builder.t

use Test2::V0;

package Demo::A {
    use Moo;
    has attr => (
        is      => 'lazy',
        builder => sub { __PACKAGE__ },
    );
};

package Demo::B {
    use Moo;
    extends 'Demo::A';
    sub _build_attr { __PACKAGE__ }
};

subtest builder => sub {
    is(
        Demo::B->new,
        object { call attr => 'Demo::B' },
        'should use the correct builder',
    );
};

done_testing;