Back out 97036ab72558 which inappropriately compared turds to third parties.
1 load(libdir + "eqArrayHelper.js");
8 [3, ...[t(1)],, ...[t(2), t(3)], 34, 42, ...[t(4)]];
9 assertEqArray(check, [1, 2, 3, 4]);
12 assertEqArray([...arr, arr.pop()], [1, 2, 3, 3]);