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Fix worker_threads module missing

Node

fabiorosado

How to fix the error "Cannot find module 'worker_threads'"

Table of contents
  1. How to fix the error "Cannot find module 'worker_threads'"
  2. The Problem
  3. The solution

At Coiled we use a few hooks that run with pre-commit. This means that before git commits your changes, these hooks will be run and report any failures. Using pre-commit is a great way to spot issues (like linting) before you do At Coiled we use a few hooks that run with pre-commit. This means that before git commits your changes, these hooks will be run and report any failures. Using pre-commit is a great way to spot issues (like linting) before you do your commits.

Everything went fine when I set up my dev environment, the command pre-commit install throw no errors when I ran it. But on my first commit, I got an error with pyright that apparently couldn’t find the worker_threads module.

The Problem

Pyright it’s a type checker for Python created by Microsoft. This was the first time I was using pyright so I have never encountered the error.

pyright..................................................................Failed
- hook id: pyright
- exit code: 1

internal/modules/cjs/loader.js:638
    throw err;
    ^

Error: Cannot find module 'worker_threads'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:636:15)
    at Function.Module._load (internal/modules/cjs/loader.js:562:25)
    at Module.require (internal/modules/cjs/loader.js:692:17)
    at require (internal/modules/cjs/helpers.js:25:18)
    at Object.5013 (/home/fabiorosado/.cache/pre-commit/repov31novgl/node_env-system/lib/node_modules/pyright/dist/pyright.js:1:597)
    at s (/home/fabiorosado/.cache/pre-commit/repov31novgl/node_env-system/lib/node_modules/pyright/dist/pyright.js:1:723)
    at Object.4221 (/home/fabiorosado/.cache/pre-commit/repov31novgl/node_env-system/lib/node_modules/pyright/dist/pyright-internal.js:1:204756)
    at s (/home/fabiorosado/.cache/pre-commit/repov31novgl/node_env-system/lib/node_modules/pyright/dist/pyright.js:1:723)
    at Object.8408 (/home/fabiorosado/.cache/pre-commit/repov31novgl/node_env-system/lib/node_modules/pyright/dist/pyright-internal.js:1:158250)
    at s (/home/fabiorosado/.cache/pre-commit/repov31novgl/node_env-system/lib/node_modules/pyright/dist/pyright.js:1:723)

tslint...............................................(no files to check)Skipped
tsc..................................................(no files to check)Skipped

This error made me unable to use pre-commit, which is a bummer because I kept forgetting to run black to automatically check and lint my code.

After exploring online, it seems that it might be a node issue, I’ve tried using Node Version Manager to update node to the latest version (15.3.0), but that didn’t work. So, I tried to install the latest node version manually, but that didn’t work as well.

The solution

After going through a few StackOverflow questions and Github issues, I came across this GitHub issue created on the electron repository - Unable to use NodeJs worker-threads module.

Running this command will be enough to fix the issue.

export NODE\_OPTIONS=--experimental-worker

Now I can run git commit, and my pre-commit will run without throwing any errors.