eslint: dependency wrongly mark as unused

This is likely introduced by https://github.com/depcheck/depcheck/issues/476 and https://github.com/depcheck/depcheck/pull/477

Back in this previous issue, the contributor (@sveyret) wrote:

when analyzing eslint configuration dependencies, it does not look at this dependencies’ dependencies.

It should not, seems to me this is defeating the general behavior of depcheck. Any dependency that is explicitly used or imported in the project should be declared in package.json, even if it’s already made available by another dependency. I just spent some time troubleshooting this in a project.

I had the following eslint config:

extends:
  - standard-jsx
  - standard-react

And the following lines in package.json:

    "eslint-config-standard": "^12.0.0",
    "eslint-config-standard-jsx": "^8.1.0",
    "eslint-config-standard-react": "^9.0.0",

And depcheck was outputing:

Unused devDependencies
* eslint-config-standard-jsx

Because eslint-config-standard-jsx is a dependency of eslint-config-standard-react, it’s marked as ‘unused’. I don’t think that’s right.

[sveyret]

Hi @znarf, I made a pull request (#506) which should correct your issue. Would you please have time to check it?

[sveyret]

For information, I’ll take the point tomorrow if I can find time.