refactor(abigen): inline docs (#2090)

* refactor: abigen docs

* chore: doc

* refactor: final doc

* mergings

* fix: unremove Default

ethers-contract/ethers-contract-abigen/src/contract/common.rs

@@ -62,7 +62,7 @@ where
 }
 
 pub(crate) fn imports(name: &str) -> TokenStream {
-    let doc = util::expand_doc(&format!("{name} was auto-generated with ethers-rs Abigen. More information at: https://github.com/gakonst/ethers-rs"));
+    let doc_str = format!("{name} was auto-generated with ethers-rs Abigen. More information at: https://github.com/gakonst/ethers-rs");
 
     let ethers_core = ethers_core_crate();
     let ethers_providers = ethers_providers_crate();
@@ -73,7 +73,7 @@ pub(crate) fn imports(name: &str) -> TokenStream {
         #![allow(dead_code)]
         #![allow(clippy::type_complexity)]
         #![allow(unused_imports)]
-        #doc
+        #![doc = #doc_str]
 
         use std::sync::Arc;
         use #ethers_core::{

ethers-contract/ethers-contract-abigen/src/contract/errors.rs

@@ -59,13 +59,12 @@ impl Context {
             expand_data_struct(&error_name, &fields)
         };
 
-        let doc = format!(
+        let doc_str = format!(
             "Custom Error type `{}` with signature `{}` and selector `0x{}`",
             error.name,
             abi_signature,
             hex::encode(&error.selector()[..])
         );
-        let abi_signature_doc = util::expand_doc(&doc);
         let ethers_contract = ethers_contract_crate();
         // use the same derives as for events
         let derives = util::expand_derives(&self.event_derives);
@@ -73,9 +72,9 @@ impl Context {
         let error_name = &error.name;
 
         Ok(quote! {
-             #abi_signature_doc
+            #[doc = #doc_str]
             #[derive(Clone, Debug, Default, Eq, PartialEq, #ethers_contract::EthError, #ethers_contract::EthDisplay, #derives)]
-            #[etherror( name = #error_name, abi = #abi_signature )]
+            #[etherror(name = #error_name, abi = #abi_signature)]
             pub #data_type_definition
         })
     }

ethers-contract/ethers-contract-abigen/src/contract/events.rs

@@ -217,24 +217,25 @@ impl Context {
 
     /// Expands into a single method for contracting an event stream.
     fn expand_filter(&self, event: &Event) -> TokenStream {
-        let ethers_contract = ethers_contract_crate();
+        let name = &event.name;
         let alias = self.event_aliases.get(&event.abi_signature()).cloned();
 
-        let name = if let Some(id) = alias.clone() {
+        // append `filter` to disambiguate with potentially conflicting
+        // function names
+        let function_name = if let Some(id) = alias.clone() {
             util::safe_ident(&format!("{}_filter", id.to_string().to_snake_case()))
         } else {
             util::safe_ident(&format!("{}_filter", event.name.to_snake_case()))
         };
+        let struct_name = event_struct_name(name, alias);
 
-        // append `filter` to disambiguate with potentially conflicting
+        let doc_str = format!("Gets the contract's `{name}` event");
-        // function names
 
-        let result = event_struct_name(&event.name, alias);
+        let ethers_contract = ethers_contract_crate();
 
-        let doc = util::expand_doc(&format!("Gets the contract's `{}` event", event.name));
         quote! {
-            #doc
+            #[doc = #doc_str]
-            pub fn #name(&self) -> #ethers_contract::builders::Event<M, #result> {
+            pub fn #function_name(&self) -> #ethers_contract::builders::Event<M, #struct_name> {
                 self.0.event()
             }
         }

ethers-contract/ethers-contract-abigen/src/contract/methods.rs

@@ -124,13 +124,11 @@ impl Context {
         };
         let function_name = &function.name;
         let abi_signature = function.abi_signature();
-        let doc = format!(
+        let doc_str = format!(
-            "Container type for all input parameters for the `{}` function with signature `{}` and selector `0x{}`",
+            "Container type for all input parameters for the `{function_name}` function with signature `{abi_signature}` and selector `0x{}`",
-            function.name,
-            abi_signature,
             hex::encode(&function.selector()[..])
         );
-        let abi_signature_doc = util::expand_doc(&doc);
+
         let ethers_contract = ethers_contract_crate();
         // use the same derives as for events
         let derives = util::expand_derives(&self.event_derives);
@@ -146,7 +144,7 @@ impl Context {
         };
 
