Issue with solidity contract mapping

Question

Hi I am trying to do a call between my solidity contract and js file.

I have a contract Im providing a portion of:

   struct Player {
    uint wins;
    uint losses;
}

mapping (address => Player) public players;

function gameStart(uint display, bool guess) external payable returns (bool, uint) {
  
    uint Number = numberToGuess();
    bool isWinner = whoWins(Number, display, guess);
    if (isWinner == true) {
        players[msg.sender].wins += 5;
        msg.sender.transfer(msg.value);
        return (true, Number);

    } else if (isWinner == false) {
        players[msg.sender].losses += 5;         
        return (false, Number);
    }
}

This is then contacting to my js file:

    it('Record losses', async () => {
  const initialStats = await gaming.players(player1);
  console.log('Initial Player Stats:', initialStats);

  const gameRound = await gaming.gameStart(20, true, {
    from: player1,
    value: web3.utils.toWei('0.01', 'ether')
  });

  const postStats = await gaming.players(player1);
  console.log('Post Player Stats:', postStats);

  assert.equal(postStats[1].toNumber(), 1, 'The player should lose');
});

  it('Record wins', async() => {
    const gameRound = await gaming.gameStart(20, false, {
      from: player1,
      value: web3.utils.toWei('0.01', 'ether')
    })
    const playerStats = await gaming.players(player1)
    assert.equal(playerStats[0].toNumber(), 1, 'The player should win')
  })
})

The 'Record Wins' is successful, but 'Record losses' is failing, with the 'The player should win' assert. I can see my wins are recorded but losses are not. Wondering what the issue is?

Answer 1

I think you're trying to access player stats using incorrect indexes.

Solution:

• players[msg.sender].wins represents the number of wins for the player with the address msg.sender.
• players[msg.sender].losses represents the number of losses for the player with the address msg.sender.

Corrected code:

assert.equal(postStats.losses.toNumber(), 1, 'The player should lose');
assert.equal(playerStats.wins.toNumber(), 1, 'The player should win');

Note: players[msg.sender] returns a Player struct, not an array. You can access its properties directly using dot notation.