[Bug?]: Process hangs with parallel-prettier

[AllanZhengYP]

Self-service

• I'd be willing to implement a fix

Describe the bug

We use the dependency @mixer/parallel-prettier to prettify our huge codebase in parallel. However, formatting process hangs if the dependency co-exists with some other dependencies(i.e. concurrently). I looked into the source code, it looks normal, other than it uses cluster module.

To reproduce

---

Playground

await packageJsonAndInstall({
    devDependencies: {
        "@mixer/parallel-prettier": "^2.0.1",
        "concurrently": "7.0.0" // <==== this is causing the process to hang. Removing this the app runs properly again.
    },
    scripts: {
        "format": "pprettier --write ./package.json"
    },
    packageManager: "yarn@3.2.0",
});


expect(await yarn('run', 'format')).toBeDefined();

Environment

System:
    OS: macOS 12.2.1
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 14.19.1 - /private/var/folders/28/yhtzwdv94rg8cf93ncdjc02h0000gr/T/xfs-2f0d5096/node
    Yarn: 3.2.0 - /private/var/folders/28/yhtzwdv94rg8cf93ncdjc02h0000gr/T/xfs-2f0d5096/yarn
    npm: 6.14.16 - ~/.nvm/versions/node/v14.19.1/bin/npm

Additional context

I did a search in our other dependencies, it seems like many other dependencies will cause the same issue like concurrently:

    "@commitlint/cli": "^11.0.0",
    "@typescript-eslint/eslint-plugin": "5.15.0",
    "@typescript-eslint/parser": "5.15.0"
    "concurrently": "7.0.0",
    "eslint": "8.11.0",
    "lerna": "3.22.1",
    "lint-staged": "^10.0.1",
    "mocha": "^8.0.1",
    "ts-jest": "27.1.4"
    "strip-comments": "2.0.1"
    "esprint": "3.3.0"
    "jest": "27.4.5",
    "karma": "^5.1.0",
    "karma-typescript": "5.5.3"

I don't think they share a lot commonalities.

[merceyz]

I'm guessing this is the same issue as #4157, can you test with Node.js v16.14 or v17.4?

[AllanZhengYP]

@merceyz Thank you for the response. I tested on v16.14 but still got no luck:

  System:
    OS: macOS 12.2.1
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 16.14.2 - /private/var/folders/28/yhtzwdv94rg8cf93ncdjc02h0000gr/T/xfs-79ab10bc/node
    Yarn: 3.2.0 - /private/var/folders/28/yhtzwdv94rg8cf93ncdjc02h0000gr/T/xfs-79ab10bc/yarn
    npm: 8.5.0 - ~/.nvm/versions/node/v16.14.2/bin/npm

[AllanZhengYP]

@merceyz The issue still exists, can you take another look?

[RDIL]

I attempted to reproduce the issue, but didn't have any luck. Are you able to provide a repository that allows for a minimal reproduction of the behavior?

[merceyz]

I can reproduce with the following commands

docker run --rm -it node:16.15.0 bash
mkdir foo
cd foo
corepack enable
corepack prepare yarn@3.2.1 --activate
yarn init
yarn add @mixer/parallel-prettier@2.0.1 concurrently@7.0.0
yarn pprettier --write ./package.json

[RDIL]

Interesting discovery... after running yarn config set pnpEnableEsmLoader false, it starts working. I wonder if this is some type of dynamic import type issue, or the issue Node.js had for a while with child_processes not being ready when loaded under ESM.