When applying roles, don't apply the exact same role object more than once.

[gitmo/Moose.git] / lib / Moose / Meta / Role / Application / ToRole.pm

diff --git a/lib/Moose/Meta/Role/Application/ToRole.pm b/lib/Moose/Meta/Role/Application/ToRole.pm
index 59d4579..54979f5 100644 (file)
--- a/lib/Moose/Meta/Role/Application/ToRole.pm
+++ b/lib/Moose/Meta/Role/Application/ToRole.pm
@@ -6,15 +6,17 @@ use metaclass;
 
 use Scalar::Util    'blessed';
 
-our $VERSION   = '0.98';
-$VERSION = eval $VERSION;
-our $AUTHORITY = 'cpan:STEVAN';
-
 use base 'Moose::Meta::Role::Application';
 
 sub apply {
     my ($self, $role1, $role2) = @_;
+
+    # We're not checking for role names to support multiple instances of the
+    # same Parameterized role.
+    return if grep { $role1 == $_ } @{ $role2->get_roles() };
+
     $self->SUPER::apply($role1, $role2);
+
     $role2->add_role($role1);
 }
 
@@ -27,7 +29,7 @@ sub check_role_exclusions {
     foreach my $excluded_role_name ($role1->get_excluded_roles_list) {
         if ( $role2->does_role($excluded_role_name) ) {
             require Moose;
-            Moose->throw_error("The class " . $role2->name . " does the excluded role '$excluded_role_name'");
+            Moose->throw_error("The role " . $role2->name . " does the excluded role '$excluded_role_name'");
         }
         $role2->add_excluded_roles($excluded_role_name);
     }
@@ -57,9 +59,15 @@ sub apply_attributes {
             # make sure we haven't seen this one already too
             $role2->get_attribute($attribute_name) != $role1->get_attribute($attribute_name)) {
 
+            my $role2_name = $role2->name;
+
             require Moose;
-            Moose->throw_error("Role '" . $role1->name . "' has encountered an attribute conflict " .
-                    "during composition. This is fatal error and cannot be disambiguated.");
+            Moose->throw_error( "Role '"
+                    . $role1->name
+                    . "' has encountered an attribute conflict"
+                    . " while being composed into '$role2_name'."
+                    . " This is a fatal error and cannot be disambiguated."
+                    . " The conflicting attribute is named '$attribute_name'." );
         }
         else {
             $role2->add_attribute(
@@ -70,14 +78,18 @@ sub apply_attributes {
 }
 
 sub apply_methods {
-    my ($self, $role1, $role2) = @_;
-    foreach my $method_name ($role1->get_method_list) {
-        next if $method_name eq 'meta';
+    my ( $self, $role1, $role2 ) = @_;
+    foreach my $method ( $role1->_get_local_methods ) {
+
+        my $method_name = $method->name;
+
+        next if $method->isa('Class::MOP::Method::Meta');
 
         unless ( $self->is_method_excluded($method_name) ) {
-            if (   $role2->has_method($method_name)
-                && $role2->get_method($method_name)->body
-                != $role1->get_method($method_name)->body ) {
+
+            my $role2_method = $role2->get_method($method_name);
+            if (   $role2_method
+                && $role2_method->body != $method->body ) {
 
                 # method conflicts between roles result in the method becoming
                 # a requirement
@@ -89,30 +101,34 @@ sub apply_methods {
             else {
                 $role2->add_method(
                     $method_name,
-                    $role1->get_method($method_name)
+                    $method,
                 );
             }
         }
 
-        if ($self->is_method_aliased($method_name)) {
-            my $aliased_method_name = $self->get_method_aliases->{$method_name};
+        next unless $self->is_method_aliased($method_name);
 
-            if ($role2->has_method($aliased_method_name) &&
-                $role2->get_method($aliased_method_name)->body != $role1->get_method($method_name)->body) {
+        my $aliased_method_name = $self->get_method_aliases->{$method_name};
 
-                require Moose;
-                Moose->throw_error("Cannot create a method alias if a local method of the same name exists");
-            }
+        my $role2_method = $role2->get_method($aliased_method_name);
+
+        if (   $role2_method
+            && $role2_method->body != $method->body ) {
 
-            $role2->add_method(
-                $aliased_method_name,
-                $role1->get_method($method_name)
+            require Moose;
+            Moose->throw_error(
+                "Cannot create a method alias if a local method of the same name exists"
             );
+        }
 
-            if (!$role2->has_method($method_name)) {
-                $role2->add_required_methods($method_name)
-                    unless $self->is_method_excluded($method_name);
-            }
+        $role2->add_method(
+            $aliased_method_name,
+            $role1->get_method($method_name)
+        );
+
+        if ( !$role2->has_method($method_name) ) {
+            $role2->add_required_methods($method_name)
+                unless $self->is_method_excluded($method_name);
         }
     }
 }
@@ -170,14 +186,12 @@ sub apply_method_modifiers {
 
 1;
 
+# ABSTRACT: Compose a role into another role
+
 __END__
 
 =pod
 
-=head1 NAME
-
-Moose::Meta::Role::Application::ToRole - Compose a role into another role
-
 =head1 DESCRIPTION
 
 =head2 METHODS
@@ -210,18 +224,5 @@ Moose::Meta::Role::Application::ToRole - Compose a role into another role
 
 See L<Moose/BUGS> for details on reporting bugs.
 
-=head1 AUTHOR
-
-Stevan Little E<lt>stevan@iinteractive.comE<gt>
-
-=head1 COPYRIGHT AND LICENSE
-
-Copyright 2006-2010 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