File size: 8,268 Bytes
1e92f2d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
---
title: How to set up Cypress with Next.js
nav_title: Cypress
description: Learn how to set up Cypress with Next.js for End-to-End (E2E) and Component Testing.
---

[Cypress](https://www.cypress.io/) is a test runner used for **End-to-End (E2E)** and **Component Testing**. This page will show you how to set up Cypress with Next.js and write your first tests.

> **Warning:**
>
> - Cypress versions below 13.6.3 do not support [TypeScript version 5](https://github.com/cypress-io/cypress/issues/27731) with `moduleResolution:"bundler"`. However, this issue has been resolved in Cypress version 13.6.3 and later. [cypress v13.6.3](https://docs.cypress.io/guides/references/changelog#13-6-3)

<AppOnly>

## Quickstart

You can use `create-next-app` with the [with-cypress example](https://github.com/vercel/next.js/tree/canary/examples/with-cypress) to quickly get started.

```bash filename="Terminal"
npx create-next-app@latest --example with-cypress with-cypress-app
```

</AppOnly>

## Manual setup

To manually set up Cypress, install `cypress` as a dev dependency:

```bash filename="Terminal"
npm install -D cypress
# or
yarn add -D cypress
# or
pnpm install -D cypress
```

Add the Cypress `open` command to the `package.json` scripts field:

```json filename="package.json"
{
  "scripts": {
    "dev": "next dev",
    "build": "next build",
    "start": "next start",
    "lint": "next lint",
    "cypress:open": "cypress open"
  }
}
```

Run Cypress for the first time to open the Cypress testing suite:

```bash filename="Terminal"
npm run cypress:open
```

You can choose to configure **E2E Testing** and/or **Component Testing**. Selecting any of these options will automatically create a `cypress.config.js` file and a `cypress` folder in your project.

## Creating your first Cypress E2E test

Ensure your `cypress.config` file has the following configuration:

```ts filename="cypress.config.ts" switcher
import { defineConfig } from 'cypress'

export default defineConfig({
  e2e: {
    setupNodeEvents(on, config) {},
  },
})
```

```js filename="cypress.config.js" switcher
const { defineConfig } = require('cypress')

module.exports = defineConfig({
  e2e: {
    setupNodeEvents(on, config) {},
  },
})
```

Then, create two new Next.js files:

<AppOnly>

```jsx filename="app/page.js"
import Link from 'next/link'

export default function Page() {
  return (
    <div>
      <h1>Home</h1>
      <Link href="/about">About</Link>
    </div>
  )
}
```

```jsx filename="app/about/page.js"
import Link from 'next/link'

export default function Page() {
  return (
    <div>
      <h1>About</h1>
      <Link href="/">Home</Link>
    </div>
  )
}
```

</AppOnly>

<PagesOnly>

```jsx filename="pages/index.js"
import Link from 'next/link'

export default function Home() {
  return (
    <div>
      <h1>Home</h1>
      <Link href="/about">About</Link>
    </div>
  )
}
```

```jsx filename="pages/about.js"
import Link from 'next/link'

export default function About() {
  return (
    <div>
      <h1>About</h1>
      <Link href="/">Home</Link>
    </div>
  )
}
```

</PagesOnly>

Add a test to check your navigation is working correctly:

```js filename="cypress/e2e/app.cy.js"
describe('Navigation', () => {
  it('should navigate to the about page', () => {
    // Start from the index page
    cy.visit('http://localhost:3000/')

    // Find a link with an href attribute containing "about" and click it
    cy.get('a[href*="about"]').click()

    // The new url should include "/about"
    cy.url().should('include', '/about')

    // The new page should contain an h1 with "About"
    cy.get('h1').contains('About')
  })
})
```

### Running E2E Tests

Cypress will simulate a user navigating your application, this requires your Next.js server to be running. We recommend running your tests against your production code to more closely resemble how your application will behave.

