1 files changed, 497 insertions, 0 deletions
diff --git a/compiler/rustc_data_structures/src/sip128/tests.rs b/compiler/rustc_data_structures/src/sip128/tests.rs
new file mode 100644
index 000000000..5fe967c41
--- /dev/null
+++ b/compiler/rustc_data_structures/src/sip128/tests.rs
@@ -0,0 +1,497 @@
+use super::*;
+
+use std::hash::{Hash, Hasher};
+
+// Hash just the bytes of the slice, without length prefix
+struct Bytes<'a>(&'a [u8]);
+
+impl<'a> Hash for Bytes<'a> {
+    #[allow(unused_must_use)]
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        for byte in self.0 {
+            state.write_u8(*byte);
+        }
+    }
+}
+
+fn hash_with<T: Hash>(mut st: SipHasher128, x: &T) -> (u64, u64) {
+    x.hash(&mut st);
+    st.finish128()
+}
+
+fn hash<T: Hash>(x: &T) -> (u64, u64) {
+    hash_with(SipHasher128::new_with_keys(0, 0), x)
+}
+
+const TEST_VECTOR: [[u8; 16]; 64] = [
+    [
+        0xa3, 0x81, 0x7f, 0x04, 0xba, 0x25, 0xa8, 0xe6, 0x6d, 0xf6, 0x72, 0x14, 0xc7, 0x55, 0x02,
+        0x93,
+    ],
+    [
+        0xda, 0x87, 0xc1, 0xd8, 0x6b, 0x99, 0xaf, 0x44, 0x34, 0x76, 0x59, 0x11, 0x9b, 0x22, 0xfc,
+        0x45,
+    ],
+    [
+        0x81, 0x77, 0x22, 0x8d, 0xa4, 0xa4, 0x5d, 0xc7, 0xfc, 0xa3, 0x8b, 0xde, 0xf6, 0x0a, 0xff,
+        0xe4,
+    ],
+    [
+        0x9c, 0x70, 0xb6, 0x0c, 0x52, 0x67, 0xa9, 0x4e, 0x5f, 0x33, 0xb6, 0xb0, 0x29, 0x85, 0xed,
+        0x51,
+    ],
+    [
+        0xf8, 0x81, 0x64, 0xc1, 0x2d, 0x9c, 0x8f, 0xaf, 0x7d, 0x0f, 0x6e, 0x7c, 0x7b, 0xcd, 0x55,
+        0x79,
+    ],
+    [
+        0x13, 0x68, 0x87, 0x59, 0x80, 0x77, 0x6f, 0x88, 0x54, 0x52, 0x7a, 0x07, 0x69, 0x0e, 0x96,
+        0x27,
+    ],
+    [
+        0x14, 0xee, 0xca, 0x33, 0x8b, 0x20, 0x86, 0x13, 0x48, 0x5e, 0xa0, 0x30, 0x8f, 0xd7, 0xa1,
+        0x5e,
+    ],
+    [
+        0xa1, 0xf1, 0xeb, 0xbe, 0xd8, 0xdb, 0xc1, 0x53, 0xc0, 0xb8, 0x4a, 0xa6, 0x1f, 0xf0, 0x82,
+        0x39,
+    ],
+    [
+        0x3b, 0x62, 0xa9, 0xba, 0x62, 0x58, 0xf5, 0x61, 0x0f, 0x83, 0xe2, 0x64, 0xf3, 0x14, 0x97,
+        0xb4,
+    ],
+    [
+        0x26, 0x44, 0x99, 0x06, 0x0a, 0xd9, 0xba, 0xab, 0xc4, 0x7f, 0x8b, 0x02, 0xbb, 0x6d, 0x71,
+        0xed,
+    ],
+    [
+        0x00, 0x11, 0x0d, 0xc3, 0x78, 0x14, 0x69, 0x56, 0xc9, 0x54, 0x47, 0xd3, 0xf3, 0xd0, 0xfb,
+        0xba,
+    ],
+    [
+        0x01, 0x51, 0xc5, 0x68, 0x38, 0x6b, 0x66, 0x77, 0xa2, 0xb4, 0xdc, 0x6f, 0x81, 0xe5, 0xdc,
+        0x18,
+    ],
+    [
+        0xd6, 0x26, 0xb2, 0x66, 0x90, 0x5e, 0xf3, 0x58, 0x82, 0x63, 0x4d, 0xf6, 0x85, 0x32, 0xc1,
+        0x25,
+    ],
+    [
+        0x98, 0x69, 0xe2, 0x47, 0xe9, 0xc0, 0x8b, 0x10, 0xd0, 0x29, 0x93, 0x4f, 0xc4, 0xb9, 0x52,
