This release introduces new features and fixes to the Stylus SDK. We've bumped the major version number due to minor backwards-incompatible changes. To adopt the latest version, edit your Cargo.toml as follows

stylus-sdk = "0.4.1"

Check if address has code

The AddressVM trait from the prelude has a new method, has_code, for detecting if an account has code.

use stylus-sdk::{prelude::*, contract, alloy_primitives::address};

let arbinaut = address!(361594F5429D23ECE0A88E4fBE529E1c49D524d8);
assert!(!arbinaut.has_code());
assert!(contract::address().has_code())

Note that this is insufficient to determine if an address is an EOA. During contract deployment, an account only gets its code at the very end, meaning that this method will return false while the constructor is executing.

As part of this change, we've updated the method signature of Address::codehash to return a B256 instead of an Option. Previously the Option was supposed to be None if the account was not a contract. Splitting this out into two methods is a more sensible API.

Configurable Selectors

You may now override method selectors.

impl Contract {
    #[selector(name = "otherName")]
    pub fn renamed() {
        ...
    }
    
    #[selector(id = "otherFunc(uint64)")]
    pub fn other_selector(value: U64) {
        ...
    }
    
    #[selector(id = 0xba5eba11)]
    pub fn exact_selector() {
        ...
    }
}

The above will now export

/**
 * This file was automatically generated by Stylus and represents a Rust program.
 * For more information, please see [The Stylus SDK](https://github.com/OffchainLabs/stylus-sdk-rs).
 */
 
interface IContract {
        function otherName() external pure;

        // note: selector was overridden to be 0x7cc01843.
        function otherSelector(uint64 value) external pure;

        // note: selector was overridden to be 0xba5eba11.
        function exactSelector() external pure;
}

Reentrancy Changes

Because Call::new is never correct in reentrant code, the reentrant feature flag removes it. This shouldn't affect existing contracts since reentrant calls instead use Call::new_in.