feat: function call enums EthCall macro and more

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Unreleased
 
+- add `EthCall` trait and derive macro which generates matching structs for contract calls [#517](https://github.com/gakonst/ethers-rs/pull/517)
 - `abigen!` now generates `Display` for all events using the new `EthDisplay` macro [#513](https://github.com/gakonst/ethers-rs/pull/513)
 - `abigen!` now supports overloaded functions natively [#501](https://github.com/gakonst/ethers-rs/pull/501)
 - `abigen!` now supports multiple contracts [#498](https://github.com/gakonst/ethers-rs/pull/498)

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

@@ -29,6 +29,8 @@ pub struct ExpandedContract {
  pub contract: TokenStream,
  /// All event impls of the contract
  pub events: TokenStream,
+ /// All contract call struct related types
+ pub call_structs: TokenStream,
  /// The contract's internal structs
  pub abi_structs: TokenStream,
 }
@@ -41,6 +43,7 @@ impl ExpandedContract {
  imports,
  contract,
  events,
+ call_structs,
  abi_structs,
  } = self;
  quote! {
@@ -52,6 +55,7 @@ impl ExpandedContract {
  #imports
  #contract
  #events
+ #call_structs
  #abi_structs
  }
  }
@@ -111,8 +115,8 @@ impl Context {
  // 3. impl block for the event functions
  let contract_events = self.event_methods()?;
 
- // 4. impl block for the contract methods
- let contract_methods = self.methods()?;
+ // 4. impl block for the contract methods and their corresponding types
+ let (contract_methods, call_structs) = self.methods_and_call_structs()?;
 
  // 5. Declare the structs parsed from the human readable abi
  let abi_structs_decl = self.abi_structs()?;
@@ -146,6 +150,7 @@ impl Context {
  imports,
  contract,
  events: events_decl,
+ call_structs,
  abi_structs: abi_structs_decl,
  })
  }

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

@@ -5,7 +5,6 @@ use inflector::Inflector;
 use proc_macro2::{Ident, Literal, TokenStream};
 use quote::quote;
 use std::collections::BTreeMap;
-use syn::Path;
 
 impl Context {
  /// Expands each event to a struct + its impl Detokenize block
@@ -33,9 +32,10 @@ impl Context {
 
  /// Generate the event filter methods for the contract
  pub fn event_methods(&self) -> Result<TokenStream> {
- let sorted_events: BTreeMap<_, _> = self.abi.events.clone().into_iter().collect();
+ let sorted_events: BTreeMap<_, _> = self.abi.events.iter().collect();
  let filter_methods = sorted_events
  .values()
+ .map(std::ops::Deref::deref)
  .flatten()
  .map(|event| self.expand_filter(event))
  .collect::<Vec<_>>();
@@ -51,9 +51,9 @@ impl Context {
 
  /// Generate an enum with a variant for each event
  fn expand_events_enum(&self) -> TokenStream {
- let sorted_events: BTreeMap<_, _> = self.abi.events.clone().into_iter().collect();
-
- let variants = sorted_events
+ let variants = self
+ .abi
+  .events
  .values()
  .flatten()
  .map(|e| expand_struct_name(e, self.event_aliases.get(&e.abi_signature()).cloned()))
@@ -65,33 +65,11 @@ impl Context {
  let ethers_contract = util::ethers_contract_crate();
 
  quote! {
- #[derive(Debug, Clone, PartialEq, Eq)]
+ #[derive(Debug, Clone, PartialEq, Eq, #ethers_contract::EthAbiType)]
  pub enum #enum_name {
  #(#variants(#variants)),*
  }
 
- impl #ethers_core::abi::Tokenizable for #enum_name {
-
- fn from_token(token: #ethers_core::abi::Token) -> Result<Self, #ethers_core::abi::InvalidOutputType> where
- Self: Sized {
- #(
- if let Ok(decoded) = #variants::from_token(token.clone()) {
- return Ok(#enum_name::#variants(decoded))
- }
- )*
- Err(#ethers_core::abi::InvalidOutputType("Failed to decode all event variants".to_string()))
- }
-
- fn into_token(self) -> #ethers_core::abi::Token {
- match self {
- #(
- #enum_name::#variants(element) => element.into_token()
- ),*
- }
- }
- }
- impl #ethers_core::abi::TokenizableItem for #enum_name { }
-
  impl #ethers_contract::EthLogDecode for #enum_name {
  fn decode_log(log: &#ethers_core::abi::RawLog) -> Result<Self, #ethers_core::abi::Error>
  where
@@ -153,8 +131,8 @@ impl Context {
 
