Note to self: suppressing the object file when compiling Mason components for testing is keen.
my $interp = HTML::Mason::Interp->new( allow_globals => [ qw($r %session) ], comp_root => _web_path(), out_method => \my $buffer, use_object_files => 0, );
Trying to figure out why the source filter doesn't filter the non-existent object file is not keen.