ethers-rs/ethers-core/src/abi/tokens.rs

552 lines
18 KiB
Rust

//! Contract Functions Output types.
// Adapted from: [rust-web3](https://github.com/tomusdrw/rust-web3/blob/master/src/contract/tokens.rs)
#![allow(clippy::all)]
use crate::{
abi::Token,
types::{Address, Bytes, H256, I256, U128, U256},
};
use arrayvec::ArrayVec;
use thiserror::Error;
#[derive(Clone, Debug, Error)]
#[error("{0}")]
pub struct InvalidOutputType(pub String);
/// Output type possible to deserialize from Contract ABI
pub trait Detokenize {
/// Creates a new instance from parsed ABI tokens.
fn from_tokens(tokens: Vec<Token>) -> Result<Self, InvalidOutputType>
where
Self: Sized;
}
impl Detokenize for () {
fn from_tokens(_: Vec<Token>) -> std::result::Result<Self, InvalidOutputType>
where
Self: Sized,
{
Ok(())
}
}
impl<T: Tokenizable> Detokenize for T {
fn from_tokens(mut tokens: Vec<Token>) -> Result<Self, InvalidOutputType> {
let token = match tokens.len() {
0 => Token::Tuple(vec![]),
1 => tokens.remove(0),
_ => Token::Tuple(tokens),
};
Self::from_token(token)
}
}
/// Tokens conversion trait
pub trait Tokenize {
/// Convert to list of tokens
fn into_tokens(self) -> Vec<Token>;
}
impl<'a> Tokenize for &'a [Token] {
fn into_tokens(self) -> Vec<Token> {
flatten_tokens(self.to_vec())
}
}
impl<T: Tokenizable> Tokenize for T {
fn into_tokens(self) -> Vec<Token> {
flatten_tokens(vec![self.into_token()])
}
}
impl Tokenize for () {
fn into_tokens(self) -> Vec<Token> {
vec![]
}
}
/// Simplified output type for single value.
pub trait Tokenizable {
/// Converts a `Token` into expected type.
fn from_token(token: Token) -> Result<Self, InvalidOutputType>
where
Self: Sized;
/// Converts a specified type back into token.
fn into_token(self) -> Token;
}
macro_rules! impl_tuples {
($num: expr, $( $ty: ident : $no: tt, )+) => {
impl<$($ty, )+> Tokenizable for ($($ty,)+) where
$(
$ty: Tokenizable,
)+
{
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Tuple(mut tokens) => {
let mut it = tokens.drain(..);
Ok(($(
$ty::from_token(it.next().expect("All elements are in vector; qed"))?,
)+))
},
other => Err(InvalidOutputType(format!(
"Expected `Tuple`, got {:?}",
other,
))),
}
}
fn into_token(self) -> Token {
Token::Tuple(vec![
$( self.$no.into_token(), )+
])
}
}
}
}
impl_tuples!(1, A:0, );
impl_tuples!(2, A:0, B:1, );
impl_tuples!(3, A:0, B:1, C:2, );
impl_tuples!(4, A:0, B:1, C:2, D:3, );
impl_tuples!(5, A:0, B:1, C:2, D:3, E:4, );
impl_tuples!(6, A:0, B:1, C:2, D:3, E:4, F:5, );
impl_tuples!(7, A:0, B:1, C:2, D:3, E:4, F:5, G:6, );
impl_tuples!(8, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, );
impl_tuples!(9, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, );
impl_tuples!(10, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, );
impl_tuples!(11, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, K:10, );
impl_tuples!(12, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, K:10, L:11, );
impl_tuples!(13, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, K:10, L:11, M:12, );
impl_tuples!(14, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, K:10, L:11, M:12, N:13, );
impl_tuples!(15, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, K:10, L:11, M:12, N:13, O:14, );
