class RuboCop::Cop::Lint::EmptyInterpolation

“result is #{}”
@example
This cop checks for empty interpolation.

def on_dstr(node) 

def on_dstr(node)
  node.children.select { |n| n.type == :begin }.each do |begin_node|
    add_offense(begin_node, :expression) if begin_node.children.empty?
  end
end