Etag 的单测跑不通

[Jetsly]

单测地址 : https://github.com/qiniu/rust-sdk/blob/master/etag/src/etag.rs#L222

#[cfg(test)]
mod tests {
    use qiniu_etag::{prelude::*, EtagV1, EtagV2};
    use std::{boxed::Box, error::Error, result::Result};

    mod utils {
        const FAKE_DATA: [u8; 4096] = make_fake_data();

        pub(super) fn data_of_size(size: usize) -> Vec<u8> {
            let mut buffer = Vec::with_capacity(size);
            let mut rest = size;

            while rest > 0 {
                let add_size = rest.min(FAKE_DATA.len());
                buffer.extend_from_slice(&FAKE_DATA[..add_size]);
                rest -= add_size;
            }
            buffer
        }

        const fn make_fake_data() -> [u8; 4096] {
            let mut buf = [b'b'; 4096];
            buf[0] = b'A';
            buf[4094] = b'\r';
            buf[4095] = b'\n';
            buf
        }
    }

    #[test]
    fn test_etag_v2() -> Result<(), Box<dyn Error>> {
        let mut etag_v1 = EtagV1::default();
        let mut etag_v2 = EtagV2::default();
        etag_v1.update(&utils::data_of_size(1 << 22));
        etag_v2.update(&utils::data_of_size(1 << 22));
        etag_v1.update(&utils::data_of_size(1 << 22));
        etag_v2.update(&utils::data_of_size(1 << 22));
        etag_v1.update(&utils::data_of_size(1 << 20));
        etag_v2.update(&utils::data_of_size(1 << 20));
        assert_eq!(
            etag_v1.finalize_fixed().as_slice(),
            etag_v2.finalize_fixed().as_slice(),
        );
        Ok(())
    }
}

1. 看逻辑当 https://github.com/qiniu/rust-sdk/blob/master/etag/src/etag_v2.rs#L47 长度不等于固定大小的时候，下一次就不会用etagv1
2. 输出的结果 https://github.com/qiniu/rust-sdk/blob/master/etag/src/etag_v2.rs#L94 前缀就不会一样

[bachue]

好的，这个之后会修复的。