Plugins that are a dependency to a config package that aren't hoisted can't be loaded

[freaktechnik]

Tell us about your environment

Environment Info:

Node version: v13.11.0
npm version: v6.14.5
Local ESLint version: v7.4.0 (Currently used)
Global ESLint version: Not found

What parser (default, Babel-ESLint, etc.) are you using? I think default, but not relevant.

Please show your full configuration:

https://github.com/freaktechnik/transifex-loader/blob/master/src/.eslintrc.json

What did you do? Please include the actual source code causing the issue, as well as the command that you used to run ESLint.

Run eslint (npx eslint or npm run lint:js in that project).

What did you expect to happen?

Eslint to happily lint the project.

What actually happened? Please include the actual, raw output from ESLint.

eslint:config-array-factory Loaded: @freaktechnik/eslint-config-webpack@7.2.0 (/home/martin/dev/transifex-loader/node_modules/@freaktechnik/eslint-config-webpack/index.js) +1ms
  eslint:config-array-factory Loading JS config file: /home/martin/dev/transifex-loader/node_modules/@freaktechnik/eslint-config-webpack/index.js +0ms
  eslint:config-array-factory Loading {extends:"plugin:import/errors"} relative to /home/martin/dev/transifex-loader/node_modules/@freaktechnik/eslint-config-webpack/index.js +0ms
  eslint:config-array-factory Loading plugin "import" from /home/martin/dev/transifex-loader/node_modules/@freaktechnik/eslint-config-webpack/index.js +0ms
  eslint:config-array-factory Failed to load plugin 'import' declared in 'src/.eslintrc.json » @freaktechnik/eslint-config-webpack'. +1ms

Oops! Something went wrong! :(

ESLint: 7.4.0

ESLint couldn't find the plugin "eslint-plugin-import".

(The package "eslint-plugin-import" was not found when loaded as a Node module from the directory "/home/martin/dev/transifex-loader".)

It's likely that the plugin isn't installed correctly. Try reinstalling by running the following:

    npm install eslint-plugin-import@latest --save-dev

The plugin "eslint-plugin-import" was referenced from the config file in "src/.eslintrc.json » @freaktechnik/eslint-config-webpack".

Having plugins as dependencies of configs is working fine - in fact eslint happily loads a bunch of them before this. However, those plugins were all hoisted, this plugin is not. It is in /home/martin/dev/transifex-loader/node_modules/@freaktechnik/eslint-config-webpack/node_modules/eslint-plugin-import.

In order for the non-hoisted plugin to work

eslint/lib/cli-engine/config-array-factory.js

Lines 864 to 868 in ada2c89

	return this._loadConfigData({
	...ctx,
	filePath,
	name: `${ctx.name} » ${request}`
	});

would have to set pluginBasePath to the dirname of the config. I've verified that that makes everything work as expected. However that might break configs that expect their extends/plugins to be peer dependencies, I guess?

Are you willing to submit a pull request to fix this bug?

Sure, if this behavior is deemed incorrect (which I hope it is, since it makes eslint configs much more useful and not accidentally broken in a weird edge case). However I would need guidance toward how to/what to test.

[mdjermanovic]

Hi @freaktechnik, thanks for the issue.

I think this is a duplicate of #3458.

In short, having plugin as a dependency of a shareable config might work well in some cases, but it isn't actually supported. End users should install the plugin as a dev dependency. An alternative at the moment is to create a plugin instead of the shareable config, as described in #3458 (comment).

This will be changed in some of the future versions, per eslint/rfcs#9. With the new configuration file format, shareable configs will be able to specify plugins as direct dependencies.

[mdjermanovic]

I'm closing this since it isn't a bug with the actual configuration system. Per our documentation about shareable configs, end-users of a shareable config are required to specifiy all plugins as dev-dependecies:

If your shareable config depends on a plugin, you should also specify it as a peerDependency (plugins will be loaded relative to the end user's project, so the end user is required to install the plugins they need).

We are working on a new configuration file format that will support plugins as dependencies in shareable configs.

You can follow the implementation progress here: #13481