Split @babel/runtime into 2 modules via @babel/runtime-corejs2 (#8266)

In Babel 6, we had `@babel/runtime` which _always_ uses `core-js` in its helpers, meaning that anyone who wants to use our helpers in a centralized modular way had to also use core-js, which isn't always ideal.

Early in the Babel 7 alpha, we added a `useBuiltins: true` option that would use separate copies of the helpers that would skip loading `core-js`, but this _still_ requires users to have an indirect npm dependency on `core-js`.

This PR splits our setup into two separate runtimes:

* ```
  'plugins': [
    ['transform-runtime'],
  ]
  ```
  with `npm install --save @babel/runtime` that just includes our helpers, and relies on users to globally polyfill any APIs they need.
* ```
  'plugins': [
    ['transform-runtime', { corejs: 2 }],
  ]
  ```
  with `npm install --save @babel/runtime-corejs2` that includes everything `@babel/runtime` does, but also includes a passthrough API for `corejs@2.x` and rewrites all of the helper modules to reference `core-js`.

.eslintignore

@@ -4,8 +4,9 @@
 package.json
 lerna.json
 packages/babel-runtime
-!packages/babel-runtime/scripts
-!packages/babel-runtime/core-js.js
+!packages/babel-plugin-transform-runtime/scripts
+!packages/babel-runtime-corejs2/core-js.js
+packages/babel-runtime-corejs2
 packages/*/node_modules
 packages/*/lib
 packages/*/dist

.gitignore

@@ -12,24 +12,27 @@ coverage
 dist
 /.package.json
 package-lock.json
-/packages/babel-runtime/core-js/**/*.js
-!/packages/babel-runtime/core-js/map.js
+
 /packages/babel-runtime/helpers/*.js
 !/packages/babel-runtime/helpers/toArray.js
 !/packages/babel-runtime/helpers/iterableToArray.js
 !/packages/babel-runtime/helpers/temporalRef.js
-/packages/babel-runtime/helpers/builtin/*.js
-!/packages/babel-runtime/helpers/builtin/toArray.js
-!/packages/babel-runtime/helpers/builtin/iterableToArray.js
-!/packages/babel-runtime/helpers/builtin/temporalRef.js
-/packages/babel-runtime/helpers/builtin/es6/*.js
-!/packages/babel-runtime/helpers/builtin/es6/toArray.js
-!/packages/babel-runtime/helpers/builtin/es6/iterableToArray.js
-!/packages/babel-runtime/helpers/builtin/es6/temporalRef.js
-/packages/babel-runtime/helpers/es6/*.js
-!/packages/babel-runtime/helpers/es6/toArray.js
-!/packages/babel-runtime/helpers/es6/iterableToArray.js
-!/packages/babel-runtime/helpers/es6/temporalRef.js
+/packages/babel-runtime/helpers/esm/*.js
+!/packages/babel-runtime/helpers/esm/toArray.js
+!/packages/babel-runtime/helpers/esm/iterableToArray.js
+!/packages/babel-runtime/helpers/esm/temporalRef.js
+
+/packages/babel-runtime-corejs2/helpers/*.js
+!/packages/babel-runtime-corejs2/helpers/toArray.js
+!/packages/babel-runtime-corejs2/helpers/iterableToArray.js
+!/packages/babel-runtime-corejs2/helpers/temporalRef.js
+/packages/babel-runtime-corejs2/helpers/esm/*.js
+!/packages/babel-runtime-corejs2/helpers/esm/toArray.js
+!/packages/babel-runtime-corejs2/helpers/esm/iterableToArray.js
+!/packages/babel-runtime-corejs2/helpers/esm/temporalRef.js
+/packages/babel-runtime-corejs2/core-js/**/*.js
+!/packages/babel-runtime-corejs2/core-js/map.js
+
 /packages/babel-register/test/.babel
 /packages/babel-cli/test/tmp
 /packages/babel-node/test/tmp

Makefile

@@ -31,7 +31,7 @@ build-preset-env-standalone:
 build-dist: build
 	cd packages/babel-polyfill; \
 	scripts/build-dist.sh
-	cd packages/babel-runtime; \
+	cd packages/babel-plugin-transform-runtime; \
 	node scripts/build-dist.js
 
 watch: clean clean-lib
@@ -108,7 +108,8 @@ publish:
 	git pull --rebase
 	make clean-lib
 	rm -rf packages/babel-runtime/helpers
-	rm -rf packages/babel-runtime/core-js
+	rm -rf packages/babel-runtime-corejs2/helpers
+	rm -rf packages/babel-runtime-corejs2/core-js
 	BABEL_ENV=production make build-dist
 	make test
 	# not using lerna independent mode atm, so only update packages that have changed since we use ^
@@ -120,7 +121,7 @@ bootstrap: clean-all
 	yarn --ignore-engines
 	./node_modules/.bin/lerna bootstrap -- --ignore-engines
 	make build
-	cd packages/babel-runtime; \
+	cd packages/babel-plugin-transform-runtime; \
 	node scripts/build-dist.js
 
 clean-lib:

packages/babel-plugin-transform-regenerator/test/fixtures/regression/T7041/output.js

@@ -1,12 +1,10 @@
 var _regeneratorRuntime = require("@babel/runtime/regenerator");
 
