From: Yuval Kogman <nothingmuch@woobling.org>
Date: Wed, 18 Jun 2008 07:17:09 +0000 (+0000)
Subject: clone_{object,instance}
X-Git-Tag: 0.19~288
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=7a59f4e85d2dadb67b6ce3112a9066cb8696611a;p=gitmo%2FMouse.git

clone_{object,instance}
---

diff --git a/lib/Mouse/Meta/Class.pm b/lib/Mouse/Meta/Class.pm
index 0d70166..6c94c93 100644
--- a/lib/Mouse/Meta/Class.pm
+++ b/lib/Mouse/Meta/Class.pm
@@ -4,6 +4,7 @@ use strict;
 use warnings;
 
 use Scalar::Util 'blessed';
+use Carp 'confess';
 
 use MRO::Compat;
 
@@ -83,6 +84,37 @@ sub get_attribute     { $_[0]->{attributes}->{$_[1]} }
 
 sub linearized_isa { @{ mro::get_linear_isa($_[0]->name) } }
 
+sub clone_object {
+    my $class    = shift;
+    my $instance = shift;
+
+    (blessed($instance) && $instance->isa($class->name))
+        || confess "You must pass an instance ($instance) of the metaclass (" . $class->name . ")";
+
+    $class->clone_instance($instance, @_);
+}
+
+sub clone_instance {
+    my ($class, $instance, %params) = @_;
+
+    (blessed($instance))
+        || confess "You can only clone instances, \$self is not a blessed instance";
+
+    my $clone = bless { %$instance }, ref $instance;
+
+    foreach my $attr ($class->compute_all_applicable_attributes()) {
+        if ( defined( my $init_arg = $attr->init_arg ) ) {
+            if (exists $params{$init_arg}) {
+                $clone->{ $attr->name } = $params{$init_arg};
+            }
+        }
+    }
+
+    return $clone;
+
+}
+
+
 1;
 
 __END__
diff --git a/t/031-clone.t b/t/031-clone.t
new file mode 100644
index 0000000..44b9ce0
--- /dev/null
+++ b/t/031-clone.t
@@ -0,0 +1,38 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+use Test::More 'no_plan';
+
+{
+    package Foo;
+    use Mouse;
+
+    has foo => (
+        isa => "Str",
+        is  => "rw",
+        default => "foo",
+    );
+
+    has bar => (
+        isa => "ArrayRef",
+        is  => "rw",
+    );
+
+    sub clone {
+        my ( $self, @args ) = @_;
+        $self->meta->clone_object( $self, @args );
+    }
+}
+
+my $foo = Foo->new( bar => [ 1, 2, 3 ] );
+
+is( $foo->foo, "foo", "attr 1", );
+is_deeply( $foo->bar, [ 1 .. 3 ], "attr 2" );
+
+my $clone = $foo->clone( foo => "dancing" );
+
+is( $clone->foo, "dancing", "overridden attr" );
+is_deeply( $clone->bar, [ 1 .. 3 ], "clone attr" );
+