Allow trigger on ro (or no-accessor) attributes

diff --git a/Changes b/Changes
index 0247d44..5889fad 100644 (file)
--- a/Changes
+++ b/Changes
@@ -20,6 +20,11 @@ Revision history for Perl extension Moose
           is currently not supported in roles, 
           but, ... patches welcome
     
+    * Moose::Meta::Attribute
+      - trigger on a ro-attribute is no longer an
+        error, as it's useful to trigger off of the
+        constructor
+
     * Moose::Meta::Class
       - added same 'add_package_symbol' fix as in 
         Class::MOP 0.56

diff --git a/lib/Moose/Meta/Attribute.pm b/lib/Moose/Meta/Attribute.pm
index 1707392..a2bbfdb 100644 (file)
--- a/lib/Moose/Meta/Attribute.pm
+++ b/lib/Moose/Meta/Attribute.pm
@@ -209,14 +209,9 @@ sub _process_options {
     if (exists $options->{is}) {
         if ($options->{is} eq 'ro') {
             $options->{reader} ||= $name;
-            (!exists $options->{trigger})
-                || confess "Cannot have a trigger on a read-only attribute $name";
         }
         elsif ($options->{is} eq 'rw') {
             $options->{accessor} = $name;
-            ((reftype($options->{trigger}) || '') eq 'CODE')
-                || confess "Trigger must be a CODE ref"
-                    if exists $options->{trigger};
         }
         else {
             confess "I do not understand this option (is => " . $options->{is} . ") on attribute $name"
@@ -259,6 +254,11 @@ sub _process_options {
             if $options->{weak_ref};
     }
 
+    if (exists $options->{trigger}) {
+        (reftype($options->{trigger}) || '') eq 'CODE'
+            || confess "Trigger must be a CODE ref";
+    }
+
     if (exists $options->{auto_deref} && $options->{auto_deref}) {
         (exists $options->{type_constraint})
             || confess "You cannot auto-dereference without specifying a type constraint on attribute $name";

diff --git a/t/020_attributes/004_attribute_triggers.t b/t/020_attributes/004_attribute_triggers.t
index 0a744a5..b5cf34e 100644 (file)
--- a/t/020_attributes/004_attribute_triggers.t
+++ b/t/020_attributes/004_attribute_triggers.t
@@ -5,7 +5,7 @@ use warnings;
 
 use Scalar::Util 'isweak';
 
-use Test::More tests => 27;
+use Test::More tests => 26;
 use Test::Exception;
 
 BEGIN {
@@ -109,15 +109,6 @@ BEGIN {
     use Moose;
     
     ::dies_ok { 
-        has('bling' => (is => 'ro', trigger => sub { 0 }));
-    } '... cannot create trigger on a read-only attr';
-}
-
-{
-    package Bling::Bling;
-    use Moose;
-    
-    ::dies_ok { 
         has('bling' => (is => 'rw', trigger => 'Fail'));
     } '... a trigger must be a CODE ref';