-var _Object$keys = require("@babel/runtime/core-js/object/keys");
-
 var _marked =
 /*#__PURE__*/
 _regeneratorRuntime.mark(fn);
 
-_Object$keys({});
+Object.keys({});
 
 function fn() {
   return _regeneratorRuntime.wrap(function fn$(_context) {

packages/babel-plugin-transform-runtime/.npmignore

@@ -1,3 +1,4 @@
+scripts
 src
 test
 *.log

packages/babel-plugin-transform-runtime/package.json

@@ -17,6 +17,11 @@
   },
   "devDependencies": {
     "@babel/core": "7.0.0-beta.55",
-    "@babel/helper-plugin-test-runner": "7.0.0-beta.55"
+    "@babel/helpers": "7.0.0-beta.55",
+    "@babel/helper-plugin-test-runner": "7.0.0-beta.55",
+    "@babel/plugin-transform-runtime": "7.0.0-beta.55",
+    "@babel/template": "7.0.0-beta.55",
+    "@babel/preset-env": "7.0.0-beta.55",
+    "@babel/types": "7.0.0-beta.53"
   }
 }

packages/babel-plugin-transform-runtime/scripts/build-dist.js

@@ -0,0 +1,158 @@
+"use strict";
+
+const path = require("path");
+const outputFile = require("output-file-sync");
+const helpers = require("@babel/helpers");
+const babel = require("@babel/core");
+const template = require("@babel/template");
+const t = require("@babel/types");
+
+const transformRuntime = require("../");
+const corejs2Definitions = require("../lib/definitions").default;
+
+writeHelpers("@babel/runtime");
+
+writeCoreJS2("@babel/runtime-corejs2");
+writeHelpers("@babel/runtime-corejs2", { corejs: 2 });
+
+function writeCoreJS2(runtimeName) {
+  const pkgDirname = getRuntimeRoot(runtimeName);
+
+  const paths = ["is-iterable", "get-iterator"];
+
+  Object.keys(corejs2Definitions.builtins).forEach(key => {
+    const path = corejs2Definitions.builtins[key];
+    paths.push(path);
+  });
+
+  Object.keys(corejs2Definitions.methods).forEach(key => {
+    const props = corejs2Definitions.methods[key];
+    Object.keys(props).forEach(key2 => {
+      paths.push(props[key2]);
+    });
+  });
+
+  paths.forEach(function(corePath) {
+    outputFile(
+      path.join(pkgDirname, "core-js", `${corePath}.js`),
+      `module.exports = require("core-js/library/fn/${corePath}");`
+    );
+  });
+}
+
+function writeHelpers(runtimeName, { corejs } = {}) {
+  writeHelperFiles(runtimeName, { corejs, esm: false });
+  writeHelperFiles(runtimeName, { corejs, esm: true });
+}
+
+function writeHelperFiles(runtimeName, { esm, corejs }) {
+  const pkgDirname = getRuntimeRoot(runtimeName);
+
+  for (const helperName of helpers.list) {
+    const helperFilename = path.join(
+      pkgDirname,
+      "helpers",
+      esm ? "esm" : "",
+      `${helperName}.js`
+    );
+
+    outputFile(
+      helperFilename,
+      buildHelper(runtimeName, pkgDirname, helperFilename, helperName, {
+        esm,
+        corejs,
+      })
+    );
+  }
+}
+
+function getRuntimeRoot(runtimeName) {
+  return path.resolve(
+    __dirname,
+    "..",
+    "..",
+    runtimeName.replace(/^@babel\//, "babel-")
+  );
+}
+
+function buildHelper(
+  runtimeName,
+  pkgDirname,
+  helperFilename,
+  helperName,
+  { esm, corejs }
+) {
+  const tree = t.program([], [], esm ? "module" : "script");
+  const dependencies = {};
+  let bindings = null;
+
+  if (!esm) {
+    bindings = [];
+    for (const dep of helpers.getDependencies(helperName)) {
+      const id = (dependencies[dep] = t.identifier(t.toIdentifier(dep)));
+      tree.body.push(template.statement.ast`
+        var ${id} = require("${`./${dep}`}");
+      `);
+      bindings.push(id.name);
+    }
+  }
+
+  const helper = helpers.get(
+    helperName,
+    dep => dependencies[dep],
+    esm ? null : template.expression.ast`module.exports`,
+    bindings
+  );
+  tree.body.push(...helper.nodes);
+
+  return babel.transformFromAst(tree, null, {
+    presets: [[require("@babel/preset-env"), { modules: false }]],
+    plugins: [
+      [transformRuntime, { corejs, useESModules: esm }],
+      buildRuntimeRewritePlugin(
+        runtimeName,
+        path.relative(path.dirname(helperFilename), pkgDirname),
+        helperName
+      ),
+    ],
+  }).code;
+}
+
+function buildRuntimeRewritePlugin(runtimeName, relativePath, helperName) {
+  function adjustImportPath(node, relativePath) {
+    node.value =
+      helpers.list.indexOf(node.value) !== -1
+        ? `./${node.value}`
+        : node.value.replace(runtimeName + "/", relativePath + "/");
+  }
+
+  return {
+    pre(file) {
+      const original = file.get("helperGenerator");
+      file.set("helperGenerator", name => {
+        // make sure that helpers won't insert circular references to themselves
+        if (name === helperName) return false;
+
+        return original(name);
+      });
+    },
+    visitor: {
+      ImportDeclaration(path) {
+        adjustImportPath(path.get("source").node, relativePath);
+      },
+      CallExpression(path) {
+        if (
+          !path.get("callee").isIdentifier({ name: "require" }) ||
+          path.get("arguments").length !== 1 ||
+          !path.get("arguments")[0].isStringLiteral()
+        ) {
+          return;
+        }
+
+        // replace any reference to @babel/runtime and other helpers
+        // with a relative path
+        adjustImportPath(path.get("arguments")[0].node, relativePath);
+      },
+    },
+  };
+}

