Using YARD Annotations

Types are extracted from the YARD annotations

Consider the following method:

       # @return [String] 
      def black_box(param1, param2)
end

The only information about the method is the return type, specified in the YARD tag. This is enough for RubyMine to suggest proper code completion (Ctrl+SpaceCtrl+Space):

If the parameter type is declared in the documentation comment, then code completion inside the method body suggests only the relevant choices:

Intention actions suggest to create YARD tags, if missing.

If in the same code block, the @return or @param tags are missing, RubyMine provides intention actions (Alt+EnterAlt+Enter):

In-place rename refactoring

The rename refactoring involves the YARD tags:

Code inspections and quick fixes.

RubyMine validates the tags for duplicated or wrong parameter names:

Viewing YARD descriptions in the quick documentation pop-up.

RubyMine properly renders the YARD tags in the quick documentation pop-up window: