const EXPTECTED: &str = "[
/*[0]*/ None,
/*[1]*/ Some([]),
/*[2]*/ Some([
/*[0]*/ 42,
]),
/*[3]*/ Some([
/*[0]*/ 4,
/*[1]*/ 2,
]),
/*[4]*/ None,
]";
const EXPTECTED_COMPACT: &str = "[/*[0]*/ None, /*[1]*/ Some([]), /*[2]*/ Some([/*[0]*/ 42]), \
/*[3]*/ Some([/*[0]*/ 4, /*[1]*/ 2]), /*[4]*/ None]";
#[test]
fn enumerate_arrays() {
let v: Vec