feat: ESNext by default, full ESM-CJS interop, max minification

README.md

@@ -140,13 +140,13 @@ export const sum = (a: number, b: number) => {
 if (process.env.NODE_ENV === 'production') {
   module.exports = require('./mylib.cjs.production.js');
 } else {
-  module.exports = require('./mylib.cjs.development.js');
+  module.exports = require('./mylib.development.cjs');
 }
 ```
 
 ```js
 // CommonJS Development Build
-// ./dist/mylib.cjs.development.js
+// ./dist/mylib.development.cjs
 'use strict';
 
 const sum = (a, b) => {
@@ -158,7 +158,7 @@ const sum = (a, b) => {
 };
 
 exports.sum = sum;
-//# sourceMappingURL=mylib.cjs.development.js.map
+//# sourceMappingURL=mylib.development.cjs.map
 ```
 
 ```js

package.json

@@ -38,7 +38,7 @@
     "templates"
   ],
   "engines": {
-    "node": ">=10"
+    "node": ">=14"
   },
   "dependencies": {
     "@babel/core": "^7.4.4",
@@ -48,62 +48,62 @@
     "@babel/preset-env": "^7.11.0",
     "@babel/traverse": "^7.11.5",
     "@rollup/plugin-babel": "^5.1.0",
-    "@rollup/plugin-commonjs": "^11.0.0",
+    "@rollup/plugin-commonjs": "^19.0.0",
     "@rollup/plugin-json": "^4.0.0",
-    "@rollup/plugin-node-resolve": "^9.0.0",
+    "@rollup/plugin-node-resolve": "^13.0.0",
     "@rollup/plugin-replace": "^2.2.1",
-    "@types/jest": "^25.2.1",
-    "@typescript-eslint/eslint-plugin": "^2.12.0",
-    "@typescript-eslint/parser": "^2.12.0",
+    "@types/jest": "^26.0.24",
+    "@typescript-eslint/eslint-plugin": "^4.28.2",
+    "@typescript-eslint/parser": "^4.28.2",
     "ansi-escapes": "^4.2.1",
     "asyncro": "^3.0.0",
     "babel-eslint": "^10.0.3",
     "babel-plugin-annotate-pure-calls": "^0.4.0",
     "babel-plugin-dev-expression": "^0.2.1",
-    "babel-plugin-macros": "^2.6.1",
-    "babel-plugin-polyfill-regenerator": "^0.0.4",
+    "babel-plugin-macros": "^3.1.0",
+    "babel-plugin-polyfill-regenerator": "^0.2.2",
     "babel-plugin-transform-rename-import": "^2.3.0",
     "camelcase": "^6.0.0",
     "chalk": "^4.0.0",
     "enquirer": "^2.3.4",
-    "eslint": "^6.1.0",
+    "eslint": "^7.30.0",
     "eslint-config-prettier": "^6.0.0",
-    "eslint-config-react-app": "^5.2.1",
-    "eslint-plugin-flowtype": "^3.13.0",
+    "eslint-config-react-app": "^6.0.0",
+    "eslint-plugin-flowtype": "^5.8.0",
     "eslint-plugin-import": "^2.18.2",
     "eslint-plugin-jsx-a11y": "^6.2.3",
