File Coverage

blib/lib/DateTimeX/Role/Immutable.pm

Criterion	Covered	Total	%
statement	29	29	100.0
branch			n/a
condition			n/a
subroutine	10	10	100.0
pod	0	1	0.0
total	39	40	97.5

package DateTimeX::Role::Immutable;

# ABSTRACT: A role that can be composed into a DateTime subclass to make it immutable

use strict;
use warnings;
use Carp;
use Role::Tiny;
use Sub::Install;
use DateTime;
use namespace::autoclean;

our $VERSION = '0.36';

my %mutators = (
    add_duration      => 'plus_duration',
    subtract_duration => 'minus_duration',
    add               => 'plus',
    subtract          => 'minus',
    truncate          => 'trunc',
    set               => 'with_component',
    set_year          => 'with_year',
    set_month         => 'with_month',
    set_day           => 'with_day',
    set_hour          => 'with_hour',
    set_minute        => 'with_minute',
    set_second        => 'with_second',
    set_nanosecond    => 'with_nanosecond',
);
## Consider: set_time_zone set_locale set_formatter

before keys %mutators => sub {
    my $orig = shift;
    my $self = shift;

    croak "Attempted to mutate a DateTime object";
};

while ( my ( $orig_method, $new_method ) = each %mutators ) {
    Sub::Install::install_sub( {
            code => sub {
                my $self = shift;
                my $new_dt = DateTime->from_object( object => $self );
                $new_dt->$orig_method(@_);
                return bless $new_dt, ref $self;
            },
            as => $new_method,
        } );
}

# Methods that return a duration, but mutate during processing
for my $method (
    qw(delta_md delta_days delta_ms subtract_datetime subtract_datetime_absolute)
  )
{
    Sub::Install::install_sub( {
            code => sub {
                my $dt1 = DateTime->from_object( object => shift );
                my $dt2 = DateTime->from_object( object => shift );
                return $dt1->$method( $dt2, @_ );
            },
            as => $method,
        } );
}

# Need to replace today, as the DateTime
sub today { shift->now(@_)->trunc( to => 'day' ) }

1;

__END__