packages/babel-plugin-transform-runtime/src/index.js

@@ -8,29 +8,84 @@ export default declare((api, options) => {
   api.assertVersion(7);
 
   const {
-    helpers,
-    moduleName = "@babel/runtime",
-    polyfill,
-    regenerator,
-    useBuiltIns,
-    useESModules,
+    corejs: corejsVersion = false,
+    helpers: useRuntimeHelpers = true,
+    regenerator: useRuntimeRegenerator = true,
+    useESModules = false,
     version: runtimeVersion = "7.0.0-beta.0",
   } = options;
-  const regeneratorEnabled = regenerator !== false;
-  const notPolyfillOrDoesUseBuiltIns = polyfill === false || useBuiltIns;
-  const isPolyfillAndUseBuiltIns = polyfill && useBuiltIns;
-  const baseHelpersDir = useBuiltIns ? "helpers/builtin" : "helpers";
-  const helpersDir = useESModules ? `${baseHelpersDir}/es6` : baseHelpersDir;
+
+  if (typeof useRuntimeRegenerator !== "boolean") {
+    throw new Error(
+      "The 'regenerator' option must be undefined, or a boolean.",
+    );
+  }
+  if (typeof useRuntimeHelpers !== "boolean") {
+    throw new Error("The 'helpers' option must be undefined, or a boolean.");
+  }
+  if (typeof useESModules !== "boolean") {
+    throw new Error(
+      "The 'useESModules' option must be undefined, or a boolean.",
+    );
+  }
+  if (
+    corejsVersion !== false &&
+    (typeof corejsVersion !== "number" || corejsVersion !== 2) &&
+    (typeof corejsVersion !== "string" || corejsVersion !== "2")
+  ) {
+    throw new Error(
+      `The 'corejs' option must be undefined, false, or 2, or '2', ` +
+        `but got ${JSON.stringify(corejsVersion)}.`,
+    );
+  }
 
   function has(obj, key) {
     return Object.prototype.hasOwnProperty.call(obj, key);
   }
+  if (has(options, "useBuiltIns")) {
+    if (options.useBuiltIns) {
+      throw new Error(
+        "The 'useBuiltIns' option has been removed. The @babel/runtime " +
+          "module now uses builtins by default.",
+      );
+    } else {
+      throw new Error(
+        "The 'useBuiltIns' option has been removed. Use the 'corejs'" +
+          "option with value '2' to polyfill with CoreJS 2.x via @babel/runtime.",
+      );
+    }
+  }
+  if (has(options, "polyfill")) {
+    if (options.polyfill === false) {
+      throw new Error(
+        "The 'polyfill' option has been removed. The @babel/runtime " +
+          "module now skips polyfilling by default.",
+      );
+    } else {
+      throw new Error(
+        "The 'polyfill' option has been removed. Use the 'corejs'" +
+          "option with value '2' to polyfill with CoreJS 2.x via @babel/runtime.",
+      );
+    }
+  }
+  if (has(options, "moduleName")) {
+    throw new Error(
+      "The 'moduleName' option has been removed. @babel/transform-runtime " +
+        "no longer supports arbitrary runtimes.",
+    );
+  }
+
+  const helpersDir = useESModules ? "helpers/esm" : "helpers";
+  const injectCoreJS2 = `${corejsVersion}` === "2";
+  const moduleName = injectCoreJS2
+    ? "@babel/runtime-corejs2"
+    : "@babel/runtime";
 
   const HEADER_HELPERS = ["interopRequireWildcard", "interopRequireDefault"];
 
   return {
     pre(file) {
-      if (helpers !== false) {
+      if (useRuntimeHelpers) {
         file.set("helperGenerator", name => {
           // If the helper didn't exist yet at the version given, we bail
           // out and let Babel either insert it directly, or throw an error
@@ -58,14 +113,6 @@ export default declare((api, options) => {
         });
       }
 
-      if (isPolyfillAndUseBuiltIns) {
-        throw new Error(
-          "The polyfill option conflicts with useBuiltIns; use one or the other",
-        );
-      }
-
-      this.moduleName = moduleName;
-
       const cache = new Map();
 
       this.addDefaultImport = (source, nameHint, blockHoist) => {
@@ -94,17 +141,17 @@ export default declare((api, options) => {
     visitor: {
       ReferencedIdentifier(path) {
         const { node, parent, scope } = path;
-        if (node.name === "regeneratorRuntime" && regeneratorEnabled) {
+        if (node.name === "regeneratorRuntime" && useRuntimeRegenerator) {
           path.replaceWith(
             this.addDefaultImport(
-              `${this.moduleName}/regenerator`,
+              `${moduleName}/regenerator`,
               "regeneratorRuntime",
             ),
           );
           return;
         }
 
