assertSpyCalls(constraint, 1);
assertStrictEquals(constraint.calls[0].args[0], "etaoin");
assertEquals([...constraint.calls[0].args[1]], ["etaoin", "e"]);
assertSpyCalls(constraint, 1);
assertStrictEquals(constraint.calls[0].args[0], "etaoin");
assertEquals([...constraint.calls[0].args[1]], ["etaoin", "e"]);