1. ethers 6
2. ethers.BigNumber -> bigint
3. mock.addConsumer(subId, raffle)
4. sol里用不到的参数, hardhat里怎么传? "0x" empty bytes
5. verify:verify. 访问sepolia 需要代理 http_proxy="http://localhost:1087" hh deploy --network sepolia
6. running "hardhat test", deployments.log doesn't show => console.log
7. 使用VRFCoordinatorV2_5Mock 代替 使用VRFCoordinatorV2Mock, 多了构造参数WeiPerUnitLink, 调用fulfillRandomWords的费用计算, 如果不是nativebalance, 使用了这个参数
8. vrf address on sepolia differs. chainlink debugging with tenderly. solidity import "hardhat/console"

????

• always import describe from "node:test" automatically
• chai.expect, how to test the event and get the result for the next test step at the same time?
• staticCall ?
• listener? raffle.once()
• payable(msg.sender) sol => string hardhat ?
• 合约自动转出的钱 没有gas?
• hre.deployments.deploy => ? .address vs ethers.getContract() => BaseContract.getAddress()
• 临时修改类型uint64->uint256 and cast back using a VRFv2Consumer.sol with a VRF 2.5 subscription #todo: upgrade
• when running "hardhat test", no deployment logs show?
• custom verification on localhost
• hh deploy: if "verify" fails(network error), re-runing "hh deploy" will continue, won't re-deploy. ?
• 部署修改后再次部署, 新地址. ethers.getContract 获取最新的?
• 链上debug?

for typescript:

• yarn add typescript ts-node typechain @typechain/ethers-v6 @typechain/hardhat @types/mocha
• hh typechain, generate typechain-types directory
• raffle.once: first argument now is raffle.filters.RaffleWinnerPicked, not string