respect signature declaration style.

[aaronmallen]

Currently rbs inline will generate signatures that do not respect the RBS/Lint/AmbiguousOperatorPrecedence cop from rubocop-on-rbs.

Given the following declaration:

class MyClass
  # @rbs!
  #   interface _MyInterface
  #     def some_method: (untyped) -> bool
  #   end
  # 
  #   type some_type = Class | Module | Proc | (_MyInterface & Object)
end

RBS inline will generate the following signature:

class MyClass
  interface _MyInterface
    def some_method: (untyped) -> bool
  end

  type some_type = Class | Module | Proc | _MyInterface & Object # notice the lack of parentheses
end

Which violates the RBS/Lint/AmbiguousOperatorPrecedence cop. I am not suggesting RBS inline should directly support or even acknowledge the existence of the rubocop-on-rbs gem, however it would be pretty nice if it kept the signature how I wrote it so that I don't have to correct the cop violation everytime I regenerate signatures.

[ParadoxV5]

– and I thought @rbs! copy-pastes its contents verbatim.

[tk0miya]

Internally, RBS::Inline goes re-formatting RBS using RBS::Writer before generating a RBS file.
The RBS declarations are copy-pasted once to the buffer, but reformatted before generating.

For example, this code will be converted to the aligned RBS:

class Hello
  # @rbs!
  #   def hello
  #   : (
  #     name: String
  #     )
  #   -> (((Integer)))
end

class Hello
  def hello: (name: String) -> Integer
end

It seems the writer dropped the parens on reformatting. I'll take a look the module later.

[tk0miya]

FYI: I found RBS::Types::Union#to_s drops the parens.

irb(main):001> require 'rbs'
=> true
irb(main):002> RBS::Parser.parse_method_type("() -> (String | Integer & MyMod)").to_s
=> "() -> (String | Integer & MyMod)"
irb(main):003> RBS::Parser.parse_method_type("() -> (String | (Integer & MyMod))").to_s
=> "() -> (String | Integer & MyMod)"
irb(main):004> RBS::Parser.parse_type("(String | (Integer & MyMod))").to_s
=> "String | Integer & MyMod"

[tk0miya]

Now I posted ruby/rbs#2231. I hope it will be merged soon.