[Catalyst] Another thread about porting to CataMoose

[Tomas Doran]

J. Shirley wrote:
> While an obvious blunder to make while coding, I wasn't alerted to 
> anything and the application started with no warnings and no indication 
> that something was wrong.  The only thing is that my 'rpx' method no 
> longer was dispatchable.
> 
> Oops.

Hmm, I think that this is actually by design:

http://search.cpan.org/~drolsky/Moose-0.79/lib/Moose/Manual/FAQ.pod#I_created_an_attribute,_where_are_my_accessors?

I'm sure there is a better explanation somewhere, but I can't find it 
right now.

> So, I'm pretty far out of my depth for 5.8 but I'd be happy to commit a 
> failing test case -- is the proper test case a situation like this, and 
> failing if the method doesn't define a dispatchable path or something 
> else?  I can imagine this is something that could commonly come up and 
> bite people who aren't careful (or working with thick controllers)

I don't think there's any great way to get around this which I can think 
of right now.

The best solution I could come up with is to make Catalyst::Controller 
apply a default attribute trait which warned when (Moose) attributes 
were added which overrode methods with (perl) attributes.

If you'd like to commit TODO tests (there is already a Moose specific 
controller in the test suite) which test for an appropriate warning 
being emitted during app startup, then I'll have a crack at seeing if I 
can do something sane enough to be maintainable..

 > package MyApp::Controller::Auth;
 >
 > use parent 'Catalyst::Controller';
 >
 > use Moose;
 >
 > has 'rpx' => ( is => 'rw' );
 >
 > sub rpx : Chained('/') Args(0) { }
 >
 > 1;

Note this pattern works, but is mildly disrecommended going forwards. 
There are tests in the test suite that it works in basic cases, but it's 
not what people are using - so I wouldn't be confident it will stay 
working for non-trivial cases (I have already fixed bugs with doing it 
this way round).

My Moose native controllers look like this:

package MyApp::Controller::Auth;
use Moose;
use namespace::autoclean;

BEGIN { extends 'Catalyst::Controller'; }

# Attributes and actions

__PACKAGE__->meta->make_immutable; # Note this returns true, so is good 
for the last line

I did scribble _some_ stuff in Catalyst::Manual::ExtendingCatalyst about 
this, but if you'd like to add anything (or at least tell us what it's 
missing currently), that'd be awesome?

Cheers
t0m