git.delta.rocks / unique-network / refs/commits / b6f414fb480e

difftreelog

refactor(evm-coder)! manual macro parsing

Yaroslav Bolyukin2022-07-12parent: #34aa637.patch.diff
in: master
We have plans to allow evm-coder to generate Callables for externally defined contracts, however our current attribute parsing was limiting code maintanability, rework was needed before starting to implement new features

BREAKING CHANGE: solidity_interface definitions may now look slightly different, for example interface names now should be identifiers, not strings

8 files changed

modifiedcrates/evm-coder-macros/Cargo.tomldiffbeforeafterboth
--- a/crates/evm-coder-macros/Cargo.toml
+++ b/crates/evm-coder-macros/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "evm-coder-macros"
-version = "0.1.0"
+version = "0.2.0"
 license = "GPLv3"
 edition = "2021"
 
@@ -8,10 +8,9 @@
 proc-macro = true
 
 [dependencies]
-sha3 = "0.9.1"
+sha3 = "0.10.1"
 quote = "1.0"
 proc-macro2 = "1.0"
 syn = { version = "1.0", features = ["full"] }
 hex = "0.4.3"
 Inflector = "0.11.4"
-darling = "0.13.0"
modifiedcrates/evm-coder-macros/src/lib.rsdiffbeforeafterboth
before · crates/evm-coder-macros/src/lib.rs
1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617#![allow(dead_code)]1819use darling::FromMeta;20use inflector::cases;21use proc_macro::TokenStream;22use quote::quote;23use sha3::{Digest, Keccak256};24use syn::{25	AttributeArgs, DeriveInput, GenericArgument, Ident, ItemImpl, Pat, Path, PathArguments,26	PathSegment, Type, parse_macro_input, spanned::Spanned,27};2829mod solidity_interface;30mod to_log;3132fn fn_selector_str(input: &str) -> u32 {33	let mut hasher = Keccak256::new();34	hasher.update(input.as_bytes());35	let result = hasher.finalize();3637	let mut selector_bytes = [0; 4];38	selector_bytes.copy_from_slice(&result[0..4]);3940	u32::from_be_bytes(selector_bytes)41}4243/// Returns solidity function selector (first 4 bytes of hash) by its44/// textual representation45///46/// ```ignore47/// use evm_coder_macros::fn_selector;48///49/// assert_eq!(fn_selector!(transfer(address, uint256)), 0xa9059cbb);50/// ```51#[proc_macro]52pub fn fn_selector(input: TokenStream) -> TokenStream {53	let input = input.to_string().replace(' ', "");54	let selector = fn_selector_str(&input);5556	(quote! {57		#selector58	})59	.into()60}6162fn event_selector_str(input: &str) -> [u8; 32] {63	let mut hasher = Keccak256::new();64	hasher.update(input.as_bytes());65	let result = hasher.finalize();6667	let mut selector_bytes = [0; 32];68	selector_bytes.copy_from_slice(&result[0..32]);69	selector_bytes70}7172/// Returns solidity topic (hash) by its textual representation73///74/// ```ignore75/// use evm_coder_macros::event_topic;76///77/// assert_eq!(78///     format!("{:x}", event_topic!(Transfer(address, address, uint256))),79///     "ddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",80/// );81/// ```82#[proc_macro]83pub fn event_topic(stream: TokenStream) -> TokenStream {84	let input = stream.to_string().replace(' ', "");85	let selector_bytes = event_selector_str(&input);8687	(quote! {88		::primitive_types::H256([#(89			#selector_bytes,90		)*])91	})92	.into()93}9495fn parse_path(ty: &Type) -> syn::Result<&Path> {96	match &ty {97		syn::Type::Path(pat) => {98			if let Some(qself) = &pat.qself {99				return Err(syn::Error::new(qself.ty.span(), "no receiver expected"));100			}101			Ok(&pat.path)102		}103		_ => Err(syn::Error::new(ty.span(), "expected ty to be path")),104	}105}106107fn parse_path_segment(path: &Path) -> syn::Result<&PathSegment> {108	if path.segments.len() != 1 {109		return Err(syn::Error::new(110			path.span(),111			"expected path to have only segment",112		));113	}114	let last_segment = &path.segments.last().unwrap();115	Ok(last_segment)116}117118fn parse_ident_from_pat(pat: &Pat) -> syn::Result<&Ident> {119	match pat {120		Pat::Ident(i) => Ok(&i.ident),121		_ => Err(syn::Error::new(pat.span(), "expected pat ident")),122	}123}124125fn parse_ident_from_segment(segment: &PathSegment, allow_generics: bool) -> syn::Result<&Ident> {126	if segment.arguments != PathArguments::None && !allow_generics {127		return Err(syn::Error::new(128			segment.arguments.span(),129			"unexpected generic type",130		));131	}132	Ok(&segment.ident)133}134135fn parse_ident_from_path(path: &Path, allow_generics: bool) -> syn::Result<&Ident> {136	let segment = parse_path_segment(path)?;137	parse_ident_from_segment(segment, allow_generics)138}139140fn parse_ident_from_type(ty: &Type, allow_generics: bool) -> syn::Result<&Ident> {141	let path = parse_path(ty)?;142	