Change 458479 had a related patch set uploaded (by D3r1ck01; owner: Alangi Derick):
[mediawiki/extensions/Wikibase@master] Add recent pattern for ESLinting to repo

https://gerrit.wikimedia.org/r/458479

Change 458474 had a related patch set uploaded (by D3r1ck01; owner: Alangi Derick):
[mediawiki/extensions/WikiEditor@master] Add recent pattern for ESLinting to repo

https://gerrit.wikimedia.org/r/458474

Change 458486 had a related patch set uploaded (by D3r1ck01; owner: Alangi Derick):
[mediawiki/extensions/UniversalLanguageSelector@master] Add recent pattern for ESLinting to repo

https://gerrit.wikimedia.org/r/458486

This is really ugly. I think we should do the reverse; linting file configuration should be as much as possible in Gruntfile.js, and linting rule configuration in specific files (.eslintrc.json, .stylelintrc.json, …).

Change 458486 merged by jenkins-bot:
[mediawiki/extensions/UniversalLanguageSelector@master] Add recent pattern for ESLinting to repo

https://gerrit.wikimedia.org/r/458486

@Jdforrester-WMF I don't think the file patterns belong in Gruntfile. It's non-standard from the tools perspective in that IDE plugins and the linter's cli tools do not support it. For phpunit we configure the files in a format phpunit understands, for phpcs we use phpcs.xml, for JSHint we used jshintignore. So it makes sense that for ESLint we also use a way that ESLint itself can configure so that if I run eslint . on the project it Just Works.

That leaves us with three options:

• Specify the patterns to package.json which eslint looks for, just like how it looks for eslintrc.
• Specify the patterns to a new file, .eslintignore, which eslint also looks for.
• Specify the patterns on the command line to eslint using --ignore-pattern, and call eslint from npm test script in package.json as eslint . && grunt test, and remove it from Gruntfile entirely.

So far, we've done the first option in a number of repositories. The other options I only discovered later. It seemed to me like a net improvement:

• No longer hardcoded in Gruntfile, meant it became known to ESLint by standard means for running eslint --fix . and other command line tools and IDE plugins.
• It made the traversal more efficient by happening inside ESLint lazily instead of ahead of time inside Grunt.
• It made it impossible to forget to include a new directory by being opt-out instead of opt-in. Although most repos now use **/*.js, during this conversion I also found a few that were opting-in instead of all-in and then exclude. By specifying the excludes separately one is nudged away from that anti-pattern.

Having said that, I'd also be fine with picking one of the other two options, or another method entirely that addresses the above.

I don't think hacking around poor support in IDEs is a good motive for this kind of change, but I grok the desire for eslint . to work for those people who have eslint installed globally (which is a versioning/rules compatibility risk, but that problem is on them). The least-terrible option would be an .eslintignore file, I think.

Change 458479 merged by jenkins-bot:
[mediawiki/extensions/Wikibase@master] Add recent pattern for ESLinting to repo

https://gerrit.wikimedia.org/r/458479

@Jdlrobson, @Krinkle, so based on discussions above, this will be the way forward? https://gerrit.wikimedia.org/r/c/mediawiki/extensions/MobileFrontend/+/457958

Change 458474 abandoned by D3r1ck01:
Add recent pattern for ESLinting to repo

Reason:
Thanks @JForrester. Abandoning as discussion is happening here: T204176.

https://gerrit.wikimedia.org/r/458474