@parcel/transformer-typescript-types does not work

[ranisalt]

🐛 bug report

🎛 Configuration (.babelrc, package.json, cli command)

package.json:

{
	"source": "src/index.ts",
	"module": "dist/index.js",
	"types": "dist/index.d.ts",
}

src/index.ts

export * from './src/components';

CLI: parcel build index.ts

🤔 Expected Behavior

It should build.

😯 Current Behavior

@parcel/transformer-typescript-types: node.exportClause.elements is not iterable
TypeError: node.exportClause.elements is not iterable
    at visit (/home/rsa/skyfall/frontend/node_modules/@parcel/transformer-typescript-types/lib/collect.js:66:47)
    at visitNodes (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80382:48)
    at Object.visitEachChild (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80739:56)
    at visit (/home/rsa/skyfall/frontend/node_modules/@parcel/transformer-typescript-types/lib/collect.js:112:15)
    at visitNode (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80329:23)
    at Object.visitEachChild (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80737:222)
    at visit (/home/rsa/skyfall/frontend/node_modules/@parcel/transformer-typescript-types/lib/collect.js:112:15)
    at visitNodes (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80382:48)
    at visitLexicalEnvironment (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80422:22)
    at Object.visitEachChild (/home/rsa/skyfall/frontend/node_modules/typescript/lib/typescript.js:80809:55)

💁 Possible Solution

🔦 Context

I just want to build this with types.

💻 Code Sample

🌍 Your Environment

Software	Version(s)
Parcel	parcel@2.0.0-nightly.579
Node	v15.9.0
npm/Yarn	1.22.10
Operating System	Arch Linux

[mischnic]

I've tried this:

{
	"source": "index.ts",
	"types": "dist/index.d.ts",
	"scripts": {
		"build": "parcel build . --no-cache"
	},
	"dependencies": {
		"parcel": "2.0.0-nightly.579",
		"typescript": "^4.1.5"
	}
}

// index.ts
export * from './components';

// components.ts
export type Foo = string;

but it builds fine. Looks like some code in ./src/components is triggering that error (or you have a different typescript version)?

[ranisalt]

My src/components/index.ts had an export * as Icons from './Icons', and Icons.tsx exported several React components. That alone created issues with the babel transformer, a cryptic error message that unfortunately I didn't save, so I have been using the typescript-tsc which goes past that. I don't have the files in hand now, but maybe that's related?

[tia-svazquez]

I have exactly the same issue as @ranisalt when trying to export an Icons file on my index.ts.

[penx]

Confirmed I ran in to this issue and it goes away if I comment out my usage of export * as

[gruszkakarol]

I run into this issue as well whenever using export * as foo from "./foo" or export * from "./foo" syntax.

[anhpham1509]

Confirmed the same problems with export * as something from "./somewhere"

Also, the type declarations are bundled into one file incorrectly.

[anhpham1509]

#7315

I found this PR, might be it helps to sort things out.

[astegmaier]

I tested, and #7315 doesn't address this issue, unfortunately (although it does fix #7306).

I can confirm the repro - export * as something from "./somewhere" causes the issue above. Its because we assume that if node.exportClause is defined, it will have an elements property.

parcel/packages/transformers/typescript-types/src/collect.js

Lines 58 to 60 in 1069398

	if (ts.isExportDeclaration(node)) {
	if (node.exportClause) {
	for (let element of node.exportClause.elements) {

But if you look at the relevant typescript API types, "exportsClause" could be a NamespaceExport type, in which case there will be no elements property

ExportDeclaration (code)

    export interface ExportDeclaration extends DeclarationStatement, JSDocContainer {
        // ...
        /** Will not be assigned in the case of `export * from "foo";` */
        readonly exportClause?: NamedExportBindings;
        // ...
    }

NamedExportBindings (code)

export type NamedExportBindings =
    | NamespaceExport
    | NamedExports
    ;

NamespaceExport (code)

    export interface NamespaceExport extends NamedDeclaration {
        readonly kind: SyntaxKind.NamespaceExport;
        readonly parent: ExportDeclaration;
        readonly name: Identifier
    }

So the issue is that we don't handle this case, probably because it was released after the initial implementation of @parcel/transformer-typescript-types - in Typescript 3.8 (Feb 2020)

[code-and-such]

a reasonable workaround

import * as StringUtils2 from './utils/StringUtils';
export const StringUtils = {
  ...StringUtils2
}
``

[jy95]

Still an issue with "@parcel/transformer-typescript-types": "^2.3.2" unfortunately

[oe]

Still an issue with "@parcel/transformer-typescript-types": "^2.4.0"

[lucassarcanjo]

Any updates about this issue? Same error with "@parcel/transformer-typescript-types": "^2.4.1"

[yuuk]

Same error with "@parcel/transformer-typescript-types": "^2.5.0"

[Remeic]

@yuuk have you found some way to solve the issue?

[yuuk]

@yuuk have you found some way to solve the issue?

didn't yet

[bricejar]

Same issue here.

[pedromcunha]

You can get it working by doing this:

export { default as StringUtils2 } from './utils/StringUtils'

[kkirby]

Preliminary results show that changing the line if (node.exportClause) { to if (node.exportClause && node.exportClause.elements) { seems to work as expected. It's correctly exporting all export * as Module from '...'; I can make a PR if anyone doesn't see anything wrong with that.

[ivanbanov]

As bizarre as it can sound, I was getting exact the same error because of the name of my file, in the project I have some utils, and one of them is called utils/react.ts, apparently parcel does not like the idea and throws the error 😅

🚨 Build failed.

@parcel/transformer-typescript-types: Got unexpected undefined

[ivanbanov]

Oh ok, seems like my issue was already reported #7669 👌

[PavlMais]

After adding tsconfig.json everything works

[camdub]

I'm still seeing this issue.

I saw a PR (#8532) from @kkirby that was closed without merging. Is there a reason that fix didn't go through?

[kkirby]

@camdub I closed that for the following reason: #8532 (comment)

[camdub]

Ah, I missed that comment, thanks!

So at this point this is still an open issue?

[kkirby]

Yep.

[bergwerf]

I'm a bit stumped this issue is still open. I'm essentially forced to either switch to another bundler (maybe Rollup) or remove the use of import * as ... from ..., which I just can't.

[Taelar]

I confirm this is still an issue, using :
"typescript": "^4.9.3"
"@parcel/transformer-typescript-types": "^2.10.3",
(I tried to upgrade to TS 5.3 but it did not seem to fix the problem)

It seems to happen when exporting types :

// MyTypes.ts
export interface Car { }
export interface Bus{ }

// index.ts
export * as Vehicles from './MyTypes.ts'

This raises the error TypeError: node.exportClause.elements is not iterable

If anyone is interested, here's my workaround. It's far from great but it works in my case :

// index.ts
import type { Car, Bus } from './MyTypes.ts'

export type Vehicles= {
  Bus: Bus
  Car: Car
}

You can then use it like this :

const myCar: Vehicles["Car"] = { }
const myBike: Vehicles["Bike"] = { } // TS Error

I'd be still very interested in a fix, as I don't like this solution so much 🙏

[kkirby]

It seems to me that Parcel being a library bundler isn't a high priority feature. For libraries I've resorted to using tscp which is typescript with the ability to monkey patch functionality. Specifically, these two: @aliser/ts-transformer-append-js-extension and typescript-transform-paths. That way the output had the correct import paths relative to the output project.