Add specific message for tuple struct invoked with suffixed numeric field name

Author: estebank

src/libsyntax/parse/parser.rs

@@ -2491,7 +2491,8 @@ impl<'a> Parser<'a> {
     }
 
     fn parse_field_name(&mut self) -> PResult<'a, Ident> {
-        if let token::Literal(token::Integer(name), None) = self.token {
+        if let token::Literal(token::Integer(name), suffix) = self.token {
+            self.expect_no_suffix(self.span, "a tuple index", suffix);
             self.bump();
             Ok(Ident::new(name, self.prev_span))
         } else {

src/test/ui/parser/issue-59418.rs

@@ -9,4 +9,10 @@ fn main() {
     let d = c.1suffix;
     //~^ ERROR suffixes on a tuple index are invalid
     println!("{}", d);
+    let s = X { 0suffix: 0, 1: 1, 2: 2 };
+    //~^ ERROR suffixes on a tuple index are invalid
+    match s {
+        X { 0suffix: _, .. } => {}
+        //~^ ERROR suffixes on a tuple index are invalid
+    }
 }

src/test/ui/parser/issue-59418.stderr

@@ -10,5 +10,17 @@ error: suffixes on a tuple index are invalid
 LL |     let d = c.1suffix;
    |               ^^^^^^^ invalid suffix `suffix`
 
-error: aborting due to 2 previous errors
+error: suffixes on a tuple index are invalid
+  --> $DIR/issue-59418.rs:12:17
+   |
+LL |     let s = X { 0suffix: 0, 1: 1, 2: 2 };
+   |                 ^^^^^^^ invalid suffix `suffix`
+
+error: suffixes on a tuple index are invalid
+  --> $DIR/issue-59418.rs:15:13
+   |
+LL |         X { 0suffix: _, .. } => {}
+   |             ^^^^^^^ invalid suffix `suffix`
+
+error: aborting due to 4 previous errors