-        if (notPolyfillOrDoesUseBuiltIns) return;
+        if (!injectCoreJS2) return;
 
         if (t.isMemberExpression(parent)) return;
         if (!has(definitions.builtins, node.name)) return;
@@ -121,7 +168,7 @@ export default declare((api, options) => {
 
       // arr[Symbol.iterator]() -> _core.$for.getIterator(arr)
       CallExpression(path) {
-        if (notPolyfillOrDoesUseBuiltIns) return;
+        if (!injectCoreJS2) return;
 
         // we can't compile this
         if (path.node.arguments.length) return;
@@ -146,7 +193,7 @@ export default declare((api, options) => {
 
       // Symbol.iterator in arr -> core.$for.isIterable(arr)
       BinaryExpression(path) {
-        if (notPolyfillOrDoesUseBuiltIns) return;
+        if (!injectCoreJS2) return;
 
         if (path.node.operator !== "in") return;
         if (!path.get("left").matchesPattern("Symbol.iterator")) return;
@@ -165,7 +212,7 @@ export default declare((api, options) => {
       // Array.from -> _core.Array.from
       MemberExpression: {
         enter(path) {
-          if (notPolyfillOrDoesUseBuiltIns) return;
+          if (!injectCoreJS2) return;
           if (!path.isReferenced()) return;
 
           const { node } = path;
@@ -203,7 +250,7 @@ export default declare((api, options) => {
         },
 
         exit(path) {
-          if (notPolyfillOrDoesUseBuiltIns) return;
+          if (!injectCoreJS2) return;
           if (!path.isReferenced()) return;
 
           const { node } = path;
@@ -227,5 +274,3 @@ export default declare((api, options) => {
     },
   };
 });
-
-export { definitions };

packages/babel-plugin-transform-runtime/src/options.json

@@ -1,3 +0,0 @@
-{
-  "plugins": ["transform-runtime", "transform-regenerator"]
-}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/aliased-constructors/input.js

@@ -0,0 +1,7 @@
+obj.constructor === Object;
+obj.constructor === Promise;
+
+Symbol();
+Symbol("test");
+
+new Map();

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/aliased-constructors/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-regenerator"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/aliased-constructors/output.js

@@ -0,0 +1,14 @@
+var _Map = require("@babel/runtime-corejs2/core-js/map");
+
+var _Symbol = require("@babel/runtime-corejs2/core-js/symbol");
+
+var _Promise = require("@babel/runtime-corejs2/core-js/promise");
+
+obj.constructor === Object;
+obj.constructor === _Promise;
+
+_Symbol();
+
+_Symbol("test");
+
+new _Map();

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/catch-all/input.js

@@ -0,0 +1 @@
+Promise.resolve;

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/catch-all/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-regenerator"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/catch-all/output.js

@@ -0,0 +1,3 @@
+var _Promise = require("@babel/runtime-corejs2/core-js/promise");
+
+_Promise.resolve;

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/class/input.js

@@ -0,0 +1 @@
+class Foo {}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/class/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-classes"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/class/output.js

@@ -0,0 +1,7 @@
+var _classCallCheck = require("@babel/runtime-corejs2/helpers/classCallCheck");
+
+let Foo = function Foo() {
+  "use strict";
+
+  _classCallCheck(this, Foo);
+};

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/es6-for-of/input.js

@@ -0,0 +1,3 @@
+for (var i of arr) {
+
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/es6-for-of/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["transform-for-of", ["transform-runtime", { "corejs": 2 }]]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/es6-for-of/output.js

@@ -0,0 +1,24 @@
+var _getIterator = require("@babel/runtime-corejs2/core-js/get-iterator");
+
+var _iteratorNormalCompletion = true;
+var _didIteratorError = false;
+var _iteratorError = undefined;
+
+try {
+  for (var _iterator = _getIterator(arr), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+    var i = _step.value;
+  }
+} catch (err) {
+  _didIteratorError = true;
+  _iteratorError = err;
+} finally {
+  try {
+    if (!_iteratorNormalCompletion && _iterator.return != null) {
+      _iterator.return();
+    }
+  } finally {
+    if (_didIteratorError) {
+      throw _iteratorError;
+    }
+  }
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/full/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-regenerator"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/full/output.mjs

@@ -1,5 +1,5 @@
-import _regeneratorRuntime from "foo/regenerator";
-import _Symbol from "foo/core-js/symbol";
+import _regeneratorRuntime from "@babel/runtime-corejs2/regenerator";
+import _Symbol from "@babel/runtime-corejs2/core-js/symbol";
 
 var _marked =
 /*#__PURE__*/

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/modules-helpers/input.mjs

@@ -0,0 +1,5 @@
+import foo from "foo";
+
+class Example {
+  method() {}
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/modules-helpers/options.json

@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    ["transform-runtime", { "corejs": 2 }],
+    "transform-modules-commonjs",
+    "transform-classes"
+  ]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/modules-helpers/output.js

