dav: Refactor proppatch, remove InvalidProperty trait

crates/xml/derive/src/xml_struct.rs

@@ -5,11 +5,13 @@ use darling::FromDeriveInput;
 use quote::quote;
 use syn::{DataStruct, DeriveInput};
 
-fn invalid_field_branch(allow: bool) -> proc_macro2::TokenStream {
+fn invalid_field_branch(ident: &syn::Ident, allow: bool) -> proc_macro2::TokenStream {
+    let ident = ident.to_string();
     if allow {
         quote! {}
     } else {
-        quote! { return Err(XmlDeError::InvalidFieldName(format!("[{ns:?}]{tag}", tag = String::from_utf8_lossy(tag)))) }
+        quote! {
+        return Err(XmlDeError::InvalidFieldName(#ident, format!("[{ns:?}]{tag}", tag = String::from_utf8_lossy(tag)))) }
     }
 }
 
@@ -85,7 +87,8 @@ impl NamedStruct {
 
         let builder_field_builds = self.fields.iter().map(Field::builder_field_build);
 
-        let invalid_field_branch = invalid_field_branch(self.attrs.allow_invalid.is_present());
+        let invalid_field_branch =
+            invalid_field_branch(ident, self.attrs.allow_invalid.is_present());
 
         quote! {
             impl #impl_generics ::rustical_xml::XmlDeserialize for #ident #type_generics #where_clause {

crates/xml/src/de.rs

@@ -28,8 +28,8 @@ pub enum XmlDeError {
     Other(String),
     #[error("Invalid variant: {0}")]
     InvalidVariant(String),
-    #[error("Invalid field name: {0}")]
-    InvalidFieldName(String),
+    #[error("Invalid field name in {0}: {1}")]
+    InvalidFieldName(&'static str, String),
     #[error(transparent)]
     InvalidValue(#[from] crate::value::ParseValueError),
 }

crates/xml/src/lib.rs

@@ -36,6 +36,13 @@ impl XmlDeserialize for () {
 #[derive(Debug, Clone, PartialEq)]
 pub struct Unparsed(BytesStart<'static>);
 
+impl Unparsed {
+    pub fn tag_name(&self) -> String {
+        // TODO: respect namespace?
+        String::from_utf8_lossy(self.0.local_name().as_ref()).to_string()
+    }
+}
+
 impl XmlDeserialize for Unparsed {
     fn deserialize<R: BufRead>(
         reader: &mut quick_xml::NsReader<R>,