Rollup merge of rust-lang#65686 - yjhmelody:yjhmelody-patch-1, r=Centril

refactor and move `maybe_append`

src/libsyntax/parse/parser.rs

@@ -86,13 +86,6 @@ macro_rules! maybe_recover_from_interpolated_ty_qpath {
     }
 }
 
-fn maybe_append(mut lhs: Vec<Attribute>, mut rhs: Option<Vec<Attribute>>) -> Vec<Attribute> {
-    if let Some(ref mut rhs) = rhs {
-        lhs.append(rhs);
-    }
-    lhs
-}
-
 #[derive(Debug, Clone, Copy, PartialEq)]
 enum PrevTokenKind {
     DocComment,

src/libsyntax/parse/parser/item.rs

@@ -10,7 +10,6 @@ use crate::ast::{Visibility, VisibilityKind, Mutability, FnHeader, ForeignItem,
 use crate::ast::{Ty, TyKind, Generics, GenericBounds, TraitRef, EnumDef, VariantData, StructField};
 use crate::ast::{Mac, MacDelimiter, Block, BindingMode, FnDecl, MethodSig, SelfKind, Param};
 use crate::parse::token;
-use crate::parse::parser::maybe_append;
 use crate::tokenstream::{TokenTree, TokenStream};
 use crate::symbol::{kw, sym};
 use crate::source_map::{self, respan, Span};
@@ -416,10 +415,17 @@ impl<'a> Parser<'a> {
     ) -> PResult<'a, Option<P<Item>>> {
         let (ident, item, extra_attrs) = info;
         let span = lo.to(self.prev_span);
-        let attrs = maybe_append(attrs, extra_attrs);
+        let attrs = Self::maybe_append(attrs, extra_attrs);
         Ok(Some(self.mk_item(span, ident, item, vis, attrs)))
     }
 
+    fn maybe_append<T>(mut lhs: Vec<T>, mut rhs: Option<Vec<T>>) -> Vec<T> {
+        if let Some(ref mut rhs) = rhs {
+            lhs.append(rhs);
+        }
+        lhs
+    }
+
     /// This is the fall-through for parsing items.
     fn parse_macro_use_or_failure(
         &mut self,