@@ -0,0 +1,23 @@
+"use strict";
+
+var _interopRequireDefault = require("@babel/runtime-corejs2/helpers/interopRequireDefault");
+
+var _classCallCheck2 = _interopRequireDefault(require("@babel/runtime-corejs2/helpers/classCallCheck"));
+
+var _createClass2 = _interopRequireDefault(require("@babel/runtime-corejs2/helpers/createClass"));
+
+var _foo = _interopRequireDefault(require("foo"));
+
+let Example =
+/*#__PURE__*/
+function () {
+  function Example() {
+    (0, _classCallCheck2.default)(this, Example);
+  }
+
+  (0, _createClass2.default)(Example, [{
+    key: "method",
+    value: function method() {}
+  }]);
+  return Example;
+}();

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/modules/input.mjs

@@ -0,0 +1,4 @@
+import foo from "bar";
+foo;
+
+export * from "mod";

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/modules/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-modules-commonjs"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/modules/output.js

@@ -0,0 +1,28 @@
+"use strict";
+
+var _interopRequireDefault = require("@babel/runtime-corejs2/helpers/interopRequireDefault");
+
+var _Object$defineProperty = require("@babel/runtime-corejs2/core-js/object/define-property");
+
+var _Object$keys = require("@babel/runtime-corejs2/core-js/object/keys");
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+
+var _bar = _interopRequireDefault(require("bar"));
+
+var _mod = require("mod");
+
+_Object$keys(_mod).forEach(function (key) {
+  if (key === "default" || key === "__esModule") return;
+
+  _Object$defineProperty(exports, key, {
+    enumerable: true,
+    get: function () {
+      return _mod[key];
+    }
+  });
+});
+
+_bar.default;

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/no-helpers/input.js

@@ -0,0 +1 @@
+class Foo {}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/no-helpers/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "helpers": false, "corejs": 2 }], "transform-classes"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/no-helpers/output.js

@@ -0,0 +1,7 @@
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+let Foo = function Foo() {
+  "use strict";
+
+  _classCallCheck(this, Foo);
+};

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/regenerator-runtime/input.js

@@ -0,0 +1,2 @@
+void function* () {
+};

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/regenerator-runtime/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-regenerator"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/regenerator-runtime/output.js

@@ -0,0 +1,13 @@
+var _regeneratorRuntime = require("@babel/runtime-corejs2/regenerator");
+
+void
+/*#__PURE__*/
+_regeneratorRuntime.mark(function _callee() {
+  return _regeneratorRuntime.wrap(function _callee$(_context) {
+    while (1) switch (_context.prev = _context.next) {
+      case 0:
+      case "end":
+        return _context.stop();
+    }
+  }, _callee, this);
+});

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/symbol-iterator-in/input.js

@@ -0,0 +1 @@
+Symbol.iterator in Object(arr);

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/symbol-iterator-in/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["transform-runtime", { "corejs": 2 }],
+    "transform-regenerator"
+  ]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/symbol-iterator-in/output.js

@@ -0,0 +1,3 @@
+var _isIterable = require("@babel/runtime-corejs2/core-js/is-iterable");
+
+_isIterable(Object(arr));

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/symbol-iterator/input.js

@@ -0,0 +1 @@
+Symbol.iterator;

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/symbol-iterator/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-regenerator"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/runtime-corejs2/symbol-iterator/output.js

@@ -0,0 +1,3 @@
+var _Symbol$iterator = require("@babel/runtime-corejs2/core-js/symbol/iterator");
+
+_Symbol$iterator;

packages/babel-plugin-transform-runtime/test/fixtures/runtime/aliased-constructors/output.js

@@ -1,14 +1,5 @@
-var _Map = require("@babel/runtime/core-js/map");
-
-var _Symbol = require("@babel/runtime/core-js/symbol");
-
-var _Promise = require("@babel/runtime/core-js/promise");
-
 obj.constructor === Object;
-obj.constructor === _Promise;
-
-_Symbol();
-
-_Symbol("test");
-
-new _Map();
+obj.constructor === Promise;
+Symbol();
+Symbol("test");
+new Map();

packages/babel-plugin-transform-runtime/test/fixtures/runtime/catch-all/output.js

@@ -1,3 +1 @@
-var _Promise = require("@babel/runtime/core-js/promise");
-
-_Promise.resolve;
+Promise.resolve;

packages/babel-plugin-transform-runtime/test/fixtures/runtime/custom-runtime/options.json

@@ -1,3 +0,0 @@
-{
-  "plugins": [["transform-runtime", { "moduleName": "foo" }], "transform-regenerator"]
-}

packages/babel-plugin-transform-runtime/test/fixtures/runtime/es6-for-of/output.js

@@ -1,11 +1,9 @@
-var _getIterator = require("@babel/runtime/core-js/get-iterator");
-
 var _iteratorNormalCompletion = true;
 var _didIteratorError = false;
 var _iteratorError = undefined;
 
 try {
-  for (var _iterator = _getIterator(arr), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+  for (var _iterator = arr[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
     var i = _step.value;
   }
 } catch (err) {

packages/babel-plugin-transform-runtime/test/fixtures/runtime/full/output.mjs

@@ -1,12 +1,11 @@
 import _regeneratorRuntime from "@babel/runtime/regenerator";
-import _Symbol from "@babel/runtime/core-js/symbol";
 
 var _marked =
 /*#__PURE__*/
 _regeneratorRuntime.mark(giveWord);
 
 import foo, * as bar from "someModule";
-export const myWord = _Symbol("abc");
+export const myWord = Symbol("abc");
 export function giveWord() {
   return _regeneratorRuntime.wrap(function giveWord$(_context) {
     while (1) switch (_context.prev = _context.next) {

packages/babel-plugin-transform-runtime/test/fixtures/runtime/modules/output.js

@@ -2,10 +2,6 @@
 
 var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
 
-var _Object$defineProperty = require("@babel/runtime/core-js/object/define-property");
-
-var _Object$keys = require("@babel/runtime/core-js/object/keys");
-
 Object.defineProperty(exports, "__esModule", {
   value: true
 });
@@ -14,15 +10,13 @@ var _bar = _interopRequireDefault(require("bar"));
 
 var _mod = require("mod");
 
