Suggestion: a new rule NoEmptyLinesOpeningClosingBracesOnMethods - No empty lines on opening or closing braces in methods only

[Pispa339]

The existing rule NoEmptyLinesOpeningClosingBraces is somewhat too much of a catch-all rule. I'd like to request a more fine-grained rule where empty lines on opening or closing braces would be disallowed for methods, but allowed for type declarations.

For example the following would be disallowed within the rule

func hello() {

    // code starts here

whereas the following would be allowed

class SomeClass {

    // Code starts here

[ahoppen]

Synced to Apple’s issue tracker as rdar://136754857

[allevato]

These are the kinds of extremely fine-grained customizations that I'm really hesitant to add. NoEmptyLinesOpeningClosingBraces was added because it allows the formatter to be more opinionated across the board (which I think is a good goal). What would be the benefit of allowing the blank line for types but not functions?

[Pispa339]

This request stems mostly from this our team's preference and our desire to be able to configure the formatter to our liking. However, this also seems to be the formatting used in Apple's example projects like DiffableDataSourceSample for example.
I can definitely see why customization like this is not something one would consider worth pursuing given there's no real benefit beyond personal preference.

[0xLucasMarcal]

@allevato Any plans on supporting custom rules?

[allevato]

If by "custom rules" you mean some sort of plugin architecture where users would write something like a .dylib that contained additional rules that swift-format would recognize, it would be very nice to support something like that but we'd have to figure out the architectural details for it.

[0xLucasMarcal]

@allevato Yeah, that is exactly what I was imagining. I would love to contribute to the architectural design and the implementation of it. Let me know how I can best contribute to that with you :)