parse_ident_from_path(path, allow_generics)143}144145// Gets T out of Result<T>146fn parse_result_ok(ty: &Type) -> syn::Result<&Type> {147	let path = parse_path(ty)?;148	let segment = parse_path_segment(path)?;149150	if segment.ident != "Result" {151		return Err(syn::Error::new(152			ty.span(),153			"expected Result as return type (no renamed aliases allowed)",154		));155	}156	let args = match &segment.arguments {157		PathArguments::AngleBracketed(e) => e,158		_ => {159			return Err(syn::Error::new(160				segment.arguments.span(),161				"missing Result generics",162			))163		}164	};165166	let args = &args.args;167	let arg = args.first().unwrap();168169	let ty = match arg {170		GenericArgument::Type(ty) => ty,171		_ => {172			return Err(syn::Error::new(173				arg.span(),174				"expected first generic to be type",175			))176		}177	};178179	Ok(ty)180}181182fn pascal_ident_to_call(ident: &Ident) -> Ident {183	let name = format!("{}Call", ident);184	Ident::new(&name, ident.span())185}186fn snake_ident_to_pascal(ident: &Ident) -> Ident {187	let name = ident.to_string();188	let name = cases::pascalcase::to_pascal_case(&name);189	Ident::new(&name, ident.span())190}191fn snake_ident_to_screaming(ident: &Ident) -> Ident {192	let name = ident.to_string();193	let name = cases::screamingsnakecase::to_screaming_snake_case(&name);194	Ident::new(&name, ident.span())195}196fn pascal_ident_to_snake_call(ident: &Ident) -> Ident {197	let name = ident.to_string();198	let name = cases::snakecase::to_snake_case(&name);199	let name = format!("call_{}", name);200	Ident::new(&name, ident.span())201}202203/// Derives call enum implementing [`evm_coder::Callable`], [`evm_coder::Weighted`]204/// and [`evm_coder::Call`] from impl block205///206/// ## Macro syntax207///208/// `#[solidity_interface(name, is, inline_is, events)]`209/// - *name*: used in generated code, and for Call enum name210/// - *is*: used to provide call inheritance, not found methods will be delegated to all contracts211/// specified in is/inline_is212/// - *inline_is*: same as is, but selectors for passed contracts will be used by derived ERC165213/// implementation214///215/// `#[weight(value)]`216/// Can be added to every method of impl block, used for deriving [`evm_coder::Weighted`], which217/// is used by substrate bridge218/// - *value*: expression, which evaluates to weight required to call this method.219/// This expression can use call arguments to calculate non-constant execution time.220/// This expression should evaluate faster than actual execution does, and may provide worser case221/// than one is called222///223/// `#[solidity_interface(rename_selector)]`224/// - *rename_selector*: by default, selector name will be generated by transforming method name225/// from snake_case to camelCase. Use this option, if other naming convention is required.226/// I.e: method `token_uri` will be automatically renamed to `tokenUri` in selector, but name227/// required by ERC721 standard is `tokenURI`, thus we need to specify `rename_selector = "tokenURI"`228/// explicitly229///230/// Also, any contract method may have doc comments, which will be automatically added to generated231/// solidity interface definitions232///233/// ## Example234///235/// ```ignore236/// struct SuperContract;237/// struct InlineContract;238/// struct Contract;239///240/// #[derive(ToLog)]241/// enum ContractEvents {242///     Event(#[indexed] uint32),243/// }244///245/// #[solidity_interface(name = "MyContract", is(SuperContract), inline_is(InlineContract))]246/// impl Contract {247///     /// Multiply two numbers248///     #[weight(200 + a + b)]249///     #[solidity_interface(rename_selector = "mul")]250///     fn mul(&mut self, a: uint32, b: uint32) -> Result<uint32> {251///         Ok(a.checked_mul(b).ok_or("overflow")?)252///     }253/// }254/// ```255#[proc_macro_attribute]256pub fn solidity_interface(args: TokenStream, stream: TokenStream) -> TokenStream {257	let args = parse_macro_input!(args as AttributeArgs);258	let args = solidity_interface::InterfaceInfo::from_list(&args).unwrap();259260	let input: ItemImpl = match syn::parse(stream) {261		Ok(t) => t,262		Err(e) => return e.to_compile_error().into(),263	};264265	let expanded = match solidity_interface::SolidityInterface::try_from(args, &input) {266		Ok(v) => v.expand(),267		Err(e) => e.to_compile_error(),268	};269270	(quote! {271		#input272273		#expanded274	})275	.into()276}277278#[proc_macro_attribute]279pub fn solidity(_args: TokenStream, stream: TokenStream) -> TokenStream {280	stream281}282#[proc_macro_attribute]283pub fn weight(_args: TokenStream, stream: TokenStream) -> TokenStream {284	stream285}286287/// ## Syntax288///289/// `#[indexed]`290/// Marks this field as indexed, so it will appear in [`ethereum::Log`] topics instead of data291#[proc_macro_derive(ToLog, attributes(indexed))]292pub fn to_log(value: TokenStream) -> TokenStream {293	let input = parse_macro_input!(value as DeriveInput);294295	match to_log::Events::try_from(&input) {296		Ok(e) => e.expand(),297		Err(e) => e.to_compile_error(),298	}299	.into()300}
