Replace the setup_engine workaround with a better one

Instead of letting the .psgi setup_engine('PSGI') and then trying
to undo the damage, add a flag that makes setup_engine not really
load the requested engine if we're in the middle of loading a myapp.psgi

diff --git a/lib/Catalyst.pm b/lib/Catalyst.pm
index 083c0af..2568fdd 100644 (file)
--- a/lib/Catalyst.pm
+++ b/lib/Catalyst.pm
@@ -75,7 +75,7 @@ our $GO        = Catalyst::Exception::Go->new;
 __PACKAGE__->mk_classdata($_)
   for qw/components arguments dispatcher engine log dispatcher_class
   engine_loader context_class request_class response_class stats_class
-  setup_finished _psgi_app/;
+  setup_finished _psgi_app loading_psgi_file/;
 
 __PACKAGE__->dispatcher_class('Catalyst::Dispatcher');
 __PACKAGE__->request_class('Catalyst::Request');
@@ -2618,6 +2618,9 @@ sub setup_engine {
         }),
     );
 
+    # Don't really setup_engine -- see _setup_psgi_app for explanation.
+    return if $class->loading_psgi_file;
+
     my $engine = $class->engine_class;
     Class::MOP::load_class($engine);
 
@@ -2656,27 +2659,20 @@ sub _setup_psgi_app {
         );
 
         next unless -e $psgi_file;
+
+        # If $psgi_file calls ->setup_engine, it's doing so to load
+        # Catalyst::Engine::PSGI. But if it does that, we're only going to
+        # throw away the loaded PSGI-app and load the 5.9 Catalyst::Engine
+        # anyway. So set a flag (ick) that tells setup_engine not to populate
+        # $c->engine or do any other things we might regret.
+
+        $app->loading_psgi_file(1);
         my $psgi_app = Plack::Util::load_psgi($psgi_file);
+        $app->loading_psgi_file(0);
 
         return $psgi_app
             unless $app->engine_loader->needs_psgi_engine_compat_hack;
 
-        # load_psgi ran a .psgi file doing ->setup_engine('PSGI'). That's what
-        # .psgi files generated by the old Engine::PSGI do. Those return an app
-        # coderef calling into MyApp->run, which doesn't work anymore, so we're
-        # just ignoring it and use the wrapped legacy psgi app
-
-        $app->engine(undef);
-        $app->setup_engine;
-
-        # ^^ We need to do this because even though we are discarded $psgi_app, the
-        # fact that it was loaded above means that Catalyst Engine now has the
-        # wrong value (PSGI), which persists due to the singleton nature of all
-        # this stuff.  This solution is probably a lame hack but did work for all
-        # the cases we know about.  Hopefully we can pull out this crap soon
-        # Please note that if the fact that the psgi file was loaded started to set
-        # values in areas outside Engine this hack will probably fail.
-
         warn <<"EOW";
 Found a legacy Catalyst::Engine::PSGI .psgi file at ${psgi_file}.