From: Stevan Little <stevan.little@iinteractive.com>
Date: Fri, 21 Apr 2006 14:49:15 +0000 (+0000)
Subject: find_attribute_by_name
X-Git-Tag: 0_26~7
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=058c1cf58078cdd0fcb9aa2f4a5c7556e0b8c23a;p=gitmo%2FClass-MOP.git

find_attribute_by_name
---

diff --git a/lib/Class/MOP/Class.pm b/lib/Class/MOP/Class.pm
index 91fcf3b..fc3626e 100644
--- a/lib/Class/MOP/Class.pm
+++ b/lib/Class/MOP/Class.pm
@@ -532,6 +532,24 @@ sub compute_all_applicable_attributes {
     return @attrs;    
 }
 
+sub find_attribute_by_name {
+    my ($self, $attr_name) = @_;
+    # keep a record of what we have seen
+    # here, this will handle all the 
+    # inheritence issues because we are 
+    # using the &class_precedence_list
+    my %seen_class;
+    foreach my $class ($self->class_precedence_list()) {
+        next if $seen_class{$class};
+        $seen_class{$class}++;
+        # fetch the meta-class ...
+        my $meta = $self->initialize($class);
+        return $meta->get_attribute($attr_name)
+            if $meta->has_attribute($attr_name);
+    }
+    return;
+}
+
 # Class attributes
 
 sub add_package_variable {
@@ -1110,6 +1128,12 @@ HASH reference like C<compute_all_applicable_methods> because all
 that same information is discoverable through the attribute 
 meta-object itself.
 
+=item B<find_attribute_by_name ($attr_name)>
+
+This method will traverse the inheritance heirachy and find the 
+first attribute whose name matches C<$attr_name>, then return it. 
+It will return undef if nothing is found.
+
 =back
 
 =head2 Package Variables
diff --git a/t/005_attributes.t b/t/005_attributes.t
index d1ac414..63158f1 100644
--- a/t/005_attributes.t
+++ b/t/005_attributes.t
@@ -3,7 +3,7 @@
 use strict;
 use warnings;
 
-use Test::More tests => 40;
+use Test::More tests => 43;
 use Test::Exception;
 
 BEGIN { 
@@ -78,6 +78,10 @@ my $BAR_ATTR_2 = Class::MOP::Attribute->new('$bar');
     my $meta = Baz->meta;
     isa_ok($meta, 'Class::MOP::Class');
     
+    is($meta->find_attribute_by_name('$bar'), $BAR_ATTR, '... got the right attribute for "bar"');
+    is($meta->find_attribute_by_name('$baz'), $BAZ_ATTR, '... got the right attribute for "baz"');    
+    is($meta->find_attribute_by_name('$foo'), $FOO_ATTR, '... got the right attribute for "foo"');    
+    
     is_deeply(
         [ sort { $a->name cmp $b->name } $meta->compute_all_applicable_attributes() ],
         [ 
diff --git a/t/010_self_introspection.t b/t/010_self_introspection.t
index 1bd53cf..a59ef86 100644
--- a/t/010_self_introspection.t
+++ b/t/010_self_introspection.t
@@ -3,7 +3,7 @@
 use strict;
 use warnings;
 
-use Test::More tests => 134;
+use Test::More tests => 136;
 use Test::Exception;
 
 BEGIN {
@@ -43,7 +43,7 @@ my @methods = qw(
 	add_before_method_modifier add_after_method_modifier add_around_method_modifier
 
     has_attribute get_attribute add_attribute remove_attribute
-    get_attribute_list get_attribute_map compute_all_applicable_attributes
+    get_attribute_list get_attribute_map compute_all_applicable_attributes find_attribute_by_name
     
     add_package_variable get_package_variable has_package_variable remove_package_variable
     );