after · crates/evm-coder-macros/src/lib.rs
1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617#![allow(dead_code)]1819use inflector::cases;20use proc_macro::TokenStream;21use quote::quote;22use sha3::{Digest, Keccak256};23use syn::{24	DeriveInput, GenericArgument, Ident, ItemImpl, Pat, Path, PathArguments,25	PathSegment, Type, parse_macro_input, spanned::Spanned, Attribute, parse::Parse,26};2728mod solidity_interface;29mod to_log;3031fn fn_selector_str(input: &str) -> u32 {32	let mut hasher = Keccak256::new();33	hasher.update(input.as_bytes());34	let result = hasher.finalize();3536	let mut selector_bytes = [0; 4];37	selector_bytes.copy_from_slice(&result[0..4]);3839	u32::from_be_bytes(selector_bytes)40}4142/// Returns solidity function selector (first 4 bytes of hash) by its43/// textual representation44///45/// ```ignore46/// use evm_coder_macros::fn_selector;47///48/// assert_eq!(fn_selector!(transfer(address, uint256)), 0xa9059cbb);49/// ```50#[proc_macro]51pub fn fn_selector(input: TokenStream) -> TokenStream {52	let input = input.to_string().replace(' ', "");53	let selector = fn_selector_str(&input);5455	(quote! {56		#selector57	})58	.into()59}6061fn event_selector_str(input: &str) -> [u8; 32] {62	let mut hasher = Keccak256::new();63	hasher.update(input.as_bytes());64	let result = hasher.finalize();6566	let mut selector_bytes = [0; 32];67	selector_bytes.copy_from_slice(&result[0..32]);68	selector_bytes69}7071/// Returns solidity topic (hash) by its textual representation72///73/// ```ignore74/// use evm_coder_macros::event_topic;75///76/// assert_eq!(77///     format!("{:x}", event_topic!(Transfer(address, address, uint256))),78///     "ddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",79/// );80/// ```81#[proc_macro]82pub fn event_topic(stream: TokenStream) -> TokenStream {83	let input = stream.to_string().replace(' ', "");84	let selector_bytes = event_selector_str(&input);8586	(quote! {87		::primitive_types::H256([#(88			#selector_bytes,89		)*])90	})91	.into()92}9394fn parse_path(ty: &Type) -> syn::Result<&Path> {95	match &ty {96		syn::Type::Path(pat) => {97			if let Some(qself) = &pat.qself {98				return Err(syn::Error::new(qself.ty.span(), "no receiver expected"));99			}100			Ok(&pat.path)101		}102		_ => Err(syn::Error::new(ty.span(), "expected ty to be path")),103	}104}105106fn parse_path_segment(path: &Path) -> syn::Result<&PathSegment> {107	if path.segments.len() != 1 {108		return Err(syn::Error::new(109			path.span(),110			"expected path to have only segment",111		));112	}113	let last_segment = &path.segments.last().unwrap();114	Ok(last_segment)115}116117fn parse_ident_from_pat(pat: &Pat) -> syn::Result<&Ident> {118	match pat {119		Pat::Ident(i) => Ok(&i.ident),120		_ => Err(syn::Error::new(pat.span(), "expected pat ident")),121	}122}123124fn parse_ident_from_segment(segment: &PathSegment, allow_generics: bool) -> syn::Result<&Ident> {125	if segment.arguments != PathArguments::None && !allow_generics {126		return Err(syn::Error::new(127			segment.arguments.span(),128			"unexpected generic type",129		));130	}131	Ok(&segment.ident)132}133134fn parse_ident_from_path(path: &Path, allow_generics: bool) -> syn::Result<&Ident> {135	let segment = parse_path_segment(path)?;136	parse_ident_from_segment(segment, allow_generics)137}138139fn parse_ident_from_type(ty: &Type, allow_generics: bool) -> syn::Result<&Ident> {140	let path = parse_path(ty)?;141	parse_ident_from_path(path, allow_generics)142}143144// Gets T out of Result<T>145fn parse_result_ok(ty: &Type) -> syn::Result<&Type> {146	let path = parse_path(ty)?;147	let segment = parse_path_segment(path)?;148149	if segment.ident != "Result" {150		return Err(syn::Error::new(151			ty.span(),152			"expected Result as return type (no renamed aliases allowed)",153		));154	}155	let args = match &segment.arguments {156		PathArguments::AngleBracketed(e) => e,157		_ => {158			return Err(syn::Error::new(159				segment.arguments.span(),160				"missing Result generics",161			))162		}163	};164165	let args = &args.args;166	let arg = args.first().unwrap();167168	let ty = match arg {169		GenericArgument::Type(ty) => ty,170		_ => {171			return Err(syn::Error::new(172				arg.span(),173				"expected first generic to be type",174			))175		}176	};177178	Ok(ty)179}180181fn pascal_ident_to_call(ident: &Ident) -> Ident {182	let name = format!