+        0xf7,
+    ],
+    [
+        0x31, 0xfc, 0xef, 0xac, 0x66, 0xd7, 0xde, 0x9c, 0x7e, 0xc7, 0x48, 0x5f, 0xe4, 0x49, 0x49,
+        0x02,
+    ],
+    [
+        0x54, 0x93, 0xe9, 0x99, 0x33, 0xb0, 0xa8, 0x11, 0x7e, 0x08, 0xec, 0x0f, 0x97, 0xcf, 0xc3,
+        0xd9,
+    ],
+    [
+        0x6e, 0xe2, 0xa4, 0xca, 0x67, 0xb0, 0x54, 0xbb, 0xfd, 0x33, 0x15, 0xbf, 0x85, 0x23, 0x05,
+        0x77,
+    ],
+    [
+        0x47, 0x3d, 0x06, 0xe8, 0x73, 0x8d, 0xb8, 0x98, 0x54, 0xc0, 0x66, 0xc4, 0x7a, 0xe4, 0x77,
+        0x40,
+    ],
+    [
+        0xa4, 0x26, 0xe5, 0xe4, 0x23, 0xbf, 0x48, 0x85, 0x29, 0x4d, 0xa4, 0x81, 0xfe, 0xae, 0xf7,
+        0x23,
+    ],
+    [
+        0x78, 0x01, 0x77, 0x31, 0xcf, 0x65, 0xfa, 0xb0, 0x74, 0xd5, 0x20, 0x89, 0x52, 0x51, 0x2e,
+        0xb1,
+    ],
+    [
+        0x9e, 0x25, 0xfc, 0x83, 0x3f, 0x22, 0x90, 0x73, 0x3e, 0x93, 0x44, 0xa5, 0xe8, 0x38, 0x39,
+        0xeb,
+    ],
+    [
+        0x56, 0x8e, 0x49, 0x5a, 0xbe, 0x52, 0x5a, 0x21, 0x8a, 0x22, 0x14, 0xcd, 0x3e, 0x07, 0x1d,
+        0x12,
+    ],
+    [
+        0x4a, 0x29, 0xb5, 0x45, 0x52, 0xd1, 0x6b, 0x9a, 0x46, 0x9c, 0x10, 0x52, 0x8e, 0xff, 0x0a,
+        0xae,
+    ],
+    [
+        0xc9, 0xd1, 0x84, 0xdd, 0xd5, 0xa9, 0xf5, 0xe0, 0xcf, 0x8c, 0xe2, 0x9a, 0x9a, 0xbf, 0x69,
+        0x1c,
+    ],
+    [
+        0x2d, 0xb4, 0x79, 0xae, 0x78, 0xbd, 0x50, 0xd8, 0x88, 0x2a, 0x8a, 0x17, 0x8a, 0x61, 0x32,
+        0xad,
+    ],
+    [
+        0x8e, 0xce, 0x5f, 0x04, 0x2d, 0x5e, 0x44, 0x7b, 0x50, 0x51, 0xb9, 0xea, 0xcb, 0x8d, 0x8f,
+        0x6f,
+    ],
+    [
+        0x9c, 0x0b, 0x53, 0xb4, 0xb3, 0xc3, 0x07, 0xe8, 0x7e, 0xae, 0xe0, 0x86, 0x78, 0x14, 0x1f,
+        0x66,
+    ],
+    [
+        0xab, 0xf2, 0x48, 0xaf, 0x69, 0xa6, 0xea, 0xe4, 0xbf, 0xd3, 0xeb, 0x2f, 0x12, 0x9e, 0xeb,
+        0x94,
+    ],
+    [
+        0x06, 0x64, 0xda, 0x16, 0x68, 0x57, 0x4b, 0x88, 0xb9, 0x35, 0xf3, 0x02, 0x73, 0x58, 0xae,
+        0xf4,
+    ],
+    [
+        0xaa, 0x4b, 0x9d, 0xc4, 0xbf, 0x33, 0x7d, 0xe9, 0x0c, 0xd4, 0xfd, 0x3c, 0x46, 0x7c, 0x6a,
+        0xb7,
+    ],
+    [
+        0xea, 0x5c, 0x7f, 0x47, 0x1f, 0xaf, 0x6b, 0xde, 0x2b, 0x1a, 0xd7, 0xd4, 0x68, 0x6d, 0x22,
+        0x87,
+    ],
+    [
+        0x29, 0x39, 0xb0, 0x18, 0x32, 0x23, 0xfa, 0xfc, 0x17, 0x23, 0xde, 0x4f, 0x52, 0xc4, 0x3d,
+        0x35,
+    ],
+    [
+        0x7c, 0x39, 0x56, 0xca, 0x5e, 0xea, 0xfc, 0x3e, 0x36, 0x3e, 0x9d, 0x55, 0x65, 0x46, 0xeb,
+        0x68,
+    ],
+    [
+        0x77, 0xc6, 0x07, 0x71, 0x46, 0xf0, 0x1c, 0x32, 0xb6, 0xb6, 0x9d, 0x5f, 0x4e, 0xa9, 0xff,
+        0xcf,
+    ],
+    [
