Foundry Projects

This repositiry contains the projects from Cyfrin Foundry Course

Projects

Foundry intro

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: Command line tool 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.

Basic 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>
### Remapping
forge remappings > remappings.txt
### Test chain
anvil

Step by step project development

Creating project

Create project forge init
Build the project forge build
Add anvil network and account to metamask anvil
Write the SimpleStorage.sol
Deploy contract forge create SimpleStorage --private-key KEY
Remove private key from your history in Bash history -c. Others rm .bash_history .zsh_history

Deploying using script

Write deployment script SimpleStorage.s.sol. It should inherite Script from forge-std/Script.sol and have setUp() and run() functions
Run the script forge script script/SimpleStorage.s.sol
Deploying on anvil forge script script/SimpleStorage.s.sol --rpc-url http://127.0.0.1:8545 --broadcast --private-key KEY
A new broadcast folder will be created. Check run-latest.json file
The transaction is sent to blockchain, value is the eth amount stored, data is the code, nonce is the counter of how many times the same transaction is deployed.
To convert a hex to decimal like "gas": "0x6b0d2", run cast to-dec 0x6b0d2
Don't use .env to store private key, use cast wallet import the-key --interactive
See the private keys cast wallet list
New script command forge script script/SimpleStorage.s.sol --rpc-url http://127.0.0.1:8545 --broadcast --account KEY_NAME --sender ACCOUNT_ADDRESS -vvvv

Interecting with the smart contract

setMyNumber cast send CONTRACT_ADDRESS "setMyNumber(uint256)" 12345 --rpc-url http://127.0.0.1:8545 --private-key KEY
getMyNumber cast call CONTRACT_ADDRESS "getMyNumber()" --rpc-url http://127.0.0.1:8545
Convert the hex to decimal cast to-dec HEX_CODE

Testing

Write a test script SimpleStorage.t.sol. It should inherite Test from forge-std/Test.sol and have setUp() and testMETHOD() functions
Run test forge test -vvvv
Run a specific test function forge test --match-test REGEX
Run a specific contract forge test --match-contract REGEX

Knowledge base

Calldata vs Memory

Aspect	Calldata	Memory
Mutability	Immutable	Mutable
Usage	Function arguments are passed through it	Used for temporary data storage and manipulation
Efficiency	Efficient for reading	Efficient for data manipulation
Modifiability	Cannot be modified	Can be modified during contract execution
Persistence	Data is not persistent	Data is not persistent
Clearing	N/A	Cleared between function calls
Size	Limited	Dynamic

Inheritence

To make a method overrideable make it virtual
A contract can inherite another using is operator
Add override modifier to the child contract method

Transfer vs Send vs Call

Feature	send	transfer	call
Syntax	`address.send(uint256 amount) returns (bool)`	`address.transfer(uint256 amount)`	`address.call{value: uint256}(bytes memory data) returns (bool, bytes memory)`
Gas Limit	2300 (only for logging)	2300 (only for logging)	All available gas or a specific amount
Error Handling	Returns `false` on failure	Throws an exception on failure	Returns a boolean value and allows access to returned data
Use Case	Low-level method for sending Ether, requires explicit failure handling	Automatically reverts on failure, used for simple Ether transfers	Flexible method for sending Ether and calling functions on contracts, requires explicit error handling
Security	Safer against reentrancy attacks due to gas limit	Safer against reentrancy attacks due to automatic revert on failure	Requires careful error handling to avoid security pitfalls like reentrancy attacks

imranpollob / foundry-cyfrin