$ cat 2
has arg => qw(is rw isa ArrayRef), arg => qw(is rw isa ArrayRef), default => sub { [] };


$ perltidy < 2
has
  arg     => qw(is rw isa ArrayRef),
  arg     => qw(is rw isa ArrayRef),
  default => sub { [] };


$ perltidy -boc < 2
has arg => qw(is rw isa ArrayRef), arg => qw(is rw isa ArrayRef),
  default => sub { [] };