Detect actual span for getting unexpected token from parsing macros

Author: chenyukang

compiler/rustc_parse/src/parser/expr.rs

@@ -1013,9 +1013,15 @@ impl<'a> Parser<'a> {
     }
 
     fn error_unexpected_after_dot(&self) {
-        // FIXME Could factor this out into non_fatal_unexpected or something.
         let actual = pprust::token_to_string(&self.token);
-        self.sess.emit_err(errors::UnexpectedTokenAfterDot { span: self.token.span, actual });
+        let span = self.token.span;
+        let sm = self.sess.source_map();
+        let (span, actual) = match (&self.token.kind, self.subparser_name) {
+            (token::Eof, Some(_)) if let Ok(actual) = sm.span_to_snippet(sm.next_point(span)) =>
+                (span.shrink_to_hi(), actual.into()),
+            _ => (span, actual),
+        };
+        self.sess.emit_err(errors::UnexpectedTokenAfterDot { span, actual });
     }
 
     // We need an identifier or integer, but the next token is a float.

tests/ui/parser/issues/issue-112458.rs

@@ -0,0 +1,4 @@
+fn main() {
+    println!("{}", x.); //~ ERROR unexpected token: `)`
+    //~^ ERROR cannot find value `x` in this scope
+}

tests/ui/parser/issues/issue-112458.stderr

@@ -0,0 +1,15 @@
+error: unexpected token: `)`
+  --> $DIR/issue-112458.rs:2:22
+   |
+LL |     println!("{}", x.);
+   |                      ^
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-112458.rs:2:20
+   |
+LL |     println!("{}", x.);
+   |                    ^ not found in this scope
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0425`.