  /// Expands an event property type.
  ///
- /// Note that this is slightly different than an expanding a Solidity type as
- /// complex types like arrays and strings get emited as hashes when they are
+ /// Note that this is slightly different from expanding a Solidity type as
+ /// complex types like arrays and strings get emitted as hashes when they are
  /// indexed.
  /// If a complex types matches with a struct previously parsed by the AbiParser,
  /// we can replace it
@@ -213,8 +191,8 @@ impl Context {
  })
  }
 
- /// Expands an ABI event into name-type pairs for each of its parameters.
- fn expand_params(&self, event: &Event) -> Result<Vec<(TokenStream, TokenStream, bool)>> {
+ /// Expands the name-type pairs for the given inputs
+ fn expand_event_params(&self, event: &Event) -> Result<Vec<(TokenStream, TokenStream, bool)>> {
  event
  .inputs
  .iter()
@@ -264,7 +242,7 @@ impl Context {
 
  let event_name = expand_struct_name(event, sig);
 
- let params = self.expand_params(event)?;
+ let params = self.expand_event_params(event)?;
  // expand as a tuple if all fields are anonymous
  let all_anonymous_fields = event.inputs.iter().all(|input| input.name.is_empty());
  let data_type_definition = if all_anonymous_fields {
@@ -273,7 +251,7 @@ impl Context {
  expand_data_struct(&event_name, &params)
  };
 
- let derives = expand_derives(&self.event_derives);
+ let derives = util::expand_derives(&self.event_derives);
 
  let ethers_contract = util::ethers_contract_crate();
 
@@ -323,16 +301,20 @@ fn expand_data_struct(name: &Ident, params: &[(TokenStream, TokenStream, bool)])
 fn expand_data_tuple(name: &Ident, params: &[(TokenStream, TokenStream, bool)]) -> TokenStream {
  let fields = params
  .iter()
- .map(|(_, ty, _)| quote! { pub #ty })
+ .map(|(_, ty, indexed)| {
+ if *indexed {
+ quote! {
+ #[ethevent(indexed)] pub #ty }
+ } else {
+ quote! {
+ pub #ty }
+ }
+ })
  .collect::<Vec<_>>();
 
  quote! { struct #name( #( #fields ),* ); }
 }
 
-fn expand_derives(derives: &[Path]) -> TokenStream {
- quote! {#(#derives),*}
-}
-
 #[cfg(test)]
 mod tests {
  use super::*;
@@ -450,7 +432,7 @@ mod tests {
  };
 
  let cx = test_context();
- let params = cx.expand_params(&event).unwrap();
+ let params = cx.expand_event_params(&event).unwrap();
  let name = expand_struct_name(&event, None);
  let definition = expand_data_struct(&name, &params);
 
@@ -482,7 +464,7 @@ mod tests {
  };
 
  let cx = test_context_with_alias("Foo(bool,address)", "FooAliased");
- let params = cx.expand_params(&event).unwrap();
+ let params = cx.expand_event_params(&event).unwrap();
  let alias = Some(util::ident("FooAliased"));
  let name = expand_struct_name(&event, alias);
  let definition = expand_data_struct(&name, &params);
@@ -515,7 +497,7 @@ mod tests {
  };
 
  let cx = test_context();
- let params = cx.expand_params(&event).unwrap();
+ let params = cx.expand_event_params(&event).unwrap();
  let name = expand_struct_name(&event, None);
  let definition = expand_data_tuple(&name, &params);
 
@@ -544,7 +526,7 @@ mod tests {
  };
 
  let cx = test_context_with_alias("Foo(bool,address)", "FooAliased");
- let params = cx.expand_params(&event).unwrap();
+ let params = cx.expand_event_params(&event).unwrap();
  let alias = Some(util::ident("FooAliased"));
  let name = expand_struct_name(&event, alias);
  let definition = expand_data_tuple(&name, &params);