Cannot find module 'internal/bootstrap/loaders'

[dcastil]

• Version: v12.17.0 (but same issue with v10.20.1, v10.13.0, v8.17.0 and v6.17.1)
• Platform: Darwin dany 19.5.0 Darwin Kernel Version 19.5.0: Thu Apr 30 18:25:59 PDT 2020; root:xnu-6153.121.1~7/RELEASE_X86_64 x86_64
• Subsystem: not sure

What steps will reproduce the bug?

Install NodeJS (I use n, but I also reinstalled with Node installer from website), create file test.js

require('internal/bootstrap/loaders')

and run

node test

How often does it reproduce? Is there a required condition?

I'm sure that it's not generally reproducible, but I can't figure out why this issue is occurring. I ran into this issue when I tried to use esm which internally uses require('internal/bootstrap/loaders').

What is the expected behavior?

Module can be loaded without throwing an error.

What do you see instead?

internal/modules/cjs/loader.js:969
  throw err;
  ^

Error: Cannot find module 'internal/bootstrap/loaders'
Require stack:
- /Users/dany/code/theme-ui-vscode/test.js
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:966:15)
    at Function.Module._load (internal/modules/cjs/loader.js:842:27)
    at Module.require (internal/modules/cjs/loader.js:1026:19)
    at require (internal/modules/cjs/helpers.js:72:18)
    at Object.<anonymous> (/Users/dany/code/theme-ui-vscode/test.js:1:1)
    at Module._compile (internal/modules/cjs/loader.js:1138:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1158:10)
    at Module.load (internal/modules/cjs/loader.js:986:32)
    at Function.Module._load (internal/modules/cjs/loader.js:879:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [ '/Users/dany/code/theme-ui-vscode/test.js' ]
}

Additional information

I'm using a Mac with two users which are sharing node and npm (I'm using them for work / private), maybe that plays a role here? But the error happens on both users. I tried the proposed solutions of #9355 and #9377 but nothing worked for me unfortunately.

[dcastil]

Actually a friend of mine just ran the command

echo "require('internal/bootstrap/loaders')" | node

on her machine and it threw the exact same error. 🤔

[richardlau]

This is intentional. Internal modules are not meant to be require-able for user code. There is a command line flag to expose them to our own tests but we don't publicize that flag to minimize misuse.

If you're having issues with the esm module you should report that on their issues tracker.

[dcastil]

Ah I just discovered that the require('internal/bootstrap/loaders') is in a try {} block. My bundler hoisted that require() call out of the try {} block which caused the issue.

Thanks for clarifying!