@implements in blocks

[soutaro]

Some methods including #instance_eval change the value of self inside the given block. @type self annotation is for this case, but it doesn't work for method definitions. We typically see this when we use Struct class.

ReadMessageJob = _ = Struct.new(:source, :message) do
  # @implements ReadMessageJob

  def request?
    message[:method] && message[:id]
  end
end

The problem is

1. @implements annotations inside blocks are ignored.
2. @type self: T and @type module: T are not for method definitions.

So, I'd like to extend @implements annotations to be placed inside blocks.

[soutaro]

Doesn't work for:

class Methods
  Definition = _ = Struct.new(:name, :type, :originals, :overloads, :accessibilities, keyword_init: true) do
    # @implements Definition

    def self.empty(name:, type:)
      new(type: type, name: name, originals: [], overloads: [], accessibilities: [])
    end
  end
end

The new call in self.empty is resolved to Methods.new. 💣