foo

[gitmo/MooseX-AttributeHelpers.git] / lib / MooseX / AttributeHelpers / Base.pm

diff --git a/lib/MooseX/AttributeHelpers/Base.pm b/lib/MooseX/AttributeHelpers/Base.pm
index 09ae2f1..93f72fb 100644 (file)
--- a/lib/MooseX/AttributeHelpers/Base.pm
+++ b/lib/MooseX/AttributeHelpers/Base.pm
@@ -1,22 +1,50 @@
 
 package MooseX::AttributeHelpers::Base;
 use Moose;
+use Moose::Util::TypeConstraints;
 
 our $VERSION   = '0.01';
 our $AUTHORITY = 'cpan:STEVAN';
 
 extends 'Moose::Meta::Attribute';
 
-has 'method_constructors' => (
+# this is the method map you define ...
+has 'provides' => (
     is      => 'ro',
     isa     => 'HashRef',
-    default => sub { {} }
+    default => sub {{}}
 );
 
-has 'provides' => (
-    is       => 'ro',
-    isa      => 'HashRef',
-    required => 1,
+
+# these next two are the possible methods 
+# you can use in the 'provides' map.
+
+# provide a Class or Role which we can 
+# collect the method providers from 
+has 'method_provider' => (
+    is        => 'ro',
+    isa       => 'ClassName',
+    predicate => 'has_method_provider',
+);
+
+# or you can provide a HASH ref of anon subs
+# yourself. This will also collect and store
+# the methods from a method_provider as well 
+has 'method_constructors' => (
+    is      => 'ro',
+    isa     => 'HashRef',
+    lazy    => 1,
+    default => sub {
+        my $self = shift;
+        return +{} unless $self->has_method_provider;
+        # or grab them from the role/class
+        my $method_provider = $self->method_provider->meta;
+        return +{
+            map { 
+                $_ => $method_provider->get_method($_)
+            } $method_provider->get_method_list
+        };            
+    }
 );
 
 # extend the parents stuff to make sure 
@@ -24,52 +52,80 @@ has 'provides' => (
 has '+$!default'       => (required => 1);
 has '+type_constraint' => (required => 1);
 
+## Methods called prior to instantiation
+
+sub helper_type { () }
+
+sub process_options_for_provides {
+    my ($self, $options) = @_;
+    
+    if (my $type = $self->helper_type) {
+        (exists $options->{isa})
+            || confess "You must define a type with the $type metaclass";  
+
+        my $isa = $options->{isa};       
+
+        unless (blessed($isa) && $isa->isa('Moose::Meta::TypeConstraint')) {
+            $isa = find_type_constraint($isa);        
+        }
+
+        ($isa->is_a_type_of($type))
+            || confess "The type constraint for a $type ($options->{isa}) must be a subtype of $type";
+    }
+}
+
+before '_process_options' => sub {
+    my ($self, $name, $options) = @_;
+    if (exists $options->{provides} || 
+        exists $options->{isa}      && $options->{isa} =~ /^.*?\[.*?\]$/) {
+        $self->process_options_for_provides($options);
+    }
+};
+
+## methods called after instantiation
+
 # this confirms that provides has 
 # all valid possibilities in it
-sub _check_provides {
+sub check_provides_values {
     my $self = shift;
+    
     my $method_constructors = $self->method_constructors;
+    
     foreach my $key (keys %{$self->provides}) {
         (exists $method_constructors->{$key})
             || confess "$key is an unsupported method type";
     }
 }
 
-# this provides an opportunity to 
-# manipulate the %options to handle
-# some of the provides features 
-# correctly.
-sub _process_options_for_provides {
-    my ($self, $options) = @_;
-    # ...
-}
-
-before '_process_options' => sub {
-    my ($self, $name, $options) = @_;
-    if (exists $options->{provides}) {
-        $self->_process_options_for_provides($options);
-    }
-};
-
 after 'install_accessors' => sub {
     my $attr  = shift;
     my $class = $attr->associated_class;
 
     # before we install them, lets
     # make sure they are valid
-    $attr->_check_provides;    
+    $attr->check_provides_values;    
 
     my $method_constructors = $attr->method_constructors;
     
     foreach my $key (keys %{$attr->provides}) {
-        $class->add_method(
-            $attr->provides->{$key}, 
-            $method_constructors->{$key}->($attr)
+        
+        my $method_name = $attr->provides->{$key};
+        my $method_body = $method_constructors->{$key}->($attr);
+        
+        if ($class->has_method($method_name)) {
+            confess "The method ($method_name) already exists in class (" . $class->name . ")";
+        }
+        
+        $class->add_method($method_name => 
+            MooseX::AttributeHelpers::Meta::Method::Provided->wrap(
+                $method_body,
+            )
         );
     }
 };
 
 no Moose;
+no Moose::Util::TypeConstraints;
 
 1;