Merge pull request #2671 from dtolnay/deadremote

Fix new dead_code warning in tuple struct and tuple variant remote defs

serde_derive/src/pretend.rs

@@ -64,14 +64,14 @@ pub fn pretend_used(cont: &Container, is_packed: bool) -> TokenStream {
 fn pretend_fields_used(cont: &Container, is_packed: bool) -> TokenStream {
     match &cont.data {
         Data::Enum(variants) => pretend_fields_used_enum(cont, variants),
-        Data::Struct(Style::Struct, fields) => {
+        Data::Struct(Style::Struct | Style::Tuple | Style::Newtype, fields) => {
             if is_packed {
                 pretend_fields_used_struct_packed(cont, fields)
             } else {
                 pretend_fields_used_struct(cont, fields)
             }
         }
-        Data::Struct(_, _) => quote!(),
+        Data::Struct(Style::Unit, _) => quote!(),
     }
 }
 
@@ -115,13 +115,13 @@ fn pretend_fields_used_enum(cont: &Container, variants: &[Variant]) -> TokenStre
     let patterns = variants
         .iter()
         .filter_map(|variant| match variant.style {
-            Style::Struct => {
+            Style::Struct | Style::Tuple | Style::Newtype => {
                 let variant_ident = &variant.ident;
                 let members = variant.fields.iter().map(|field| &field.member);
                 let placeholders = (0usize..).map(|i| format_ident!("__v{}", i));
                 Some(quote!(#type_ident::#variant_ident { #(#members: #placeholders),* }))
             }
-            _ => None,
+            Style::Unit => None,
         })
         .collect::<Vec<_>>();