class RuboCop::Cop::Lint::EndInMethod

END { do_something }
# outside defs
# good
@example
end
at_exit { do_something }
def some_method
# good
@example
end
END { do_something }
def some_method
# bad
@example
This cop checks for END blocks in method definitions.

def on_postexe(node) 

def on_postexe(node)
  inside_of_method = node.each_ancestor(:def, :defs).count.nonzero?
  add_offense(node, :keyword) if inside_of_method
end