Trying to get array size but it reverts

Question

I wanted to get array length by getter function, but it keeps reverts. But I have no idea why it's reverting. Here is my code.

struct ItemAddress {
    uint8 sendNatCd;
    uint8 rcvNatCd;
    uint16 ordID;
    string sendAddr;
    string rcvAddr;
}

ItemAddress[] public itemAddresses;

function createItemAddress(
    uint16 _ordID,
    uint8 _sendNatCd,
    uint8 _rcvNatCd,
    string calldata _sendAddr,
    string calldata _rcvAddr
)
    external
    returns
(
    uint256 itemAddressID
)
{
    ItemAddress memory _itemAddress = ItemAddress({
        ordID: _ordID,
        sendNatCd: _sendNatCd,
        rcvNatCd: _rcvNatCd,
        sendAddr: _sendAddr,
        rcvAddr: _rcvAddr
    });

    itemAddressID = itemAddresses.push(_itemAddress) - 1;

    return itemAddressID;
}

function getItemAddress(uint16 id)
    external
    view
    returns
(
    uint16 _ordID,
    uint8 _sendNatCd,
    uint8 _rcvNatCd,
    string memory _sendAddr,
    string memory _rcvAddr
)
{
    ItemAddress storage itemAddress = itemAddresses[id];

    _ordID = itemAddress.ordID;
    _sendNatCd = itemAddress.sendNatCd;
    _rcvNatCd = itemAddress.rcvNatCd;
    _sendAddr = itemAddress.sendAddr;
    _rcvAddr = itemAddress.rcvAddr;
}

function getItemLength()
    public
    view
    returns (uint256)
{
    return itemAddresses.length;
}

When I push data to itemAddresses array with createItemAddress(), I can get the data with getItemAddress() (ex. getItemAddress(0)). But when I call getItemLength(), it keeps reverting. So I tried itemAddresses.length at truffle console, and it returned 0. I'm confused that I could receive data from getItemAddress(), but why the itemAddresses array length is zero. What did I do wrong here?

Answer 1

I'm also confused about what is wrong with your tests. I simplified the code a bit (removed variables from the struct) and tried in Remix - everything seems to work:

pragma solidity ^0.5.0; 

contract A {
    struct ItemAddress {
        uint16 ordID;
    }

    ItemAddress[] public itemAddresses;

    function createItemAddress(
        uint16 _ordID
    )
        external
        returns
    (
        uint256 itemAddressID
    )
    {
        ItemAddress memory _itemAddress = ItemAddress({
            ordID: _ordID
        });

        itemAddressID = itemAddresses.push(_itemAddress) - 1;

        return itemAddressID;
    }

    function getItemAddress(uint16 id)
        external
        view
        returns
    (
        uint16 _ordID
    )
    {
        ItemAddress storage itemAddress = itemAddresses[id];

        _ordID = itemAddress.ordID;
    }

    function getItemLength()
        public
        view
        returns (uint256)
    {
        return itemAddresses.length;
    }
}

I also tried with your original code and that works just as fine.