class RuboCop::Cop::Style::SpaceBeforeBlockBraces

def space_detected(left_brace, space_plus_brace)
  space = range_between(space_plus_brace.begin_pos,
                        left_brace.begin_pos)
  add_offense(space, space, 'Space detected to the left of {.') do
    opposite_style_detected
  end
end