add cypress demo tests

cypress/integration/examples/local_storage.spec.js

@@ -0,0 +1,52 @@
+/// <reference types="Cypress" />
+
+context('Local Storage', () => {
+  beforeEach(() => {
+    cy.visit('https://example.cypress.io/commands/local-storage')
+  })
+  // Although local storage is automatically cleared
+  // in between tests to maintain a clean state
+  // sometimes we need to clear the local storage manually
+
+  it('cy.clearLocalStorage() - clear all data in local storage', () => {
+    // https://on.cypress.io/clearlocalstorage
+    cy.get('.ls-btn').click().should(() => {
+      expect(localStorage.getItem('prop1')).to.eq('red')
+      expect(localStorage.getItem('prop2')).to.eq('blue')
+      expect(localStorage.getItem('prop3')).to.eq('magenta')
+    })
+
+    // clearLocalStorage() yields the localStorage object
+    cy.clearLocalStorage().should((ls) => {
+      expect(ls.getItem('prop1')).to.be.null
+      expect(ls.getItem('prop2')).to.be.null
+      expect(ls.getItem('prop3')).to.be.null
+    })
+
+    // Clear key matching string in Local Storage
+    cy.get('.ls-btn').click().should(() => {
+      expect(localStorage.getItem('prop1')).to.eq('red')
+      expect(localStorage.getItem('prop2')).to.eq('blue')
+      expect(localStorage.getItem('prop3')).to.eq('magenta')
+    })
+
+    cy.clearLocalStorage('prop1').should((ls) => {
+      expect(ls.getItem('prop1')).to.be.null
+      expect(ls.getItem('prop2')).to.eq('blue')
+      expect(ls.getItem('prop3')).to.eq('magenta')
+    })
+
+    // Clear keys matching regex in Local Storage
+    cy.get('.ls-btn').click().should(() => {
+      expect(localStorage.getItem('prop1')).to.eq('red')
+      expect(localStorage.getItem('prop2')).to.eq('blue')
+      expect(localStorage.getItem('prop3')).to.eq('magenta')
+    })
+
+    cy.clearLocalStorage(/prop1|2/).should((ls) => {
+      expect(ls.getItem('prop1')).to.be.null
+      expect(ls.getItem('prop2')).to.be.null
+      expect(ls.getItem('prop3')).to.eq('magenta')
+    })
+  })
+})