feat: add tests

.mocharc.json

@@ -0,0 +1,7 @@
+{
+  "extension": [
+    "ts"
+  ],
+  "spec": "./**/*.spec.ts",
+  "require": "ts-node/register"
+}

README.md

@@ -10,3 +10,20 @@ An npm package for demonstration purposes using TypeScript to build for both the
 1. Create an account with [npm](https://www.npmjs.com/signup) if you don't have one already. Also be sure to enable [two-factor authentication](https://docs.npmjs.com/configuring-two-factor-authentication)
 1. Sign in to your npm account in your terminal with `npm login`
 1. Run `npm publish --access=public` to publish your package
+
+### Testing
+
+1. `npm i -D mocha @type/mocha chai @types/chai ts-node`
+1. Create a new file `.mocharc.json` in the root directory with the following contents:
+   ```json
+   {
+     "extension": ["ts"],
+     "spec": "./**/*.spec.ts",
+     "require": "ts-node/register"
+   }
+   ```
+1. Create a `tests` folder
+1. Create an `index.spec.ts` file in the `tests` folder
+1. Write unit tests in the `index.spec.ts` file to test the code in `index.ts`
+1. Add a `"test"` property in the `package.json` file and give it a value of `"mocha"`
+1. Run `npm test` in your terminal from the root folder of the project

package.json

@@ -23,7 +23,8 @@
     "clean": "rm -rf ./lib",
     "build": "npm run clean && npm run build:esm && npm run build:cjs",
     "build:esm": "tsc -p ./configs/tsconfig.esm.json",
-    "build:cjs": "tsc -p ./configs/tsconfig.cjs.json"
+    "build:cjs": "tsc -p ./configs/tsconfig.cjs.json",
+    "test": "mocha"
   },
   "repository": {
     "type": "git",
@@ -49,6 +50,13 @@
   },
   "homepage": "https://github.com/snyk-labs/modern-npm-package#readme",
   "devDependencies": {
+    "@types/mocha": "^9.1.1",
+    "mocha": "^10.0.0",
+    "ts-node": "^10.9.1",
     "typescript": "^4.7.4"
+  },
+  "dependencies": {
+    "@types/chai": "^4.3.3",
+    "chai": "^4.3.6"
   }
 }

tests/index.spec.ts

@@ -0,0 +1,27 @@
+import 'mocha';
+import { assert } from 'chai';
+
+import { helloWorld } from '../index';
+import npmPackage from '../index';
+
+describe('NPM Package', () => {
+  it('should be an object', () => {
+    assert.isObject(npmPackage);
+  });
+
+  it('should have a helloWorld property', () => {
+    assert.property(npmPackage, 'helloWorld');
+  });
+});
+
+describe('Hello World Function', () => {
+  it('should be a function', () => {
+    assert.isFunction(helloWorld);
+  });
+
+  it('should return the hello world message', () => {
+    const expected = 'Hello World from my example modern npm package!';
+    const actual = helloWorld();
+    assert.equal(actual, expected);
+  });
+});