Panic in suffix_array::sais::build_suffix_array

[ajalab]

    #[test]
    fn tmp_build_suffix_array_panic() {
        let text = vec![2u8, 0, 7, 6, 6, 6, 7, 0, 6, 0];
        let converter = IdConverter::new::<u8>();
        let suffix_array = build_suffix_array(&text, &converter);
    }

Stacktrace

---- suffix_array::sais::tests::tmp_build_suffix_array_panic stdout ----
thread 'suffix_array::sais::tests::tmp_build_suffix_array_panic' panicked at src/suffix_array/sais.rs:255:9:
attempt to subtract with overflow
stack backtrace:
   0: rust_begin_unwind
             at /rustc/f6e511eec7342f59a25f7c0534f1dbea00d01b14/library/std/src/panicking.rs:662:5
   1: core::panicking::panic_fmt
             at /rustc/f6e511eec7342f59a25f7c0534f1dbea00d01b14/library/core/src/panicking.rs:74:14
   2: core::panicking::panic_const::panic_const_sub_overflow
             at /rustc/f6e511eec7342f59a25f7c0534f1dbea00d01b14/library/core/src/panicking.rs:181:21
   3: fm_index::suffix_array::sais::sais_sub
             at ./src/suffix_array/sais.rs:255:9
   4: fm_index::suffix_array::sais::sais_sub
             at ./src/suffix_array/sais.rs:261:13
   5: fm_index::suffix_array::sais::build_suffix_array
             at ./src/suffix_array/sais.rs:148:13
   6: fm_index::suffix_array::sais::tests::tmp_build_suffix_array_panic
             at ./src/suffix_array/sais.rs:476:28
   7: fm_index::suffix_array::sais::tests::tmp_build_suffix_array_panic::{{closure}}
             at ./src/suffix_array/sais.rs:472:38
   8: core::ops::function::FnOnce::call_once
             at /rustc/f6e511eec7342f59a25f7c0534f1dbea00d01b14/library/core/src/ops/function.rs:250:5
   9: core::ops::function::FnOnce::call_once
             at /rustc/f6e511eec7342f59a25f7c0534f1dbea00d01b14/library/core/src/ops/function.rs:250:5

It aborts at the subtraction from i.

fm-index/src/suffix_array/sais.rs

Lines 248 to 256 in a88db3b

	let mut i = sa.len() - 1;
	let mut j = 0;
	while j < lms_len {
	if sa[i] < u64::MAX {
	sa[sa.len() - 1 - j] = sa[i];
	j += 1;
	}
	i -= 1;
	}