Switch to ES Modules (#34)

* Switch to ESM
* update dependencies, pin to minor version

.editorconfig

@@ -10,6 +10,6 @@ insert_final_newline = true
 insert_final_newline = false
 trim_trailing_whitespace = false
 
-[*.{js,jsx,json,ts,tsx,yml}]
+[*.{js,json,ts,yml,yaml}]
 indent_size = 2
 indent_style = space

.eslintrc.json

@@ -7,7 +7,8 @@
   "parser": "@typescript-eslint/parser",
   "parserOptions": {
     "project": "tsconfig.json",
-    "sourceType": "module"
+    "sourceType": "module",
+    "ecmaVersion": 2020
   },
   "plugins": ["@typescript-eslint", "jest"],
   "extends": [

README.md

@@ -11,6 +11,7 @@
 🏃🏽 Instant Value: All basic tools included and configured:
 
 - [TypeScript][typescript] [4.5][typescript-4-5]
+- [ESM][esm]
 - [ESLint][eslint] with some initial rules recommendation
 - [Jest][jest] for fast unit testing and code coverage
 - Type definitions for Node.js and Jest
@@ -68,6 +69,10 @@ unzip node-typescript-boilerplate.zip && rm node-typescript-boilerplate.zip
 
 I recommend to [install][volta-getting-started] Volta and use it to manage your project's toolchain.
 
+### ES Modules
+
+Warning: This template is native [ESM][esm]. If your project uses CommonJS, you will have to [convert to ESM][sindresorhus-esm] or use the [dynamic import()][dynamic-import] function. Please do not open issues for questions regarding CommonJS or ESM.
+
 ### Writing tests in JavaScript
 
 Writing unit tests in TypeScript can sometimes be troublesome and confusing. Especially when mocking dependencies and using spies.
@@ -102,3 +107,6 @@ Licensed under the APLv2. See the [LICENSE](https://github.com/jsynowiec/node-ty
 [volta-tomdale]: https://twitter.com/tomdale/status/1162017336699838467?s=20
 [gh-actions]: https://github.com/features/actions
 [repo-template-action]: https://github.com/jsynowiec/node-typescript-boilerplate/generate
+[esm]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
+[sindresorhus-esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c
+[dynamic-import]: https://v8.dev/features/dynamic-import

jest.config.js

@@ -1,20 +1,22 @@
-module.exports = {
+export default {
+  preset: 'ts-jest/presets/js-with-ts',
   testEnvironment: 'node',
+  extensionsToTreatAsEsm: ['.ts'],
+  globals: {
+    'ts-jest': {
+      useESM: true,
+    },
+  },
+  moduleNameMapper: {
+    '^(\\.{1,2}/.*)\\.js$': '$1',
+  },
   transform: {
-    "^.+\\.tsx?$": "ts-jest"
+    "^.+\\.ts$": "ts-jest"
   },
-  moduleFileExtensions: [
-    "ts",
-    "tsx",
-    "js",
-    "jsx",
-    "json",
-    "node",
-  ],
-  testRegex: '(/__tests__/.*|(\\.|/)(test|spec))\\.(ts|js)x?$',
+  testRegex: '(/__tests__/.*|(\\.|/)(test|spec))\\.ts$',
   coverageDirectory: 'coverage',
   collectCoverageFrom: [
-    'src/**/*.{ts,tsx,js,jsx}',
+    'src/**/*.ts',
     '!src/**/*.d.ts',
   ],
 };