herzogian / chess Goto Github PK

If a move causes check, and there's no way to get out of check, it is checkmate

• remove Chess-v0.0.1.tgz
• remove all files under js/lib other than 'validate.js', 'utilities.js', 'update.js' (all others are unused)

Find a better approach of ad-hoc unit testing. The current approach doesn't tell you if the move should succeed, only that it does. It's also painfully verbose per-test:

if (move('C4', 'E3')) {
    console.log('moved')
} else {
    console.log('move failed')
};

Firstly, throwing an Error when there's an error is good practice, and you don't really need to see that it's succeeded on every run, so something like this would be good:

if (!move('C4', 'E3')) {
  throw Error('[SHOULD_BE_VALID] moving C4 to E3 should be valid')
}

Think about how to run these tests in the DRYest way possible

can move/capture one square in any direction

• triggered by moving an unmoved king two squares towards an unmoved rook
• no pieces can be in the way
• the king cannot move through check (make sure no enemy pieces attack the intermediate square)

1. any move that results in the moving player's king being checked or remaining in check is invalid
2. any move that results in the non-moving player's king being placed in check records it in the game state
3. if a player is in check, they must move out of check (this is a special case of 1)

If a player is not in check, but has no legal moves, the game is a draw

Leave the full set of stalemate conditions for later

• Bishops and queens can move diagonally
• Rooks and queens can move horizontally and vertically
• cannot pass through pieces

• can move forward one empty square at a time
• can capture diagonally
• first move can be two squares
• can en passant

• triggers when a pawn reaches the opponents back rank
• the transform is specified by =Q appended to the target square notation
• the pawn is replaced with the selected piece

• move in a 2-to-1 L shape
• can jump other pieces