JSTests/microbenchmarks/for-in-on-object-with-lazily-materialized-properties.js

function foo(o) {
    var count = 0;
    for (var p in o) {
        if (o[p])
            count ++;
    }
    return count;
}
noInline(foo);

var total = 0;
for (let j = 0; j < 100000; ++j)
    total += foo(new Error);