+        0x37, 0xa6, 0x98, 0x6c, 0xb8, 0x84, 0x7e, 0xdf, 0x09, 0x25, 0xf0, 0xf1, 0x30, 0x9b, 0x54,
+        0xde,
+    ],
+    [
+        0xa7, 0x05, 0xf0, 0xe6, 0x9d, 0xa9, 0xa8, 0xf9, 0x07, 0x24, 0x1a, 0x2e, 0x92, 0x3c, 0x8c,
+        0xc8,
+    ],
+    [
+        0x3d, 0xc4, 0x7d, 0x1f, 0x29, 0xc4, 0x48, 0x46, 0x1e, 0x9e, 0x76, 0xed, 0x90, 0x4f, 0x67,
+        0x11,
+    ],
+    [
+        0x0d, 0x62, 0xbf, 0x01, 0xe6, 0xfc, 0x0e, 0x1a, 0x0d, 0x3c, 0x47, 0x51, 0xc5, 0xd3, 0x69,
+        0x2b,
+    ],
+    [
+        0x8c, 0x03, 0x46, 0x8b, 0xca, 0x7c, 0x66, 0x9e, 0xe4, 0xfd, 0x5e, 0x08, 0x4b, 0xbe, 0xe7,
+        0xb5,
+    ],
+    [
+        0x52, 0x8a, 0x5b, 0xb9, 0x3b, 0xaf, 0x2c, 0x9c, 0x44, 0x73, 0xcc, 0xe5, 0xd0, 0xd2, 0x2b,
+        0xd9,
+    ],
+    [
+        0xdf, 0x6a, 0x30, 0x1e, 0x95, 0xc9, 0x5d, 0xad, 0x97, 0xae, 0x0c, 0xc8, 0xc6, 0x91, 0x3b,
+        0xd8,
+    ],
+    [
+        0x80, 0x11, 0x89, 0x90, 0x2c, 0x85, 0x7f, 0x39, 0xe7, 0x35, 0x91, 0x28, 0x5e, 0x70, 0xb6,
+        0xdb,
+    ],
+    [
+        0xe6, 0x17, 0x34, 0x6a, 0xc9, 0xc2, 0x31, 0xbb, 0x36, 0x50, 0xae, 0x34, 0xcc, 0xca, 0x0c,
+        0x5b,
+    ],
+    [
+        0x27, 0xd9, 0x34, 0x37, 0xef, 0xb7, 0x21, 0xaa, 0x40, 0x18, 0x21, 0xdc, 0xec, 0x5a, 0xdf,
+        0x89,
+    ],
+    [
+        0x89, 0x23, 0x7d, 0x9d, 0xed, 0x9c, 0x5e, 0x78, 0xd8, 0xb1, 0xc9, 0xb1, 0x66, 0xcc, 0x73,
+        0x42,
+    ],
+    [
+        0x4a, 0x6d, 0x80, 0x91, 0xbf, 0x5e, 0x7d, 0x65, 0x11, 0x89, 0xfa, 0x94, 0xa2, 0x50, 0xb1,
+        0x4c,
+    ],
+    [
+        0x0e, 0x33, 0xf9, 0x60, 0x55, 0xe7, 0xae, 0x89, 0x3f, 0xfc, 0x0e, 0x3d, 0xcf, 0x49, 0x29,
+        0x02,
+    ],
+    [
+        0xe6, 0x1c, 0x43, 0x2b, 0x72, 0x0b, 0x19, 0xd1, 0x8e, 0xc8, 0xd8, 0x4b, 0xdc, 0x63, 0x15,
+        0x1b,
+    ],
+    [
+        0xf7, 0xe5, 0xae, 0xf5, 0x49, 0xf7, 0x82, 0xcf, 0x37, 0x90, 0x55, 0xa6, 0x08, 0x26, 0x9b,
+        0x16,
+    ],
+    [
+        0x43, 0x8d, 0x03, 0x0f, 0xd0, 0xb7, 0xa5, 0x4f, 0xa8, 0x37, 0xf2, 0xad, 0x20, 0x1a, 0x64,
+        0x03,
+    ],
+    [
+        0xa5, 0x90, 0xd3, 0xee, 0x4f, 0xbf, 0x04, 0xe3, 0x24, 0x7e, 0x0d, 0x27, 0xf2, 0x86, 0x42,
+        0x3f,
+    ],
+    [
+        0x5f, 0xe2, 0xc1, 0xa1, 0x72, 0xfe, 0x93, 0xc4, 0xb1, 0x5c, 0xd3, 0x7c, 0xae, 0xf9, 0xf5,
+        0x38,
+    ],
+    [
+        0x2c, 0x97, 0x32, 0x5c, 0xbd, 0x06, 0xb3, 0x6e, 0xb2, 0x13, 0x3d, 0xd0, 0x8b, 0x3a, 0x01,
+        0x7c,
+    ],
+    [
+        0x92, 0xc8, 0x14, 0x22, 0x7a, 0x6b, 0xca, 0x94, 0x9f, 0xf0, 0x65, 0x9f, 0x00, 0x2a, 0xd3,
+        0x9e,
+    ],
+    [
+        0xdc, 0xe8, 0x50, 0x11, 0x0b, 0xd8, 0x32, 0x8c, 0xfb, 0xd5, 0x08, 0x41, 0xd6, 0x91, 0x1d,
