rust-zstd 0.1.0

Pure Rust Zstandard codec — compress + decompress, zero external dependencies
Documentation 
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#[test]
fn compression_ratios_by_level() {
    let patterns: Vec<(&str, Vec<u8>)> = vec![
        ("zeros_64K", vec![0u8; 65536]),
        (
            "text_50K",
            b"The quick brown fox jumps over the lazy dog. ".repeat(1100),
        ),
        (
            "seq_f64_32K",
            (0..4096u64)
                .flat_map(|i| (i as f64 * 0.5).to_le_bytes())
                .collect(),
        ),
    ];

    for (name, data) in &patterns {
        eprintln!("\n{} ({} bytes):", name, data.len());
        for level in [0, 1, 3, 7, 11] {
            let compressed = rust_zstd::compress(data, level);
            let decompressed = rust_zstd::decompress(&compressed)
                .unwrap_or_else(|e| panic!("{} level {} decompress: {}", name, level, e));
            assert_eq!(decompressed.len(), data.len(), "{} level {}", name, level);
            assert_eq!(&decompressed, data, "{} level {}", name, level);
            let ratio = data.len() as f64 / compressed.len() as f64;
            eprintln!(
                "  level {:2}: {:>8} -> {:>8}  ({:.2}x)",
                level,
                data.len(),
                compressed.len(),
                ratio
            );
        }
    }
}