Default rules enabled / extends

I have not much knowledge of EsLint, but it is annoying to go through all rules and find out, which to use.

Could not you – just like plain EsLint – somehow also use a thing/things like "extends": "eslint:recommended", so one can get a set of rules that are almost always good for mocha tests?

I think there are many rules that should be enabled “by default”/“by extends”.

[Lakitna]

I would very much like a proper recommended ruleset. So let me kick off the discussion.

How about the following

// Will always result in a failed test, throw error to prevent this
'mocha/handle-done-callback': 'error',

// For low level tests it makes a lot of sense to enforce a single top level suite. For higher
// level tests you'll sometimes want more that one top level suite, but not often. Enforcing
// at 1 seems best for recommended
'mocha/max-top-level-suites': ['error', {limit: 1}],

// Exclusive tests (`.only`) in CI should be caught with `--forbid-only`. While working on
// tests a warning will suffice.
'mocha/no-exclusive-tests': 'warn',

// A test is always run in context, not adding a suite is a bad practice on the maintenance
// side of things.
'mocha/no-global-tests': 'error',

// Hooks (`.before` etc) are a very powerful part of Mocha and should not be disallowed.
// Disallowing this is very opinionated. 
'mocha/no-hooks': 'off',

// This can be a sign of bad test design. It can also be a valid separation of concerns imo.
// Am I opinionated?
'mocha/no-hooks-for-single-case': 'warn',

// You probably made a copypasta oopsy
'mocha/no-identical-title': 'error',

// `it(() => {})` should never be used because you loose `this`. A common trap that can be
// prevented with this rule
'mocha/no-mocha-arrows': 'error',

// Nested tests don't behave like you expect. You probably wanted to make a suite
'mocha/no-nested-tests': 'error',

// `it('is pending');`
// Not sure about this one. Might have to make this an error?
'mocha/no-pending-tests': 'warn',

// According to the docs, it causes a failure in Mocha. Prevent that with this rule
'mocha/no-return-and-callback': 'error',

// You should do this kind of thing in a hook.
'mocha/no-setup-in-describe': 'error',

// Generally confusing and unnecessary. The few times where you do want this you can
// skip the rule with an annotation. 
'mocha/no-sibling-hooks': 'error',

// Skipping tests can be a bad thing you should not forget about. I'm not sure about this
// one but I'd say you should catch this with `--forbid-pending` when you want to fail on
// this.
'mocha/no-skipped-tests': 'warn',

// Opinionated
'mocha/no-synchronous-tests': 'off',

// Hooks should always be part of a suite
'mocha/no-top-level-hooks': 'error',

// Opinionated
'mocha/prefer-arrow-callback': 'off',

// Opinionated and dependent on the way the project chooses to structure things
'mocha/valid-suite-description': 'off',

// Opinionated and dependent on the way the project chooses to structure things
'mocha/valid-test-description': 'off',

// Results in unexpected behaviour
'mocha/no-async-describe': 'error',

[lo1tuma]

That sounds reasonable.