         Ok(quote! {
-            #abi_signature_doc
+            #[doc = #doc_str]
             #[derive(Clone, Debug, Eq, PartialEq, #ethers_contract::EthCall, #ethers_contract::EthDisplay, #derives)]
             #derive_default
             #[ethcall( name = #function_name, abi = #abi_signature )]
@@ -160,6 +158,7 @@ impl Context {
         function: &Function,
         alias: Option<&MethodAlias>,
     ) -> Result<TokenStream> {
+        let name = &function.name;
         let struct_name = expand_return_struct_name(function, alias);
         let fields = self.expand_output_params(function)?;
         // no point in having structs when there is no data returned
@@ -176,13 +175,11 @@ impl Context {
             expand_data_struct(&struct_name, &fields)
         };
         let abi_signature = function.abi_signature();
-        let doc = format!(
+        let doc_str = format!(
-            "Container type for all return fields from the `{}` function with signature `{}` and selector `0x{}`",
+            "Container type for all return fields from the `{name}` function with signature `{abi_signature}` and selector `0x{}`",
-            function.name,
-            abi_signature,
             hex::encode(&function.selector()[..])
         );
-        let abi_signature_doc = util::expand_doc(&doc);
+
         let ethers_contract = ethers_contract_crate();
         // use the same derives as for events
         let derives = util::expand_derives(&self.event_derives);
@@ -198,9 +195,9 @@ impl Context {
         };
 
         Ok(quote! {
-            #abi_signature_doc
+            #[doc = #doc_str]
             #[derive(Clone, Debug,Eq, PartialEq, #ethers_contract::EthAbiType, #ethers_contract::EthAbiCodec, #derives)]
-             #derive_default
+            #derive_default
             pub #return_type_definition
         })
     }
@@ -436,10 +433,11 @@ impl Context {
         function: &Function,
         alias: Option<MethodAlias>,
     ) -> Result<TokenStream> {
-        let ethers_contract = ethers_contract_crate();
+        let name = &function.name;
+        let function_name = expand_function_name(function, alias.as_ref());
+        let selector = function.selector();
 
-        let name = expand_function_name(function, alias.as_ref());
+        let selector_tokens = expand_selector(selector);
-        let selector = expand_selector(function.selector());
 
         let contract_args = self.expand_contract_call_args(function)?;
         let function_params =
@@ -448,18 +446,15 @@ impl Context {
 
         let outputs = self.expand_outputs(function)?;
 
-        let result = quote! { #ethers_contract::builders::ContractCall<M, #outputs> };
+        let doc_str =
+            format!("Calls the contract's `{name}` (0x{}) function", hex::encode(selector));
+
+        let ethers_contract = ethers_contract_crate();
 
-        let doc = util::expand_doc(&format!(
-            "Calls the contract's `{}` (0x{}) function",
-            function.name,
-            hex::encode(function.selector())
-        ));
         Ok(quote! {
-
+            #[doc = #doc_str]
-            #doc
+            pub fn #function_name(&self #function_params) -> #ethers_contract::builders::ContractCall<M, #outputs> {
-            pub fn #name(&self #function_params) -> #result {
+                self.0.method_hash(#selector_tokens, #contract_args)
-                self.0.method_hash(#selector, #contract_args)
                     .expect("method not found (this should never happen)")
             }
         })
@@ -470,9 +465,10 @@ impl Context {
     ///
     /// In case of overloaded functions we would follow rust's general
     /// convention of suffixing the function name with _with
-    // The first function or the function with the least amount of arguments should
+    ///
-    // be named as in the ABI, the following functions suffixed with _with_ +
+    /// The first function or the function with the least amount of arguments should
-    // additional_params[0].name + (_and_(additional_params[1+i].name))*
+    /// be named as in the ABI, the following functions suffixed with _with_ +
+    /// additional_params[0].name + (_and_(additional_params[1+i].name))*
     fn get_method_aliases(&self) -> Result<BTreeMap<String, MethodAlias>> {
         let mut aliases = self.method_aliases.clone();
 

ethers-contract/ethers-contract-abigen/src/contract/structs.rs

@@ -123,22 +123,18 @@ impl Context {
             }
         };
 
