varint: store Bytes instead of Vec<u8>

Author: muzarski

scylla-cql/src/frame/value.rs

@@ -1,5 +1,5 @@
 use crate::frame::types;
-use bytes::BufMut;
+use bytes::{BufMut, Bytes};
 use std::borrow::Cow;
 use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
 use std::convert::TryInto;
@@ -231,32 +231,24 @@ impl std::hash::Hash for CqlTimeuuid {
 /// The implementation of [`PartialEq`], however, normalizes the underlying bytes
 /// before comparison. For details, check [examples](#impl-PartialEq-for-CqlVarint).
 #[derive(Clone, Eq, Debug)]
-pub struct CqlVarint(Vec<u8>);
+pub struct CqlVarint(Bytes);
 
 /// Constructors from bytes
 impl CqlVarint {
     /// Creates a [`CqlVarint`] from an array of bytes in
     /// two's complement big-endian binary representation.
     ///
     /// See: disclaimer about [non-normalized values](CqlVarint#db-data-format).
-    pub fn from_signed_bytes_be(digits: Vec<u8>) -> Self {
-        Self(digits)
-    }
-
-    /// Creates a [`CqlVarint`] from a slice of bytes in
-    /// two's complement binary big-endian representation.
-    ///
-    /// See: disclaimer about [non-normalized values](CqlVarint#db-data-format).
-    pub fn from_signed_bytes_be_slice(digits: &[u8]) -> Self {
-        Self::from_signed_bytes_be(digits.to_vec())
+    pub fn from_signed_bytes_be(digits: impl Into<Bytes>) -> Self {
+        Self(digits.into())
     }
 }
 
 /// Conversion to bytes
 impl CqlVarint {
     /// Converts [`CqlVarint`] to an array of bytes in two's
     /// complement binary big-endian representation.
-    pub fn into_signed_bytes_be(self) -> Vec<u8> {
+    pub fn into_signed_bytes_be(self) -> Bytes {
         self.0
     }
 
@@ -269,7 +261,7 @@ impl CqlVarint {
 
 impl CqlVarint {
     fn as_normalized_slice(&self) -> &[u8] {
-        let digits = self.0.as_slice();
+        let digits = self.as_signed_bytes_be_slice();
         if digits.is_empty() {
             // num-bigint crate normalizes empty vector to 0.
             // We will follow the same approach.
@@ -332,7 +324,7 @@ impl std::hash::Hash for CqlVarint {
 #[cfg(feature = "num-bigint-03")]
 impl From<num_bigint_03::BigInt> for CqlVarint {
     fn from(value: num_bigint_03::BigInt) -> Self {
-        Self(value.to_signed_bytes_be())
+        Self::from_signed_bytes_be(value.to_signed_bytes_be())
     }
 }
 
@@ -346,7 +338,7 @@ impl From<CqlVarint> for num_bigint_03::BigInt {
 #[cfg(feature = "num-bigint-04")]
 impl From<num_bigint_04::BigInt> for CqlVarint {
     fn from(value: num_bigint_04::BigInt) -> Self {
-        Self(value.to_signed_bytes_be())
+        Self::from_signed_bytes_be(value.to_signed_bytes_be())
     }
 }
 
@@ -411,7 +403,7 @@ impl CqlDecimal {
 
     /// Converts [`CqlDecimal`] to an array of bytes in two's
     /// complement binary big-endian representation and a scale.
-    pub fn into_signed_be_bytes_and_exponent(self) -> (Vec<u8>, i32) {
+    pub fn into_signed_be_bytes_and_exponent(self) -> (Bytes, i32) {
         (self.int_val.into_signed_bytes_be(), self.scale)
     }
 }

scylla-cql/src/frame/value_tests.rs

@@ -137,7 +137,7 @@ fn cql_varint_serialization() {
     ];
 
     for b in cases_from_the_spec {
-        let x = CqlVarint::from_signed_bytes_be_slice(b);
+        let x = CqlVarint::from_signed_bytes_be(bytes::Bytes::copy_from_slice(b));
         let b_with_len = (b.len() as i32)
             .to_be_bytes()
             .iter()

scylla-cql/src/types/deserialize/value.rs

@@ -217,8 +217,8 @@ impl_emptiable_strict_type!(
     CqlVarint,
     Varint,
     |typ: &'metadata ColumnType<'metadata>, v: Option<FrameSlice<'frame>>| {
-        let val = ensure_not_null_slice::<Self>(typ, v)?;
-        Ok(CqlVarint::from_signed_bytes_be_slice(val))
+        let val = ensure_not_null_owned::<Self>(typ, v)?;
+        Ok(CqlVarint::from_signed_bytes_be(val))
     }
 );
 

scylla-cql/src/types/deserialize/value_tests.rs

@@ -155,7 +155,7 @@ fn test_varlen_numbers() {
     // varint
     assert_ser_de_identity(
         &ColumnType::Varint,
-        &CqlVarint::from_signed_bytes_be_slice(b"Ala ma kota"),
+        &CqlVarint::from_signed_bytes_be(Bytes::from_static(b"Ala ma kota")),
         &mut Bytes::new(),
     );
 

scylla/tests/integration/cql_types.rs

@@ -200,7 +200,7 @@ async fn test_cql_varint() {
         .unwrap();
 
     for test in tests {
-        let cql_varint = CqlVarint::from_signed_bytes_be_slice(&test);
+        let cql_varint = CqlVarint::from_signed_bytes_be(test);
         session
             .execute_unpaged(&prepared_insert, (&cql_varint,))
             .await