ErrorHighlight::Spotter#spot_defn

# File tmp/rubies/ruby-4.0.0/lib/error_highlight/base.rb, line 659
def spot_defn
  mid, = @node.children
  fetch_line(@node.first_lineno)
  if @snippet.match(/\Gdef\s+(#{ Regexp.quote(mid) }\b)/, @node.first_column)
    @beg_column = $~.begin(1)
    @end_column = $~.end(1)
  end
end