-_Object$keys(_mod).forEach(function (key) {
+Object.keys(_mod).forEach(function (key) {
   if (key === "default" || key === "__esModule") return;
-
-  _Object$defineProperty(exports, key, {
+  Object.defineProperty(exports, key, {
     enumerable: true,
     get: function () {
       return _mod[key];
     }
   });
 });
-
 _bar.default;

packages/babel-plugin-transform-runtime/test/fixtures/runtime/symbol-iterator-in/output.js

@@ -1,3 +1 @@
-var _isIterable = require("@babel/runtime/core-js/is-iterable");
-
-_isIterable(Object(arr));
+Symbol.iterator in Object(arr);

packages/babel-plugin-transform-runtime/test/fixtures/runtime/symbol-iterator/output.js

@@ -1,3 +1 @@
-var _Symbol$iterator = require("@babel/runtime/core-js/symbol/iterator");
-
-_Symbol$iterator;
+Symbol.iterator;

packages/babel-plugin-transform-runtime/test/fixtures/use-options/corejs-useES6Modules/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2, "useESModules": true }], "transform-classes"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/use-options/corejs-useES6Modules/output.js

@@ -0,0 +1,23 @@
+var _classCallCheck = require("@babel/runtime-corejs2/helpers/esm/classCallCheck");
+
+var _possibleConstructorReturn = require("@babel/runtime-corejs2/helpers/esm/possibleConstructorReturn");
+
+var _getPrototypeOf = require("@babel/runtime-corejs2/helpers/esm/getPrototypeOf");
+
+var _inherits = require("@babel/runtime-corejs2/helpers/esm/inherits");
+
+let Foo =
+/*#__PURE__*/
+function (_Bar) {
+  "use strict";
+
+  _inherits(Foo, _Bar);
+
+  function Foo() {
+    _classCallCheck(this, Foo);
+
+    return _possibleConstructorReturn(this, _getPrototypeOf(Foo).apply(this, arguments));
+  }
+
+  return Foo;
+}(Bar);

packages/babel-plugin-transform-runtime/test/fixtures/use-options/corejs/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": [["transform-runtime", { "corejs": 2 }], "transform-classes"]
+}

packages/babel-plugin-transform-runtime/test/fixtures/use-options/corejs/output.js

@@ -0,0 +1,23 @@
+var _classCallCheck = require("@babel/runtime-corejs2/helpers/classCallCheck");
+
+var _possibleConstructorReturn = require("@babel/runtime-corejs2/helpers/possibleConstructorReturn");
+
+var _getPrototypeOf = require("@babel/runtime-corejs2/helpers/getPrototypeOf");
+
+var _inherits = require("@babel/runtime-corejs2/helpers/inherits");
+
+let Foo =
+/*#__PURE__*/
+function (_Bar) {
+  "use strict";
+
+  _inherits(Foo, _Bar);
+
+  function Foo() {
+    _classCallCheck(this, Foo);
+
+    return _possibleConstructorReturn(this, _getPrototypeOf(Foo).apply(this, arguments));
+  }
+
+  return Foo;
+}(Bar);

packages/babel-plugin-transform-runtime/test/fixtures/use-options/useBuiltIns-useESModules/options.json

@@ -1,3 +0,0 @@
-{
-  "plugins": [["transform-runtime", { "useBuiltIns": true, "useESModules": true }], "transform-classes"]
-}

packages/babel-plugin-transform-runtime/test/fixtures/use-options/useBuiltIns-useESModules/output.js

@@ -1,23 +0,0 @@
-var _classCallCheck = require("@babel/runtime/helpers/builtin/es6/classCallCheck");
-
-var _possibleConstructorReturn = require("@babel/runtime/helpers/builtin/es6/possibleConstructorReturn");
-
-var _getPrototypeOf = require("@babel/runtime/helpers/builtin/es6/getPrototypeOf");
-
-var _inherits = require("@babel/runtime/helpers/builtin/es6/inherits");
-
-let Foo =
-/*#__PURE__*/
-function (_Bar) {
-  "use strict";
-
-  _inherits(Foo, _Bar);
-
-  function Foo() {
-    _classCallCheck(this, Foo);
-
-    return _possibleConstructorReturn(this, _getPrototypeOf(Foo).apply(this, arguments));
-  }
-
-  return Foo;
-}(Bar);

packages/babel-plugin-transform-runtime/test/fixtures/use-options/useBuiltIns/options.json

@@ -1,3 +0,0 @@
-{
-  "plugins": [["transform-runtime", { "useBuiltIns": true }], "transform-classes"]
-}

packages/babel-plugin-transform-runtime/test/fixtures/use-options/useBuiltIns/output.js

