add test for triggered re-fetch

Author: shakyShane

special-pages/pages/new-tab/app/activity/ActivityProvider.js

@@ -241,18 +241,27 @@ export function SignalStateProvider({ children }) {
                 activity.value = normalizeItems(activity.value, evt.data);
             });
         });
-        // console.log('<--', document.visibilityState);
-        document.addEventListener('visibilitychange', () => {
+        const handler = () => {
             if (document.visibilityState === 'visible') {
+                console.log('will fetch');
                 service
                     .triggerDataFetch()
                     // eslint-disable-next-line promise/prefer-await-to-then
                     .catch((e) => console.error('trigger fetch errored', e));
             }
-        });
+        };
+
+        (() => {
+            // export the event in tests
+            if (window.__playwright_01) {
+                /** @type {any} */ (window).__trigger_document_visibilty__ = handler;
+            }
+        })();
+
+        document.addEventListener('visibilitychange', handler);
         return () => {
-            console.log('did cleanup');
             unsub();
+            document.removeEventListener('visibilitychange', handler);
         };
     });
 

special-pages/pages/new-tab/app/activity/integration-tests/activity.spec.js

@@ -92,4 +92,26 @@ test.describe('activity widget', () => {
         await ap.didRender();
         await ap.listsAtMost3TrackerCompanies();
     });
+    test('after rendering and navigating to a new tab, data is re-requested on return', async ({ page }, workerInfo) => {
+        const ntp = NewtabPage.create(page, workerInfo);
+        const ap = new ActivityPage(page, ntp);
+        await ntp.reducedMotion();
+        await ntp.openPage({ additional: { feed: 'activity' } });
+        await ap.didRender();
+
+        // Open a new tab and navigate it to about:blank
+        await ntp.mocks.waitForCallCount({ method: 'activity_getData', count: 1 });
+        const newTab = await page.context().newPage();
+        await newTab.goto('about:blank');
+
+        // Bring the first tab back into focus
+        await page.bringToFront();
+
+        await page.evaluate(() => {
+            // @ts-expect-error - testing only property
+            const fn = window.__trigger_document_visibilty__;
+            fn?.();
+        });
+        await ntp.mocks.waitForCallCount({ method: 'activity_getData', count: 2 });
+    });
 });