# Store Field - Record the Game Winner
In this section, you will:
- Check for a game winner.
- Extend unit tests.
To be able to terminate games, you need to discern between games that are current and those that have reached an end - for example, when they have been won. Therefore a good field to add is for the winner. It needs to contain:
- The winner of a game that reaches completion.
- Or the winner by forfeit when a game is expired.
- Or a neutral value when the game is active.
In this exercise a draw is not handled and it would require yet another value to save in winner.
# New information
StoredGame Protobuf definition file:
Have Ignite CLI and Protobuf recompile this file:
Add a helper function to get the winner's address, if it exists. A location is in
# Update and check for the winner
This is a two-part update. You set the winner where relevant, but you also introduce new checks so that a game with a winner cannot be acted upon.
Start with a new error that you define as a constant:
At creation, in the create game message handler, start with a neutral value:
With further checks when handling a play in the handler:
Check that the game has not finished yet:
Update the winner field, which remains neutral (opens new window) if there is no winner yet:
Handle the FIFO differently depending on whether the game is finished or not:
And when rejecting a game, in its handler:
Confirm the code compiles, add unit tests, and you are ready to handle the expiration of games.
# Unit tests
You need to update your existing tests so that they pass with a new
Winner value. Most of your tests need to add this line:
This means that in your tests no games have reached a conclusion with a winner. Time to fix that. In a dedicated
msg_server_play_move_winner_test.go file, prepare all the moves that will be played in the test. For convenience, a move will be written as:
If you do not want to create a complete game yourself, you can choose this one:
You may want to add a small function that converts
"r" into their respective player addresses:
Now create the test that plays all the moves, and checks at the end that the game has been saved with the right winner and that the FIFO is empty again:
Feel free to create another game won by the red player.
# Interact via the CLI
If you have created games in an earlier version of the code, you are now in a broken state. You cannot even play the old games because they have
.Winner == "" and this will be caught by the
if storedGame.Winner != rules.PieceStrings[rules.NO_PLAYER] test. Start again:
Do not forget to export
bob again, as explained in an earlier section.
Confirm that there is no winner for a game when it is created:
This should show:
And when a player plays:
This should show:
Testing with the CLI up to the point where the game is resolved with a rightful winner is better covered by unit tests or with a nice GUI. You will be able to partially test this in the next section, via a forfeit.