@@ -1,23 +0,0 @@
-var _classCallCheck = require("@babel/runtime/helpers/builtin/classCallCheck");
-
-var _possibleConstructorReturn = require("@babel/runtime/helpers/builtin/possibleConstructorReturn");
-
-var _getPrototypeOf = require("@babel/runtime/helpers/builtin/getPrototypeOf");
-
-var _inherits = require("@babel/runtime/helpers/builtin/inherits");
-
-let Foo =
-/*#__PURE__*/
-function (_Bar) {
-  "use strict";
-
-  _inherits(Foo, _Bar);
-
-  function Foo() {
-    _classCallCheck(this, Foo);
-
-    return _possibleConstructorReturn(this, _getPrototypeOf(Foo).apply(this, arguments));
-  }
-
-  return Foo;
-}(Bar);

packages/babel-plugin-transform-runtime/test/fixtures/use-options/useESModules/output.js

@@ -1,10 +1,10 @@
-var _classCallCheck = require("@babel/runtime/helpers/es6/classCallCheck");
+var _classCallCheck = require("@babel/runtime/helpers/esm/classCallCheck");
 
-var _possibleConstructorReturn = require("@babel/runtime/helpers/es6/possibleConstructorReturn");
+var _possibleConstructorReturn = require("@babel/runtime/helpers/esm/possibleConstructorReturn");
 
-var _getPrototypeOf = require("@babel/runtime/helpers/es6/getPrototypeOf");
+var _getPrototypeOf = require("@babel/runtime/helpers/esm/getPrototypeOf");
 
-var _inherits = require("@babel/runtime/helpers/es6/inherits");
+var _inherits = require("@babel/runtime/helpers/esm/inherits");
 
 let Foo =
 /*#__PURE__*/

packages/babel-runtime-corejs2/.npmignore

@@ -0,0 +1,3 @@
+src
+test
+*.log

packages/babel-runtime-corejs2/README.md

@@ -0,0 +1,19 @@
+# @babel/runtime-corejs2
+
+> babel's modular runtime helpers with core-js@2 polyfilling
+
+See our website [@babel/runtime-corejs2](https://babeljs.io/docs/en/next/babel-runtime-corejs2.html) for more information.
+
+## Install
+
+Using npm:
+
+```sh
+npm install --save-dev @babel/runtime-corejs2
+```
+
+or using yarn:
+
+```sh
+yarn add @babel/runtime-corejs2 --dev
+```

packages/babel-runtime-corejs2/helpers/iterableToArray.js

@@ -0,0 +1,9 @@
+var _Array$from = require("../core-js/array/from");
+
+var _isIterable = require("../core-js/is-iterable");
+
+function _iterableToArray(iter) {
+  if (_isIterable(Object(iter)) || Object.prototype.toString.call(iter) === "[object Arguments]") return _Array$from(iter);
+}
+
+module.exports = _iterableToArray;

packages/babel-runtime-corejs2/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "@babel/runtime-corejs2",
+  "version": "7.0.0-beta.51",
+  "description": "babel's modular runtime helpers with core-js@2 polyfilling",
+  "license": "MIT",
+  "repository": "https://github.com/babel/babel/tree/master/packages/babel-runtime-corejs2",
+  "author": "Sebastian McKenzie <sebmck@gmail.com>",
+  "dependencies": {
+    "core-js": "^2.5.7",
+    "regenerator-runtime": "^0.12.0"
+  }
+}

packages/babel-runtime-corejs2/regenerator/index.js

@@ -0,0 +1 @@
+module.exports = require("regenerator-runtime");

packages/babel-runtime/.npmignore

@@ -1,4 +1,3 @@
-scripts
 src
 test
 *.log

packages/babel-runtime/README.md

@@ -1,6 +1,6 @@
 # @babel/runtime
 
-> babel selfContained runtime
+> babel's modular runtime helpers
 
 See our website [@babel/runtime](https://babeljs.io/docs/en/next/babel-runtime.html) for more information.
 

packages/babel-runtime/core-js.js

@@ -1 +0,0 @@
-module.exports = require("core-js/library");

packages/babel-runtime/helpers/builtin/iterableToArray.js

@@ -1,5 +0,0 @@
-function _iterableToArray(iter) {
-  if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
-}
-
-module.exports = _iterableToArray;

packages/babel-runtime/helpers/iterableToArray.js

@@ -1,9 +1,5 @@
-var _Array$from = require("../core-js/array/from");
-
-var _isIterable = require("../core-js/is-iterable");
-
 function _iterableToArray(iter) {
-  if (_isIterable(Object(iter)) || Object.prototype.toString.call(iter) === "[object Arguments]") return _Array$from(iter);
+  if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
 }
 
 module.exports = _iterableToArray;

packages/babel-runtime/package.json

@@ -1,19 +1,11 @@
 {
   "name": "@babel/runtime",
   "version": "7.0.0-beta.55",
-  "description": "babel selfContained runtime",
+  "description": "babel's modular runtime helpers",
   "license": "MIT",
   "repository": "https://github.com/babel/babel/tree/master/packages/babel-runtime",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "dependencies": {
-    "core-js": "^2.5.7",
     "regenerator-runtime": "^0.12.0"
-  },
-  "devDependencies": {
-    "@babel/core": "7.0.0-beta.55",
-    "@babel/helpers": "7.0.0-beta.55",
-    "@babel/plugin-transform-runtime": "7.0.0-beta.55",
-    "@babel/preset-env": "7.0.0-beta.55",
-    "@babel/types": "7.0.0-beta.55"
   }
 }

