[core] Improve tree-shakeability

.size-limit.js

@@ -18,11 +18,17 @@ module.exports = [
     path: 'packages/material-ui/build/Paper/index.js',
     limit: '18.8 KB',
   },
+  {
+    name: 'The initial cost paid for using one component with ES modules',
+    webpack: true,
+    path: 'packages/material-ui/build/esm/Paper/index.js',
+    limit: '17.9 KB',
+  },
   {
     name: 'The size of the @material-ui/core modules',
     webpack: true,
     path: 'packages/material-ui/build/index.js',
-    limit: '94.6 KB',
+    limit: '91.2 KB',
   },
   {
     name: 'The size of the @material-ui/styles modules',
@@ -43,24 +49,25 @@ module.exports = [
     limit: '900 B',
   },
   {
+    // why we use esm here: https://github.com/mui-org/material-ui/pull/13391#issuecomment-459692816
     name: 'The size of the @material-ui/core/Button component',
     webpack: true,
-    path: 'packages/material-ui/build/Button/index.js',
-    limit: '26.7 KB',
+    path: 'packages/material-ui/build/esm/Button/index.js',
+    limit: '24.6 KB',
   },
   {
     // vs https://bundlephobia.com/result?p=react-modal
     name: 'The size of the @material-ui/core/Modal component',
     webpack: true,
-    path: 'packages/material-ui/build/Modal/index.js',
-    limit: '26.4 KB',
+    path: 'packages/material-ui/build/esm/Modal/index.js',
+    limit: '24.1 KB',
   },
   {
     // vs https://bundlephobia.com/result?p=react-popper
     name: 'The size of the @material-ui/core/Popper component',
     webpack: true,
-    path: 'packages/material-ui/build/Popper/index.js',
-    limit: '10.8 KB',
+    path: 'packages/material-ui/build/esm/Popper/index.js',
+    limit: '9.7 KB',
   },
   {
     // vs https://bundlephobia.com/result?p=react-responsive
@@ -80,6 +87,6 @@ module.exports = [
     name: 'The docs home page',
     webpack: false,
     path: `.next/static/${buildId}/pages/index.js`,
-    limit: '7 KB',
+    limit: '6.2 KB',
   },
 ];

babel.config.js

@@ -21,7 +21,7 @@ if (process.env.BABEL_ENV === 'es') {
     [
       '@babel/preset-env',
       {
-        modules: ['modules', 'production-umd'].includes(process.env.BABEL_ENV) ? false : 'commonjs',
+        modules: ['esm', 'production-umd'].includes(process.env.BABEL_ENV) ? false : 'commonjs',
       },
     ],
   ];
@@ -36,6 +36,18 @@ const defaultAlias = {
   '@material-ui/system': './packages/material-ui-system/src',
 };
 
+const productionPlugins = [
+  'transform-react-constant-elements',
+  'transform-dev-warning',
+  ['react-remove-properties', { properties: ['data-mui-test'] }],
+  [
+    'transform-react-remove-prop-types',
+    {
+      mode: 'unsafe-wrap',
+    },
+  ],
+];
+
 module.exports = {
   presets: defaultPresets.concat(['@babel/preset-react']),
   plugins: [
@@ -46,17 +58,8 @@ module.exports = {
   ],
   ignore: [/@babel[\\|/]runtime/],
   env: {
-    test: {
-      sourceMaps: 'both',
-      plugins: [
-        [
-          'babel-plugin-module-resolver',
-          {
-            root: ['./'],
-            alias: defaultAlias,
-          },
-        ],
-      ],
+    cjs: {
+      plugins: productionPlugins,
     },
     coverage: {
       plugins: [
@@ -124,47 +127,26 @@ module.exports = {
         ['transform-react-remove-prop-types', { mode: 'remove' }],
       ],
     },
+    esm: {
+      plugins: productionPlugins,
+    },
     es: {
-      plugins: [
-        'transform-react-constant-elements',
-        'transform-dev-warning',
-        ['react-remove-properties', { properties: ['data-mui-test'] }],
-        [
-          'transform-react-remove-prop-types',
-          {
-            mode: 'unsafe-wrap',
-          },
-        ],
-      ],
-      // It's most likely a babel bug.
-      // We are using this ignore option in the CLI command but that has no effect.
-      ignore: ['**/*.test.js'],
+      plugins: productionPlugins,
     },
     production: {
-      plugins: [
-        'transform-react-constant-elements',
-        'transform-dev-warning',
-        ['react-remove-properties', { properties: ['data-mui-test'] }],
-        [
-          'transform-react-remove-prop-types',
-          {
-            mode: 'unsafe-wrap',
-          },
-        ],
-      ],
-      // It's most likely a babel bug.
-      // We are using this ignore option in the CLI command but that has no effect.
-      ignore: ['**/*.test.js'],
+      plugins: productionPlugins,
     },
     'production-umd': {
+      plugins: productionPlugins,
+    },
+    test: {
+      sourceMaps: 'both',
       plugins: [
-        'transform-react-constant-elements',
-        'transform-dev-warning',
-        ['react-remove-properties', { properties: ['data-mui-test'] }],
         [
-          'transform-react-remove-prop-types',
+          'babel-plugin-module-resolver',
           {
-            mode: 'unsafe-wrap',
+            root: ['./'],
+            alias: defaultAlias,
           },
         ],
       ],

