require.resolve() on Node 10 unexpectedly returns local JSON file

[Krinkle]

• Version: v10.15.2
• Platform: Linux
• Subsystem: modules

What steps will reproduce the bug?

mkdir /tmp/bug && cd /tmp/bug
echo '{"boo":1}' > qunit.json
npm install --save-dev qunit
node
> require.resolve( "qunit", { paths: [ process.cwd() ] } )

What is the expected behavior?

To return /tmp/bug/node_modules/qunit/qunit/qunit.js.

What do you see instead?

It returns /tmp/bug/qunit.json.

Additional information

This works as expected on Node.js v14.5.0, but it is broken on Node v10 LTS. As such, the QUnit CLI is broken for users that have a qunit.json file in their repository. The CLI is unable to startup due to local module resolution leading QUnit to import the JSON file, instead of the qunit npm module.

The code in question comes from qunit:/src/cli/require-qunit.js, which is meant to return what require('qunit') would return if run from the user's project.

As such, results that point to local files that would normally need to be prefixed ./ are not expected to be returned, similar to how require('qunit') in that directory, could not return the result of require('./qunit').

In the case of wikimedia/eslint-config this is not easily worked around, because the qunit.json in question is part of this module's public interface, exposed to npm users and to ESLint via eslintrc files, e.g. "extends": "eslint-config-wikimedia/qunit".

[Krinkle]

I looked through the change logs, but was not able to find which commit fixed this. I did find #18408, which might be related?

I'm hoping such bug fix could perhaps be backported still to Node.js 10. But, I can also see how one might consider that as semver-major. I'd understand declining this.

If declining, I do hope someone could let me know if there is a way this could be worked around by QUnit in the interim (until Node 10 reaches end-of-life).

[aduh95]

Out of curiosity, what is the behaviour for require.resolve("qunit/")? My guess is that would not catch qunit.json but rather the node_modules/qunit folder – unless there is a ./qunit/index.js file or something like this maybe.

[Krinkle]

@aduh95 That's right:

> process.versions.node
10.15.2
> require.resolve( "qunit", { paths: [ process.cwd() ] } )
'/eslint-config-wikimedia/qunit.json'
> require.resolve( "qunit/", { paths: [ process.cwd() ] } )
'/eslint-config-wikimedia/node_modules/qunit/qunit/qunit.js'

I also found another way, which makes it look at node_modules first:

> require.resolve( "qunit", { paths: [ process.cwd() + '/node_modules', process.cwd() ] } )
'/eslint-config-wikimedia/node_modules/qunit/qunit/qunit.js'

To my surprise, this works even when I misspell node_modules:

> require.resolve( "qunit", { paths: [ process.cwd() + '/zzz_not_here/' ] } )
'/eslint-config-wikimedia/node_modules/qunit/qunit/qunit.js'

Anyway, I think I'll go with adding node_modules for now, which seems least likely to change over time and/or regress other things I haven't thought of.

[targos]

Closing as v10.x reached end of life.