From acc3811158c8042b41405e152cac980516d361db Mon Sep 17 00:00:00 2001
From: Thomas BESSOU <thomas.bessou@hotmail.fr>
Date: Mon, 11 Dec 2023 11:44:06 +0100
Subject: [PATCH] Add support for syn 2.0.40's new Expr::Group to
 dsl::auto_type

This expression may get yielded when parsing `$a: expr` from other macros.
---
 dsl_auto_type/src/auto_type/expression_type_inference.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/dsl_auto_type/src/auto_type/expression_type_inference.rs b/dsl_auto_type/src/auto_type/expression_type_inference.rs
index 5e84406ea13d..c42774ed2ef1 100644
--- a/dsl_auto_type/src/auto_type/expression_type_inference.rs
+++ b/dsl_auto_type/src/auto_type/expression_type_inference.rs
@@ -82,6 +82,9 @@ impl TypeInferrer<'_> {
             expr,
             type_hint.filter(|h| !matches!(h, syn::Type::Infer(_))),
         ) {
+            (syn::Expr::Group(syn::ExprGroup { expr, .. }), type_hint) => {
+                return self.try_infer_expression_type(expr, type_hint)
+            }
             (
                 syn::Expr::Tuple(syn::ExprTuple {
                     elems: expr_elems, ..
@@ -236,10 +239,10 @@ impl TypeInferrer<'_> {
                     ))
                 }
             },
-            (_, None) => {
+            (e, None) => {
                 return Err(syn::Error::new(
                     expr.span(),
-                    "unsupported expression for auto_type",
+                    format_args!("unsupported expression for auto_type: {e:?}"),
                 ))
             }
             (_, Some(type_hint)) => type_hint.clone(),