows.get(modalInstance);
         if (modalWindow && broadcastClosing(modalWindow, reason, false)) {
           modalWindow.value.deferred.reject(reason);
-          removeModalWindow(modalInstance);
-          modalWindow.value.modalOpener.focus();
+          removeModalWindow(modalInstance, modalWindow.value.modalOpener);
           return true;
         }
         return !modalWindow;

Diff for: src/modal/test/modal.spec.js

@@ -250,7 +250,7 @@ describe('$modal', function () {
       expect($document).toHaveModalsOpen(0);
     });
 
-    it('should return to the element which had focus before the dialog is invoked', function () {
+    it('should return to the element which had focus before the dialog was invoked', function () {
       var link = '<a href>Link</a>';
       var element = angular.element(link);
       angular.element(document.body).append(element);
@@ -272,6 +272,30 @@ describe('$modal', function () {
       element.remove();
     });
 
+    it('should return to document.body if element which had focus before the dialog was invoked is gone, or is missing focus function', function () {
+      var link = '<a href>Link</a>';
+      var element = angular.element(link);
+      angular.element(document.body).append(element);
+      element.focus();
+      expect(document.activeElement.tagName).toBe('A');
+
+      var modal = open({template: '<div>Content</div>'});
+      $timeout.flush();
+      expect(document.activeElement.tagName).toBe('DIV');
+      expect($document).toHaveModalsOpen(1);
+
+      // Fake undefined focus function, happening in IE in certain
+      // iframe conditions. See issue 3639
+      element[0].focus = undefined;
+      triggerKeyDown($document, 27);
+      $timeout.flush();
+      $rootScope.$digest();
+
+      expect(document.activeElement.tagName).toBe('BODY');
+      expect($document).toHaveModalsOpen(0);
+      element.remove();
+    });
+
     it('should resolve returned promise on close', function () {
       var modal = open({template: '<div>Content</div>'});
       close(modal, 'closed ok');