__exportStar in tsc output not transpiled to esm

[nayeemrmn]

If a node typescript library has the following content:

export const foo = 1;
export * from './bar'

and the author transpiles it using tsc targeting cjs, they get something resembling:

var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    var desc = Object.getOwnPropertyDescriptor(m, k);
    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
      desc = { enumerable: true, get: function() { return m[k]; } };
    }
    Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    o[k2] = m[k];
}));
var __exportStar = (this && this.__exportStar) || function(m, exports) {
    for (var p in m) if (p !== "default" && !Object.prototype.hasOwnProperty.call(exports, p)) __createBinding(exports, m, p);
};
Object.defineProperty(exports, "foo", { value: 1 });
__exportStar(require("./bar"), exports);

and they upload that to npm.

Understandably, esm.sh will recognise and generate an esm export for the Object.defineProperty(exports, "foo", { value: 1 }) but not the __exportStar((require("./bar"), exports). Despite the non-exactness I think it could be worth transpiling all instances of

__exportStar(require("<specifier>"), exports);

to

export * from "<specifier>";

As described above, this will enable a lot more modules from the Node/TS ecosystem to run correctly in browsers and Deno @ije.

Reproduction / example library (from @sinclairzx81)

• https://github.com/sinclairzx81/typebox/blob/0.24.27/src/value/index.ts
  • is transpiled with tsc targetting cjs / es2020 to
• https://pastebin.com/C3iqt2Ea
  • which is uploaded to npm and transformed by esm.sh to:
• https://esm.sh/v89/@sinclair/typebox@0.24.27/es2022/value/index.js
  • which doesn't contain the export * from './value' in the original source.

As a result, import { Value } from "https://esm.sh/@sinclair/typebox@0.24.27/value" gives the following runtime error in Deno:

error: Uncaught SyntaxError: The requested module 'https://esm.sh/@sinclair/typebox@0.24.27/value' does not provide an export named 'Value'
import { Value } from "https://esm.sh/@sinclair/typebox@0.24.27/value";
         ^

[ije]

i added tslib.__exportStar support in https://github.com/ije/esm.sh/blob/b81ea0f66c41a61f6db8666de3748ea0c629919f/packages/esm-cjs-lexer/src/test.rs#L597, but didn't consider the bundled __exportStar

[nayeemrmn]

@ije For some reason this fix can't be observed in https://esm.sh/v89/@sinclair/typebox@0.24.27/deno/compiler.js even though it can be observed in https://esm.sh/v89/@sinclair/typebox@0.24.27/es2022/compiler.js.

Whereas it works for both https://esm.sh/v89/@sinclair/typebox@0.24.27/es2022/value.js and https://esm.sh/v89/@sinclair/typebox@0.24.27/deno/value.js.

Any idea?