Fetching total token supply

[pwollemi]

v2-subgraph/src/mappings/helpers.ts

Line 116 in 7c82235

export function fetchTokenTotalSupply(tokenAddress: Address): BigInt {

export function fetchTokenTotalSupply(tokenAddress: Address): BigInt {
  let contract = ERC20.bind(tokenAddress)
  let totalSupplyValue = null
  let totalSupplyResult = contract.try_totalSupply()
  if (!totalSupplyResult.reverted) {
    totalSupplyValue = totalSupplyResult as i32
  }
  return BigInt.fromI32(totalSupplyValue as i32)
}

In this function, if we convert the result to i32, then the upper field is cut I think.
Shouldn't it be like this?

export function fetchTokenTotalSupply(tokenAddress: Address): BigInt {
  let contract = ERC20.bind(tokenAddress)
  let totalSupplyValue = new BigInt(0)
  let totalSupplyResult = contract.try_totalSupply()
  if (!totalSupplyResult.reverted) {
    totalSupplyValue = totalSupplyResult.value
  }
  return totalSupplyValue;
}

If I am not recognizing the correct type of i32, pls tell me.
And may many know, does this function fetch the value from the latest block or the current scanning block?