Adding a payee to a donation contract. Error: Transaction reverted

Question

Disclaimer: I'm a noob when it comes to programming altogether let alone smart contracts.

I refactored this code that was written like three years ago so it could work with solidity 0.5.0. I deployed it on Remix's Javascript VM but the addPayee function is not working: transact to Donation.addPayee errored: VM error: revert. Please help thanks :(

Also, I'm not sure that the contract is assigning me (the deployer) as the owner.

contract Donation {


  address public owner;

  struct Payee {
    bool status;
    uint weight;
    uint balance;
  }

  e.
  mapping(address => Payee) public payees;
  mapping (int8 => address) public payeesIndex;

  int8 public payeesIndexSize;

  function Donations() private {
    // Set the address of the contract deployer to be owner.
    owner = msg.sender;
    payees[owner].status = true;
    payees[owner].weight = 10;
    payeesIndex[0] = owner;
    payeesIndexSize = 1;
  }

  // Check if current account calling methods is the owner.
  modifier isOwner() {

      require (msg.sender == owner);
    _;
  }

  // Aggregate all payee weights.
  function getTotalWeight() public view returns (uint) {

    int8 i;
    uint totalWeight = 0;

    for (i=0;i<payeesIndexSize;i++) {
       if (payees[payeesIndex[i]].status == true) {
         totalWeight += payees[payeesIndex[i]].weight;
       }
    }

    return totalWeight;
  }


  // Add a new payee to the contract.
  function addPayee(address _payee, uint _weight) isOwner public returns (bool) {

    payees[_payee].weight = _weight;
    payees[_payee].status = true;
    payeesIndex[payeesIndexSize] = _payee;
    payeesIndexSize++;

}

function getStatus(address _address) public view returns(bool)  {
    return payees[_address].status;
  }

Answer 1

function Donations() private {

This is not the same name as the contract, which would be the old style of constructor. If you rename to Donation(), the compiler will probably recognize you intend for this to be a constructor and warn you that the syntax should be changed to the new explicit form:

constructor() public {

There may be other issues, but your hunch is correct. It isn't setting owner to msg.sender on deployment, so that would make isOwner fail.

BTW, you can check owner() in Remix (because it is public) and you should see your sender address echoed back (usually 0x35c...), not 0x0000.... as it probably is presently. You will need that much to work as expected in order to press on for the next issue. ;-)

Hope it helps.

Update

This line:

payeesIndex[payeesIndexSize] = _payee

Should be payeesIndex.push(_payee);

Because you can't write past the end of a dynamic array.