packages/material-ui-docs/package.json

@@ -22,13 +22,13 @@
   },
   "homepage": "https://github.com/mui-org/material-ui/tree/master/packages/material-ui-lab",
   "scripts": {
-    "test": "exit 0",
-    "prebuild": "rimraf build",
-    "build:es2015": "cross-env NODE_ENV=production babel --config-file ../../babel.config.js ./src --out-dir ./build",
-    "build:es2015modules": "cross-env NODE_ENV=production BABEL_ENV=modules babel --config-file ../../babel.config.js ./src/index.js --out-file ./build/index.es.js",
+    "build": "yarn build:cjs && yarn build:esm && yarn build:copy-files",
+    "build:cjs": "cross-env NODE_ENV=production BABEL_ENV=cjs babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore \"**/*.test.js\"",
+    "build:esm": "cross-env NODE_ENV=production BABEL_ENV=esm babel --config-file ../../babel.config.js ./src --out-dir ./build/esm --ignore \"**/*.test.js\"",
     "build:copy-files": "babel-node --config-file ../../babel.config.js ./scripts/copy-files.js",
-    "build": "yarn build:es2015 && yarn build:es2015modules && yarn build:copy-files",
-    "release": "yarn build && npm publish build"
+    "prebuild": "rimraf build",
+    "release": "yarn build && npm publish build",
+    "test": "exit 0"
   },
   "peerDependencies": {
     "@material-ui/core": "^3.0.0",

packages/material-ui-docs/scripts/copy-files.js

@@ -38,7 +38,7 @@ async function addLicense(packageData) {
  */
 `;
   await Promise.all(
-    ['../build/index.js', '../build/index.es.js'].map(file =>
+    ['../build/index.js', '../build/esm/index.js'].map(file =>
       prepend(path.resolve(__dirname, file), license),
     ),
   );

packages/material-ui-icons/package.json

@@ -22,10 +22,11 @@
   },
   "homepage": "https://github.com/mui-org/material-ui/tree/master/packages/material-ui-icons",
   "scripts": {
-    "build": "yarn build:es2015 && yarn build:es2015modules && yarn build:typings && yarn build:copy-files",
+    "build": "yarn build:cjs && yarn build:esm && yarn build:es && yarn build:typings && yarn build:copy-files",
+    "build:cjs": "cross-env NODE_ENV=production BABEL_ENV=cjs babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore \"**/*.test.js\"",
+    "build:esm": "cross-env NODE_ENV=production BABEL_ENV=esm babel --config-file ../../babel.config.js ./src --out-dir ./build/esm --ignore \"**/*.test.js\"",
+    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore \"**/*.test.js\"",
     "build:copy-files": "babel-node --config-file ../../babel.config.js ./scripts/copy-files.js",
-    "build:es2015": "cross-env NODE_ENV=production babel --config-file ../../babel.config.js ./src --out-dir ./build",
-    "build:es2015modules": "cross-env NODE_ENV=production BABEL_ENV=modules babel --config-file ../../babel.config.js ./src/index.js --out-file ./build/index.es.js",
     "build:typings": "babel-node --config-file ../../babel.config.js ./scripts/create-typings.js",
     "prebuild": "rimraf material-design-icons && rimraf build",
     "release": "yarn build && npm publish build",

packages/material-ui-lab/package.json

@@ -22,11 +22,11 @@
   },
   "homepage": "https://github.com/mui-org/material-ui/tree/master/packages/material-ui-lab",
   "scripts": {
-    "build": "yarn build:es2015 && yarn build:es2015modules && yarn build:es && yarn build:copy-files",
+    "build": "yarn build:cjs && yarn build:esm && yarn build:es && yarn build:copy-files",
+    "build:cjs": "cross-env NODE_ENV=production BABEL_ENV=cjs babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore \"**/*.test.js\"",
+    "build:esm": "cross-env NODE_ENV=production BABEL_ENV=esm babel --config-file ../../babel.config.js ./src --out-dir ./build/esm --ignore \"**/*.test.js\"",
+    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore \"**/*.test.js\"",
     "build:copy-files": "babel-node --config-file ../../babel.config.js ./scripts/copy-files.js",
-    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore *.test.js",
-    "build:es2015": "cross-env NODE_ENV=production babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore *.test.js",
-    "build:es2015modules": "cross-env NODE_ENV=production BABEL_ENV=modules babel --config-file ../../babel.config.js ./src/index.js --out-file ./build/index.es.js",
     "prebuild": "rimraf build",
     "release": "yarn build && npm publish build",
     "test": "cd ../../ && cross-env NODE_ENV=test mocha 'packages/material-ui-lab/**/*.test.js' --exclude '**/node_modules/**'",

packages/material-ui-lab/scripts/copy-files.js

@@ -10,6 +10,39 @@ async function copyFile(file) {
   console.log(`Copied ${file} to ${buildPath}`);
 }
 
