Propagate the span of Self keyword to QSelf

src/receiver.rs

@@ -1,12 +1,12 @@
 use crate::respan::respan;
 use proc_macro2::{Group, Spacing, Span, TokenStream, TokenTree};
-use quote::quote;
+use quote::{quote, quote_spanned};
 use std::iter::FromIterator;
 use std::mem;
 use syn::punctuated::Punctuated;
 use syn::visit_mut::{self, VisitMut};
 use syn::{
-    parse_quote, Block, Error, ExprPath, ExprStruct, Ident, Item, Macro, PatPath, PatStruct,
+    parse_quote, token, Block, Error, ExprPath, ExprStruct, Ident, Item, Macro, PatPath, PatStruct,
     PatTupleStruct, Path, PathArguments, QSelf, Receiver, Signature, Type, TypePath,
     WherePredicate,
 };
@@ -105,12 +105,13 @@ impl ReplaceReceiver {
             return;
         }
 
+        let span = first.ident.span();
         *qself = Some(QSelf {
-            lt_token: Default::default(),
-            ty: Box::new(self.self_ty(first.ident.span())),
+            lt_token: token::Lt(span),
+            ty: Box::new(self.self_ty(span)),
             position: 0,
             as_token: None,
-            gt_token: Default::default(),
+            gt_token: token::Gt(span),
         });
 
         if include_as_trait && self.as_trait.is_some() {
@@ -182,7 +183,8 @@ impl ReplaceReceiver {
                                     let next = iter.next().unwrap();
                                     match iter.peek() {
                                         Some(TokenTree::Punct(p)) if p.as_char() == ':' => {
-                                            out.extend(quote!(<#self_ty>))
+                                            let span = ident.span();
+                                            out.extend(quote_spanned!(span=> <#self_ty>));
                                         }
                                         _ => out.extend(quote!(#self_ty)),
                                     }

tests/ui/self-span.rs

@@ -2,6 +2,10 @@ use async_trait::async_trait;
 
 pub struct S {}
 
+pub enum E {
+    V {}
+}
+
 #[async_trait]
 pub trait Trait {
     async fn method(self);
@@ -15,4 +19,12 @@ impl Trait for S {
     }
 }
 
+#[async_trait]
+impl Trait for E {
+    async fn method(self) {
+        let _: () = self;
+        let _: Self = Self::V;
+    }
+}
+
 fn main() {}

tests/ui/self-span.stderr

@@ -1,16 +1,30 @@
 error[E0423]: expected value, found struct `S`
-  --> $DIR/self-span.rs:14:23
+  --> $DIR/self-span.rs:18:23
    |
 3  | pub struct S {}
    | --------------- `S` defined here
 ...
-14 |         let _: Self = Self;
+18 |         let _: Self = Self;
    |                       ^^^^ did you mean `S { /* fields */ }`?
 
 error[E0308]: mismatched types
-  --> $DIR/self-span.rs:13:21
+  --> $DIR/self-span.rs:17:21
    |
-13 |         let _: () = self;
+17 |         let _: () = self;
    |                --   ^^^^ expected `()`, found struct `S`
    |                |
    |                expected due to this
+
+error[E0308]: mismatched types
+  --> $DIR/self-span.rs:25:21
+   |
+25 |         let _: () = self;
+   |                --   ^^^^ expected `()`, found enum `E`
+   |                |
+   |                expected due to this
+
+error[E0533]: expected unit struct, unit variant or constant, found struct variant `Self::V`
+  --> $DIR/self-span.rs:26:23
+   |
+26 |         let _: Self = Self::V;
+   |                       ^^^^^^^