     "eslint-plugin-prettier": "^3.1.0",
     "eslint-plugin-react": "^7.14.3",
-    "eslint-plugin-react-hooks": "^2.2.0",
-    "execa": "^4.0.3",
-    "fs-extra": "^9.0.0",
-    "jest": "^25.3.0",
-    "jest-watch-typeahead": "^0.5.0",
+    "eslint-plugin-react-hooks": "^4.2.0",
+    "execa": "^5.1.1",
+    "fs-extra": "^10.0.0",
+    "jest": "^27.0.6",
+    "jest-watch-typeahead": "^0.6.4",
     "jpjs": "^1.2.1",
     "lodash.merge": "^4.6.2",
-    "ora": "^4.0.3",
+    "ora": "^5.4.1",
     "pascal-case": "^3.1.1",
-    "prettier": "^1.19.1",
-    "progress-estimator": "^0.2.2",
+    "prettier": "^2.3.2",
+    "progress-estimator": "^0.3.0",
     "regenerator-runtime": "^0.13.7",
-    "rollup": "^1.32.1",
+    "rollup": "^2.52.8",
     "rollup-plugin-sourcemaps": "^0.6.2",
-    "rollup-plugin-terser": "^5.1.2",
-    "rollup-plugin-typescript2": "^0.27.3",
+    "rollup-plugin-terser": "^7.0.2",
+    "rollup-plugin-typescript2": "^0.30.0",
     "sade": "^1.4.2",
     "semver": "^7.1.1",
     "shelljs": "^0.8.3",
     "tiny-glob": "^0.2.6",
-    "ts-jest": "^25.3.1",
-    "tslib": "^1.9.3",
-    "typescript": "^3.7.3"
+    "ts-jest": "^27.0.3",
+    "tslib": "^2.3.0",
+    "typescript": "^4.3.5"
   },
   "devDependencies": {
-    "@types/eslint": "^6.1.2",
+    "@types/eslint": "^7.2.14",
     "@types/fs-extra": "^9.0.1",
     "@types/lodash": "^4.14.161",
-    "@types/node": "^14.11.1",
-    "@types/react": "^16.9.11",
+    "@types/node": "^16.0.1",
+    "@types/react": "^17.0.14",
     "@types/rollup-plugin-json": "^3.0.2",
     "@types/sade": "^1.6.0",
     "@types/semver": "^7.1.0",
@@ -112,18 +112,18 @@
     "autoprefixer": "^9.7.4",
     "babel-plugin-replace-identifiers": "^0.1.1",
     "cssnano": "^4.1.10",
-    "doctoc": "^1.4.0",
-    "husky": "^4.2.2",
-    "np": "^6.4.0",
-    "pretty-quick": "^2.0.0",
-    "react": "^16.8.6",
-    "react-dom": "^16.13.0",
-    "react-is": "^16.13.0",
+    "doctoc": "^2.0.1",
+    "husky": "^7.0.1",
+    "np": "^7.5.0",
+    "pretty-quick": "^3.1.1",
+    "react": "^17.0.2",
+    "react-dom": "^17.0.2",
+    "react-is": "^17.0.2",
     "rollup-plugin-postcss": "^2.5.0",
     "styled-components": "^5.0.1",
     "tiny-invariant": "^1.1.0",
     "tiny-warning": "^1.0.3",
-    "yarn-deduplicate": "^2.1.1"
+    "yarn-deduplicate": "^3.1.0"
   },
   "husky": {
     "hooks": {

