Solidity (Truffle): Works fine with truffle console, but fails with truffle test - solidity

Question

I'm running something with truffle console that works fine, but fails with truffle test.
The code is:
contract Geekt {
address[] usersByAddress;
function registerNewUser(string handle, bytes32 city, bytes32 state, bytes32 country) public returns (bool success) {
address newUserAddress = msg.sender;
usersByAddress.push(newUserAddress);
return true;
}
function getUsers() public constant returns (address[]) {
return usersByAddress;
}
}
And the tests are:
var Geekt = artifacts.require("Geekt");
contract('Geekt', function (accounts) {
it('should get initial users as empty array', function () {
return Geekt.deployed().then(function (instance) {
return instance.getUsers.call();
}).then(function (res) {
assert.equal(res.length, 0, "Expected empty array after init.");
});
});
it('should successfully add user', function () {
var geekt;
return Geekt.deployed().then(function (instance) {
geekt = instance;
return geekt.registerNewUser.call("elie222", "London", "State", "UK");
}).then(function (res) {
assert.equal(res, true, "Expected registerNewUser to return true.");
}).then(function (res) {
return geekt.getUsers.call();
}).then(function (res) {
// for debugging, but this assert passes: assert.equal(res.length, 0, "Expected array of size 0 after registerNewUser.");
// res == [] so the next line fails:
assert.equal(res.length, 1, "Expected array of size 1 after registerNewUser.");
});
});
});
It works great with truffle console:
truffle(development)> Geekt.then(function(instance){return instance.registerNewUser("Tectract","Denver","CO","USA");})
{ tx: '0x8eeea303ff9f5ceee56d71fd1265da61991749aa3d5e82db0d2d630a98fd6eb5',
receipt:
{ transactionHash: '0x8eeea303ff9f5ceee56d71fd1265da61991749aa3d5e82db0d2d630a98fd6eb5',
transactionIndex: 0,
blockHash: '0xf9a0da5ec0aba80a3338781f6d6414ceb43ec0fc023c31649a1cc347a4aba2ea',
blockNumber: 14,
gasUsed: 24566,
cumulativeGasUsed: 24566,
contractAddress: null,
logs: [] },
logs: [] }
truffle(development)> Geekt.then(function(instance){return instance.getUsers();})
[ '0x1a004a36a6bc9bcde42c6d2b237c6477cf0f535f' ]
How could this happen? What am I doing wrong?

Answer 1

The issue was that I was doing a call instead of a transaction.
Transactions change state whereas method calls do not and are only to read from the network.
You can read more about it here:
https://truffle.readthedocs.io/en/beta/getting_started/contracts/