Rule request: Comment lines in function bodies

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• Updated SwiftLint to the latest version
• I searched for existing GitHub issues

Rule Request

Description

The code, in my opinion, should not have in-line comments. If any kind of explanations is needed, it has to be put in the method or class documentation. Furthermore, if your code requires comments, then it might be necessary to refactor it, so that it would be self-explainatory.

What would trigger?

internal func exceedsLineCountExcludingCommentsAndWhitespace(_ start: Int, _ end: Int, _ limit: Int) -> (Bool, Int) {
        guard end - start > limit else {
            return (false, end - start)
        }
        // I will put this here instead of putting in the method doc, where it belongs.
        let count = end - start - numberOfCommentAndWhitespaceOnlyLines(startLine: start, endLine: end)
        return (count > limit, count)
    }

What would not trigger?

internal func exceedsLineCountExcludingCommentsAndWhitespace(_ start: Int, _ end: Int, _ limit: Int) -> (Bool, Int) {
        guard end - start > limit else {
            return (false, end - start)
        }
        let count = end - start - numberOfCommentAndWhitespaceOnlyLines(startLine: start, endLine: end)
        return (count > limit, count)
    }

Configurable?

The rule should not be configurable.

Opt-in or enabled?

This rule could be a personal preference or coding style from various individuals, so it could be kept as opt-in.

Start with the trigger and non-trigger examples in issue #2077 and review the requested opt-in, non-configurable behavior. Done means comments inside function bodies trigger the rule, while the shown comment-free function does not, with the rule available only as opt-in.