("{}Call", ident);183	Ident::new(&name, ident.span())184}185fn snake_ident_to_pascal(ident: &Ident) -> Ident {186	let name = ident.to_string();187	let name = cases::pascalcase::to_pascal_case(&name);188	Ident::new(&name, ident.span())189}190fn snake_ident_to_screaming(ident: &Ident) -> Ident {191	let name = ident.to_string();192	let name = cases::screamingsnakecase::to_screaming_snake_case(&name);193	Ident::new(&name, ident.span())194}195fn pascal_ident_to_snake_call(ident: &Ident) -> Ident {196	let name = ident.to_string();197	let name = cases::snakecase::to_snake_case(&name);198	let name = format!("call_{}", name);199	Ident::new(&name, ident.span())200}201202/// Derives call enum implementing [`evm_coder::Callable`], [`evm_coder::Weighted`]203/// and [`evm_coder::Call`] from impl block204///205/// ## Macro syntax206///207/// `#[solidity_interface(name, is, inline_is, events)]`208/// - *name*: used in generated code, and for Call enum name209/// - *is*: used to provide call inheritance, not found methods will be delegated to all contracts210/// specified in is/inline_is211/// - *inline_is*: same as is, but selectors for passed contracts will be used by derived ERC165212/// implementation213///214/// `#[weight(value)]`215/// Can be added to every method of impl block, used for deriving [`evm_coder::Weighted`], which216/// is used by substrate bridge217/// - *value*: expression, which evaluates to weight required to call this method.218/// This expression can use call arguments to calculate non-constant execution time.219/// This expression should evaluate faster than actual execution does, and may provide worser case220/// than one is called221///222/// `#[solidity_interface(rename_selector)]`223/// - *rename_selector*: by default, selector name will be generated by transforming method name224/// from snake_case to camelCase. Use this option, if other naming convention is required.225/// I.e: method `token_uri` will be automatically renamed to `tokenUri` in selector, but name226/// required by ERC721 standard is `tokenURI`, thus we need to specify `rename_selector = "tokenURI"`227/// explicitly228///229/// Also, any contract method may have doc comments, which will be automatically added to generated230/// solidity interface definitions231///232/// ## Example233///234/// ```ignore235/// struct SuperContract;236/// struct InlineContract;237/// struct Contract;238///239/// #[derive(ToLog)]240/// enum ContractEvents {241///     Event(#[indexed] uint32),242/// }243///244/// #[solidity_interface(name = "MyContract", is(SuperContract), inline_is(InlineContract))]245/// impl Contract {246///     /// Multiply two numbers247///     #[weight(200 + a + b)]248///     #[solidity_interface(rename_selector = "mul")]249///     fn mul(&mut self, a: uint32, b: uint32) -> Result<uint32> {250///         Ok(a.checked_mul(b).ok_or("overflow")?)251///     }252/// }253/// ```254#[proc_macro_attribute]255pub fn solidity_interface(args: TokenStream, stream: TokenStream) -> TokenStream {256	let args = parse_macro_input!(args as solidity_interface::InterfaceInfo);257258	let input: ItemImpl = match syn::parse(stream) {259		Ok(t) => t,260		Err(e) => return e.to_compile_error().into(),261	};262263	let expanded = match solidity_interface::SolidityInterface::try_from(args, &input) {264		Ok(v) => v.expand(),265		Err(e) => e.to_compile_error(),266	};267268	(quote! {269		#input270271		#expanded272	})273	.into()274}275276#[proc_macro_attribute]277pub fn solidity(_args: TokenStream, stream: TokenStream) -> TokenStream {278	stream279}280#[proc_macro_attribute]281pub fn weight(_args: TokenStream, stream: TokenStream) -> TokenStream {282	stream283}284285/// ## Syntax286///287/// `#[indexed]`288/// Marks this field as indexed, so it will appear in [`ethereum::Log`] topics instead of data289#[proc_macro_derive(ToLog, attributes(indexed))]290pub fn to_log(value: TokenStream) -> TokenStream {291	let input = parse_macro_input!(value as DeriveInput);292293	match to_log::Events::try_from(&input) {294		Ok(e) => e.expand(),295		Err(e) => e.to_compile_error(),296	}297	.into()298}
modifiedcrates/evm-coder-macros/src/solidity_interface.rsdiffbeforeafterboth
--- a/crates/evm-coder-macros/src/solidity_interface.rs
+++ b/crates/evm-coder-macros/src/solidity_interface.rs
@@ -16,14 +16,15 @@
 