packages/babel-runtime/scripts/build-dist.js

@@ -1,165 +0,0 @@
-"use strict";
-
-const outputFile = require("output-file-sync");
-const coreDefinitions = require("@babel/plugin-transform-runtime").definitions;
-const helpers = require("@babel/helpers");
-const babel = require("@babel/core");
-const t = require("@babel/types");
-
-const paths = ["is-iterable", "get-iterator"];
-
-Object.keys(coreDefinitions.builtins).forEach((key) => {
-  const path = coreDefinitions.builtins[key];
-  paths.push(path);
-});
-
-Object.keys(coreDefinitions.methods).forEach((key) => {
-  const props = coreDefinitions.methods[key];
-  Object.keys(props).forEach((key2) => {
-    const path = props[key2];
-    paths.push(path);
-  });
-});
-
-paths.forEach(function(path) {
-  writeFile(
-    "core-js/" + path + ".js",
-    defaultify(`require("core-js/library/fn/${path}")`)
-  );
-});
-
-function relative(filename) {
-  return `${__dirname}/../${filename}`;
-}
-
-function defaultify(name) {
-  return `module.exports = ${name};`;
-}
-
-function writeRootFile(filename, content) {
-  filename = relative(filename);
-  outputFile(filename, content);
-}
-
-function writeFile(filename, content) {
-  return writeRootFile(filename, content);
-}
-
-function makeTransformOpts(modules, useBuiltIns) {
-  const opts = {
-    presets: [[require("@babel/preset-env"), { modules: false }]],
-
-    plugins: [
-      [
-        require("@babel/plugin-transform-runtime"),
-        { useBuiltIns, useESModules: modules === false },
-      ],
-    ],
-  };
-  return opts;
-}
-
-function adjustImportPath(node, relativePath) {
-  if (helpers.list.indexOf(node.value) >= 0) {
-    node.value = `./${node.value}`;
-  } else {
-    node.value = node.value.replace(/^@babel\/runtime/, relativePath);
-  }
-}
-
-function buildRuntimeRewritePlugin(relativePath, helperName, dependencies) {
-  return {
-    pre(file) {
-      const original = file.get("helperGenerator");
-      file.set("helperGenerator", (name) => {
-        // make sure that helpers won't insert circular references to themselves
-        if (name === helperName) return false;
-
-        return original(name);
-      });
-    },
-    visitor: {
-      ImportDeclaration(path) {
-        adjustImportPath(path.get("source").node, relativePath);
-      },
-      CallExpression(path) {
-        if (
-          !path.get("callee").isIdentifier({ name: "require" }) ||
-          path.get("arguments").length !== 1 ||
-          !path.get("arguments")[0].isStringLiteral()
-        ) {
-          return;
-        }
-
-        // replace any reference to @babel/runtime and other helpers
-        // with a relative path
-        adjustImportPath(path.get("arguments")[0].node, relativePath);
-      },
-    },
-  };
-}
-
-function buildRequireCall(id, dep) {
-  return t.variableDeclaration("var", [
-    t.variableDeclarator(
-      id,
-      t.callExpression(t.identifier("require"), [t.stringLiteral(dep)])
-    )
-  ]);
-}
-
-function buildHelper(helperName, modules, useBuiltIns) {
-  const id =
-    modules === "commonjs"
-      ? t.memberExpression(t.identifier("module"), t.identifier("exports"))
-      : null;
-  const sourceType = modules === "commonjs" ? "script" : "module";
-
-  const tree = t.program([], [], sourceType);
-  const dependencies = {};
-  let bindings = null;
-
-  if (modules === "commonjs") {
-    bindings = [];
-    for (const dep of helpers.getDependencies(helperName)) {
-      const id = dependencies[dep] = t.identifier(t.toIdentifier(dep));
-      tree.body.push(buildRequireCall(id, dep));
-      bindings.push(id.name);
-    }
-  }
-
-  const helper = helpers.get(
-    helperName,
-    dep => dependencies[dep],
-    id,
-    bindings
-  );
-  tree.body.push.apply(tree.body, helper.nodes);
-
-  const transformOpts = makeTransformOpts(modules, useBuiltIns);
-
-  const relative = useBuiltIns ? "../.." : "..";
-  
-  return babel.transformFromAst(tree, null, {
-    presets: transformOpts.presets,
-    plugins: transformOpts.plugins.concat([
-      buildRuntimeRewritePlugin(
-        modules === false ? `../${relative}` : relative,
-        helperName
-      ),
-    ]),
-  }).code;
-}
-
-for (const modules of ["commonjs", false]) {
-  for (const builtin of [false, true]) {
-    const dirname = `helpers/${builtin ? "builtin/" : ""}${!modules ? "es6/" : ""}`;
-
-    for (const helperName of helpers.list) {
-      writeFile(
-        `${dirname}${helperName}.js`,
-        buildHelper(helperName, modules, builtin)
-      );
-    }
-  }
-}