fix failing compilation when deny_unknown_fields is set

simdnbt-derive/src/lib.rs

@@ -55,7 +55,7 @@ pub fn deserialize_derive(input: proc_macro::TokenStream) -> proc_macro::TokenSt
     let extra_checks = if struct_attrs.deny_unknown_fields {
         quote! {
             if !nbt.is_empty() {
-                return Err(simdnbt::DeserializeError::UnknownField(nbt.keys().next().unwrap().clone()));
+                return Err(simdnbt::DeserializeError::UnknownField(nbt.keys().next().unwrap().to_string()));
             }
         }
     } else {

simdnbt/examples/registry.rs

@@ -0,0 +1,35 @@
+use std::{collections::HashMap, io::Cursor};
+
+use simdnbt::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+#[simdnbt(deny_unknown_fields)]
+pub struct TrimMaterialElement {
+    pub asset_name: String,
+    pub item_model_index: f32,
+    pub override_armor_materials: HashMap<String, String>,
+    pub description: Option<String>,
+}
+
+fn main() {
+    let original = TrimMaterialElement {
+        asset_name: "asset name".to_string(),
+        item_model_index: 0.0,
+        override_armor_materials: HashMap::from_iter(vec![
+            ("asdf".into(), "fdsa".into()),
+            ("dsfgdgh".into(), "fgjrtiu".into()),
+        ]),
+        description: Some("description".to_string()),
+    };
+
+    let nbt = original.clone().to_nbt();
+    let mut buf = Vec::new();
+    nbt.write(&mut buf);
+
+    let nbt = simdnbt::borrow::read(&mut Cursor::new(&buf[..]))
+        .unwrap()
+        .unwrap();
+    let rewritten = TrimMaterialElement::from_nbt(&nbt).unwrap();
+
+    assert_eq!(original, rewritten);
+}

simdnbt/src/error.rs

@@ -20,6 +20,6 @@ pub enum DeserializeError {
     MissingField,
     #[error("Mismatched type for {0}")]
     MismatchedFieldType(String),
-    #[error("Unknown fields {0:?}")]
-    UnknownField(Vec<String>),
+    #[error("Unknown field {0:?}")]
+    UnknownField(String),
 }