(address[] memory tokens, , ) = balancerVault.getPoolTokens(poolId);

uint256 len = tokens.length;
token0 = (len > 0) ? tokens[1] : address(0);
token1 = (len > 1) ? tokens[2] : address(0);
token2 = (len > 2) ? tokens[3] : address(0);
function _getTokenPrice(uint256 index) internal view returns (uint256 price) {
  address token;
  if (index == 0) token = token0;
  else if (index == 1) token = token1;
  else if (index == 2) token = token2;
  else revert BalancerOracle__getTokenPrice_invalidIndex();

  return chainlinkOracle.spot(token);
}
