rust/library/alloctests/tests/num.rs

use core::fmt::NumBuffer;
use std::str::FromStr;

macro_rules! assert_nb {
    ($int:ident, $value:expr) => {
        let value: $int = $value;
        let s = value.to_string();
        let s2 = format!("s: {}.", value);

        assert_eq!(format!("s: {s}."), s2);
        let Ok(ret) = $int::from_str(&s) else {
            panic!("failed to convert into to string");
        };
        assert_eq!(ret, value);

        let mut buffer = NumBuffer::<$int>::new();
        assert_eq!(value.format_into(&mut buffer), s.as_str());
    };
}

macro_rules! uint_to_s {
    ($($fn_name:ident, $int:ident,)+) => {
        $(
            #[test]
            fn $fn_name() {
                assert_nb!($int, $int::MIN);
                assert_nb!($int, $int::MAX);
                assert_nb!($int, 1);
                assert_nb!($int, $int::MIN / 2);
                assert_nb!($int, $int::MAX / 2);
            }
        )+
    }
}
macro_rules! int_to_s {
    ($($fn_name:ident, $int:ident,)+) => {
        $(
            #[test]
            fn $fn_name() {
                assert_nb!($int, $int::MIN);
                assert_nb!($int, $int::MAX);
                assert_nb!($int, 1);
                assert_nb!($int, 0);
                assert_nb!($int, -1);
                assert_nb!($int, $int::MIN / 2);
                assert_nb!($int, $int::MAX / 2);
            }
        )+
    }
}

int_to_s!(
    test_i8_to_string,
    i8,
    test_i16_to_string,
    i16,
    test_i32_to_string,
    i32,
    test_i64_to_string,
    i64,
    test_isize_to_string,
    isize,
    test_i128_to_string,
    i128,
);
uint_to_s!(
    test_u8_to_string,
    u8,
    test_u16_to_string,
    u16,
    test_u32_to_string,
    u32,
    test_u64_to_string,
    u64,
    test_usize_to_string,
    usize,
    test_u128_to_string,
    u128,
);