 #![allow(dead_code)]
 
-use quote::quote;
-use darling::{FromMeta, ToTokens};
+use quote::{quote, ToTokens};
 use inflector::cases;
 use std::fmt::Write;
 use syn::{
 	Expr, FnArg, GenericArgument, Generics, Ident, ImplItem, ImplItemMethod, ItemImpl, Lit, Meta,
-	MetaNameValue, NestedMeta, PatType, Path, PathArguments, ReturnType, Type, spanned::Spanned,
-	parse_str,
+	MetaNameValue, PatType, PathArguments, ReturnType, Type,
+	spanned::Spanned,
+	parse::{Parse, ParseStream},
+	parenthesized, Token, LitInt, LitStr,
 };
 
 use crate::{
@@ -39,19 +40,6 @@
 	via: Option<(Type, Ident)>,
 }
 impl Is {
-	fn new_via(path: &Path, via: Option<(Type, Ident)>) -> syn::Result<Self> {
-		let name = parse_ident_from_path(path, false)?.clone();
-		Ok(Self {
-			pascal_call_name: pascal_ident_to_call(&name),
-			snake_call_name: pascal_ident_to_snake_call(&name),
-			name,
-			via,
-		})
-	}
-	fn new(path: &Path) -> syn::Result<Self> {
-		Self::new_via(path, None)
-	}
-
 	fn expand_call_def(&self, gen_ref: &proc_macro2::TokenStream) -> proc_macro2::TokenStream {
 		let name = &self.name;
 		let pascal_call_name = &self.pascal_call_name;
@@ -137,73 +125,141 @@
 
 #[derive(Default)]
 struct IsList(Vec<Is>);
-impl FromMeta for IsList {
-	fn from_list(items: &[NestedMeta]) -> darling::Result<Self> {
-		let mut out = Vec::new();
-		for item in items {
-			match item {
-				NestedMeta::Meta(Meta::Path(path)) => out.push(Is::new(path)?),
-				// TODO: replace meta parsing with manual
-				NestedMeta::Meta(Meta::List(list))
-					if list.path.is_ident("via") && list.nested.len() == 3 =>
-				{
-					let mut data = list.nested.iter();
-					let typ = match data.next().expect("len == 3") {
-						NestedMeta::Lit(Lit::Str(s)) => {
-							let v = s.value();
-							let typ: Type = parse_str(&v)?;
-							typ
-						}
-						_ => {
-							return Err(syn::Error::new(
-								item.span(),
-								"via typ should be type in string",
-							)
-							.into())
-						}
-					};
-					let via = match data.next().expect("len == 3") {
-						NestedMeta::Meta(Meta::Path(path)) => path
-							.get_ident()
-							.ok_or_else(|| syn::Error::new(item.span(), "via should be ident"))?,
-						_ => return Err(syn::Error::new(item.span(), "via should be ident").into()),
-					};
-					let path = match data.next().expect("len == 3") {
-						NestedMeta::Meta(Meta::Path(path)) => path,
-						_ => return Err(syn::Error::new(item.span(), "path should be path").into()),
-					};
-
-					out.push(Is::new_via(path, Some((typ, via.clone())))?)
-				}
-				_ => {
-					return Err(syn::Error::new(
-						item.span(),
-						"expected either Name or via(\"Type\", getter, Name)",
-					)
-					.into())
-				}
+impl Parse for IsList {
+	fn parse(input: ParseStream) -> syn::Result<Self> {
+		let mut out = vec![];
+		loop {
+			if input.is_empty() {
+				break;
+			}
+			let name = input.parse::<Ident>()?;
+			let lookahead = input.lookahead1();
+			let via = if lookahead.peek(syn::token::Paren) {
+				let contents;
+				parenthesized!(contents in input);
+				let method = contents.parse::<Ident>()?;
+				contents.parse::<Token![,]>()?;
+				let ty = contents.parse::<Type>()?;
+				Some((ty, method))
+			} else if lookahead.peek(Token![,]) {
+				None
+			} else if input.is_empty() {
+				None
+			} else {
+				return Err(lookahead.error());
+			};
+			out.push(Is {
+				pascal_call_name: pascal_ident_to_call(&name),
+				snake_call_name: pascal_ident_to_snake_call(&name),
+				name,
+				via,
+			});
+			if input.peek(Token![,]) {
+				input.parse::<Token![,]>()?;
+				continue;
+			} else {
+				break;
 			}
 		}
 		Ok(Self(out))
 	}
 }
 
