error de prueba de trufa variables globales no escritas

Contrato:

contract owned {
    function owned() public { owner = msg.sender; }
    address owner;

    modifier onlyOwner {
        require(msg.sender == owner);
        _;
    }
}

contract TestcontractCrowdSale is owned {
    uint public tokens_total = 0;

    struct holder {
        uint tokens_bonus_balance;
        uint tokens_all_balance;
        bool tokens_bonus_canspent;
        uint ethers_crowdfunded;
        uint list_pointer;
    }

    mapping (address => holder) public holders;
    address[] public holdersList;

    mapping (address => mapping (address => uint256)) public allowed;

    function checkIsHolder(address holderAddress) public constant returns (bool isIndeed) {
        if(holdersList.length == 0) return false;
        return (holdersList[holders[holderAddress].list_pointer] == holderAddress);
    }

    function getHoldersCount() public constant returns(uint count) {
        return holdersList.length;
    }

    function newHolder(address holderAddress) public returns(bool success) {
        if (!checkIsHolder(holderAddress)) {
            /*holders[holderAddress] = holder({
                tokens_bonus_balance: 0, 
                tokens_all_balance: 0,
                tokens_bonus_canspent : false,
                ethers_crowdfunded : 0,
                list_pointer : holdersList.push(holderAddress) - 1 
            });*/
            holders[holderAddress].list_pointer = holdersList.push(holderAddress) - 1;
        }
        return true;
    }

    function balanceOf(address tokenOwner) public view returns (uint balance) {
        return holders[tokenOwner].tokens_all_balance;
    }

    function preprint(address _for, uint tokens) onlyOwner public returns (bool printed, address __for, uint bonus_all_tokens) {
        newHolder(_for);
        holders[_for].tokens_all_balance += tokens;
        holders[_for].tokens_bonus_balance += tokens;
        holders[_for].tokens_bonus_canspent = false;
        tokens_total += tokens;
        return (true, _for, holders[_for].tokens_bonus_balance );
    }
}

---

truffle.cmd develop

truffle(develop)> compile
truffle(develop)> migrate

truffle(develop)> TestcontractCrowdSale.deployed().then((instance) => {contract = instance});

truffle(develop)> contract.preprint.call("0xC5fdf4076b8F3A5357c5E395ab970B5B54098Fef","123456",{ from: "0x627306090abaB3A6e1400e9345bC60c78a8BEf57"})
[ true,
  '0xc5fdf4076b8f3a5357c5e395ab970b5b54098fef',
  BigNumber { s: 1, e: 5, c: [ 123456 ] } ]
truffle(develop)> contract.preprint.call("0xC5fdf4076b8F3A5357c5E395ab970B5B54098Fef","123456",{ from: "0x627306090abaB3A6e1400e9345bC60c78a8BEf57"})
[ true,
  '0xc5fdf4076b8f3a5357c5e395ab970b5b54098fef',
  BigNumber { s: 1, e: 5, c: [ 123456 ] } ]
truffle(develop)> contract.balanceOf("0xC5fdf4076b8F3A5357c5E395ab970B5B54098Fef")
BigNumber { s: 1, e: 0, c: [ 0 ] }
truffle(develop)> contract.tokens_total()
BigNumber { s: 1, e: 0, c: [ 0 ] }
truffle(develop)> contract.tokens_total.call()
BigNumber { s: 1, e: 0, c: [ 0 ] }

---

Pero en remix todo funciona bien, la función de preimpresión funciona bien y no puedo entender, ¿por qué? ¡El contrato es el mismo!

Eso es un gran problema para mí.