https://rt.perl.org/rt3/Public/Bug/Display.html?id=78258

S02-magicals_78258.t

use v6;

BEGIN @*INC.push: 't/spec/S02-magicals/';
use UsedEnv;

env_exists();

S02-magicals_UsedEnv.pm6

module UsedEnv {
    use Test;
    plan 1;
    sub env_exists is export {
        ok %*ENV.exists('PATH'), "env exists in use (RT #78258)";
        done;
    }
}