src/createRollupConfig.ts

@@ -33,15 +33,20 @@ export async function createRollupConfig(
     ...opts,
   });
 
+  const isEsm = opts.format.includes('es') || opts.format.includes('esm');
+
   const shouldMinify =
-    opts.minify !== undefined ? opts.minify : opts.env === 'production';
+    opts.minify !== undefined ? opts.minify : opts.env === 'production' || isEsm;
+
+  let formatString = ['esm', 'cjs'].includes(opts.format) ? '' : opts.format;
+  let fileExtension = opts.format === 'esm' ? 'mjs' : 'cjs';
 
   const outputName = [
     `${paths.appDist}/${safePackageName(opts.name)}`,
-    opts.format,
+    formatString,
     opts.env,
     shouldMinify ? 'min' : '',
-    'js',
+    fileExtension,
   ]
     .filter(Boolean)
     .join('.');
@@ -102,14 +107,18 @@ export async function createRollupConfig(
       esModule: Boolean(tsCompilerOptions?.esModuleInterop),
       name: opts.name || safeVariableName(opts.name),
       sourcemap: true,
-      globals: { react: 'React', 'react-native': 'ReactNative' },
+      globals: { react: 'React', 'react-native': 'ReactNative', 'lodash-es': 'lodashEs', 'lodash/fp': 'lodashFp' },
       exports: 'named',
     },
     plugins: [
       !!opts.extractErrors && {
-        async transform(source: any) {
-          await findAndRecordErrorCodes(source);
-          return source;
+        async transform(code: string) {
+          try {
+            await findAndRecordErrorCodes(code);
+          } catch (e) {
+            return null;
+          }
+          return { code, map: null };
         },
       },
       resolve({
@@ -118,7 +127,7 @@ export async function createRollupConfig(
           'main',
           opts.target !== 'node' ? 'browser' : undefined,
         ].filter(Boolean) as string[],
-        extensions: [...RESOLVE_DEFAULTS.extensions, '.jsx'],
+        extensions: [...RESOLVE_DEFAULTS.extensions, '.cjs', '.mjs', '.jsx'],
       }),
       // all bundled external modules need to be converted from CJS to ESM
       commonjs({
@@ -189,30 +198,48 @@ export async function createRollupConfig(
         extensions: [...DEFAULT_BABEL_EXTENSIONS, 'ts', 'tsx'],
         passPerPreset: true,
         custom: {
-          targets: opts.target === 'node' ? { node: '10' } : undefined,
+          targets: opts.target === 'node' ? { node: '14' } : undefined,
           extractErrors: opts.extractErrors,
           format: opts.format,
         },
         babelHelpers: 'bundled',
       }),
       opts.env !== undefined &&
-        replace({
-          'process.env.NODE_ENV': JSON.stringify(opts.env),
-        }),
+      replace({
+        preventAssignment: true,
+        'process.env.NODE_ENV': JSON.stringify(opts.env),
+      }),
       sourceMaps(),
       shouldMinify &&
-        terser({
-          sourcemap: true,
-          output: { comments: false },
-          compress: {
-            keep_infinity: true,
-            pure_getters: true,
-            passes: 10,
-          },
-          ecma: 5,
-          toplevel: opts.format === 'cjs',
-          warnings: true,
-        }),
+      terser({
+        output: { comments: false },
+        compress: {
+          keep_infinity: true,
+          pure_getters: true,
+          passes: 10,
+        },
+        ecma: opts.legacy ? 5 : 2020,
+        module: isEsm,
+        toplevel: opts.format === 'cjs' || isEsm,
+        warnings: true,
+      }),
+      /**
+       * Ensure there's an empty default export to prevent runtime errors.
+       *
+       * @see https://www.npmjs.com/package/rollup-plugin-export-default
+       */
+       {
+        renderChunk: async (code: string, chunk: any) => {
+          if (chunk.exports.includes('default') || !isEsm) {
+            return null;
+          }
+
+          return {
+            code: `${code}\nexport default {};`,
+            map: null,
+          };
+        },
+      },
     ],
   };
 }

src/errors/extractErrors.ts

@@ -30,23 +30,26 @@ const babelParserOptions: ParserOptions = {
 } as ParserOptions; // workaround for trailingFunctionCommas syntax
 
 export async function extractErrors(opts: any) {
-  if (!opts || !('errorMapFilePath' in opts)) {
+  if (!opts || !opts.errorMapFilePath) {
     throw new Error(
       'Missing options. Ensure you pass an object with `errorMapFilePath`.'
     );
   }
 
-  if (!opts.name || !('name' in opts)) {
+  if (!opts.name || !opts.name) {
     throw new Error('Missing options. Ensure you pass --name flag to tsdx');
   }
 
   const errorMapFilePath = opts.errorMapFilePath;
   let existingErrorMap: any;
   try {
-    // Using `fs.readFile` instead of `require` here, because `require()`
-    // calls are cached, and the cache map is not properly invalidated after
-    // file changes.
-    existingErrorMap = JSON.parse(await fs.readFile(errorMapFilePath, 'utf8'));
+    /**
+     * Using `fs.readFile` instead of `require` here, because `require()` calls
+     * are cached, and the cache map is not properly invalidated after file
+     * changes.
+     */
+    const fileContents = await fs.readFile(errorMapFilePath, 'utf-8');
+    existingErrorMap = JSON.parse(fileContents);
   } catch (e) {
     existingErrorMap = {};
   }