impl_tuples!(16, A:0, B:1, C:2, D:3, E:4, F:5, G:6, H:7, I:8, J:9, K:10, L:11, M:12, N:13, O:14, P:15, );
impl Tokenizable for Token {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
Ok(token)
}
fn into_token(self) -> Token {
self
}
}
impl Tokenizable for String {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::String(s) => Ok(s),
other => Err(InvalidOutputType(format!("Expected `String`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::String(self)
}
}
impl Tokenizable for Bytes {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Bytes(s) => Ok(s.into()),
other => Err(InvalidOutputType(format!("Expected `Bytes`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::Bytes(self.to_vec())
}
}
impl Tokenizable for H256 {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::FixedBytes(mut s) => {
if s.len() != 32 {
return Err(InvalidOutputType(format!("Expected `H256`, got {:?}", s)))
}
let mut data = [0; 32];
for (idx, val) in s.drain(..).enumerate() {
data[idx] = val;
}
Ok(data.into())
}
other => Err(InvalidOutputType(format!("Expected `H256`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::FixedBytes(self.as_ref().to_vec())
}
}
impl Tokenizable for Address {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Address(data) => Ok(data),
other => Err(InvalidOutputType(format!("Expected `Address`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::Address(self)
}
}
macro_rules! eth_uint_tokenizable {
($uint: ident, $name: expr) => {
impl Tokenizable for $uint {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Int(data) | Token::Uint(data) => {
Ok(::std::convert::TryInto::try_into(data).unwrap())
}
other => {
Err(InvalidOutputType(format!("Expected `{}`, got {:?}", $name, other))
.into())
}
}
}
fn into_token(self) -> Token {
Token::Uint(self.into())
}
}
};
}
eth_uint_tokenizable!(U256, "U256");
eth_uint_tokenizable!(U128, "U128");
macro_rules! int_tokenizable {
($int: ident, $token: ident) => {
impl Tokenizable for $int {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Int(data) | Token::Uint(data) => Ok(data.low_u128() as _),
other => Err(InvalidOutputType(format!(
"Expected `{}`, got {:?}",
stringify!($int),
other
))),
}
}
fn into_token(self) -> Token {
// this should get optimized away by the compiler for unsigned integers
#[allow(unused_comparisons)]
let data = if self < 0 {
// NOTE: Rust does sign extension when converting from a
// signed integer to an unsigned integer, so:
// `-1u8 as u128 == u128::max_value()`
U256::from(self as u128) | U256([0, 0, u64::max_value(), u64::max_value()])
} else {
self.into()
};
Token::$token(data)
}
}
};
}
int_tokenizable!(i8, Int);
int_tokenizable!(i16, Int);
int_tokenizable!(i32, Int);
int_tokenizable!(i64, Int);
int_tokenizable!(i128, Int);
int_tokenizable!(u8, Uint);
int_tokenizable!(u16, Uint);
int_tokenizable!(u32, Uint);
int_tokenizable!(u64, Uint);
int_tokenizable!(u128, Uint);
impl Tokenizable for bool {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Bool(data) => Ok(data),
other => Err(InvalidOutputType(format!("Expected `bool`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::Bool(self)
}
}
/// Marker trait for `Tokenizable` types that are can tokenized to and from a
/// `Token::Array` and `Token:FixedArray`.
