+=head1 NAME
+
+Catalyst::Upgrading - Instructions for upgrading to the latest Catalyst
+
=head1 Upgrading to Catalyst 5.80
Most applications and plugins should run unaltered on Catalyst 5.80.
=head1 Known backwards compatibility breakages.
+=head2 Issues with Class::C3
+
+Catalyst 5.80 uses L<Algorithm::C3> method dispatch order. This is built into
+perl 5.10, and comes via L<Class::C3> for perl 5.8. This replaces L<NEXT>
+with L<Class::C3::Adopt::NEXT>, forcing all components to resolve methods using
+C3, rather than the unpredictable dispatch order of L<NEXT>.
+
+To be able to do this, however, entails that the graph of superclasses for each
+class must be linearizable using the C3 algorithm. Unfortunately, when
+superclasses are being used as mixins, it is easy to get this wrong.
+
+Most common is the case of:
+
+ package Component1; # Note, this is the common case
+ use base qw/Class::Accessor::Fast Class::Data::Inheritable/;
+
+ package Component2; # Accidentally saying it this way round causes fail.
+ use base qw/Class::Data::Inheritable Class::Accessor::Fast/;
+
+ package GoesBang;
+ use base qw/Component1 Component2/;
+
+And the Catalyst plugin most often causing this, is
+L<Catalyst::Plugin::Session::Store::FastMmap> - if you are using this plugin
+and see issues, then please upgrade!
+
+This can, however, be found in your own application - the only solution is to
+go through each base class of the class the error was reported against, until
+you identify the ones in conflict, and resolve them.
+
=head2 Components which inherit from Moose::Object before Catalyst::Component
Moose components which say:
to use the constructor provided by Moose, whilst working (if you do some hacks
with the C< BUILDARGS > method), will not work with Catalyst 5.80 as
C<Catalyst::Component> inherits from C<Moose::Object>, and so C< @ISA > fails
-to linearise.
+to linearize.
The fix for this is to not inherit directly from C<Moose::Object>
yourself. Having components which do not inherit their constructor from
BEGIN { extends 'Catalyst::Component' }; # Or ::Controller, or whatever
Note that the C< extends > declaration needs to occur in a begin block for
-L<attributes> to operate correctly. You also don't get the L<Moose::Object>
-constructor, and therefore attribute initialization will not work as normally
-expected. If you want to use Moose attributes, then they need to be made lazy
-to correctly initialize.
+L<attributes> to operate correctly.
+
+You also don't get the L<Moose::Object> constructor, and therefore attribute
+initialization will not work as normally expected. If you want to use Moose
+attributes, then they need to be made lazy to correctly initialize.
+
+Note that this only applies if your component needs to maintain component
+backwards compatibility for Catalyst versions before 5.71001 - in 5.71001
+attributes work as expected, and the BUILD method is called normally
+(although BUILDARGS is not).
+
+If you depend on Catalyst 5.8, then B<all> Moose features work as expected.
=head3 use Moose in MyApp
*$full_method_name = subname $full_method_name, sub { ... };
Additionally, you can take advantage of Catalysts use of L<Class::MOP> and
-install the closure using the appropriate metaclass. Example:
+install the closure using the appropriate meta class. Example:
use Class::MOP;
my $metaclass = Moose::Meta::Class->initialize($package_name);
=head2 Hooking into application setup
-To execute code during application startup the following snippet in MyApp.pm
+To execute code during application start-up the following snippet in MyApp.pm
used to work:
sub setup {
... # things to do after the actual setup
};
-The setup_finalize hook was introduced as a way to void this issue.
+The setup_finalize hook was introduced as a way to avoid this issue.
=head2 Components with a new method which returns false
=head1 WARNINGS
+=head2 Catalyst::Base
+
+Any code using L<Catalyst::Base> will now warn, and this module will be removed
+in a future release.
+
=head2 Methods in Catalyst::Dispatcher
The following methods in Catalyst::Dispatcher are both an implementation
adequately supports your use-case, please email the development list to
discuss what API features you need so that you can be appropriately supported.
-=head2 Class naming to packages defined does not correspond.
+=head2 Class files with names that don't correspond to the packages they define
In this version of Catalyst, if a component is loaded from disk, but no
symbols are defined in that component's name space after it is loaded, this
=head2 $c->plugin method
-Calling the plugin method is deprecated, and calling it at runtime is B<highly
+Calling the plugin method is deprecated, and calling it at run time is B<highly
deprecated>.
Instead you are recommended to use L< Catalyst::Model::Adaptor > or similar to