1 files changed, 310 insertions, 0 deletions
diff --git a/tests/len_prefix.rs b/tests/len_prefix.rs
new file mode 100644
index 0000000..d9597eb
--- /dev/null
+++ b/tests/len_prefix.rs
@@ -0,0 +1,310 @@
+use zr_protocol::{
+    codec::{decode::Decode, encode::Encode},
+    types::prefix::length::LenPrefixed,
+};
+
+fn encode_to_bytes<T: Encode>(value: T) -> Vec<u8> {
+    let mut buf = Vec::new();
+    value.encode(&mut buf).unwrap();
+    buf
+}
+
+// ────────────────────── Données simples ─────────
+
+#[test]
+fn simple_u32_with_u8_length() {
+    let lp = LenPrefixed::<u8, u32>::new(42u32);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x04, 0x00, 0x00, 0x00, 0x2A]);
+}
+
+#[test]
+fn simple_u16_with_u16_length() {
+    let lp = LenPrefixed::<u16, u16>::new(256u16);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x00, 0x02, 0x01, 0x00]);
+}
+
+#[test]
+fn simple_u8_with_u8_length() {
+    let lp = LenPrefixed::<u8, u8>::new(0xABu8);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x01, 0xAB]);
+}
+
+#[test]
+fn simple_u64_with_u32_length() {
+    let lp = LenPrefixed::<u32, u64>::new(0x0102030405060708u64);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(
+        buf,
+        vec![0x00, 0x00, 0x00, 0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08]
+    );
+}
+
+// ────────────────────── Booléen ─────────────────
+
+#[test]
+fn bool_true_with_u8_length() {
+    let lp = LenPrefixed::<u8, bool>::new(true);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x01, 0x01]);
+}
+
+#[test]
+fn bool_false_with_u8_length() {
+    let lp = LenPrefixed::<u8, bool>::new(false);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x01, 0x00]);
+}
+
+// ────────────────────── Tableaux ────────────────
+
+#[test]
+fn array_4_bytes_with_u8_length() {
+    let lp = LenPrefixed::<u8, [u8; 4]>::new([0x01, 0x02, 0x03, 0x04]);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x04, 0x01, 0x02, 0x03, 0x04]);
+}
+
+#[test]
+fn array_16_bytes_with_u16_length() {
+    let data: [u8; 16] = std::array::from_fn(|i| i as u8);
+    let lp = LenPrefixed::<u16, [u8; 16]>::new(data);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf[0..2], [0x00, 0x10]);
+    assert_eq!(&buf[2..], &data[..]);
+}
+
+#[test]
+fn array_256_bytes_with_u16_length() {
+    let data: [u8; 256] = std::array::from_fn(|i| (i % 256) as u8);
+    let lp = LenPrefixed::<u16, [u8; 256]>::new(data);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf[0..2], [0x01, 0x00]);
+    assert_eq!(&buf[2..], &data[..]);
+}
+
+// ────────────────────── Roundtrip ───────────────
+
+#[test]
+fn roundtrip_u32_u8() {
+    let lp = LenPrefixed::<u8, u32>::new(42u32);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u8, u32>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), 42u32);
+}
+
+#[test]
+fn roundtrip_u64_u16() {
+    let lp = LenPrefixed::<u16, u64>::new(u64::MAX);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u16, u64>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), u64::MAX);
+}
+
+#[test]
+fn roundtrip_bool_u8() {
+    let lp = LenPrefixed::<u8, bool>::new(true);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u8, bool>::decode(&mut reader).unwrap();
+    assert!(*decoded.as_ref());
+}
+
+#[test]
+fn roundtrip_array_u8() {
+    let data = [0xDE, 0xAD, 0xBE, 0xEF];
+    let lp = LenPrefixed::<u8, [u8; 4]>::new(data);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u8, [u8; 4]>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), data);
+}
+
+#[test]
+fn roundtrip_negative_i32() {
+    let lp = LenPrefixed::<u8, i32>::new(-12345);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u8, i32>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), -12345);
+}
+
+#[test]
+fn roundtrip_f64() {
+    let lp = LenPrefixed::<u8, f64>::new(3.141592653589793);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u8, f64>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), 3.141592653589793);
+}
+
+#[test]
+fn roundtrip_u128() {
+    let lp = LenPrefixed::<u16, u128>::new(u128::MAX);
+    let buf = encode_to_bytes(lp);
+
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u16, u128>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), u128::MAX);
+}
+
+// ────────────────────── Imbrication ─────────────
+
+#[test]
