Test/demeter balancer

[bayou020]

Added BaseFarm Test cases

[notion-workspace]

Testing

[parv3213]

Not related to this PR, but

• https://github.com/Sperax/Demeter-Protocol/blob/test/demeter-balancer/contracts/FarmFactory.sol#L25C1-L25C1
• https://github.com/Sperax/Demeter-Protocol/blob/test/demeter-balancer/contracts/FarmFactory.sol#L26
  variable can be made internal.

[parv3213]

Commendable work @bayou020 👏 .
Here are some points for improvement:

1. Better test cases for checking the math. Such as on deposit check math for _subscribeRewardFund, _updateFarmRewardData.
2. Tests for all functions of BaseFarms. Ex, after deposit check token balance before and after, or tests for IERC20(farmToken).safeTransferFrom(msg.sender, address(this), _amount);, or tests for recoverERC20, or checking math for _updateSubscriptionForIncrease.
3. Tests on demeter-farm (last level). For ex, tests for FARM_ID.
4. Tests for edge cases. This can be observed by looking at the coverage report.
5. This is unimportant, but the test function names can be improved by setting a standard. Like how do we want to deal with fuzz, revert, etc.
6. Right params for vm.expectEmit

[arcantheon]

Please resolve the comments