Building Robust Applications with Nuxt.js and Testing Its Components

Getting Started with Nuxt.js

To create a new Nuxt.js application, navigate to your project folder and run the following command in your terminal:

npx create-nuxt-app <project-name>

This will take you through a series of options, including selecting Vuetify as your UI framework and Jest as your testing framework.

Configuring the Store

Nuxt.js leverages Vuex to efficiently manage states. Every file created in the /store directory can be treated as a Vuex module, containing its state, mutation, action, and getters. Let’s create a new games.js file in the /store directory and define our game store data.

export default {
  state: {
    games: []
  },
  mutations: {
    setGames(state, games) {
      state.games = games
    }
  },
  actions: {
    async fetchGames({ commit }) {
      const games = await fetchGamesFromApi()
      commit('setGames', games)
    }
  },
  getters: {
    getGames(state) {
      return state.games
    }
  }
}

Displaying Game Data

To display our game data on the main page, we’ll use the v-for directive to iterate through each item. We’ll also use Vuex’s MapGetter helper to map the previously defined getter in games.js to a computed property in our index.vue file.

<template>
  <div>
    <ul>
      <li v-for="game in games" :key="game.id">{{ game.name }}</li>
    </ul>
  </div>
</template>

<script>
import { mapGetters } from 'vuex'

export default {
  computed: {
   ...mapGetters(['getGames'])
  }
}
</script>

Configuring Jest for Testing

For our application’s testing framework, we’ll use Jest, which we selected during setup. We’ll configure Jest to use its globalSetup module, which exports an async function that is triggered once before all tests are run. This allows us to choose which particular store we want to test.

module.exports = async () => {
  await import('./store')
}

Writing Tests for Our Store

Let’s create a new games.test.js file inside the /test directory and write our tests. We’ll use Jest’s beforeAll block to import the built store and beforeEach block to ensure a new store is created each time a separate test is run.

import { shallowMount } from '@vue/test-utils'
import store from '../store'

beforeAll(async () => {
  await store.dispatch('fetchGames')
})

beforeEach(() => {
  store.state.games = []
})

it('should fetch games', async () => {
  expect(store.state.games.length).toBeGreaterThan(0)
})

Keeping Tests Simple and Concise

Writing tests for universal applications can be challenging, but a general rule of thumb is to always keep tests simple and concise. By following this approach, we can ensure our tests are efficient and effective.

• Avoid complex logic in your tests
• Focus on testing individual components
• Use mocking libraries to isolate dependencies