Staking 🏦

A simple ERC-20 staking contract for the Uniswap testnet I made to better understand the concept of staking.

Features

• A separate addLiquidity tasks to create/add to the Uniswap liquidity pool.
• All interfaces exposed in the ABI have a corresponding task in tasks/.
• All interfaces in the ABI are covered by NatSpec annotations.
• Includes tests which provide 100% coverage accoring to solidity-coverage.
• Deployment scripts are stored in scripts/.
• All private deployment data is stored using dotenv.
• The contract is deployed to the Rinkeby testnet @0x64739E615dD6DBE7E71285e8BA0A9Dd08bD09c3E.
• Additional verify task is made to easily verify the contract after deployment.
• Verified contract is available on Etherscan.

To do (21-05-2022)

• Refactor the contract to use struct and a mapping to store user data instead of 3 mappings.
• Add an additional require() in claim() to make sure that the user's balance is not 0.
• Add stakeEndTimestamp as another user variable.
• Update NatSpec and tasks/ in accordance with above changes.
• Add managerial tasks to change rewardPercentage, rewardInterval, and lockInterval.
• Test the deployed contract manually (all tasks) and get a new screenshot for demo.
• Configure tests to use Rinkeby fork locally.
• Configure solidity-coverage to use the aforementioned tests appropriately.
• Get done with the tests, add solidity_coverage 100% output to demo.
• Re-verify the contract and update the README.

Usage

IMPORTANT: all variable data needed to deploy/use/test the contract is stored in config.ts

cat config.ts
const config = {
  RINKEBY_ADDRESS: "0x64739E615dD6DBE7E71285e8BA0A9Dd08bD09c3E",
  ROUTER02_ADDRESS: "0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D",
  FACTORY_ADDRESS: "0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f",
  LIQUIDITY_TOKEN_ADDRESS: "0x676969756eA6417c8d35a29009F98Cf32758a433",
  TOKEN0_ADDRESS: "0xfAA8C0Beb910f8CF1a4F12Ef7848BA759550A9Ce",
  TOKEN1_ADDRESS: "0x146920e4384A60310e5499A4cb9A00B5C7c39feD",
  REWARD_PERCENTAGE: 10,
  REWARD_INTERVAL: 20,
  LOCK_INTERVAL: 40
};

export default config;

Contract follows a stake() → claim() → unstake() pattern.

0. Create or add to an existing liquidity pool to receive liquidity tokens:

hh addLiquidity --signer 0 --amount 200
Successfully added 200 of YAC and AYAC tokens to YAC/AYAC liquidity pool.
YAC tokens in YAC/AYAC liquidity pool: 100010010314
AYAC tokens in YAC/AYAC liquidity pool: 100010010314
Pair address: 0x676969756eA6417c8d35a29009F98Cf32758a433

1. Stake liquidity tokens:

hh stake --signer 0 --amount 100
0x9271EfD9709270334721f58f722DDc5C8Ee0E3DF staked 100 liquidity tokens.

2. After some time (which should be greater than LOCK_INTERVAL) claim the reward in reward tokens:

hh claim --signer 0
0x9271EfD9709270334721f58f722DDc5C8Ee0E3DF claimed 40 reward tokens.

3. Unstake liquidity tokens:

hh unstake --signer 0
0x9271EfD9709270334721f58f722DDc5C8Ee0E3DF unstaked 100 liquidity tokens.

Repeat as many times as you'd like to :)

P.S. hh is an alias for npx hardhat.

Demonstration