dav: Refactor proppatch, remove InvalidProperty trait

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>,