+/**
+ * Puts a package.json into every immediate child directory of rootDir.
+ * That package.json contains information about esm for bundlers so that imports
+ * like import Typography from '@material-ui/core/Typography' are tree-shakeable.
+ *
+ * It also tests that an this import can be used in typescript by checking
+ * if an index.d.ts is present at that path.
+ *
+ * @param {string} rootDir
+ */
+function createModulePackages(srcDir, outDir) {
+  const directoryPackages = glob.sync('*/index.js', { cwd: srcDir }).map(path.dirname);
+  return Promise.all(
+    directoryPackages.map(directoryPackage => {
+      const packageJson = {
+        sideEffects: false,
+        module: path.join('..', 'esm', directoryPackage, 'index.js'),
+      };
+      const packageJsonPath = path.join(outDir, directoryPackage, 'package.json');
+
+      return Promise.all([
+        fse.exists(path.join(outDir, directoryPackage, 'index.d.ts')),
+        fse.writeFile(packageJsonPath, JSON.stringify(packageJson, null, 2)),
+      ]).then(([typingsExist]) => {
+        if (!typingsExist) {
+          return Promise.reject(new Error(`index.d.ts for ${directoryPackage} is missing`));
+        }
+        return Promise.resolve(packageJsonPath);
+      });
+    }),
+  );
+}
+
 function typescriptCopy(from, to) {
   const files = glob.sync('**/*.d.ts', { cwd: from });
   const cmds = files.map(file => fse.copy(path.resolve(from, file), path.resolve(to, file)));
@@ -22,7 +55,7 @@ async function createPackageFile() {
   const newPackageData = {
     ...packageDataOther,
     main: './index.js',
-    module: './index.es.js',
+    module: './esm/index.js',
     private: false,
     typings: './index.d.ts',
   };
@@ -47,7 +80,7 @@ async function addLicense(packageData) {
  */
 `;
   await Promise.all(
-    ['../build/index.js', '../build/index.es.js'].map(file =>
+    ['../build/index.js', '../build/esm/index.js'].map(file =>
       prepend(path.resolve(__dirname, file), license),
     ),
   );
@@ -64,6 +97,11 @@ async function run() {
     typescriptCopy(from, path.resolve(__dirname, '../build')),
     typescriptCopy(from, path.resolve(__dirname, '../build/es')),
   ]);
+
+  await createModulePackages(
+    path.resolve(__dirname, '../src'),
+    path.resolve(__dirname, '../build'),
+  );
 }
 
 run();

packages/material-ui-styles/package.json

@@ -22,11 +22,11 @@
   },
   "homepage": "https://github.com/mui-org/material-ui/tree/master/packages/material-ui-styles",
   "scripts": {
-    "build": "yarn build:es2015 && yarn build:es2015modules && yarn build:es && yarn build:copy-files",
+    "build": "yarn build:cjs && yarn build:esm && yarn build:es && yarn build:copy-files",
+    "build:cjs": "cross-env NODE_ENV=production BABEL_ENV=cjs babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore \"**/*.test.js\"",
+    "build:esm": "cross-env NODE_ENV=production BABEL_ENV=esm babel --config-file ../../babel.config.js ./src --out-dir ./build/esm --ignore \"**/*.test.js\"",
+    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore \"**/*.test.js\"",
     "build:copy-files": "babel-node --config-file ../../babel.config.js ./scripts/copy-files.js",
-    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore *.test.js",
-    "build:es2015": "cross-env NODE_ENV=production babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore *.test.js",
-    "build:es2015modules": "cross-env NODE_ENV=production BABEL_ENV=modules babel --config-file ../../babel.config.js ./src/index.js --out-file ./build/index.es.js",
     "prebuild": "rimraf build",
     "release": "yarn build && npm publish build",
     "test": "cd ../../ && cross-env NODE_ENV=test mocha 'packages/material-ui-styles/**/*.test.js' --exclude '**/node_modules/**'",

