Capping the minting process can be simplified

[cleanunicorn]

Description

When the HaloToken is deployed, there are 2 state variables set:

https://github.com/monoceros-alpha/review-halodao-rewards-2021-06/blob/4757f51facd18a0fa205ffd9961df8c6b0409deb/code/contracts/HaloToken.sol#L24-L25

The canMint state variable is checked when the owner tries to mint additional tokens.

https://github.com/monoceros-alpha/review-halodao-rewards-2021-06/blob/4757f51facd18a0fa205ffd9961df8c6b0409deb/code/contracts/HaloToken.sol#L40-L41

The owner can renounce this power by calling setCapped.

https://github.com/monoceros-alpha/review-halodao-rewards-2021-06/blob/4757f51facd18a0fa205ffd9961df8c6b0409deb/code/contracts/HaloToken.sol#L28-L30

When setCapped is called, the state variable isCappedFuncLocked is checked to be false.

https://github.com/monoceros-alpha/review-halodao-rewards-2021-06/blob/4757f51facd18a0fa205ffd9961df8c6b0409deb/code/contracts/HaloToken.sol#L31

Once the check passes, canMint is set to false, blocking future token minting.

https://github.com/monoceros-alpha/review-halodao-rewards-2021-06/blob/4757f51facd18a0fa205ffd9961df8c6b0409deb/code/contracts/HaloToken.sol#L32

And isCappedFuncLocked is set to true; this prevents a second call to setCapped.

However, the 2 state variables are always synchronized. They can have the value true or false. And they only exist in these 2 states:

1. Can mint tokens; can disable token minting

canMint = true
isCappedFuncLocked = false

2. Cannot mint tokens anymore; cannot re-enable token minting

canMint = false
isCappedFuncLocked = true

The code can be simplified if one of the 2 state variables is removed, the other one's value can be deduced by negating the remaining one.

Recommendation

Remove isCappedFuncLocked and use canMint to limit the setCapped execution.