Make most of prepare_enum_variant_enum independent of variant_names_i…

…dents item type

serde_derive/src/de.rs

@@ -1225,33 +1225,33 @@ fn deserialize_homogeneous_enum(
 }
 
 fn prepare_enum_variant_enum(variants: &[Variant]) -> (TokenStream, Stmts) {
- let mut deserialized_variants = variants
+ let deserialized_variants = variants
  .iter()
  .enumerate()
- .filter(|&(_, variant)| !variant.attrs.skip_deserializing());
-
- let variant_names_idents: Vec<_> = deserialized_variants
- .clone()
- .map(|(i, variant)| (field_i(i), variant.attrs.aliases()))
- .collect();
+ .filter(|&(_i, variant)| !variant.attrs.skip_deserializing());
 
  let fallthrough = deserialized_variants
- .position(|(_, variant)| variant.attrs.other())
- .map(|other_idx| {
- let ignore_variant = variant_names_idents[other_idx].0.clone();
+ .clone()
+ .find(|(_i, variant)| variant.attrs.other())
+ .map(|(i, _variant)| {
+ let ignore_variant = field_i(i);
  quote!(_serde::__private::Ok(__Field::#ignore_variant))
  });
 
  let variants_stmt = {
- let variant_names = variant_names_idents
- .iter()
- .flat_map(|&(_, aliases)| aliases);
+ let variant_names = deserialized_variants
+ .clone()
+ .flat_map(|(_i, variant)| variant.attrs.aliases());
  quote! {
  #[doc(hidden)]
  const VARIANTS: &'static [&'static str] = &[ #(#variant_names),* ];
  }
  };
 
+ let variant_names_idents: Vec<_> = deserialized_variants
+ .map(|(i, variant)| (field_i(i), variant.attrs.aliases()))
+ .collect();
+
  let variant_visitor = Stmts(deserialize_generated_identifier(
  &variant_names_idents,
  false, // variant identifiers do not depend on the presence of flatten fields