default export doesn't work. "TypeError: xxx is not a function"

[colecrouter]

First off, thank you for making this!

I noticed in the installation section, your vite.config.js reads:

import comlink from 'vite-plugin-comlink'

In practice, I'm only able to get it to work with:

import { comlink } from 'vite-plugin-comlink'

Is this the intended behaviour?

[mathe42]

Yes your right will fix the code

[mathe42]

Released a fix as 3.0.1. Thanks for the report!

[ivancuric]

Still doesn't work. If importing the default export, I get the following error:

TypeError: comlink is not a function

[mathe42]

Are you sure you are on the latest version?

[ivancuric]

"vite-plugin-comlink": "^3.0.2"

[mathe42]

It works properly see https://github.com/mathe42/comlink-test please change to "3.0.2" and not "^3.0.2".

I need a full reproduction to fix that.

[ivancuric]

Here's my repro:
https://github.com/ivancuric/vite-workers/tree/repro-broken-comlink

failed to load config from /Users/ivan/Dev/vite-workers/vite.config.js
error when starting dev server:
TypeError: comlink is not a function
    at file:///Users/ivan/Dev/vite-workers/vite.config.js?t=1653404879713:4:13
    at ModuleJob.run (node:internal/modules/esm/module_job:198:25)
    at async Promise.all (index 0)
    at async ESMLoader.import (node:internal/modules/esm/loader:385:24)
    at async importModuleDynamicallyWrapper (node:internal/vm/module:437:15)
    at async loadConfigFromFile (/Users/ivan/Dev/vite-workers/node_modules/vite/dist/node/chunks/dep-59dc6e00.js:61843:31)
    at async resolveConfig (/Users/ivan/Dev/vite-workers/node_modules/vite/dist/node/chunks/dep-59dc6e00.js:61376:28)
    at async createServer (/Users/ivan/Dev/vite-workers/node_modules/vite/dist/node/chunks/dep-59dc6e00.js:59783:20)
    at async CAC.<anonymous> (/Users/ivan/Dev/vite-workers/node_modules/vite/dist/node/cli.js:688:24)
    ```

[mathe42]

I could reproduce that but have no idea why. I will investigate please use import {comlink} from 'vite-plugin-comlink' for now...

[mathe42]

I have no idea why it works with my project and not yours. I published a new version 3.0.3 that didn't fix it. I will keep looking into it but not today.

[mathe42]

I have NO idea why it worked for me... I will change the readme for now until I find a solution...

[colecrouter]

Normally, you just have to change

export function

To

export default function

Right? I can't explain the local reproduction issue, though.

[ivancuric]

It's the "type": "module" in the project's package.json which breaks it. This instructs the project to use esm module resolution with node 16+

Seems that something is broken with the .mjs module, but this looks fine.

var src_default = comlink;
export {
  comlink,
  src_default as default
};

[mathe42]

It uses the normal .js file in both cases. but I think you are right that this is the problem I'm not sure why node uses the default import the same as import * as comlink from 'vite-plugin-comlink'

[ivancuric]

It does, but it should be using the .mjs I think.

I can't get it to load the mjs file. I've tried adding "type": "module" to your package.json, but then everything falls apart.

[mathe42]

note that this might be a combination with vite problem as at vite startup the config file is compiled to JS (and I think the complete config is bundled to a single file internaly.) The output of that is interpreted as a commonjs (or with type=module a esm)-File.

[mathe42]

What is the reason you want to set type: module in a vite project. You could just change all .js extensions to .mjs where you have some code for node... the type field doesn't matter for vite-plugins and files vite processes.

[ivancuric]

I have it as it's kinda the new standard, not much else. I also had some errors with https://github.com/liuweiGL/vite-plugin-mkcert which I fixed by calling mkcert.default() instead of mkcert()

Could this be related to vitejs/vite#6623?

I also noticed that when compiling in lib mode in Vite, they recommend using the following package.json:

{
  "name": "my-lib",
  "files": ["dist"],
  "main": "./dist/my-lib.umd.js",
  "module": "./dist/my-lib.es.js",
  "exports": {
    ".": {
      "import": "./dist/my-lib.es.js",
      "require": "./dist/my-lib.umd.js"
    }
  }
}

Compared to yours it's missing the exports field.

[mathe42]

Might be. exports field doesn't change anything. Reproduction is still broken. I think the best solution is to avoid the default import. vite 3 will have some changes with esm files etc. so I would not touch it for now and wait for the 3.0 release.

[mathe42]

I know that vite 3 is out but I'm currently quite busy (I'm in my last year of University) so at least in the next 4-5 Weeks don't expect a fix. I didn't even had a look at vite 3 yet. (so also vite-plugin-comlink version 4 is pushed back). On npmjs I can see that a lot of persons only use an old version:

So there is no harm in waiting for v4 as it will have a number of breaking changes.