Foundry

Foundry is a blazing fast, portable and modular toolkit for Ethereum application development written in Rust.

Foundry consists of:

• Forge: Ethereum testing framework (like Truffle, Hardhat and DappTools).
• Cast: Swiss army knife for interacting with EVM smart contracts, sending transactions and getting chain data.
• Anvil: Local Ethereum node, akin to Ganache, Hardhat Network.
• Chisel: Fast, utilitarian, and verbose solidity REPL.

Documentation

https://book.getfoundry.sh/

Usage

Build

$ forge build

Test

$ forge test

Format

$ forge fmt

Gas Snapshots

$ forge snapshot

Anvil

$ anvil

Deploy

$ forge script script/Counter.s.sol:CounterScript --rpc-url <your_rpc_url> --private-key <your_private_key>

Cast

$ cast <subcommand>

Help

$ forge --help
$ anvil --help
$ cast --help

Layout of contract

version
imports
errors
interfaces, libraries, contracts
Type declarations
State variables
Events
Modifiers
Functions

Layout of Functions:

constructor
receive function (if exists)
fallback function (if exists)
external
public
internal
private
view & pure functions

CEI: Checks, Effects, Interactions Pattern

Checks: Requires, conditionals. It's gas efficient to revert early.

Effects: Internal contract state updates

* Calling `emit` is considered somethimes as part of Interactions but as best practice is better to set it on
Effects section. It might happen that the interaction changes a storage variable so the emited value is not 
correct at the end.

Interactions: External contract interactions