Fix no_std issues

Author: sgued

src/bytearray.rs

@@ -9,6 +9,8 @@ use core::ops::{Deref, DerefMut};
 use serde::de::{Deserialize, Deserializer, Error, SeqAccess, Visitor};
 use serde::ser::{Serialize, Serializer};
 
+const ERROR_STRING: &'static str = "Expected a fixed amount of bytes, got a different amount";
+
 /// Wrapper around `[u8; N]` to serialize and deserialize efficiently.
 ///
 /// ```
@@ -189,21 +191,15 @@ impl<'de, const N: usize> Visitor<'de> for ByteArrayVisitor<N> {
         let mut idx = 0;
         while let Some(b) = visitor.next_element()? {
             if idx >= N {
-                return Err(V::Error::custom(format!(
-                    "Expected [u8; {0}], got more than {0} elements",
-                    N
-                )));
+                return Err(V::Error::custom(ERROR_STRING));
             }
 
             bytes[idx] = b;
             idx += 1;
         }
 
         if idx != N {
-            return Err(V::Error::custom(format!(
-                "Expected [u8; {}], got [u8; {}]",
-                N, idx
-            )));
+            return Err(V::Error::custom(ERROR_STRING));
         }
 
         Ok(ByteArray::from(bytes))
@@ -214,20 +210,7 @@ impl<'de, const N: usize> Visitor<'de> for ByteArrayVisitor<N> {
         E: Error,
     {
         Ok(ByteArray {
-            bytes: v
-                .try_into()
-                .map_err(|_| E::custom(format!("Expected [u8; {}]", N)))?,
-        })
-    }
-
-    fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<ByteArray<N>, E>
-    where
-        E: Error,
-    {
-        Ok(ByteArray {
-            bytes: v
-                .try_into()
-                .map_err(|_| E::custom(format!("Expected [u8; {}]", N)))?,
+            bytes: v.try_into().map_err(|_| E::custom(ERROR_STRING))?,
         })
     }
 
@@ -239,19 +222,7 @@ impl<'de, const N: usize> Visitor<'de> for ByteArrayVisitor<N> {
             bytes: v
                 .as_bytes()
                 .try_into()
-                .map_err(|_| E::custom(format!("Expected [u8; {}]", N)))?,
-        })
-    }
-
-    fn visit_string<E>(self, v: String) -> Result<ByteArray<N>, E>
-    where
-        E: Error,
-    {
-        Ok(ByteArray {
-            bytes: v
-                .as_bytes()
-                .try_into()
-                .map_err(|_| E::custom(format!("Expected [u8; {}]", N)))?,
+                .map_err(|_| E::custom(ERROR_STRING))?,
         })
     }
 }