Stop using ESLint 5's ConfigFile.load, which is gone in ESLint 6.

[chrisbobbe]

prettier-eslint-cli can't currently use ESLint 6, and it would be great to fix that (see #304).

Ever since #91 was merged, pretter-eslint-cli has been using a util function ConfigFile.load that doesn't exist in ESLint 6; it was removed in eslint/eslint#11546 (merged in eslint/eslint@6ae21a4; released in v6.0.0-alpha.1).

To see the problem in action, get prettier-eslint-cli to use ESLint 6 (e.g., 6.8.0). One way to do this is to put lines like the following in the package.json of a project that uses prettier-eslint-cli:

+  "resolutions": {
+    "prettier-eslint-cli/eslint": "^6.8.0",
+    "prettier-eslint-cli/prettier-eslint": "^11.0.0"
+  }

Run yarn/npm install, then run the CLI, and see error output containing this:

Error: Cannot find module 'eslint/lib/config/config-file'

If it's important that we keep invoking ESLint's code for loading an ESLint config, it would be great to try to use something that's unambiguously part of ESLint's public API.

If it's not important, it might be good to stop doing so. In particular, I think the current behavior doesn't align with this bit of basic summary in the README for what prettier-eslint-cli does:

prettier-eslint-cli forwards on the filePath and other relevant options to prettier-eslint which identifies the applicable ESLint config for each file and uses that to determine the options for prettier and eslint --fix.

[github-actions]

Stale issue

[chrisbobbe]

Go away stale-bot, there’s no sign this issue has been fixed. 🙂

[chrisbobbe]

(I believe the issue still hasn't been fixed.)

[aronwoost]

It is not. 😕

[chrisbobbe]

Fixed in #431! 🎉