+        0x87,
+    ],
+    [
+        0x67, 0xf1, 0x49, 0x84, 0xc7, 0xda, 0x79, 0x12, 0x48, 0xe3, 0x2b, 0xb5, 0x92, 0x25, 0x83,
+        0xda,
+    ],
+    [
+        0x19, 0x38, 0xf2, 0xcf, 0x72, 0xd5, 0x4e, 0xe9, 0x7e, 0x94, 0x16, 0x6f, 0xa9, 0x1d, 0x2a,
+        0x36,
+    ],
+    [
+        0x74, 0x48, 0x1e, 0x96, 0x46, 0xed, 0x49, 0xfe, 0x0f, 0x62, 0x24, 0x30, 0x16, 0x04, 0x69,
+        0x8e,
+    ],
+    [
+        0x57, 0xfc, 0xa5, 0xde, 0x98, 0xa9, 0xd6, 0xd8, 0x00, 0x64, 0x38, 0xd0, 0x58, 0x3d, 0x8a,
+        0x1d,
+    ],
+    [
+        0x9f, 0xec, 0xde, 0x1c, 0xef, 0xdc, 0x1c, 0xbe, 0xd4, 0x76, 0x36, 0x74, 0xd9, 0x57, 0x53,
+        0x59,
+    ],
+    [
+        0xe3, 0x04, 0x0c, 0x00, 0xeb, 0x28, 0xf1, 0x53, 0x66, 0xca, 0x73, 0xcb, 0xd8, 0x72, 0xe7,
+        0x40,
+    ],
+    [
+        0x76, 0x97, 0x00, 0x9a, 0x6a, 0x83, 0x1d, 0xfe, 0xcc, 0xa9, 0x1c, 0x59, 0x93, 0x67, 0x0f,
+        0x7a,
+    ],
+    [
+        0x58, 0x53, 0x54, 0x23, 0x21, 0xf5, 0x67, 0xa0, 0x05, 0xd5, 0x47, 0xa4, 0xf0, 0x47, 0x59,
+        0xbd,
+    ],
+    [
+        0x51, 0x50, 0xd1, 0x77, 0x2f, 0x50, 0x83, 0x4a, 0x50, 0x3e, 0x06, 0x9a, 0x97, 0x3f, 0xbd,
+        0x7c,
+    ],
+];
+
+// Test vector from reference implementation
+#[test]
+fn test_siphash_2_4_test_vector() {
+    let k0 = 0x_07_06_05_04_03_02_01_00;
+    let k1 = 0x_0f_0e_0d_0c_0b_0a_09_08;
+
+    let mut input: Vec<u8> = Vec::new();
+
+    for i in 0..64 {
+        let out = hash_with(SipHasher128::new_with_keys(k0, k1), &Bytes(&input[..]));
+        let expected = (
+            ((TEST_VECTOR[i][0] as u64) << 0)
+                | ((TEST_VECTOR[i][1] as u64) << 8)
+                | ((TEST_VECTOR[i][2] as u64) << 16)
+                | ((TEST_VECTOR[i][3] as u64) << 24)
+                | ((TEST_VECTOR[i][4] as u64) << 32)
+                | ((TEST_VECTOR[i][5] as u64) << 40)
+                | ((TEST_VECTOR[i][6] as u64) << 48)
+                | ((TEST_VECTOR[i][7] as u64) << 56),
+            ((TEST_VECTOR[i][8] as u64) << 0)
+                | ((TEST_VECTOR[i][9] as u64) << 8)
+                | ((TEST_VECTOR[i][10] as u64) << 16)
+                | ((TEST_VECTOR[i][11] as u64) << 24)
+                | ((TEST_VECTOR[i][12] as u64) << 32)
+                | ((TEST_VECTOR[i][13] as u64) << 40)
+                | ((TEST_VECTOR[i][14] as u64) << 48)
+                | ((TEST_VECTOR[i][15] as u64) << 56),
+        );
+
+        assert_eq!(out, expected);
+        input.push(i as u8);
+    }
+}
+
+#[test]
+#[cfg(target_arch = "arm")]
+fn test_hash_usize() {
+    let val = 0xdeadbeef_deadbeef_u64;
+    assert!(hash(&(val as u64)) != hash(&(val as usize)));