-#[derive(FromMeta)]
 pub struct InterfaceInfo {
 	name: Ident,
-	#[darling(default)]
 	is: IsList,
-	#[darling(default)]
 	inline_is: IsList,
-	#[darling(default)]
 	events: IsList,
+	expect_selector: Option<u32>,
 }
+impl Parse for InterfaceInfo {
+	fn parse(input: ParseStream) -> syn::Result<Self> {
+		let mut name = None;
+		let mut is = None;
+		let mut inline_is = None;
+		let mut events = None;
+		let mut expect_selector = None;
+		// TODO: create proc-macro to optimize proc-macro boilerplate? :D
+		loop {
+			let lookahead = input.lookahead1();
+			if lookahead.peek(kw::name) {
+				let k = input.parse::<kw::name>()?;
+				input.parse::<Token![=]>()?;
+				if name.replace(input.parse::<Ident>()?).is_some() {
+					return Err(syn::Error::new(k.span(), "name is already set"));
+				}
+			} else if lookahead.peek(kw::is) {
+				let k = input.parse::<kw::is>()?;
+				let contents;
+				parenthesized!(contents in input);
+				if is.replace(contents.parse::<IsList>()?).is_some() {
+					return Err(syn::Error::new(k.span(), "is is already set"));
+				}
+			} else if lookahead.peek(kw::inline_is) {
+				let k = input.parse::<kw::inline_is>()?;
+				let contents;
+				parenthesized!(contents in input);
+				if inline_is.replace(contents.parse::<IsList>()?).is_some() {
+					return Err(syn::Error::new(k.span(), "inline_is is already set"));
+				}
+			} else if lookahead.peek(kw::events) {
+				let k = input.parse::<kw::events>()?;
+				let contents;
+				parenthesized!(contents in input);
+				if events.replace(contents.parse::<IsList>()?).is_some() {
+					return Err(syn::Error::new(k.span(), "events is already set"));
+				}
+			} else if lookahead.peek(kw::expect_selector) {
+				let k = input.parse::<kw::expect_selector>()?;
+				input.parse::<Token![=]>()?;
+				let value = input.parse::<LitInt>()?;
+				if expect_selector
+					.replace(value.base10_parse::<u32>()?)
+					.is_some()
+				{
+					return Err(syn::Error::new(k.span(), "expect_selector is already set"));
+				}
+			} else if input.is_empty() {
+				break;
+			} else {
+				return Err(lookahead.error());
+			}
+			if input.peek(Token![,]) {
+				input.parse::<Token![,]>()?;
+			} else {
+				break;
+			}
+		}
+		Ok(Self {
+			name: name.ok_or_else(|| syn::Error::new(input.span(), "missing name"))?,
+			is: is.unwrap_or_default(),
+			inline_is: inline_is.unwrap_or_default(),
+			events: events.unwrap_or_default(),
+			expect_selector,
+		})
+	}
+}
 
-#[derive(FromMeta)]
 struct MethodInfo {
-	#[darling(default)]
 	rename_selector: Option<String>,
 }
+impl Parse for MethodInfo {
+	fn parse(input: ParseStream) -> syn::Result<Self> {
+		let mut rename_selector = None;
+		let lookahead = input.lookahead1();
+		if lookahead.peek(kw::rename_selector) {
+			let k = input.parse::<kw::rename_selector>()?;
+			input.parse::<Token![=]>()?;
+			if rename_selector
+				.replace(input.parse::<LitStr>()?.value())
+				.is_some()
+			{
+				return Err(syn::Error::new(k.span(), "rename_selector is already set"));
+			}
+		}
+		Ok(Self { rename_selector })
+	}
+}
 
 enum AbiType {
 	// type
@@ -258,7 +314,7 @@
 							"expected only one generic for vec",
 						));
 					}
-					let arg = args.first().unwrap();
+					let arg = args.first().expect("first arg");
 
 					let ty = match arg {
 						GenericArgument::Type(ty) => ty,
@@ -429,23 +485,17 @@
 	Pure,
 }
 
-pub struct WeightAttr(syn::Expr);
-
-mod keyword {
+mod kw {
 	syn::custom_keyword!(weight);
-}
 
