RubyMine - automatically detect .each, .map, and other iterator types

Question

In RubyMine I can write

# @param [Array<MyClass>] things
def foo(things)
end

and RubyMine will autocomplete MyClass methods for things.first.*. However, when I loop through each, like:

# @param [Array<MyClass>] things
def foo(things)
    things.each { |t| t.* }
end

RubyMine loses its type inference. I know I can add comments to specify block parameter types, but looping through an object of some type should only yield parameters of that type anyway.

Is there any way I can write a custom rule for RubyMine so that .each, .map, and other iterators are presumed to have the type of the variable its called upon?

Answer 1

From my research, it looks like you may be able to annotate like so:

# @param [Array<MyClass>] things
def foo(things)
  things.each {
    # @type [MyClass] t 
    |t|
    t.*
  }
end

Source: https://youtrack.jetbrains.com/issue/RUBY-9142#comment=27-787975