class RuboCop::Cop::RSpec::ExampleWording

def text(node)

that is the case for \-separated multiline strings with interpolation.
Recursive processing is required to process nested dstr nodes 
def text(node)
  case node.type
  when :dstr
    node.node_parts.map { |child_node| text(child_node) }.join
  when :str
    node.value
  else
    node.source
  end
end