package Moose::Meta::Role::Application::RoleSummation;
use strict;
use warnings;
use metaclass;
use Carp 'confess';
use Scalar::Util 'blessed';
use Data::Dumper;
use Moose::Meta::Role::Composite;
our $VERSION = '0.01';
our $AUTHORITY = 'cpan:STEVAN';
use base 'Moose::Meta::Role::Application';
__PACKAGE__->meta->add_attribute('role_params' => (
reader => 'role_params',
default => sub { {} }
));
sub get_exclusions_for_role {
my ($self, $role) = @_;
$role = $role->name if blessed $role;
if ($self->role_params->{$role} && defined $self->role_params->{$role}->{excludes}) {
if (ref $self->role_params->{$role}->{excludes} eq 'ARRAY') {
return $self->role_params->{$role}->{excludes};
}
return [ $self->role_params->{$role}->{excludes} ];
}
return [];
}
sub get_method_aliases_for_role {
my ($self, $role) = @_;
$role = $role->name if blessed $role;
if ($self->role_params->{$role} && defined $self->role_params->{$role}->{alias}) {
return $self->role_params->{$role}->{alias};
}
return {};
}
sub is_method_excluded {
my ($self, $role, $method_name) = @_;
foreach ($self->get_exclusions_for_role($role->name)) {
return 1 if $_ eq $method_name;
}
return 0;
}
sub is_method_aliased {
my ($self, $role, $method_name) = @_;
exists $self->get_method_aliases_for_role($role->name)->{$method_name} ? 1 : 0
}
sub is_aliased_method {
my ($self, $role, $method_name) = @_;
my %aliased_names = reverse %{$self->get_method_aliases_for_role($role->name)};
exists $aliased_names{$method_name} ? 1 : 0;
}
# stolen from List::MoreUtils ...
my $uniq = sub { my %h; map { $h{$_}++ == 0 ? $_ : () } @_ };
sub check_role_exclusions {
my ($self, $c) = @_;
my @all_excluded_roles = $uniq->(map {
$_->get_excluded_roles_list
} @{$c->get_roles});
foreach my $role (@{$c->get_roles}) {
foreach my $excluded (@all_excluded_roles) {
confess "Conflict detected: " . $role->name . " excludes role '" . $excluded . "'"
if $role->does_role($excluded);
}
}
$c->add_excluded_roles(@all_excluded_roles);
}
sub check_required_methods {
my ($self, $c) = @_;
my %all_required_methods = map { $_ => undef } $uniq->(map {
$_->get_required_method_list
} @{$c->get_roles});
foreach my $role (@{$c->get_roles}) {
foreach my $required (keys %all_required_methods) {
delete $all_required_methods{$required}
if $role->has_method($required)
|| $self->is_aliased_method($role, $required);
}
}
$c->add_required_methods(keys %all_required_methods);
}
sub check_required_attributes {
}
sub apply_attributes {
my ($self, $c) = @_;
my @all_attributes = map {
my $role = $_;
map {
+{
name => $_,
attr => $role->get_attribute($_),
}
} $role->get_attribute_list
} @{$c->get_roles};
my %seen;
foreach my $attr (@all_attributes) {
if (exists $seen{$attr->{name}}) {
confess "We have encountered an attribute conflict with '" . $attr->{name} . "'"
. "during composition. This is fatal error and cannot be disambiguated."
if $seen{$attr->{name}} != $attr->{attr};
}
$seen{$attr->{name}} = $attr->{attr};
}
foreach my $attr (@all_attributes) {
$c->add_attribute($attr->{name}, $attr->{attr});
}
}
sub apply_methods {
my ($self, $c) = @_;
my @all_methods = map {
my $role = $_;
my $aliases = $self->get_method_aliases_for_role($role);
my %excludes = map { $_ => undef } @{ $self->get_exclusions_for_role($role) };
(
(map {
exists $excludes{$_} ? () :
+{
role => $role,
name => $_,
method => $role->get_method($_),
}
} $role->get_method_list),
(map {
+{
role => $role,
name => $aliases->{$_},
method => $role->get_method($_),
}
} keys %$aliases)
);
} @{$c->get_roles};
my (%seen, %method_map);
foreach my $method (@all_methods) {
if (exists $seen{$method->{name}}) {
if ($seen{$method->{name}}->body != $method->{method}->body) {
$c->add_required_methods($method->{name});
delete $method_map{$method->{name}};
next;
}
}
$seen{$method->{name}} = $method->{method};
$method_map{$method->{name}} = $method->{method};
}
$c->alias_method($_ => $method_map{$_}) for keys %method_map;
}
sub apply_override_method_modifiers {
my ($self, $c) = @_;
my @all_overrides = map {
my $role = $_;
map {
+{
name => $_,
method => $role->get_override_method_modifier($_),
}
} $role->get_method_modifier_list('override');
} @{$c->get_roles};
my %seen;
foreach my $override (@all_overrides) {
confess "Role '" . $c->name . "' has encountered an 'override' method conflict " .
"during composition (A local method of the same name as been found). This " .
"is fatal error."
if $c->has_method($override->{name});
if (exists $seen{$override->{name}}) {
confess "We have encountered an 'override' method conflict during " .
"composition (Two 'override' methods of the same name encountered). " .
"This is fatal error."
if $seen{$override->{name}} != $override->{method};
}
$seen{$override->{name}} = $override->{method};
}
$c->add_override_method_modifier(
$_->{name}, $_->{method}
) for @all_overrides;
}
sub apply_method_modifiers {
my ($self, $modifier_type, $c) = @_;
my $add = "add_${modifier_type}_method_modifier";
my $get = "get_${modifier_type}_method_modifiers";
foreach my $role (@{$c->get_roles}) {
foreach my $method_name ($role->get_method_modifier_list($modifier_type)) {
$c->$add(
$method_name,
$_
) foreach $role->$get($method_name);
}
}
}
1;
__END__
=pod
=head1 NAME
Moose::Meta::Role::Application::RoleSummation
=head1 DESCRIPTION
Summation composes two traits, forming the union of non-conflicting
bindings and 'disabling' the conflicting bindings
=head2 METHODS
=over 4
=item B<new>
=item B<meta>
=item B<role_params>
=item B<get_exclusions_for_role>
=item B<get_method_aliases_for_role>
=item B<is_aliased_method>
=item B<is_method_aliased>
=item B<is_method_excluded>
=item B<apply>
=item B<check_role_exclusions>
=item B<check_required_methods>
=item B<check_required_attributes>
=item B<apply_attributes>
=item B<apply_methods>
=item B<apply_method_modifiers>
=item B<apply_override_method_modifiers>
=back
=head1 BUGS
All complex software has bugs lurking in it, and this module is no
exception. If you find a bug please either email me, or add the bug
to cpan-RT.
=head1 AUTHOR
Stevan Little E<lt>stevan@iinteractive.comE<gt>
=head1 COPYRIGHT AND LICENSE
Copyright 2006-2008 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=cut