mismall 2.0.0

Streaming Huffman compression library with AES-256-GCM encryption and archive support
Documentation 
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#[cfg(test)]
use crate::huffman::{
    freq::compute_frequencies,
    tree::{build_huffman_tree, Node},
};
use std::io::Cursor;

#[test]
fn tree_empty_returns_none() {
    let freq = [0u64; 256];
    assert!(build_huffman_tree(&freq).is_none())
}

#[test]
fn tree_single_symbol() {
    let mut freq = [0u64; 256];
    freq[42] = 10;
    let root = build_huffman_tree(&freq).unwrap();

    assert_eq!(root.weight, 10);
    assert_eq!(root.symbol, Some(42));
    assert!(root.left.is_none() && root.right.is_none());
}

#[test]
fn tree_hellow_world_total_weight() {
    let buf = b"hello world";
    let mut cursor = Cursor::new(buf);
    let (freq, _, _) = compute_frequencies(&mut cursor).unwrap();
    let root = build_huffman_tree(&freq).unwrap();

    assert_eq!(root.weight, buf.len() as u64);
}

#[test]
fn tree_leaf_weights_sum_to_root() {
    let mut freq = [0u64; 256];
    freq[0] = 3;
    freq[1] = 2;
    freq[2] = 1;

    let root = build_huffman_tree(&freq).unwrap();

    fn recurse(n: &Node) -> u64 {
        if n.symbol.is_some() {
            return n.weight;
        }
        recurse(n.left.as_ref().unwrap()) + recurse(n.right.as_ref().unwrap())
    }

    let leaf_sum = recurse(&root);
    assert_eq!(leaf_sum, root.weight);
}