contracts: port from syn v1 to syn v2

vendored/contracts/Cargo.toml

@@ -35,6 +35,6 @@ override_log = []
 mirai_assertions = []
 
 [dependencies]
-syn = { version = "1.0", features = ["extra-traits", "full", "visit", "visit-mut"] }
+syn = { version = "2.0", features = ["extra-traits", "full", "visit", "visit-mut"] }
 quote = "1.0"
 proc-macro2 = "1.0"

vendored/contracts/src/implementation/codegen.rs

@@ -6,7 +6,7 @@ use proc_macro2::{Ident, Span, TokenStream};
 use quote::ToTokens;
 use syn::{
     spanned::Spanned, visit_mut as visitor, Attribute, Expr, ExprCall, ExprTry,
-    ReturnType, Type, TypeImplTrait,
+    ReturnType, TypeImplTrait,
 };
 
 use crate::implementation::{

vendored/contracts/src/implementation/invariant.rs

@@ -4,7 +4,7 @@
 
 use proc_macro2::TokenStream;
 use quote::ToTokens;
-use syn::{FnArg, ImplItem, ImplItemMethod, Item, ItemFn, ItemImpl};
+use syn::{FnArg, ImplItem, ImplItemFn, Item, ItemFn, ItemImpl};
 
 use crate::implementation::{ContractMode, ContractType, FuncWithContracts};
 
@@ -62,7 +62,7 @@ fn invariant_impl(
     let invariant_ident =
         syn::Ident::new(&name, proc_macro2::Span::call_site());
 
-    fn method_uses_self(method: &ImplItemMethod) -> bool {
+    fn method_uses_self(method: &ImplItemFn) -> bool {
         let inputs = &method.sig.inputs;
 
         if !inputs.is_empty() {
@@ -73,7 +73,7 @@ fn invariant_impl(
     }
 
     for item in &mut impl_def.items {
-        if let ImplItem::Method(method) = item {
+        if let ImplItem::Fn(method) = item {
             // only implement invariants for methods that take `self`
             if !method_uses_self(method) {
                 continue;
@@ -84,7 +84,7 @@ fn invariant_impl(
                 #method
             };
 
-            let met: ImplItemMethod = syn::parse_quote!(#method_toks);
+            let met: ImplItemFn = syn::parse_quote!(#method_toks);
 
             *method = met;
         }

vendored/contracts/src/implementation/mod.rs

@@ -15,7 +15,7 @@ use syn::{Expr, ItemFn};
 
 pub(crate) use ensures::ensures;
 pub(crate) use invariant::invariant;
-use proc_macro2::{Span, TokenStream, TokenTree};
+use proc_macro2::{Span, TokenStream};
 pub(crate) use requires::requires;
 pub(crate) use traits::{contract_trait_item_impl, contract_trait_item_trait};
 
@@ -185,7 +185,7 @@ impl FuncWithContracts {
             .attrs
             .iter()
             .filter_map(|a| {
-                let name = a.path.segments.last().unwrap().ident.to_string();
+                let name = a.path().segments.last().unwrap().ident.to_string();
                 let (ty, mode) = ContractType::contract_type_and_mode(&name)?;
                 Some((ty, mode, a))
             })
@@ -194,15 +194,12 @@ impl FuncWithContracts {
                 // code might be mistakenly parsed as tuples, that's not good!
                 //
                 // this is a hack to get to the inner token stream.
-
+                use syn::Meta;
-                let tok_tree = a.tokens.clone().into_iter().next().unwrap();
+                let toks = match &a.meta {
-                let toks = match tok_tree {
+                    Meta::Path(_) => unreachable!(),
-                    TokenTree::Group(group) => group.stream(),
+                    Meta::List(x) => x.tokens.clone(),
-                    TokenTree::Ident(i) => i.into_token_stream(),
+                    Meta::NameValue(x) => x.value.to_token_stream(),
-                    TokenTree::Punct(p) => p.into_token_stream(),
-                    TokenTree::Literal(l) => l.into_token_stream(),
                 };
-
                 Contract::from_toks(ty, mode, toks)
             });
 
