trying to uninstall all SW and clear caches

Author: bahmutov

cypress/integration/no-sw-spec.js

@@ -0,0 +1,42 @@
+/* eslint-env mocha */
+/* global cy, Cypress */
+describe('Without ServiceWorker', () => {
+  // cleaning anything cached by the ServiceWorker
+  // and preventing ServiceWorker from registering
+  // https://github.com/cypress-io/cypress/issues/702
+  const clearCache = (name) =>
+    window.caches.delete(name)
+
+  const clearCaches = () =>
+    window.caches.keys().then(cacheNames =>
+      Promise.all(cacheNames.map(clearCache)))
+
+  // prevents new service worker registration
+  const neverRegisterSW = (win) => {
+    // use a promise that never resolves
+    const neverResolves = new Promise(resolve => {})
+    win.navigator.serviceWorker.register = () => neverResolves
+  }
+
+  // unregisters any service workers already registered
+  const unregisterWorkers = (win) =>
+    win.navigator.serviceWorker.getRegistrations()
+    .then(registrations =>
+      Cypress.Promise.map(registrations, sw => sw.unregister())
+    )
+
+  beforeEach(clearCaches)
+
+  beforeEach(() => {
+    cy.visit('/', {
+      onBeforeLoad: win => {
+        neverRegisterSW(win)
+        return unregisterWorkers(win)
+      }
+    })
+  })
+
+  it('loads news items', () => {
+    cy.get('.news-item').should('have.length.gt', 10)
+  })
+})