Feature testing jest

.babelrc

@@ -0,0 +1,9 @@
+{
+  "env": {
+    "test": {
+      "plugins": [
+        "@babel/plugin-transform-modules-commonjs"
+      ]
+    }
+  }
+}

.eslintrc.js

@@ -11,5 +11,6 @@ module.exports = {
         "sourceType": "module"
     },
     "rules": {
-    }
+    },
+    "ignorePatterns": ['dist/', 'node_modules/']
 };

.gitignore

@@ -1,3 +1,4 @@
 node_modules/
 hint-report/
-dist/
+dist/
+coverage/

.stylelintignore

@@ -0,0 +1 @@
+coverage/

__mocks__/localstorage.js

@@ -0,0 +1,13 @@
+export default class LocalStorage {
+  constructor() {
+    this.localStorage = [];
+  }
+
+  getItems() {
+    return this.localStorage;
+  }
+
+  setItems(value) {
+    this.localStorage.push(value);
+  }
+}

__test__/task-manipulation.mod.test.js

@@ -0,0 +1,52 @@
+/* eslint-disable no-undef */
+import { TaskManipulation } from "../src/modules/task-manipulation.mod";
+import LocalStorage from "../__mocks__/localstorage.js";
+import { renderWithEventListeners } from "../src/modules/task.mod";
+
+// Mock local storage
+let testTasks = new LocalStorage();
+let index = 0;
+let task = class {
+  constructor(desc) {
+    this.index = index++;
+    this.description = desc;
+    this.checked = false;
+  }
+};
+
+for (let i = 0; i < 3; i++) {
+  testTasks.setItems(new task("Task " + i));
+}
+
+beforeAll(() => {
+  document.body.innerHTML = `<ul id="task-list" class="flex flex-column w-100"></ul>`;
+  renderWithEventListeners(testTasks.getItems());
+});
+
+describe("TaskManipulation", () => {
+  describe("removeTask", () => {
+    test("remove a task from the list", () => {
+      TaskManipulation.removeTask(0, testTasks.getItems());
+      expect(testTasks.getItems().length).toBe(2);
+    });
+
+    test("removes li element from the list", () => {
+      renderWithEventListeners(testTasks.getItems());
+      const list = document.getElementById("task-list").childNodes.length;
+      expect(list).toBe(2);
+    });
+  });
+
+  describe("addTask", () => {
+    test("add a task to the list", () => {
+      TaskManipulation.addTask("Task New", testTasks.getItems());
+      expect(testTasks.getItems().length).toBe(3);
+    });
+
+    test("adds li element to the list", () => {
+      renderWithEventListeners(testTasks.getItems());
+      const list = document.getElementById("task-list").childNodes.length;
+      expect(list).toBe(3);
+    });
+  });
+});