-        let sig = if let ParamType::Tuple(ref tokens) = tuple {
+        let sig = match tuple {
-            tokens.iter().map(|kind| kind.to_string()).collect::<Vec<_>>().join(",")
+            ParamType::Tuple(ref types) if !types.is_empty() => util::abi_signature_types(types),
-        } else {
+            _ => String::new(),
-            "".to_string()
         };
-
+        let doc_str = format!("`{name}({sig})`");
-        let abi_signature = format!("{name}({sig})",);
-
-        let abi_signature_doc = util::expand_doc(&format!("`{abi_signature}`"));
 
         // use the same derives as for events
         let derives = util::expand_derives(&self.event_derives);
 
         let ethers_contract = ethers_contract_crate();
         Ok(quote! {
-            #abi_signature_doc
+            #[doc = #doc_str]
             #[derive(Clone, Debug, Default, Eq, PartialEq, #ethers_contract::EthAbiType, #ethers_contract::EthAbiCodec, #derives)]
             #struct_def
         })
@@ -178,13 +174,7 @@ impl Context {
             }
         }
 
-        let abi_signature = format!(
+        let abi_signature = util::abi_signature(name, &param_types);
-            "{}({})",
-            name,
-            param_types.iter().map(|kind| kind.to_string()).collect::<Vec<_>>().join(","),
-        );
-
-        let abi_signature_doc = util::expand_doc(&format!("`{abi_signature}`"));
 
         let name = util::ident(name);
 
@@ -195,7 +185,7 @@ impl Context {
         let ethers_contract = ethers_contract_crate();
 
         Ok(quote! {
-            #abi_signature_doc
+            #[doc = #abi_signature]
             #[derive(Clone, Debug, Default, Eq, PartialEq, #ethers_contract::EthAbiType, #ethers_contract::EthAbiCodec, #derives)]
             pub struct #name {
                 #( #fields ),*

ethers-contract/ethers-contract-abigen/src/util.rs

@@ -1,7 +1,7 @@
 use ethers_core::abi::{Param, ParamType};
 use eyre::Result;
 use inflector::Inflector;
-use proc_macro2::{Ident, Literal, Span, TokenStream};
+use proc_macro2::{Ident, Span, TokenStream};
 use quote::quote;
 use std::path::PathBuf;
 use syn::{Ident as SynIdent, Path};
@@ -81,14 +81,6 @@ pub fn expand_input_name(index: usize, name: &str) -> TokenStream {
     quote! { #name }
 }
 
-/// Expands a doc string into an attribute token stream.
-pub fn expand_doc(s: &str) -> TokenStream {
-    let doc = Literal::string(s);
-    quote! {
-        #[doc = #doc]
-    }
-}
-
 pub fn expand_derives(derives: &[Path]) -> TokenStream {
     quote! {#(#derives),*}
 }
@@ -167,13 +159,16 @@ pub fn json_files(root: impl AsRef<std::path::Path>) -> Vec<PathBuf> {
         .collect()
 }
 
-/// rust-std derives `Default` automatically only for arrays len <= 32
+/// Returns whether all the given parameters can derive [`Default`].
 ///
-/// Returns whether the corresponding struct can derive `Default`
+/// rust-std derives `Default` automatically only for arrays len <= 32
-pub fn can_derive_defaults(params: &[Param]) -> bool {
+pub fn can_derive_defaults<'a>(params: impl IntoIterator<Item = &'a Param>) -> bool {
-    params.iter().map(|param| &param.kind).all(can_derive_default)
+    params.into_iter().map(|param| &param.kind).all(can_derive_default)
 }
 
+/// Returns whether the given type can derive [`Default`].
+///
+/// rust-std derives `Default` automatically only for arrays len <= 32
 pub fn can_derive_default(param: &ParamType) -> bool {
     const MAX_SUPPORTED_LEN: usize = 32;
     match param {
@@ -190,6 +185,21 @@ pub fn can_derive_default(param: &ParamType) -> bool {
     }
 }
 
+/// Returns the formatted Solidity ABI signature.
+pub fn abi_signature<'a, N, T>(name: N, types: T) -> String
+where
+    N: std::fmt::Display,
+    T: IntoIterator<Item = &'a ParamType>,
+{
+    let types = abi_signature_types(types);
+    format!("`{name}({types})`")
+}
+
+/// Returns the Solidity stringified ABI types joined by a single comma.
+pub fn abi_signature_types<'a, T: IntoIterator<Item = &'a ParamType>>(types: T) -> String {
+    types.into_iter().map(ToString::to_string).collect::<Vec<_>>().join(",")
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;