fix: show a notification even if building it fails

lib/__tests__/sw-push-delivery.test.ts

@@ -187,4 +187,26 @@ describe('which login a push is for', () => {
   });
 });
 
+describe('when building the notification goes wrong', () => {
+  it('still shows one', async () => {
+    const { push, shade } = loadWorker(() => ({ unreadTotal: 1, slot: 0, login: 'fp', email: mail('e1') }), {
+      globals: { Notification: { get maxActions() { throw new Error('no such thing'); } } },
+    });
+    await push(delivery('a', 'e1'));
+    expect(shade.size).toBe(1);
+  });
+
+  it('shows one for a push that is no JSON at all', async () => {
+    const { dispatch, shade } = loadWorker(() => null);
+    await dispatch('push', { data: { json: () => { throw new SyntaxError('not JSON'); } } });
+    expect(shade.size).toBe(1);
+  });
+
+  it('shows one for a push without any data', async () => {
+    const { dispatch, shade } = loadWorker(() => null);
+    await dispatch('push', {});
+    expect(shade.size).toBe(1);
+  });
+});
+
 // -- end of cases --

public/sw.js

@@ -604,7 +604,19 @@ async function handlePush(event) {
     ? []
     : Object.keys(changed).filter((id) => changed[id] && typeof changed[id] === "object" && "EmailDelivery" in changed[id]);
   for (const accountId of withNewMail.length > 0 ? withNewMail : [named]) {
-    await notifyAccount(accountId, emailIds, accountLabel);
+    try {
+      await notifyAccount(accountId, emailIds, accountLabel);
+    } catch (_) {
+      // Nothing above may cost the user the alert, or a browser its quota for
+      // this site: see showWithoutAlert.
+      await self.registration.showNotification(accountLabel ? `New mail (${accountLabel})` : "New mail", {
+        body: "You have new mail",
+        tag: "bulwark-mail:" + (accountId || "default"),
+        icon: `${BASE_PATH}/api/pwa-icon/192`,
+        badge: `${BASE_PATH}/api/pwa-icon/192`,
+        data: { kind: "mail-list", accountId },
+      });
+    }
   }
 }