While upgrading to 0.16200 I noticed plugins that use the before_template hook die with:

[TestApp:23715] error @2015-09-29 18:20:25> Route exception: Can't call method "params" on an undefined value at /usr/local/perlbrew/perls/5.19.3/lib/site_perl/5.19.3/Dancer2/Core/Role/Template.pm line 180. in /usr/local/perlbrew/perls/5.19.3/lib/site_perl/5.19.3/Dancer2/Core/App.pm l. 1273

Example to replicate this:

App (test) code:

use Plack::Test;
use HTTP::Request::Common;

{
    package TestApp;
    use Dancer2;

    hook before_template => sub {
        # do something, or nothing...
    };

    set template => 'template_toolkit';

    get '/' => sub {
        template 't.tt', { hi => "hello" },
    };
};

my $test = Plack::Test->create( TestApp->to_app );
my $res = $test->request(GET "/");

print $res->content;

With a very basic template named views/t.tt

[% hi %]

The problem, I guess, is the order of operations here. When I move the set template => 'template_toolkit'; above the hook, all works as expected, but that'd means I have to use constructs like this to use plugins:

BEGIN {
    use Dancer2;
    set template => 'template_toolkit';
};
use Dancer2::Plugin::Something::That::Adds::A::Hook;

Not ideal.