review

packages/babel-helper-remap-async-to-generator/src/index.ts

@@ -12,7 +12,7 @@ const {
 } = t;
 
 const awaitVisitor = traverse.visitors.merge<{
- wrapAwait: t.Expression | string;
+ wrapAwait: t.Expression | (() => t.Expression);
 }>([
  {
  ArrowFunctionExpression(path) {
@@ -26,8 +26,8 @@ const awaitVisitor = traverse.visitors.merge<{
  yieldExpression(
  wrapAwait
  ? callExpression(
- typeof wrapAwait === "string"
- ? path.hub.addHelper(wrapAwait)
+ typeof wrapAwait === "function"
+ ? wrapAwait()
  : cloneNode(wrapAwait),
  [argument.node],
  )
@@ -42,9 +42,9 @@ const awaitVisitor = traverse.visitors.merge<{
 export default function (
  path: NodePath<t.Function>,
  helpers: {
- wrapAsync: t.Expression | string;
- wrapAwait?: t.Expression | string;
- callAsync?: string;
+ wrapAsync: t.Expression | (() => t.Expression);
+ wrapAwait?: t.Expression | (() => t.Expression);
+ callAsync?: () => t.Expression;
  },
  noNewArrows?: boolean,
  ignoreFunctionLength?: boolean,

packages/babel-helper-wrap-function/src/index.ts

@@ -75,10 +75,12 @@ const buildWrapper = template.statement(`
  replacements: Parameters<ReturnType<typeof template.expression>>[0],
 ) => t.FunctionDeclaration;
 
+const wrappedFns = new WeakMap<t.CallExpression, t.Function>();
+
 function markCallWrapped(path: NodePath<t.Function>) {
- (path.get("body.body.0.argument") as NodePath).setData(
- "babel-helper-wrap-function_wrapped_function",
- (path.get("body.body.0.argument.callee") as NodePath).node,
+ wrappedFns.set(
+ (path.get("body.body.0.argument") as NodePath<t.CallExpression>).node,
+ (path.get("body.body.0.argument.callee") as NodePath<t.Function>).node,
  );
 }
 
@@ -198,11 +200,11 @@ function plainFunction(
 
 export default function wrapFunction(
  path: NodePath<t.Function>,
- callId: t.Expression | string,
+ callId: t.Expression | (() => t.Expression),
  // TODO(Babel 8): Consider defaulting to false for spec compliance
  noNewArrows: boolean = true,
  ignoreFunctionLength: boolean = false,
- callAsync?: string,
+ callAsync?: () => t.Expression,
 ) {
  if (callAsync) {
  if (path.isMethod()) {
@@ -215,11 +217,7 @@ export default function wrapFunction(
  blockStatement(body.body),
  true,
  );
- body.body = [
- returnStatement(
- callExpression(path.hub.addHelper(callAsync), [container]),
- ),
- ];
+ body.body = [returnStatement(callExpression(callAsync(), [container]))];
 
  // Regardless of whether or not the wrapped function is an async method
  // or generator the outer function should not be
@@ -239,7 +237,9 @@ export default function wrapFunction(
  let path2 = path.arrowFunctionToExpression({ noNewArrows });
  if (!process.env.BABEL_8_BREAKING) {
  // arrowFunctionToExpression returns undefined in @babel/traverse < 7.18.10
- path2 ??= path;
+ path2 ??= path as unknown as NodePath<
+ t.FunctionDeclaration | t.FunctionExpression | t.CallExpression
+ >;
  }
  // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion
  node = path2.node as
@@ -254,7 +254,7 @@ export default function wrapFunction(
  let built = node;
  if (!isCallExpression(node)) {
  functionId = node.id;
- built = callExpression(path.hub.addHelper(callAsync), [
+ built = callExpression(callAsync(), [
  functionExpression(null, node.params, node.body, node.generator),
  identifier("this"),
  identifier("arguments"),
@@ -294,7 +294,7 @@ export default function wrapFunction(
  } else {
  // we can omit this wrapper as the conditions it protects for do not apply
  path.replaceWith(
- callExpression(path.hub.addHelper(callId as string), [
+ callExpression((callId as () => t.Expression)(), [
  node as t.FunctionExpression,
  ]),
  );
@@ -322,10 +322,8 @@ export function buildOnCallExpression(helperName: string) {
  if (!state.availableHelper(helperName)) {
  return;
  }
- if (path.parentPath.isCallExpression()) {
- const wrappedFn = path.parentPath.getData(
- "babel-helper-wrap-function_wrapped_function",
- );
+ if (isCallExpression(path.parent)) {
+ const wrappedFn = wrappedFns.get(path.parent);
 
  if (!wrappedFn || wrappedFn === path.node.callee) return;
 

packages/babel-helpers/src/helpers.ts

@@ -34,41 +34,6 @@ helpers.wrapAsyncGenerator = helper("7.0.0-beta.0")`
  }
 `;
 
