Add jest to start doing some tests

.eslintrc.json

@@ -1,8 +1,9 @@
 {
   "env": {
-    "node": true
+    "node": true,
+    "jest": true
   },
-  "extends": ["airbnb-base", "plugin:prettier/recommended"],
+  "extends": ["airbnb-base", "plugin:prettier/recommended", "plugin:jest/recommended"],
   "parserOptions": {
     "ecmaVersion": 2018
   },

README.md

@@ -10,6 +10,7 @@ It comes with many built-in features, such as authentication using JWT, request
 - [Express](http://expressjs.com)
 - [MongoDB](https://www.mongodb.com) object data modeling using [Mongoose](https://mongoosejs.com)
 - Authentication using [passport](http://www.passportjs.org) and role-based authorization
+- Unit and integration tests using [Jest](https://jestjs.io/)
 - Request data validation using [Joi](https://github.com/hapijs/joi)
 - Advanced production process management using [PM2](https://pm2.keymetrics.io)
 - Dependency management with [Yarn](https://yarnpkg.com)

jest.config.js

@@ -0,0 +1,4 @@
+module.exports = {
+  testEnvironment: 'node',
+  restoreMocks: true,
+};

package.json

@@ -11,6 +11,8 @@
   "scripts": {
     "start": "pm2 start ecosystem.config.json --no-daemon",
     "dev": "cross-env NODE_ENV=development nodemon src/index.js",
+    "test": "cross-env NODE_ENV=test jest tests -i",
+    "test:watch": "cross-env NODE_ENV=test jest tests -i --watchAll",
     "lint": "eslint .",
     "lint:fix": "eslint . --fix",
     "prettier": "prettier --check **/*.js",
@@ -39,8 +41,10 @@
     "eslint-config-airbnb-base": "^14.0.0",
     "eslint-config-prettier": "^6.4.0",
     "eslint-plugin-import": "^2.18.2",
+    "eslint-plugin-jest": "^23.0.2",
     "eslint-plugin-prettier": "^3.1.1",
     "husky": "^3.0.9",
+    "jest": "^24.9.0",
     "lint-staged": "^9.4.2",
     "nodemon": "^1.19.4",
     "prettier": "^1.18.2"

tests/integration/auth.test.js

@@ -0,0 +1,3 @@
+test('default test', () => {
+  expect(1 + 2).toBe(3);
+});