ADD: Cypress & Testing Library;

Installing and configuring Cypress and its dependencies

Author: Davicho-Dev

cypress.json

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+{
+	"component": {
+		"testFiles": "**/*.test.{js,ts,jsx,tsx}",
+		"componentFolder": "src"
+	}
+}

cypress/fixtures/example.json

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+{
+	"name": "Using fixtures to represent data",
+	"email": "[email protected]",
+	"body": "Fixtures are a great way to mock data for responses to routes"
+}

cypress/integration/1-getting-started/todo.spec.js

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+/// <reference types="cypress" />
+
+// Welcome to Cypress!
+//
+// This spec file contains a variety of sample tests
+// for a todo list app that are designed to demonstrate
+// the power of writing tests in Cypress.
+//
+// To learn more about how Cypress works and
+// what makes it such an awesome testing tool,
+// please read our getting started guide:
+// https://on.cypress.io/introduction-to-cypress
+
+describe('example to-do app', () => {
+	beforeEach(() => {
+		// Cypress starts out with a blank slate for each test
+		// so we must tell it to visit our website with the `cy.visit()` command.
+		// Since we want to visit the same URL at the start of all our tests,
+		// we include it in our beforeEach function so that it runs before each test
+		cy.visit('https://example.cypress.io/todo')
+	})
+
+	it('displays two todo items by default', () => {
+		// We use the `cy.get()` command to get all elements that match the selector.
+		// Then, we use `should` to assert that there are two matched items,
+		// which are the two default items.
+		cy.get('.todo-list li').should('have.length', 2)
+
+		// We can go even further and check that the default todos each contain
+		// the correct text. We use the `first` and `last` functions
+		// to get just the first and last matched elements individually,
+		// and then perform an assertion with `should`.
+		cy.get('.todo-list li').first().should('have.text', 'Pay electric bill')
+		cy.get('.todo-list li').last().should('have.text', 'Walk the dog')
+	})
+
+	it('can add new todo items', () => {
+		// We'll store our item text in a variable so we can reuse it
+		const newItem = 'Feed the cat'
+
+		// Let's get the input element and use the `type` command to
+		// input our new list item. After typing the content of our item,
+		// we need to type the enter key as well in order to submit the input.
+		// This input has a data-test attribute so we'll use that to select the
+		// element in accordance with best practices:
+		// https://on.cypress.io/selecting-elements
+		cy.get('[data-test=new-todo]').type(`${newItem}{enter}`)
+
+		// Now that we've typed our new item, let's check that it actually was added to the list.
+		// Since it's the newest item, it should exist as the last element in the list.
+		// In addition, with the two default items, we should have a total of 3 elements in the list.
+		// Since assertions yield the element that was asserted on,
+		// we can chain both of these assertions together into a single statement.
+		cy.get('.todo-list li').should('have.length', 3).last().should('have.text', newItem)
+	})
+
+	it('can check off an item as completed', () => {
+		// In addition to using the `get` command to get an element by selector,
+		// we can also use the `contains` command to get an element by its contents.
+		// However, this will yield the <label>, which is lowest-level element that contains the text.
+		// In order to check the item, we'll find the <input> element for this <label>
+		// by traversing up the dom to the parent element. From there, we can `find`
+		// the child checkbox <input> element and use the `check` command to check it.
+		cy.contains('Pay electric bill').parent().find('input[type=checkbox]').check()
+
+		// Now that we've checked the button, we can go ahead and make sure
+		// that the list element is now marked as completed.
+		// Again we'll use `contains` to find the <label> element and then use the `parents` command
+		// to traverse multiple levels up the dom until we find the corresponding <li> element.
+		// Once we get that element, we can assert that it has the completed class.
+		cy.contains('Pay electric bill').parents('li').should('have.class', 'completed')
+	})
+
+	context('with a checked task', () => {
+		beforeEach(() => {
+			// We'll take the command we used above to check off an element
+			// Since we want to perform multiple tests that start with checking
+			// one element, we put it in the beforeEach hook
+			// so that it runs at the start of every test.
+			cy.contains('Pay electric bill').parent().find('input[type=checkbox]').check()
+		})
+
+		it('can filter for uncompleted tasks', () => {
+			// We'll click on the "active" button in order to
+			// display only incomplete items
+			cy.contains('Active').click()
+
+			// After filtering, we can assert that there is only the one
+			// incomplete item in the list.
+			cy.get('.todo-list li').should('have.length', 1).first().should('have.text', 'Walk the dog')
+
+			// For good measure, let's also assert that the task we checked off
+			// does not exist on the page.
+			cy.contains('Pay electric bill').should('not.exist')
+		})
+
+		it('can filter for completed tasks', () => {
+			// We can perform similar steps as the test above to ensure
+			// that only completed tasks are shown
+			cy.contains('Completed').click()
+
+			cy.get('.todo-list li')
+				.should('have.length', 1)
+				.first()
+				.should('have.text', 'Pay electric bill')
+
+			cy.contains('Walk the dog').should('not.exist')
+		})
+
+		it('can delete all completed tasks', () => {
+			// First, let's click the "Clear completed" button
+			// `contains` is actually serving two purposes here.
+			// First, it's ensuring that the button exists within the dom.
+			// This button only appears when at least one task is checked
+			// so this command is implicitly verifying that it does exist.
+			// Second, it selects the button so we can click it.
+			cy.contains('Clear completed').click()
+
+			// Then we can make sure that there is only one element
+			// in the list and our element does not exist
+			cy.get('.todo-list li').should('have.length', 1).should('not.have.text', 'Pay electric bill')
+
+			// Finally, make sure that the clear button no longer exists.
+			cy.contains('Clear completed').should('not.exist')
+		})
+	})
+})