pub trait TokenizableItem: Tokenizable {}
macro_rules! tokenizable_item {
($($type: ty,)*) => {
$(
impl TokenizableItem for $type {}
)*
};
}
tokenizable_item! {
Token, String, Address, H256, U256, I256, U128, bool, Vec<u8>,
i8, i16, i32, i64, i128, u16, u32, u64, u128, Bytes,
}
macro_rules! impl_tokenizable_item_tuple {
($( $ty: ident , )+) => {
impl<$($ty, )+> TokenizableItem for ($($ty,)+) where
$(
$ty: Tokenizable,
)+
{}
}
}
impl_tokenizable_item_tuple!(A,);
impl_tokenizable_item_tuple!(A, B,);
impl_tokenizable_item_tuple!(A, B, C,);
impl_tokenizable_item_tuple!(A, B, C, D,);
impl_tokenizable_item_tuple!(A, B, C, D, E,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J, K,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J, K, L,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J, K, L, M,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J, K, L, M, N,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O,);
impl_tokenizable_item_tuple!(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P,);
impl Tokenizable for Vec<u8> {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::Bytes(data) => Ok(data),
Token::Array(data) => data.into_iter().map(u8::from_token).collect(),
Token::FixedBytes(data) => Ok(data),
other => Err(InvalidOutputType(format!("Expected `bytes`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::Array(self.into_iter().map(Tokenizable::into_token).collect())
}
}
impl<T: TokenizableItem> Tokenizable for Vec<T> {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::FixedArray(tokens) | Token::Array(tokens) => {
tokens.into_iter().map(Tokenizable::from_token).collect()
}
other => Err(InvalidOutputType(format!("Expected `Array`, got {:?}", other))),
}
}
fn into_token(self) -> Token {
Token::Array(self.into_iter().map(Tokenizable::into_token).collect())
}
}
impl<T: TokenizableItem> TokenizableItem for Vec<T> {}
impl<const N: usize> Tokenizable for [u8; N] {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::FixedBytes(bytes) => {
if bytes.len() != N {
return Err(InvalidOutputType(format!(
"Expected `FixedBytes({})`, got FixedBytes({})",
N,
bytes.len()
)))
}
let mut arr = [0; N];
arr.copy_from_slice(&bytes);
Ok(arr)
}
other => {
Err(InvalidOutputType(format!("Expected `FixedBytes({})`, got {:?}", N, other))
.into())
}
}
}
fn into_token(self) -> Token {
Token::FixedBytes(self.to_vec())
}
}
impl<const N: usize> TokenizableItem for [u8; N] {}
impl<T: TokenizableItem + Clone, const N: usize> Tokenizable for [T; N] {
fn from_token(token: Token) -> Result<Self, InvalidOutputType> {
match token {
Token::FixedArray(tokens) => {
if tokens.len() != N {
return Err(InvalidOutputType(format!(
"Expected `FixedArray({})`, got FixedArray({})",
N,
tokens.len()
)))
}
let mut arr = ArrayVec::<T, N>::new();
let mut it = tokens.into_iter().map(T::from_token);
for _ in 0..N {
arr.push(it.next().expect("Length validated in guard; qed")?);
}
// Can't use expect here because [T; N]: Debug is not satisfied.
match arr.into_inner() {
Ok(arr) => Ok(arr),
Err(_) => panic!("All elements inserted so the array is full; qed"),
}
}
other => {
Err(InvalidOutputType(format!("Expected `FixedArray({})`, got {:?}", N, other))
.into())
}
}
}
fn into_token(self) -> Token {
Token::FixedArray(ArrayVec::from(self).into_iter().map(T::into_token).collect())
}
}
impl<T: TokenizableItem + Clone, const N: usize> TokenizableItem for [T; N] {}
/// Helper for flattening non-nested tokens into their inner
/// types, e.g. (A, B, C ) would get tokenized to Tuple([A, B, C])
/// when in fact we need [A, B, C].
