add utils::BincodeVecWriter

lib/src/util.rs

@@ -1,14 +1,57 @@
-pub trait ErrorToString {
-    type Output;
-    fn str_err(self) -> std::result::Result<Self::Output, String>;
-}
-
-impl<T, E> ErrorToString for std::result::Result<T, E>
-where
-    E: std::error::Error,
-{
-    type Output = T;
-    fn str_err(self) -> std::result::Result<Self::Output, String> {
-        self.map_err(|e| e.to_string())
-    }
-}
+pub trait ErrorToString {
+    type Output;
+    fn str_err(self) -> std::result::Result<Self::Output, String>;
+}
+
+impl<T, E> ErrorToString for std::result::Result<T, E>
+where
+    E: std::error::Error,
+{
+    type Output = T;
+    fn str_err(self) -> std::result::Result<Self::Output, String> {
+        self.map_err(|e| e.to_string())
+    }
+}
+
+#[cfg(any(feature = "sync", feature = "async"))]
+mod bincode_utils {
+    use std::ops::{Deref, DerefMut};
+
+    use bincode::enc::write::Writer;
+    use bincode::error::EncodeError;
+
+    /// struct that allows [`Vec<u8>`] to implement [bincode::enc::write::Writer] trait
+    pub struct BincodeVecWriter {
+        vec: Vec<u8>,
+    }
+
+    impl BincodeVecWriter {
+        pub fn new(vec: Vec<u8>) -> BincodeVecWriter {
+            BincodeVecWriter { vec }
+        }
+    }
+
+    impl Deref for BincodeVecWriter {
+        type Target = Vec<u8>;
+
+        fn deref(&self) -> &Self::Target {
+            &self.vec
+        }
+    }
+
+    impl DerefMut for BincodeVecWriter {
+        fn deref_mut(&mut self) -> &mut Self::Target {
+            &mut self.vec
+        }
+    }
+
+    impl Writer for BincodeVecWriter {
+        fn write(&mut self, bytes: &[u8]) -> Result<(), EncodeError> {
+            self.vec.extend_from_slice(bytes);
+            Ok(())
+        }
+    }
+}
+
+#[cfg(any(feature = "sync", feature = "async"))]
+pub use bincode_utils::BincodeVecWriter;