-impl syn::parse::Parse for WeightAttr {
-	fn parse(input: syn::parse::ParseStream) -> syn::Result<Self> {
-		input.parse::<syn::Token![#]>()?;
-		let content;
-		syn::bracketed!(content in input);
-		content.parse::<keyword::weight>()?;
+	syn::custom_keyword!(via);
+	syn::custom_keyword!(name);
+	syn::custom_keyword!(is);
+	syn::custom_keyword!(inline_is);
+	syn::custom_keyword!(events);
+	syn::custom_keyword!(expect_selector);
 
-		let weight_content;
-		syn::parenthesized!(weight_content in content);
-		Ok(WeightAttr(weight_content.parse::<syn::Expr>()?))
-	}
+	syn::custom_keyword!(rename_selector);
 }
 
 struct Method {
@@ -472,8 +522,7 @@
 		for attr in &value.attrs {
 			let ident = parse_ident_from_path(&attr.path, false)?;
 			if ident == "solidity" {
-				let args = attr.parse_meta().unwrap();
-				info = MethodInfo::from_meta(&args).unwrap();
+				info = attr.parse_args::<MethodInfo>()?;
 			} else if ident == "doc" {
 				let args = attr.parse_meta().unwrap();
 				let value = match args {
@@ -484,7 +533,7 @@
 				};
 				docs.push(value);
 			} else if ident == "weight" {
-				weight = Some(syn::parse2::<WeightAttr>(attr.to_token_stream())?.0);
+				weight = Some(attr.parse_args::<Expr>()?);
 			}
 		}
 		let ident = &value.sig.ident;
@@ -869,6 +918,28 @@
 			.map(|is| Is::expand_generator(is, &gen_ref));
 		let solidity_event_generators = self.info.events.0.iter().map(Is::expand_event_generator);
 
+		if let Some(expect_selector) = &self.info.expect_selector {
+			if !self.info.inline_is.0.is_empty() {
+				return syn::Error::new(
+					name.span(),
+					"expect_selector is not compatible with inline_is",
+				)
+				.to_compile_error();
+			}
+			let selector = self
+				.methods
+				.iter()
+				.map(|m| m.selector)
+				.fold(0, |a, b| a ^ b);
+
+			if *expect_selector != selector {
+				let mut methods = String::new();
+				for meth in self.methods.iter() {
+					write!(methods, "\n- {}", meth.selector_str).expect("write to string");
+				}
+				return syn::Error::new(name.span(), format!("expected selector mismatch, expected {expect_selector:0>8x}, but implementation has {selector:0>8x}{methods}")).to_compile_error();
+			}
+		}
 		// let methods = self.methods.iter().map(Method::solidity_def);
 
 		quote! {
@@ -917,9 +988,9 @@
 						)*),
 					};
 					if is_impl {
-						tc.collect("// Common stubs holder\ncontract Dummy {\n\tuint8 dummy;\n\tstring stub_error = \"this contract is implemented in native\";\n}\ncontract ERC165 is Dummy {\n\tfunction supportsInterface(bytes4 interfaceID) external view returns (bool) {\n\t\trequire(false, stub_error);\n\t\tinterfaceID;\n\t\treturn true;\n\t}\n}\n".into());
+						tc.collect("/// @dev common stubs holder\ncontract Dummy {\n\tuint8 dummy;\n\tstring stub_error = \"this contract is implemented in native\";\n}\ncontract ERC165 is Dummy {\n\tfunction supportsInterface(bytes4 interfaceID) external view returns (bool) {\n\t\trequire(false, stub_error);\n\t\tinterfaceID;\n\t\treturn true;\n\t}\n}\n".into());
 					} else {
-						tc.collect("// Common stubs holder\ninterface Dummy {\n}\ninterface ERC165 is Dummy {\n\tfunction supportsInterface(bytes4 interfaceID) external view returns (bool);\n}\n".into());
+						tc.collect("/// @dev common stubs holder\ninterface Dummy {\n}\ninterface ERC165 is Dummy {\n\tfunction supportsInterface(bytes4 interfaceID) external view returns (bool);\n}\n".into());
 					}
 					#(
 						#solidity_generators
@@ -930,9 +1001,9 @@
 