Run `npm run build && npm run start` to build your Next.js application, then run `npm run cypress:open` in another terminal window to start Cypress and run your E2E Testing suite.

> **Good to know:**
>
> - You can use `cy.visit("/")` instead of `cy.visit("http://localhost:3000/")` by adding `baseUrl: 'http://localhost:3000'` to the `cypress.config.js` configuration file.
> - Alternatively, you can install the [`start-server-and-test`](https://www.npmjs.com/package/start-server-and-test) package to run the Next.js production server in conjunction with Cypress. After installation, add `"test": "start-server-and-test start http://localhost:3000 cypress"` to your `package.json` scripts field. Remember to rebuild your application after new changes.

## Creating your first Cypress component test

Component tests build and mount a specific component without having to bundle your whole application or start a server.

Select **Component Testing** in the Cypress app, then select **Next.js** as your front-end framework. A `cypress/component` folder will be created in your project, and a `cypress.config.js` file will be updated to enable Component Testing.

Ensure your `cypress.config` file has the following configuration:

```ts filename="cypress.config.ts" switcher
import { defineConfig } from 'cypress'

export default defineConfig({
  component: {
    devServer: {
      framework: 'next',
      bundler: 'webpack',
    },
  },
})
```

```js filename="cypress.config.js" switcher
const { defineConfig } = require('cypress')

module.exports = defineConfig({
  component: {
    devServer: {
      framework: 'next',
      bundler: 'webpack',
    },
  },
})
```

Assuming the same components from the previous section, add a test to validate a component is rendering the expected output:

<AppOnly>

```tsx filename="cypress/component/about.cy.tsx"
import Page from '../../app/page'

describe('<Page />', () => {
  it('should render and display expected content', () => {
    // Mount the React component for the Home page
    cy.mount(<Page />)

    // The new page should contain an h1 with "Home"
    cy.get('h1').contains('Home')

    // Validate that a link with the expected URL is present
    // Following the link is better suited to an E2E test
    cy.get('a[href="/about"]').should('be.visible')
  })
})
```

</AppOnly>

<PagesOnly>

```jsx filename="cypress/component/about.cy.js"
import AboutPage from '../../pages/about'

describe('<AboutPage />', () => {
  it('should render and display expected content', () => {
    // Mount the React component for the About page
    cy.mount(<AboutPage />)

    // The new page should contain an h1 with "About page"
    cy.get('h1').contains('About')

    // Validate that a link with the expected URL is present
    // *Following* the link is better suited to an E2E test
    cy.get('a[href="/"]').should('be.visible')
  })
})
```

</PagesOnly>

> **Good to know**:
>
> - Cypress currently doesn't support Component Testing for `async` Server Components. We recommend using E2E testing.
> - Since component tests do not require a Next.js server, features like `<Image />` that rely on a server being available may not function out-of-the-box.

### Running Component Tests

Run `npm run cypress:open` in your terminal to start Cypress and run your Component Testing suite.

## Continuous Integration (CI)

In addition to interactive testing, you can also run Cypress headlessly using the `cypress run` command, which is better suited for CI environments:

```json filename="package.json"
{
  "scripts": {
    //...
    "e2e": "start-server-and-test dev http://localhost:3000 \"cypress open --e2e\"",
    "e2e:headless": "start-server-and-test dev http://localhost:3000 \"cypress run --e2e\"",
    "component": "cypress open --component",
    "component:headless": "cypress run --component"
  }
}
```

You can learn more about Cypress and Continuous Integration from these resources:

- [Next.js with Cypress example](https://github.com/vercel/next.js/tree/canary/examples/with-cypress)
- [Cypress Continuous Integration Docs](https://docs.cypress.io/guides/continuous-integration/introduction)
- [Cypress GitHub Actions Guide](https://on.cypress.io/github-actions)
- [Official Cypress GitHub Action](https://github.com/cypress-io/github-action)
- [Cypress Discord](https://discord.com/invite/cypress)