xml: EnumVariant variant_names for untagged enums

crates/xml/derive/src/xml_enum.rs

@@ -198,6 +198,23 @@ impl Enum {
         let (impl_generics, type_generics, where_clause) = self.generics.split_for_impl();
         let ident = &self.ident;
 
+        if self.attrs.untagged.is_present() {
+            let untagged_variants = self.variants.iter().map(|variant| {
+                let ty = &variant.deserializer_type();
+                quote! { #ty::variant_names() }
+            });
+            quote! {
+                impl #impl_generics ::rustical_xml::EnumVariants for #ident #type_generics #where_clause {
+                    const TAGGED_VARIANTS: &'static [(Option<::quick_xml::name::Namespace<'static>>, &'static str)] = &[];
+
+                    fn variant_names() -> Vec<(Option<Namespace<'static>>, &'static str)> {
+                        [
+                            #(#untagged_variants),*
+                        ].concat()
+                    }
+                }
+            }
+        } else {
             let tagged_variants = self.variants.iter().map(|variant| {
                 let ns = match &variant.attrs.common.ns {
                     Some(ns) => quote! { Some(#ns) },
@@ -213,6 +230,11 @@ impl Enum {
                     const TAGGED_VARIANTS: &'static [(Option<::quick_xml::name::Namespace<'static>>, &'static str)] = &[
                         #(#tagged_variants),*
                     ];
+
+                    fn variant_names() -> Vec<(Option<Namespace<'static>>, &'static str)> {
+                        [Self::TAGGED_VARIANTS,].concat()
+                    }
+                }
             }
         }
     }

crates/xml/derive/src/xml_struct.rs

@@ -259,7 +259,7 @@ impl NamedStruct {
             .map(|field| {
                 let field_index = field.target_field_index();
                 quote! {
-                    let ns = Some(self.#field_index);
+                    let ns = self.#field_index;
                 }
             });
 

crates/xml/src/lib.rs

@@ -25,4 +25,7 @@ pub trait XmlRootTag {
 
 pub trait EnumVariants {
     const TAGGED_VARIANTS: &'static [(Option<Namespace<'static>>, &'static str)];
+
+    // Returns all valid xml names including untagged variants
+    fn variant_names() -> Vec<(Option<Namespace<'static>>, &'static str)>;
 }

crates/xml/tests/enum_variants.rs

@@ -10,7 +10,12 @@ pub const NS_CALENDARSERVER: Namespace = Namespace(b"http://calendarserver.org/n
 pub const NS_NEXTCLOUD: Namespace = Namespace(b"http://nextcloud.com/ns");
 
 #[derive(EnumVariants)]
-pub enum CalendarProp {
+enum ExtensionProp {
+    Hello,
+}
+
+#[derive(EnumVariants)]
+enum CalendarProp {
     // WebDAV (RFC 2518)
     #[xml(ns = "NS_DAV")]
     Displayname(Option<String>),
@@ -23,7 +28,7 @@ pub enum CalendarProp {
 }
 
 #[test]
-fn test_enum_variants() {
+fn test_enum_tagged_variants() {
     assert_eq!(
         CalendarProp::TAGGED_VARIANTS,
         &[
@@ -34,3 +39,24 @@ fn test_enum_variants() {
         ]
     );
 }
+
+#[derive(EnumVariants)]
+#[xml(untagged)]
+enum UnionProp {
+    Calendar(CalendarProp),
+    Extension(ExtensionProp),
+}
+
+#[test]
+fn test_enum_untagged_variants() {
+    assert_eq!(
+        UnionProp::variant_names(),
+        vec![
+            (Some(NS_DAV), "displayname"),
+            (Some(NS_DAV), "getcontenttype"),
+            (Some(NS_DAV), "principal-URL"),
+            (None, "topic"),
+            (None, "hello"),
+        ]
+    );
+}