packages/material-ui-styles/scripts/copy-files.js

@@ -22,7 +22,7 @@ async function createPackageFile() {
   const newPackageData = {
     ...packageDataOther,
     main: './index.js',
-    module: './index.es.js',
+    module: './esm/index.js',
     private: false,
     typings: './index.d.ts',
   };
@@ -47,7 +47,7 @@ async function addLicense(packageData) {
  */
 `;
   await Promise.all(
-    ['../build/index.js', '../build/index.es.js'].map(file =>
+    ['../build/index.js', '../build/esm/index.js'].map(file =>
       prepend(path.resolve(__dirname, file), license),
     ),
   );

packages/material-ui-system/package.json

@@ -22,11 +22,11 @@
   },
   "homepage": "https://github.com/mui-org/material-ui/tree/master/packages/material-ui-system",
   "scripts": {
-    "build": "yarn build:es2015 && yarn build:es2015modules && yarn build:es && yarn build:copy-files",
+    "build": "yarn build:cjs && yarn build:esm && yarn build:es && yarn build:copy-files",
+    "build:cjs": "cross-env NODE_ENV=production BABEL_ENV=cjs babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore \"**/*.test.js\"",
+    "build:esm": "cross-env NODE_ENV=production BABEL_ENV=esm babel --config-file ../../babel.config.js ./src --out-dir ./build/esm --ignore \"**/*.test.js\"",
+    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore \"**/*.test.js\"",
     "build:copy-files": "babel-node --config-file ../../babel.config.js ./scripts/copy-files.js",
-    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore *.test.js",
-    "build:es2015": "cross-env NODE_ENV=production babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore *.test.js",
-    "build:es2015modules": "cross-env NODE_ENV=production BABEL_ENV=modules babel --config-file ../../babel.config.js ./src/index.js --out-file ./build/index.es.js",
     "prebuild": "rimraf build",
     "release": "yarn build && npm publish build",
     "test": "cd ../../ && cross-env NODE_ENV=test mocha 'packages/material-ui-system/**/*.test.js' --exclude '**/node_modules/**'"

packages/material-ui-system/scripts/copy-files.js

@@ -22,7 +22,7 @@ async function createPackageFile() {
   const newPackageData = {
     ...packageDataOther,
     main: './index.js',
-    module: './index.es.js',
+    module: './esm/index.js',
     private: false,
   };
   const buildPath = path.resolve(__dirname, '../build/package.json');
@@ -46,7 +46,7 @@ async function addLicense(packageData) {
  */
 `;
   await Promise.all(
-    ['../build/index.js', '../build/index.es.js'].map(file =>
+    ['../build/index.js', '../build/esm/index.js'].map(file =>
       prepend(path.resolve(__dirname, file), license),
     ),
   );

packages/material-ui-utils/package.json

@@ -22,11 +22,11 @@
   },
   "homepage": "https://github.com/mui-org/material-ui/tree/master/packages/material-ui-utils",
   "scripts": {
-    "build": "yarn build:es2015 && yarn build:es2015modules && yarn build:es && yarn build:copy-files",
+    "build": "yarn build:cjs && yarn build:esm && yarn build:es && yarn build:copy-files",
+    "build:cjs": "cross-env NODE_ENV=production BABEL_ENV=cjs babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore \"**/*.test.js\"",
+    "build:esm": "cross-env NODE_ENV=production BABEL_ENV=esm babel --config-file ../../babel.config.js ./src --out-dir ./build/esm --ignore \"**/*.test.js\"",
+    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore \"**/*.test.js\"",
     "build:copy-files": "babel-node --config-file ../../babel.config.js ./scripts/copy-files.js",
-    "build:es": "cross-env NODE_ENV=production BABEL_ENV=es babel --config-file ../../babel.config.js ./src --out-dir ./build/es --ignore *.test.js",
-    "build:es2015": "cross-env NODE_ENV=production babel --config-file ../../babel.config.js ./src --out-dir ./build --ignore *.test.js",
-    "build:es2015modules": "cross-env NODE_ENV=production BABEL_ENV=modules babel --config-file ../../babel.config.js ./src/index.js --out-file ./build/index.es.js",
     "prebuild": "rimraf build",
     "release": "yarn build && npm publish build",
     "test": "cd ../../ && cross-env NODE_ENV=test mocha 'packages/material-ui-utils/**/*.test.js' --exclude '**/node_modules/**'"

packages/material-ui-utils/scripts/copy-files.js

@@ -22,7 +22,7 @@ async function createPackageFile() {
   const newPackageData = {
     ...packageDataOther,
     main: './index.js',
-    module: './index.es.js',
+    module: './esm/index.js',
     private: false,
   };
   const buildPath = path.resolve(__dirname, '../build/package.json');
@@ -46,7 +46,7 @@ async function addLicense(packageData) {
  */
 `;
   await Promise.all(
-    ['../build/index.js', '../build/index.es.js'].map(file =>
+    ['../build/index.js', '../esm/index.js'].map(file =>
       prepend(path.resolve(__dirname, file), license),
     ),
   );