Update grunt-contrib-qunit and extend FullScreen test

Update the package responsible for running tests, grunt-contrib-qunit.

The package change includes a significant bump to the puppeteer version used to run the tests (from v9 -> v19: https://github.com/gruntjs/grunt-contrib-qunit#release-history).

Running the tests with the newer puppeteer version leads to issues running the FullScreen test when run in the 'old'/current default headless mode (the test fails with a timeout).

Updating to the 'new' headless mode (eventually to be the default anyway), seems to allow the fullscreen request to succeed.

Thus, go ahead and extend the FullScreen test to verify the correct values for a successful request, as well as an additional step to exit fullscreen mode.

Gruntfile.js

@@ -161,8 +161,11 @@ module.exports = function(grunt) {
             normal: {
                 options: {
                     urls: [ "http://localhost:8000/test/test.html" ],
-                    timeout: 10000
+                    timeout: 10000,
-                }
+                    puppeteer: {
+                        headless: 'new'
+                    }
+                },
             },
             coverage: {
                 options: {

package.json

@@ -35,7 +35,7 @@
         "grunt-contrib-compress": "^2.0.0",
         "grunt-contrib-concat": "^2.1.0",
         "grunt-contrib-connect": "^3.0.0",
-        "grunt-contrib-qunit": "^6.2.0",
+        "grunt-contrib-qunit": "^7.0.1",
         "grunt-contrib-uglify": "^5.0.1",
         "grunt-contrib-watch": "^1.1.0",
         "grunt-eslint": "^24.0.1",
@@ -48,4 +48,4 @@
         "test": "grunt test",
         "prepare": "grunt build"
     }
-}
+}

test/modules/basic.js

@@ -231,25 +231,36 @@
             return;
         }
 
-        viewer.addHandler("open", function () {
+        viewer.addHandler('open', function () {
             assert.ok(!OpenSeadragon.isFullScreen(), 'Started out not fullscreen');
 
-            const checkEnteringPreFullScreen = function(event) {
+            const checkEnteringPreFullScreen = (event) => {
                 viewer.removeHandler('pre-full-screen', checkEnteringPreFullScreen);
                 assert.ok(event.fullScreen, 'Switching to fullscreen');
                 assert.ok(!OpenSeadragon.isFullScreen(), 'Not yet fullscreen');
             };
 
-            // The fullscreen mode is always denied during tests so we are
+            const checkExitingFullScreen = (event) => {
-            // exiting directly.
-            const checkExitingFullScreen = function(event) {
                 viewer.removeHandler('full-screen', checkExitingFullScreen);
-                assert.ok(!event.fullScreen, 'Exiting fullscreen');
+                assert.ok(!event.fullScreen, 'Disabling fullscreen');
-                assert.ok(!OpenSeadragon.isFullScreen(), 'Disabled fullscreen');
+                assert.ok(!OpenSeadragon.isFullScreen(), 'Fullscreen disabled');
                 done();
+            }
+
+            // The 'new' headless mode allows us to enter fullscreen, so verify
+            // that we see the correct values returned. We will then close out
+            // of fullscreen to check the same values when exiting.
+            const checkAcquiredFullScreen = (event) => {
+                viewer.removeHandler('full-screen', checkAcquiredFullScreen);
+                viewer.addHandler('full-screen', checkExitingFullScreen);
+                assert.ok(event.fullScreen, 'Acquired fullscreen');
+                assert.ok(OpenSeadragon.isFullScreen(), 'Fullscreen enabled');
+                viewer.setFullScreen(false);
             };
-            viewer.addHandler("pre-full-screen", checkEnteringPreFullScreen);
+
-            viewer.addHandler("full-screen", checkExitingFullScreen);
+
+            viewer.addHandler('pre-full-screen', checkEnteringPreFullScreen);
+            viewer.addHandler('full-screen', checkAcquiredFullScreen);
             viewer.setFullScreen(true);
         });