fix(rust): use iter to avoid reallocate

rust/fury-core/src/resolver/meta_resolver.rs

@@ -69,7 +69,7 @@ impl<'a> MetaWriterResolver<'a> {
 
     pub fn to_bytes(&self, writer: &mut Writer) -> Result<(), Error> {
         writer.var_int32(self.type_defs.len() as i32);
-        for item in self.type_defs.iter() {
+        for item in &self.type_defs {
             writer.bytes(item)
         }
         Ok(())

rust/fury-core/src/serializer/list.rs

@@ -38,14 +38,11 @@ where
     }
 
     fn read(context: &mut ReadContext) -> Result<Self, Error> {
-        // length
+        // vec length
         let len = context.reader.var_int32();
-        // value
-        let mut result = Vec::new();
-        for _ in 0..len {
-            result.push(T::deserialize(context)?);
-        }
-        Ok(result)
+        (0..len)
+            .map(|_| T::deserialize(context))
+            .collect::<Result<Vec<_>, Error>>()
     }
 
     fn reserved_space() -> usize {

rust/fury-core/src/serializer/map.rs

@@ -42,17 +42,14 @@ impl<T1: Serializer + Eq + std::hash::Hash, T2: Serializer> Serializer for HashM
     }
 
     fn read(context: &mut ReadContext) -> Result<Self, Error> {
-        // length
+        // map length
         let len = context.reader.var_int32();
-        let mut result = HashMap::new();
-        // key-value
-        for _ in 0..len {
-            result.insert(
-                <T1 as Serializer>::deserialize(context)?,
-                <T2 as Serializer>::deserialize(context)?,
-            );
-        }
-        Ok(result)
+        (0..len)
+            .map(|_| {
+                <T1 as Serializer>::deserialize(context)
+                    .and_then(|k| <T2 as Serializer>::deserialize(context).map(|v| (k, v)))
+            })
+            .collect::<Result<HashMap<_, _>, Error>>()
     }
 
     fn reserved_space() -> usize {

rust/fury-core/src/serializer/mod.rs

@@ -67,8 +67,8 @@ pub trait Serializer
 where
     Self: Sized,
 {
-    /// The fixed memory size of the Type.
-    /// Avoid the memory check, which would hurt performance.
+    /// The possible max memory size of the type.
+    /// Used to reserve the buffer space to avoid reallocation, which may hurt performance.
     fn reserved_space() -> usize;
 
     /// Write the data into the buffer.

rust/fury-core/src/serializer/set.rs

@@ -42,12 +42,9 @@ impl<T: Serializer + Eq + std::hash::Hash> Serializer for HashSet<T> {
     fn read(context: &mut ReadContext) -> Result<Self, Error> {
         // length
         let len = context.reader.var_int32();
-        let mut result = HashSet::new();
-        // key-value
-        for _ in 0..len {
-            result.insert(<T as Serializer>::deserialize(context)?);
-        }
-        Ok(result)
+        (0..len)
+            .map(|_| T::deserialize(context))
+            .collect::<Result<HashSet<_>, Error>>()
     }
 
     fn reserved_space() -> usize {