fn flatten_tokens(mut tokens: Vec<Token>) -> Vec<Token> {
if tokens.len() == 1 {
// flatten the tokens if required
// and there is no nesting
match tokens.remove(0) {
Token::Tuple(inner) => inner,
other => vec![other],
}
} else {
tokens
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::types::{Address, U256};
use ethabi::Token;
fn output<R: Detokenize>() -> R {
unimplemented!()
}
#[test]
#[ignore]
fn should_be_able_to_compile() {
let _tokens: Vec<Token> = output();
let _uint: U256 = output();
let _address: Address = output();
let _string: String = output();
let _bool: bool = output();
let _bytes: Vec<u8> = output();
let _pair: (U256, bool) = output();
let _vec: Vec<U256> = output();
let _array: [U256; 4] = output();
let _bytes: Vec<[[u8; 1]; 64]> = output();
let _mixed: (Vec<Vec<u8>>, [U256; 4], Vec<U256>, U256) = output();
let _ints: (i16, i32, i64, i128) = output();
let _uints: (u16, u32, u64, u128) = output();
let _tuple: (Address, Vec<Vec<u8>>) = output();
let _vec_of_tuple: Vec<(Address, String)> = output();
let _vec_of_tuple_5: Vec<(Address, Vec<Vec<u8>>, String, U256, bool)> = output();
}
#[test]
fn nested_tokenization() {
let x = (1u64, (2u64, 3u64));
let tokens = x.into_tokens();
assert_eq!(
tokens,
vec![
Token::Uint(1.into()),
Token::Tuple(vec![Token::Uint(2.into()), Token::Uint(3.into())])
]
);
let x = (1u64, 2u64);
let tokens = x.into_tokens();
assert_eq!(tokens, vec![Token::Uint(1.into()), Token::Uint(2.into()),]);
}
#[test]
fn should_decode_array_of_fixed_bytes() {
// byte[8][]
let tokens = vec![Token::FixedArray(vec![
Token::FixedBytes(vec![1]),
Token::FixedBytes(vec![2]),
Token::FixedBytes(vec![3]),
Token::FixedBytes(vec![4]),
Token::FixedBytes(vec![5]),
Token::FixedBytes(vec![6]),
Token::FixedBytes(vec![7]),
Token::FixedBytes(vec![8]),
])];
let data: [[u8; 1]; 8] = Detokenize::from_tokens(tokens).unwrap();
assert_eq!(data[0][0], 1);
assert_eq!(data[1][0], 2);
assert_eq!(data[2][0], 3);
assert_eq!(data[7][0], 8);
}
#[test]
fn should_sign_extend_negative_integers() {
assert_eq!((-1i8).into_token(), Token::Int(U256::MAX));
assert_eq!((-2i16).into_token(), Token::Int(U256::MAX - 1));
assert_eq!((-3i32).into_token(), Token::Int(U256::MAX - 2));
assert_eq!((-4i64).into_token(), Token::Int(U256::MAX - 3));
assert_eq!((-5i128).into_token(), Token::Int(U256::MAX - 4));
}
#[test]
fn should_detokenize() {
// handle tuple of one element
let tokens = vec![Token::FixedBytes(vec![1, 2, 3, 4]), Token::Bool(true)];
let tokens = vec![Token::Tuple(tokens)];
let data: ([u8; 4], bool) = Detokenize::from_tokens(tokens).unwrap();
assert_eq!(data.0[0], 1);
assert_eq!(data.0[1], 2);
assert_eq!(data.0[2], 3);
assert_eq!(data.0[3], 4);
assert_eq!(data.1, true);
// handle vector of more than one elements
let tokens = vec![Token::Bool(false), Token::Uint(U256::from(13u8))];
let data: (bool, u8) = Detokenize::from_tokens(tokens).unwrap();
assert_eq!(data.0, false);
assert_eq!(data.1, 13u8);
// handle more than two tuples
let tokens1 = vec![Token::FixedBytes(vec![1, 2, 3, 4]), Token::Bool(true)];
let tokens2 = vec![Token::Bool(false), Token::Uint(U256::from(13u8))];
let tokens = vec![Token::Tuple(tokens1), Token::Tuple(tokens2)];
let data: (([u8; 4], bool), (bool, u8)) = Detokenize::from_tokens(tokens).unwrap();
assert_eq!((data.0).0[0], 1);
assert_eq!((data.0).0[1], 2);
assert_eq!((data.0).0[2], 3);
assert_eq!((data.0).0[3], 4);
assert_eq!((data.0).1, true);
assert_eq!((data.1).0, false);
assert_eq!((data.1).1, 13u8);
// error if no tokens in the vector
let tokens = vec![];
let data: Result<U256, InvalidOutputType> = Detokenize::from_tokens(tokens);
assert!(data.is_err());
}
}