Generic loses literal

const nonEmptyStringOrNull = type("<s extends string>", [
  "s | null | undefined",
  "=>",
  (s) => (!s ? null : s),
]);

const nonEmptyStringOrNull = type("<s extends string>", [
  "s | null | undefined",
  "=>",
  (s) => (!s ? null : s),
]);

const test = type({
test1: nonEmptyStringOrNull("'hi'")
});

const test = type({
test1: nonEmptyStringOrNull("'hi'")
});

test1 is coming back as string | null instead of "hi" | null

Generic loses literal - arktype