Project #2: Basic Vault

Objective: multi-user safe

1. This is a single-token Vault that holds a pre-specified ERC-20 token.

2. Users can send tokens to the Vault contract.

3. Vault contract records the user's token deposits.

4. Users can withdraw their tokens only to the address they deposited from.

Contracts

• ERC20Mock.sol

• BasicVault.sol

Vault contract

1. Deposit: After approval (handled by front-end), token is deposited via transferFrom.

2. Withdraw: Token is returned, and the Vault updates its user records.

Vault contract should import the IERC20 interface, take the Token address in the Vault constructor, and cast it into an IERC20 state variable

ERC2Mock contract

1. Public, unrestricted mint() function: anyone should be able to mint

2. Import https://github.com/yieldprotocol/yield-utils-v2/blob/main/src/mocks/ERC20Mock.sol

3. Come up with your own fun token name

Additional Details

1. Add full NatSpec: the contract as well as every event and function should have complete NatSpec.

• contracts should have @title, @notice, @dev, @author.

• functions should have @notice, @dev, @param, @return.

• events should have @notice (no need param or return). https://docs.soliditylang.org/en/v0.5.10/natspec-format.html

1. Implement CI so when you push to gh, your tests are run automatically:

• https://gist.github.com/clifton/b5ee5286bb229281fb31d7c4b15e6f31
• https://book.getfoundry.sh/config/continous-integration.html

Testing

• Vault contract should be fully tested.

• No need to test ERC20Mock. Assume it works as intended.

Testing Guidelines

• All state variable changes in the contracts that you code.

• All state variable changes in other contracts caused by calls from contracts that you code.

• All require or revert in the contracts that you code.

• All events being emitted.

• All return values in contracts that you code.

Blueprint

contract BasicVault {
    
    // STATE VARS: 
    // token 
    // mapping to serve as balances registry
    // events 
    
    // constructor function
    
    // deposit function
    
    // withdraw function 

}