+fn nested_len_prefixed_u16_u8_u32() {
+    let inner = LenPrefixed::<u8, u32>::new(42u32);
+    let outer = LenPrefixed::<u16, LenPrefixed<u8, u32>>::new(inner);
+    let buf = encode_to_bytes(outer);
+
+    // outer length = 1 (u8 prefix of inner) + 4 (u32) = 5
+    assert_eq!(buf[0..2], [0x00, 0x05]);
+    // inner length = 4
+    assert_eq!(buf[2], 0x04);
+    // inner data = 42
+    assert_eq!(&buf[3..7], &[0x00, 0x00, 0x00, 0x2A]);
+}
+
+#[test]
+fn roundtrip_nested() {
+    let inner = LenPrefixed::<u8, u16>::new(1337u16);
+    let outer = LenPrefixed::<u16, LenPrefixed<u8, u16>>::new(inner);
+    let buf = encode_to_bytes(outer);
+
+    let mut reader = &buf[..];
+    let decoded_outer = LenPrefixed::<u16, LenPrefixed<u8, u16>>::decode(&mut reader).unwrap();
+    let decoded_inner = decoded_outer.as_ref();
+    assert_eq!(decoded_inner.as_ref(), &1337u16);
+}
+
+#[test]
+fn triple_nested() {
+    let l1 = LenPrefixed::<u8, u8>::new(0xAA);
+    let l2 = LenPrefixed::<u8, LenPrefixed<u8, u8>>::new(l1);
+    let l3 = LenPrefixed::<u16, LenPrefixed<u8, LenPrefixed<u8, u8>>>::new(l2);
+    let buf = encode_to_bytes(l3);
+
+    let mut reader = &buf[..];
+    let d3 = LenPrefixed::<u16, LenPrefixed<u8, LenPrefixed<u8, u8>>>::decode(&mut reader).unwrap();
+    let d2 = d3.as_ref();
+    let d1 = d2.as_ref();
+    assert_eq!(*d1.as_ref(), 0xAAu8);
+}
+
+// ────────────────────── Erreurs de décodage ─────
+
+#[test]
+fn decode_empty_buffer_fails() {
+    let result = LenPrefixed::<u8, u32>::decode(&mut &[][..]);
+    assert!(result.is_err());
+}
+
+#[test]
+fn decode_truncated_length_fails() {
+    let result = LenPrefixed::<u16, u32>::decode(&mut &[0x01][..]);
+    assert!(result.is_err());
+}
+
+#[test]
+fn decode_length_exceeds_data_fails() {
+    let mut buf = Vec::new();
+    100u8.encode(&mut buf).unwrap();
+    buf.extend_from_slice(&[0x01, 0x02]);
+    let result = LenPrefixed::<u8, u32>::decode(&mut &buf[..]);
+    assert!(result.is_err());
+}
+
+#[test]
+fn decode_zero_length_with_zero_sized_type() {
+    let lp = LenPrefixed::<u8, [u8; 0]>::new([]);
+    let buf = encode_to_bytes(lp);
+    let mut reader = &buf[..];
+    let decoded = LenPrefixed::<u8, [u8; 0]>::decode(&mut reader).unwrap();
+    assert_eq!(*decoded.as_ref(), []);
+}
+
+// ────────────────────── AsRef / AsMut ───────────
+
+#[test]
+fn as_ref_returns_inner() {
+    let lp = LenPrefixed::<u8, u32>::new(99u32);
+    assert_eq!(*lp.as_ref(), 99u32);
+}
+
+#[test]
+fn as_mut_allows_mutation() {
+    let mut lp = LenPrefixed::<u8, u32>::new(1u32);
+    *lp.as_mut() = 42;
+    assert_eq!(*lp.as_ref(), 42);
+}
+
+// ────────────────────── Taille du buffer ────────
+
+#[test]
+fn u8_length_header_size() {
+    let lp = LenPrefixed::<u8, u8>::new(0);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf.len(), 2); // 1 byte length + 1 byte data
+}
+
+#[test]
+fn u16_length_header_size() {
+    let lp = LenPrefixed::<u16, u8>::new(0);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf.len(), 3); // 2 byte length + 1 byte data
+}
+
+#[test]
+fn u32_length_header_size() {
+    let lp = LenPrefixed::<u32, u8>::new(0);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf.len(), 5); // 4 byte length + 1 byte data
+}
+
+#[test]
+fn u64_length_header_size() {
+    let lp = LenPrefixed::<u64, u8>::new(0);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf.len(), 9); // 8 byte length + 1 byte data
+}
+
+#[test]
+fn large_data_length_correct() {
+    let data: [u8; 1000] = std::array::from_fn(|i| (i % 256) as u8);
+    let lp = LenPrefixed::<u16, [u8; 1000]>::new(data);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf.len(), 2 + 1000);
+    assert_eq!(&buf[0..2], &[0x03, 0xE8]); // 1000 in u16 big-endian
+}
+
+// ────────────────────── Sérialisation exacte ────
+
+#[test]
+fn exact_bytes_u8_prefix() {
+    let lp = LenPrefixed::<u8, u16>::new(256u16);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x02, 0x01, 0x00]);
+}
+
+#[test]
+fn exact_bytes_negative_i16() {
+    let lp = LenPrefixed::<u8, i16>::new(-1);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x02, 0xFF, 0xFF]);
+}
+
+#[test]
+fn exact_bytes_zero_u32() {
+    let lp = LenPrefixed::<u8, u32>::new(0u32);
+    let buf = encode_to_bytes(lp);
+    assert_eq!(buf, vec![0x04, 0x00, 0x00, 0x00, 0x00]);
+}