+    assert_eq!(hash(&(val as u32)), hash(&(val as usize)));
+}
+#[test]
+#[cfg(target_arch = "x86_64")]
+fn test_hash_usize() {
+    let val = 0xdeadbeef_deadbeef_u64;
+    assert_eq!(hash(&(val as u64)), hash(&(val as usize)));
+    assert!(hash(&(val as u32)) != hash(&(val as usize)));
+}
+#[test]
+#[cfg(target_arch = "x86")]
+fn test_hash_usize() {
+    let val = 0xdeadbeef_deadbeef_u64;
+    assert!(hash(&(val as u64)) != hash(&(val as usize)));
+    assert_eq!(hash(&(val as u32)), hash(&(val as usize)));
+}
+
+#[test]
+fn test_hash_idempotent() {
+    let val64 = 0xdeadbeef_deadbeef_u64;
+    assert_eq!(hash(&val64), hash(&val64));
+    let val32 = 0xdeadbeef_u32;
+    assert_eq!(hash(&val32), hash(&val32));
+}
+
+#[test]
+fn test_hash_no_bytes_dropped_64() {
+    let val = 0xdeadbeef_deadbeef_u64;
+
+    assert!(hash(&val) != hash(&zero_byte(val, 0)));
+    assert!(hash(&val) != hash(&zero_byte(val, 1)));
+    assert!(hash(&val) != hash(&zero_byte(val, 2)));
+    assert!(hash(&val) != hash(&zero_byte(val, 3)));
+    assert!(hash(&val) != hash(&zero_byte(val, 4)));
+    assert!(hash(&val) != hash(&zero_byte(val, 5)));
+    assert!(hash(&val) != hash(&zero_byte(val, 6)));
+    assert!(hash(&val) != hash(&zero_byte(val, 7)));
+
+    fn zero_byte(val: u64, byte: usize) -> u64 {
+        assert!(byte < 8);
+        val & !(0xff << (byte * 8))
+    }
+}
+
+#[test]
+fn test_hash_no_bytes_dropped_32() {
+    let val = 0xdeadbeef_u32;
+
+    assert!(hash(&val) != hash(&zero_byte(val, 0)));
+    assert!(hash(&val) != hash(&zero_byte(val, 1)));
+    assert!(hash(&val) != hash(&zero_byte(val, 2)));
+    assert!(hash(&val) != hash(&zero_byte(val, 3)));
+
+    fn zero_byte(val: u32, byte: usize) -> u32 {
+        assert!(byte < 4);
+        val & !(0xff << (byte * 8))
+    }
+}
+
+#[test]
+fn test_hash_no_concat_alias() {
+    let s = ("aa", "bb");
+    let t = ("aabb", "");
+    let u = ("a", "abb");
+
+    assert!(s != t && t != u);
+    assert!(hash(&s) != hash(&t) && hash(&s) != hash(&u));
+
+    let u = [1, 0, 0, 0];
+    let v = (&u[..1], &u[1..3], &u[3..]);
+    let w = (&u[..], &u[4..4], &u[4..4]);
+
+    assert!(v != w);
+    assert!(hash(&v) != hash(&w));
+}
+
+#[test]
+fn test_short_write_works() {
+    let test_u8 = 0xFF_u8;
+    let test_u16 = 0x1122_u16;
+    let test_u32 = 0x22334455_u32;
+    let test_u64 = 0x33445566_778899AA_u64;
+    let test_u128 = 0x11223344_55667788_99AABBCC_DDEEFF77_u128;
+    let test_usize = 0xD0C0B0A0_usize;
+
+    let test_i8 = -1_i8;
+    let test_i16 = -2_i16;
+    let test_i32 = -3_i32;
+    let test_i64 = -4_i64;
+    let test_i128 = -5_i128;