-helpers.asyncToGenerator = helper("7.0.0-beta.0")`
- function asyncGeneratorStep(gen, resolve, reject, _next, _throw, key, arg) {
- try {
- var info = gen[key](arg);
- var value = info.value;
- } catch (error) {
- reject(error);
- return;
- }
-
- if (info.done) {
- resolve(value);
- } else {
- Promise.resolve(value).then(_next, _throw);
- }
- }
-
- export default function _asyncToGenerator(fn) {
- return function () {
- var self = this, args = arguments;
- return new Promise(function (resolve, reject) {
- var gen = fn.apply(self, args);
- function _next(value) {
- asyncGeneratorStep(gen, resolve, reject, _next, _throw, "next", value);
- }
- function _throw(err) {
- asyncGeneratorStep(gen, resolve, reject, _next, _throw, "throw", err);
- }
-
- _next(undefined);
- });
- };
- }
-`;
-
 helpers.callAsyncGenerator = helper("7.23.0")`
  import AsyncGenerator from "AsyncGenerator";
 
@@ -77,9 +42,9 @@ helpers.callAsyncGenerator = helper("7.23.0")`
  }
 `;
 
-helpers.asyncToGenerator2 = helper("7.23.0")`
+helpers.asyncToGenerator = helper("7.23.0")`
  import callAsync from "callAsync";
- export default function _asyncToGenerator2(fn) {
+ export default function _asyncToGenerator(fn) {
  return function () {
  return callAsync(fn, this, arguments);
  };
@@ -915,31 +880,6 @@ helpers.callSkipFirstGeneratorNext = helper("7.23.0")`
  }
 `;
 
-helpers.toPrimitive = helper("7.1.5")`
- export default function _toPrimitive(
- input,
- hint /*: "default" | "string" | "number" | void */
- ) {
- if (typeof input !== "object" || input === null) return input;
- var prim = input[Symbol.toPrimitive];
- if (prim !== undefined) {
- var res = prim.call(input, hint || "default");
- if (typeof res !== "object") return res;
- throw new TypeError("@@toPrimitive must return a primitive value.");
- }
- return (hint === "string" ? String : Number)(input);
- }
-`;
-
-helpers.toPropertyKey = helper("7.1.5")`
- import toPrimitive from "toPrimitive";
-
- export default function _toPropertyKey(arg) {
- var key = toPrimitive(arg, "string");
- return typeof key === "symbol" ? key : String(key);
- }
-`;
-
 /**
  * Add a helper that will throw a useful error if the transform fails to detect the class
  * property assignment, so users know something failed.

packages/babel-plugin-proposal-function-sent/src/index.ts

@@ -46,42 +46,44 @@ export default declare(api => {
  name: "proposal-function-sent",
  inherits: syntaxFunctionSent,
 
- visitor: {
- ...wrapFunction.buildOnCallExpression("callSkipFirstGeneratorNext"),
- MetaProperty(path, state) {
- if (!isFunctionSent(path.node)) return;
+ visitor: api.traverse.visitors.merge([
+ wrapFunction.buildOnCallExpression("callSkipFirstGeneratorNext"),
+ {
+ MetaProperty(path, state) {
+ if (!isFunctionSent(path.node)) return;
 
- const fnPath = path.getFunctionParent();
+  const fnPath = path.getFunctionParent();
 
- if (!fnPath.node.generator) {
- throw new Error("Parent generator function not found");
- }
+  if (!fnPath.node.generator) {
+  throw new Error("Parent generator function not found");
+  }
 
- const sentId = path.scope.generateUid("function.sent");
+  const sentId = path.scope.generateUid("function.sent");
 
- fnPath.traverse(yieldVisitor, { sentId });
- // @ts-expect-error A generator must not be an arrow function
- fnPath.node.body.body.unshift(
- t.variableDeclaration("let", [
- t.variableDeclarator(t.identifier(sentId), t.yieldExpression()),
- ]),
- );
-
- if (state.availableHelper("callSkipFirstGeneratorNext")) {
- wrapFunction.default(
- fnPath,
- "skipFirstGeneratorNext",
- undefined,
- undefined,
- "callSkipFirstGeneratorNext",
- );
- } else {
- wrapFunction.default(
- fnPath,
- state.addHelper("skipFirstGeneratorNext"),
+ fnPath.traverse(yieldVisitor, { sentId });
+ // @ts-expect-error A generator must not be an arrow function
+ fnPath.node.body.body.unshift(
+ t.variableDeclaration("let", [
+ t.variableDeclarator(t.identifier(sentId), t.yieldExpression()),
+ ]),
  );
- }
+
+ if (state.availableHelper("callSkipFirstGeneratorNext")) {
+ wrapFunction.default(
+ fnPath,
+ () => state.addHelper("skipFirstGeneratorNext"),
+ undefined,
+ undefined,
+ () => state.addHelper("callSkipFirstGeneratorNext"),
+ );
+ } else {
+ wrapFunction.default(
+ fnPath,
+ state.addHelper("skipFirstGeneratorNext"),
+ );
+ }
+ },
  },
- },
+ ]),
  };
 });

