File Coverage

blib/lib/Promises6/Deferred.pm

Criterion	Covered	Total	%
statement	71	71	100.0
branch	29	48	60.4
condition			n/a
subroutine	11	11	100.0
pod	9	9	100.0
total	120	139	86.3

package Promises6::Deferred;
use Evo -class, -modern;
use Promises6::Util ':all';

# [state, val]
has [qw(result builder)];
has subscribers => sub { [] };
has 'is_adaptor';

# public methods -----------
sub promise($self) { $self->builder->promise(deferred => $self) }

sub resolve($self, $val) {
  return if $self->is_adaptor;
  $self->builder->resolver->resolve($self, $val);
  $self;
}

# don't try to resolve
sub reject($self, $reason) {
  return if $self->is_adaptor;
  $self->change_state(REJECTED, $reason);
  $self;
}

sub notify($self, $val) {
  $self->state eq PENDING && $self->broadcast(PROGRESS, $val);
}

# implementation methods -----------
sub state($self) { $self->result or return PENDING; $self->result->[0] }

sub change_state($self, $state, $val) {
  return unless $self->state == PENDING;
  $self->result([$state, $val])->broadcast($state, $val);

  # prevent future errors, don't do delete $self->{subscribers}
  $self->{subscribers} = 0;
  $self;
}

sub broadcast($self, $state, $val) {
  $self->send_msg($_, $state, $val) for $self->subscribers->@*;
}


# you can use loop here
sub send_msg($self, $listener, $state, $val) {
  $listener->get_msg($state, $val);
}

sub subscribe($self, $listener) {
  return push $self->subscribers->@*, $listener if $self->state eq PENDING;

  # already resolved
  $self->send_msg($listener, $self->result->@*);
}

1;

__END__