Update to syn 2 (#2730)

Author: maurer

futures-macro/Cargo.toml

@@ -18,4 +18,4 @@ proc-macro = true
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = { version = "1.0.56", features = ["full"] }
+syn = { version = "2.0.8", features = ["full"] }

futures-macro/src/executor.rs

@@ -44,6 +44,7 @@ pub(crate) fn test(args: TokenStream, item: TokenStream) -> TokenStream {
             #path::block_on(async #body)
         })
         .unwrap(),
+        None,
     )];
 
     let gen = quote! {

futures-macro/src/select.rs

@@ -51,7 +51,7 @@ impl Parse for Select {
                 CaseKind::Default
             } else {
                 // `<pat> = <expr>`
-                let pat = input.parse()?;
+                let pat = Pat::parse_multi_with_leading_vert(input)?;
                 input.parse::<Token![=]>()?;
                 let expr = input.parse()?;
                 CaseKind::Normal(pat, expr)