@@ -216,7 +213,7 @@ impl FuncWithContracts {
                 .into_iter()
                 .filter(|attr| {
                     ContractType::contract_type_and_mode(
-                        &attr.path.segments.last().unwrap().ident.to_string(),
+                        &attr.path().segments.last().unwrap().ident.to_string(),
                     )
                     .is_none()
                 })

vendored/contracts/src/implementation/traits.rs

@@ -6,7 +6,7 @@ use crate::implementation::ContractType;
 use proc_macro2::TokenStream;
 use quote::ToTokens;
 use syn::{
-    FnArg, ImplItem, ItemImpl, ItemTrait, Pat, TraitItem, TraitItemMethod,
+    FnArg, ImplItem, ItemImpl, ItemTrait, Pat, TraitItem, TraitItemFn,
 };
 
 /// Name used for the "re-routed" method.
@@ -20,8 +20,8 @@ pub(crate) fn contract_trait_item_trait(
     mut trait_: ItemTrait,
 ) -> TokenStream {
     /// Just rename the method to have an internal, generated name.
-    fn create_method_rename(method: &TraitItemMethod) -> TraitItemMethod {
+    fn create_method_rename(method: &TraitItemFn) -> TraitItemFn {
-        let mut m: TraitItemMethod = (*method).clone();
+        let mut m: TraitItemFn = (*method).clone();
 
         // rename method and modify attributes
         {
@@ -41,7 +41,7 @@ pub(crate) fn contract_trait_item_trait(
                     .iter()
                     .filter(|a| {
                         let name =
-                            a.path.segments.last().unwrap().ident.to_string();
+                            a.path().segments.last().unwrap().ident.to_string();
 
                         ContractType::contract_type_and_mode(&name).is_none()
                     })
@@ -60,7 +60,7 @@ pub(crate) fn contract_trait_item_trait(
     /// includes contracts.
     ///
     /// This new function forwards the call to the actual implementation.
-    fn create_method_wrapper(method: &TraitItemMethod) -> TraitItemMethod {
+    fn create_method_wrapper(method: &TraitItemFn) -> TraitItemFn {
         struct ArgInfo {
             call_toks: proc_macro2::TokenStream,
         }
@@ -97,7 +97,7 @@ pub(crate) fn contract_trait_item_trait(
             }
         }
 
-        let mut m: TraitItemMethod = (*method).clone();
+        let mut m: TraitItemFn = (*method).clone();
 
         let argument_data = m
             .sig
@@ -144,7 +144,7 @@ pub(crate) fn contract_trait_item_trait(
                 .iter()
                 .filter(|a| {
                     let name =
-                        a.path.segments.last().unwrap().ident.to_string();
+                        a.path().segments.last().unwrap().ident.to_string();
                     // is doc?
                     if name == "doc" {
                         return true;
@@ -174,13 +174,13 @@ pub(crate) fn contract_trait_item_trait(
         .items
         .iter()
         .filter_map(|item| {
-            if let TraitItem::Method(m) = item {
+            if let TraitItem::Fn(m) = item {
                 let rename = create_method_rename(m);
                 let wrapper = create_method_wrapper(m);
 
                 Some(vec![
-                    TraitItem::Method(rename),
+                    TraitItem::Fn(rename),
-                    TraitItem::Method(wrapper),
+                    TraitItem::Fn(wrapper),
                 ])
             } else {
                 None
@@ -193,7 +193,7 @@ pub(crate) fn contract_trait_item_trait(
     trait_.items = trait_
         .items
         .into_iter()
-        .filter(|item| !matches!(item, TraitItem::Method(_)))
+        .filter(|item| !matches!(item, TraitItem::Fn(_)))
         .collect();
 
     // add back new methods
@@ -212,7 +212,7 @@ pub(crate) fn contract_trait_item_impl(
         let mut impl_: ItemImpl = impl_;
 
         impl_.items.iter_mut().for_each(|it| {
-            if let ImplItem::Method(method) = it {
+            if let ImplItem::Fn(method) = it {
                 let new_name =
                     contract_method_impl_name(&method.sig.ident.to_string());
                 let new_ident =