 					let mut out = string::new();
 					// In solidity interface usage (is) should be preceeded by interface definition
-					// This comment helps to sort it in a set
+					// HACK: this comment helps to sort it in a set
 					if #solidity_name.starts_with("Inline") {
-						out.push_str("// Inline\n");
+						out.push_str("/// @dev inlined interface\n");
 					}
 					let _ = interface.format(is_impl, &mut out, tc);
 					tc.collect(out);
modifiedcrates/evm-coder-macros/src/to_log.rsdiffbeforeafterboth
--- a/crates/evm-coder-macros/src/to_log.rs
+++ b/crates/evm-coder-macros/src/to_log.rs
@@ -207,7 +207,7 @@
 						)*),
 					};
 					let mut out = string::new();
-					out.push_str("// Inline\n");
+					out.push_str("/// @dev inlined interface\n");
 					let _ = interface.format(is_impl, &mut out, tc);
 					tc.collect(out);
 				}
modifiedcrates/evm-coder/src/solidity.rsdiffbeforeafterboth
--- a/crates/evm-coder/src/solidity.rs
+++ b/crates/evm-coder/src/solidity.rs
@@ -56,7 +56,7 @@
 		}
 		let id = self.next_id();
 		let mut str = String::new();
-		writeln!(str, "// Anonymous struct").unwrap();
+		writeln!(str, "/// @dev anonymous struct").unwrap();
 		writeln!(str, "struct Tuple{} {{", id).unwrap();
 		for (i, name) in names.iter().enumerate() {
 			writeln!(str, "\t{} field_{};", name, i).unwrap();
@@ -416,12 +416,12 @@
 		tc: &TypeCollector,
 	) -> fmt::Result {
 		for doc in self.docs {
-			writeln!(writer, "\t//{}", doc)?;
+			writeln!(writer, "\t///{}", doc)?;
 		}
 		if !self.docs.is_empty() {
-			writeln!(writer, "\t//")?;
+			writeln!(writer, "\t///")?;
 		}
-		writeln!(writer, "\t// Selector: {}", self.selector)?;
+		writeln!(writer, "\t/// Selector: {}", self.selector)?;
 		write!(writer, "\tfunction {}(", self.name)?;
 		self.args.solidity_name(writer, tc)?;
 		write!(writer, ")")?;
@@ -498,7 +498,7 @@
 		if self.selector != ZERO_BYTES {
 			writeln!(
 				out,
-				"// Selector: {:0>8x}",
+				"/// @dev the ERC-165 identifier for this interface is 0x{:0>8x}",
 				u32::from_be_bytes(self.selector)
 			)?;
 		}
modifiedcrates/evm-coder/tests/generics.rsdiffbeforeafterboth
--- a/crates/evm-coder/tests/generics.rs
+++ b/crates/evm-coder/tests/generics.rs
@@ -19,14 +19,14 @@
 
 struct Generic<T>(PhantomData<T>);
 
-#[solidity_interface(name = "GenericIs")]
+#[solidity_interface(name = GenericIs)]
 impl<T> Generic<T> {
 	fn test_1(&self) -> Result<uint256> {
 		unreachable!()
 	}
 }
 
-#[solidity_interface(name = "Generic", is(GenericIs))]
+#[solidity_interface(name = Generic, is(GenericIs))]
 impl<T: Into<u32>> Generic<T> {
 	fn test_2(&self) -> Result<uint256> {
 		unreachable!()
@@ -35,7 +35,7 @@
 
 generate_stubgen!(gen_iface, GenericCall<()>, false);
 
-#[solidity_interface(name = "GenericWhere")]
+#[solidity_interface(name = GenericWhere)]
 impl<T> Generic<T>
 where
 	T: core::fmt::Debug,
modifiedcrates/evm-coder/tests/random.rsdiffbeforeafterboth
--- a/crates/evm-coder/tests/random.rs
+++ b/crates/evm-coder/tests/random.rs
@@ -21,14 +21,14 @@
 
 struct Impls;
 
-#[solidity_interface(name = "OurInterface")]
+#[solidity_interface(name = OurInterface)]
 impl Impls {
 	fn fn_a(&self, _input: uint256) -> Result<bool> {
 		unreachable!()
 	}
 }
 
-#[solidity_interface(name = "OurInterface1")]
+#[solidity_interface(name = OurInterface1)]
 impl Impls {
 	fn fn_b(&self, _input: uint128) -> Result<uint32> {
 		unreachable!()
@@ -48,7 +48,7 @@
 }
 
 #[solidity_interface(
-	name = "OurInterface2",
+	name = OurInterface2,
 	is(OurInterface),
 	inline_is(OurInterface1),
 	events(OurEvents)
@@ -79,3 +79,9 @@
 		unreachable!()
 	}
 }
+
+#[solidity_interface(
+	name = ValidSelector,
+	expect_selector = 0x00000000,
+)]
+impl Impls {}
modifiedcrates/evm-coder/tests/solidity_generation.rsdiffbeforeafterboth
--- a/crates/evm-coder/tests/solidity_generation.rs
+++ b/crates/evm-coder/tests/solidity_generation.rs
@@ -18,7 +18,7 @@
 
 struct ERC20;
 
-#[solidity_interface(name = "ERC20")]
+#[solidity_interface(name = ERC20)]
 impl ERC20 {
 	fn decimals(&self) -> Result<uint8> {
 		unreachable!()