+    let test_isize = -6_isize;
+
+    let mut h1 = SipHasher128::new_with_keys(0, 0);
+    h1.write(b"bytes");
+    h1.write(b"string");
+    h1.write_u8(test_u8);
+    h1.write_u16(test_u16);
+    h1.write_u32(test_u32);
+    h1.write_u64(test_u64);
+    h1.write_u128(test_u128);
+    h1.write_usize(test_usize);
+    h1.write_i8(test_i8);
+    h1.write_i16(test_i16);
+    h1.write_i32(test_i32);
+    h1.write_i64(test_i64);
+    h1.write_i128(test_i128);
+    h1.write_isize(test_isize);
+
+    let mut h2 = SipHasher128::new_with_keys(0, 0);
+    h2.write(b"bytes");
+    h2.write(b"string");
+    h2.write(&test_u8.to_ne_bytes());
+    h2.write(&test_u16.to_ne_bytes());
+    h2.write(&test_u32.to_ne_bytes());
+    h2.write(&test_u64.to_ne_bytes());
+    h2.write(&test_u128.to_ne_bytes());
+    h2.write(&test_usize.to_ne_bytes());
+    h2.write(&test_i8.to_ne_bytes());
+    h2.write(&test_i16.to_ne_bytes());
+    h2.write(&test_i32.to_ne_bytes());
+    h2.write(&test_i64.to_ne_bytes());
+    h2.write(&test_i128.to_ne_bytes());
+    h2.write(&test_isize.to_ne_bytes());
+
+    let h1_hash = h1.finish128();
+    let h2_hash = h2.finish128();
+
+    assert_eq!(h1_hash, h2_hash);
+}
+
+macro_rules! test_fill_buffer {
+    ($type:ty, $write_method:ident) => {{
+        // Test filling and overfilling the buffer from all possible offsets
+        // for a given integer type and its corresponding write method.
+        const SIZE: usize = std::mem::size_of::<$type>();
+        let input = [42; BUFFER_SIZE];
+        let x = 0x01234567_89ABCDEF_76543210_FEDCBA98_u128 as $type;
+        let x_bytes = &x.to_ne_bytes();
+
+        for i in 1..=SIZE {
+            let s = &input[..BUFFER_SIZE - i];
+
+            let mut h1 = SipHasher128::new_with_keys(7, 13);
+            h1.write(s);
+            h1.$write_method(x);
+
+            let mut h2 = SipHasher128::new_with_keys(7, 13);
+            h2.write(s);
+            h2.write(x_bytes);
+
+            let h1_hash = h1.finish128();
+            let h2_hash = h2.finish128();
+
+            assert_eq!(h1_hash, h2_hash);
+        }
+    }};
+}
+
+#[test]
+fn test_fill_buffer() {
+    test_fill_buffer!(u8, write_u8);
+    test_fill_buffer!(u16, write_u16);
+    test_fill_buffer!(u32, write_u32);
+    test_fill_buffer!(u64, write_u64);
+    test_fill_buffer!(u128, write_u128);
+    test_fill_buffer!(usize, write_usize);
+
+    test_fill_buffer!(i8, write_i8);
+    test_fill_buffer!(i16, write_i16);
+    test_fill_buffer!(i32, write_i32);
+    test_fill_buffer!(i64, write_i64);
+    test_fill_buffer!(i128, write_i128);
+    test_fill_buffer!(isize, write_isize);
+}