packages/babel-plugin-transform-async-generator-functions/src/index.ts

@@ -93,9 +93,9 @@ export default declare(api => {
  path,
  state.availableHelper("callAsyncGenerator")
  ? {
- wrapAsync: "wrapAsyncGenerator",
- wrapAwait: "awaitAsyncGenerator",
- callAsync: "callAsyncGenerator",
+ wrapAsync: () => state.addHelper("wrapAsyncGenerator"),
+ wrapAwait: () => state.addHelper("awaitAsyncGenerator"),
+ callAsync: () => state.addHelper("callAsyncGenerator"),
  }
  : {
  wrapAsync: state.addHelper("wrapAsyncGenerator"),
@@ -114,18 +114,20 @@ export default declare(api => {
  : // eslint-disable-next-line no-restricted-globals
  require("@babel/plugin-syntax-async-generators").default,
 
- visitor: {
- ...remapAsyncToGenerator.buildOnCallExpression("callAsyncGenerator"),
- Program(path, state) {
- // We need to traverse the ast here (instead of just vising Function
- // in the top level visitor) because for-await needs to run before the
- // async-to-generator plugin. This is because for-await is transpiled
- // using "await" expressions, which are then converted to "yield".
- //
- // This is bad for performance, but plugin ordering will allow as to
- // directly visit Function in the top level visitor.
- path.traverse(visitor, state);
+ visitor: api.traverse.visitors.merge([
+ remapAsyncToGenerator.buildOnCallExpression("callAsyncGenerator"),
+ {
+ Program(path, state) {
+ // We need to traverse the ast here (instead of just vising Function
+ // in the top level visitor) because for-await needs to run before the
+ // async-to-generator plugin. This is because for-await is transpiled
+ // using "await" expressions, which are then converted to "yield".
+ //
+ // This is bad for performance, but plugin ordering will allow as to
+ // directly visit Function in the top level visitor.
+ path.traverse(visitor, state);
+ },
  },
- },
+ ]),
  };
 });

packages/babel-plugin-transform-async-generator-functions/test/fixtures/for-await/async-arrow/output.js

@@ -1,4 +1,4 @@
-/*#__PURE__*/babelHelpers.asyncToGenerator2(function* () {
+/*#__PURE__*/babelHelpers.asyncToGenerator(function* () {
  var _iteratorAbruptCompletion = false;
  var _didIteratorError = false;
  var _iteratorError;

packages/babel-plugin-transform-async-generator-functions/test/fixtures/for-await/lhs-member-expression/output.js

@@ -1,4 +1,4 @@
-babelHelpers.asyncToGenerator2(function* () {
+babelHelpers.asyncToGenerator(function* () {
  var _iteratorAbruptCompletion = false;
  var _didIteratorError = false;
  var _iteratorError;

packages/babel-plugin-transform-async-generator-functions/test/fixtures/for-await/re-declare-var-in-init-body/output.js

@@ -1,4 +1,4 @@
-/*#__PURE__*/babelHelpers.asyncToGenerator2(function* () {
+/*#__PURE__*/babelHelpers.asyncToGenerator(function* () {
  var _iteratorAbruptCompletion = false;
  var _didIteratorError = false;
  var _iteratorError;

packages/babel-plugin-transform-async-generator-functions/test/fixtures/nested/arrows-in-declaration/output.js

@@ -5,7 +5,7 @@ function g() {
  function f() {
  () => this;
  }
- /*#__PURE__*/babelHelpers.asyncToGenerator2(function* () {
+ /*#__PURE__*/babelHelpers.asyncToGenerator(function* () {
  _this;
  yield 1;
  });

packages/babel-plugin-transform-async-generator-functions/test/fixtures/nested/async-in-params/output.js

@@ -1,5 +1,5 @@
 function g() {
- return babelHelpers.callAsyncGenerator(function* (x = /*#__PURE__*/babelHelpers.asyncToGenerator2(function* () {
+ return babelHelpers.callAsyncGenerator(function* (x = /*#__PURE__*/babelHelpers.asyncToGenerator(function* () {
  yield 1;
  })) {
  yield babelHelpers.awaitAsyncGenerator(2);