cjs context globals are available unexpected in ESM when using `node --eval 'import("pkg")'`

[JounQin]

Version

v22.13.1

Platform

Linux mightyiam-eslintconfigl-deiiy42chvs 6.1.91-060191-generic #202407021948 SMP PREEMPT_DYNAMIC Tue Jul  2 20:28:47 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

No response

What steps will reproduce the bug?

un-ts/eslint-plugin-import-x#296

npm install -D eslint-plugin-import-x@4.10.3

node --eval 'import("eslint-plugin-import-x")'

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

consistently

What is the expected behavior? Why is that the expected behavior?

No error

What do you see instead?

node:internal/modules/cjs/loader:1244
  const err = new Error(message);
              ^

Error: Cannot find module '../package.json'
Require stack:
- /tmp/L5XoA9/[eval]
    at Function._resolveFilename (node:internal/modules/cjs/loader:1244:15)
    at Function._load (node:internal/modules/cjs/loader:1070:27)
    at TracingChannel.traceSync (node:diagnostics_channel:322:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:217:24)
    at Module.require (node:internal/modules/cjs/loader:1335:12)
    at require (node:internal/modules/helpers:136:16)
    at file:///tmp/L5XoA9/node_modules/eslint-plugin-import-x/lib/meta.js:5:34
    at ModuleJob.run (node:internal/modules/esm/module_job:271:25)
    at async onImport.tracePromise.__proto__ (node:internal/modules/esm/loader:547:26)
    at async importModuleDynamicallyWrapper (node:internal/vm/module:436:15) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [ '/tmp/L5XoA9/[eval]' ]
}

Node.js v22.13.1

Additional information

eslint-plugin-import-x is a dual package

[JounQin]

Running with Worker eval also has this issue, the difference is that __filename been [eval] and [worker eval].

[aduh95]

Can you send a repro that doesn't involve any npm command / downloading code from the internet?

[JounQin]

@aduh95 Here we go: https://github.com/JounQin/test/tree/repro/node_esm

node index.js

node index.js                                                   
file:///Users/JounQin/Workspaces/GitHub/test/index.js:1
console.log(__filename)
            ^

ReferenceError: __filename is not defined in ES module scope
This file is being treated as an ES module because it has a '.js' file extension and '/Users/JounQin/Workspaces/GitHub/test/package.json' contains "type": "module". To treat it as a CommonJS script, rename it to use the '.cjs' file extension.
    at file:///Users/JounQin/Workspaces/GitHub/test/index.js:1:13
    at ModuleJob.run (node:internal/modules/esm/module_job:263:25)
    at async ModuleLoader.import (node:internal/modules/esm/loader:540:24)
    at async asyncRunEntryPointWithESMLoader (node:internal/modules/run_main:117:5)

node -e 'import("./index.js")

[eval]

[aduh95]

Instead of a full fledge repo, I find it easier to send a script that create the required parts instead of letting the maintainers figure out for themselves what are the important parts.

mkdir repro
cd repro
echo 'console.log(__filename)' > index.js
echo '{ "type": "module" }' > package.json
! node index.js
node -p 'import("./index.js")'
cd ..
rm -r repro

It is indeed the case that __filename is global in this context (and always has been AFAIR), and the documentation is not clear on that point. If we were to change the behavior, I think we have three options, ordered from most breaking to least breaking:

• not expose any __filename
• use a similar trick as we're doing for crypto since lib: enable global WebCrypto by default #42083
• keep the current behavior, only update the docs

[JounQin]

It is indeed the case that __filename is global in this context (and always has been AFAIR)

But it's unavailable with node index.js, what means the behavior is inconsistent.

[aduh95]

It's the same for all other --eval only globals, such as assert, fs, module, exports, etc.