Add illigal inheritance process (Moose 1.09 feature)

[gitmo/Mouse.git] / lib / Mouse / Meta / Attribute.pm

diff --git a/lib/Mouse/Meta/Attribute.pm b/lib/Mouse/Meta/Attribute.pm
index 6d8bb3a..12dead6 100644 (file)
--- a/lib/Mouse/Meta/Attribute.pm
+++ b/lib/Mouse/Meta/Attribute.pm
@@ -192,20 +192,29 @@ sub _throw_type_constraint_error {
     );
 }
 
+sub illegal_options_for_inheritance {
+    return qw(is reader writer accessor clearer predicate);
+}
+
 sub clone_and_inherit_options{
     my $self = shift;
     my $args = $self->Mouse::Object::BUILDARGS(@_);
 
-    my($attribute_class, @traits) = ref($self)->interpolate_class($args);
+    foreach my $illegal($self->illegal_options_for_inheritance) {
+        if(exists $args->{$illegal}) {
+            $self->throw_error("Illegal inherited option: $illegal");
+        }
+    }
 
-    $args->{traits} = \@traits if @traits;
-    # do not inherit the 'handles' attribute
     foreach my $name(keys %{$self}){
-        if(!exists $args->{$name} && $name ne 'handles'){
-            $args->{$name} = $self->{$name};
+        if(!exists $args->{$name}){
+            $args->{$name} = $self->{$name}; # inherit from self
         }
     }
 
+    my($attribute_class, @traits) = ref($self)->interpolate_class($args);
+    $args->{traits} = \@traits if @traits;
+
     # remove temporary caches
     foreach my $attr(keys %{$args}){
         if($attr =~ /\A _/xms){
@@ -213,6 +222,11 @@ sub clone_and_inherit_options{
         }
     }
 
+    # remove default if lazy_build => 1
+    if($args->{lazy_build}) {
+        delete $args->{default};
+    }
+
     return $attribute_class->new($self->name, $args);
 }
 
@@ -329,6 +343,10 @@ sub install_accessors{
         my %handles = $attribute->_canonicalize_handles($attribute->{handles});
 
         while(my($handle, $method_to_call) = each %handles){
+            if($metaclass->has_method($handle)) {
+                $attribute->throw_error("You cannot overwrite a locally defined method ($handle) with a delegation");
+            }
+
             $metaclass->add_method($handle =>
                 $attribute->_make_delegation_method(
                     $handle, $method_to_call));