fix: use syn::Index for tuple access (#515)

* fix: use syn::Index for tuple access

* rustfmt

ethers-contract/ethers-contract-derive/src/display.rs

@@ -1,9 +1,9 @@
 //! Helper functions for deriving `Display`
 
 use proc_macro2::TokenStream;
-use quote::{format_ident, quote};
+use quote::quote;
 use syn::spanned::Spanned as _;
-use syn::{parse::Error, Data, DeriveInput, Fields};
+use syn::{parse::Error, Data, DeriveInput, Fields, Index};
 
 use ethers_contract_abigen::ethers_core_crate;
 use ethers_core::abi::ParamType;
@@ -40,7 +40,11 @@ pub(crate) fn derive_eth_display_impl(input: DeriveInput) -> Result<TokenStream,
         let ident = field
             .ident
             .clone()
-            .unwrap_or_else(|| format_ident!("{}", idx));
+            .map(|id| quote! {#id})
+            .unwrap_or_else(|| {
+                let idx = Index::from(idx);
+                quote! {#idx}
+            });
         let tokens = if let Ok(param) = utils::find_parameter_type(&field.ty) {
             match param {
                 ParamType::Address | ParamType::Uint(_) | ParamType::Int(_) => {

ethers-contract/src/multicall/mod.rs

@@ -212,9 +212,11 @@ impl<M: Middleware> Multicall<M> {
     /// If more than the maximum number of supported calls are added. The maximum
     /// limits is constrained due to tokenization/detokenization support for tuples
     pub fn add_call<D: Detokenize>(&mut self, call: ContractCall<M, D>) -> &mut Self {
-        if self.calls.len() >= 16 {
-            panic!("Cannot support more than {} calls", 16);
-        }
+        assert!(
+            !(self.calls.len() >= 16),
+            "Cannot support more than {} calls",
+            16
+        );
 
         match (call.tx.to(), call.tx.data()) {
             (Some(NameOrAddress::Address(target)), Some(data)) => {

ethers-contract/tests/common/derive.rs

@@ -371,3 +371,21 @@ fn eth_display_works() {
 
     assert_eq!(val, format!("{}", item));
 }
+
+#[test]
+fn eth_display_works_for_human_readable() {
+    ethers_contract::abigen!(
+        HevmConsole,
+        r#"[
+            event log(string)
+            event log2(string x)
+            ]"#,
+    );
+
+    let log = LogFilter("abc".to_string());
+    assert_eq!("abc".to_string(), format!("{}", log));
+    let log = Log2Filter {
+        x: "abc".to_string(),
+    };
+    assert_eq!("abc".to_string(), format!("{}", log));
+}