Test mutation + actions

jest.config.js

@@ -1,21 +1,18 @@
 module.exports = {
   moduleNameMapper: {
-    '^@/(.*)$': '<rootDir>/$1',
+    "^@/(.*)$": "<rootDir>/$1",
-    '^~/(.*)$': '<rootDir>/$1',
+    "^~/(.*)$": "<rootDir>/$1",
-    '^vue$': 'vue/dist/vue.common.js'
+    "^vue$": "vue/dist/vue.common.js"
   },
-  moduleFileExtensions: [
+  moduleFileExtensions: ["js", "vue", "json"],
-    'js',
-    'vue',
-    'json'
-  ],
   transform: {
-    '^.+\\.js$': 'babel-jest',
+    "^.+\\.js$": "babel-jest",
-    '.*\\.(vue)$': 'vue-jest'
+    ".*\\.(vue)$": "vue-jest"
   },
+  coverageDirectory: "<rootDir>/coverage",
   collectCoverage: true,
   collectCoverageFrom: [
-    '<rootDir>/components/**/*.vue',
+    "<rootDir>/components/**/*.vue",
-    '<rootDir>/pages/**/*.vue'
+    "<rootDir>/pages/**/*.vue"
   ]
-}
+};

pages/films/index.spec.js

@@ -1,37 +1,36 @@
-import { mount, shallowMount } from "@vue/test-utils";
+import { mount, shallowMount, createLocalVue } from "@vue/test-utils";
-import axios from "axios";
+import Vuex from "vuex";
-import FilmsView from "./";
+import Films from "./";
-import mockFilms from "@/test/fake-films.json";
 
-jest.mock("axios", () => ({
+const localVue = createLocalVue();
-  $get: jest.fn(() => mockFilms)
+localVue.use(Vuex);
-}));
 
 describe("Films page", () => {
+  let state, actions, store;
+
+  beforeEach(() => {
+    state = {
+      films: []
+    };
+    actions = {
+      getFilms: jest.fn()
+    };
+    store = new Vuex.Store({ state, actions });
+  });
+
   it("should render Films page instance", () => {
-    const wrapper = mount(FilmsView);
+    const wrapper = mount(Films, { store, localVue });
     expect(wrapper.find("img").exists()).toBe(true);
   });
 
   it("should get films from Ghibli API", async () => {
-    let wrapper = shallowMount(FilmsView, {
+    let wrapper = shallowMount(Films, {
-      mocks: {
+      store,
-        $axios: axios
+      localVue
-      }
-    });
-
-    expect((await wrapper.vm.$options.asyncData(wrapper.vm)).films).toEqual(
-      mockFilms
-    );
-
-    // Init page with mocked asyncData
-    wrapper = shallowMount(FilmsView, {
-      mocks: {
-        films: (await wrapper.vm.$options.asyncData(wrapper.vm)).films,
-        $axios: axios
-      }
     });
 
+    await wrapper.vm.$options.asyncData({ store });
+    expect(actions.getFilms).toHaveBeenCalled();
     expect(wrapper.findComponent({ name: "Grid" }).exists()).toBe(true);
   });
 });

store/index.js

@@ -10,8 +10,12 @@ export const mutations = {
 
 export const actions = {
   async getFilms({ commit }) {
+    try {
       const films = await this.$axios.$get("/api/films");
       commit("setFilms", films);
+    } catch (e) {
+      throw Error("API Error occurred.");
+    }
   }
 };
 

test/actions.spec.js

@@ -0,0 +1,35 @@
+import { actions, mutations } from "@/store";
+import axios from "axios";
+import mockFilms from "@/test/fake-films.json";
+
+let url = "";
+
+jest.mock("axios", () => ({
+  $get: _url => {
+    return new Promise(resolve => {
+      url = _url;
+      resolve(mockFilms);
+    });
+  }
+}));
+
+describe("Vuex actions.", () => {
+  it("tests getFilms action.", async () => {
+    const commit = jest.fn();
+
+    actions.$axios = axios;
+    await actions.getFilms({ commit });
+
+    expect(url).toBe("/api/films");
+    expect(commit).toHaveBeenCalledWith("setFilms", mockFilms);
+  });
+
+  it("catches errors.", async () => {
+    const commit = jest.fn();
+
+    actions.$axios = null;
+    await expect(actions.getFilms({ commit })).rejects.toThrow(
+      "API Error occurred."
+    );
+  });
+});

test/mutations.spec.js

@@ -0,0 +1,9 @@
+import { state, mutations } from "@/store";
+import mockFilms from "./fake-films.json";
+
+describe("Vuex mutations.", () => {
+  it("tests setFilms mutation.", () => {
+    mutations.setFilms(state, mockFilms);
+    expect(state.films[0].id).toBe(mockFilms[0].id);
+  });
+});