refactor: NCS-22 NCS-23 reworked modules and tests (#17)
Build & Test (NowChessSystems) TeamCity build finished

Reviewed-on: #17
This commit was merged in pull request #17.
This commit is contained in:
2026-04-06 09:07:39 +02:00
parent 51ffd7aac9
commit 8f56a82104
98 changed files with 3752 additions and 5940 deletions
+2 -10
View File
@@ -1,7 +1,6 @@
plugins {
id("scala")
id("org.scoverage") version "8.1"
application
}
group = "de.nowchess"
@@ -22,19 +21,10 @@ scoverage {
scoverageVersion.set(versions["SCOVERAGE"]!!)
}
application {
mainClass.set("de.nowchess.chess.Main")
}
tasks.withType<ScalaCompile> {
scalaCompileOptions.additionalParameters = listOf("-encoding", "UTF-8")
}
tasks.named<JavaExec>("run") {
jvmArgs("-Dfile.encoding=UTF-8", "-Dstdout.encoding=UTF-8", "-Dstderr.encoding=UTF-8")
standardInput = System.`in`
}
dependencies {
implementation("org.scala-lang:scala3-compiler_3") {
@@ -49,6 +39,8 @@ dependencies {
}
implementation(project(":modules:api"))
implementation(project(":modules:io"))
implementation(project(":modules:rule"))
testImplementation(platform("org.junit:junit-bom:5.13.4"))
testImplementation("org.junit.jupiter:junit-jupiter")
@@ -1,7 +1,7 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, Board, Color, Piece}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.api.board.{Square, Piece}
import de.nowchess.api.game.GameContext
/** Marker trait for all commands that can be executed and undone.
* Commands encapsulate user actions and game state transitions.
@@ -23,23 +23,22 @@ case class MoveCommand(
from: Square,
to: Square,
moveResult: Option[MoveResult] = None,
previousBoard: Option[Board] = None,
previousHistory: Option[GameHistory] = None,
previousTurn: Option[Color] = None
previousContext: Option[GameContext] = None,
notation: String = ""
) extends Command:
override def execute(): Boolean =
moveResult.isDefined
override def undo(): Boolean =
previousBoard.isDefined && previousHistory.isDefined && previousTurn.isDefined
previousContext.isDefined
override def description: String = s"Move from $from to $to"
// Sealed hierarchy of move outcomes (for tracking state changes)
sealed trait MoveResult
object MoveResult:
case class Successful(newBoard: Board, newHistory: GameHistory, newTurn: Color, captured: Option[Piece]) extends MoveResult
case class Successful(newContext: GameContext, captured: Option[Piece]) extends MoveResult
case object InvalidFormat extends MoveResult
case object InvalidMove extends MoveResult
@@ -51,14 +50,12 @@ case class QuitCommand() extends Command:
/** Command to reset the board to initial position. */
case class ResetCommand(
previousBoard: Option[Board] = None,
previousHistory: Option[GameHistory] = None,
previousTurn: Option[Color] = None
previousContext: Option[GameContext] = None
) extends Command:
override def execute(): Boolean = true
override def undo(): Boolean =
previousBoard.isDefined && previousHistory.isDefined && previousTurn.isDefined
previousContext.isDefined
override def description: String = "Reset board"
@@ -1,106 +0,0 @@
package de.nowchess.chess.controller
import de.nowchess.api.board.{Board, Color, File, Piece, PieceType, Rank, Square}
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.*
// ---------------------------------------------------------------------------
// Result ADT returned by the pure processMove function
// ---------------------------------------------------------------------------
sealed trait MoveResult
object MoveResult:
case object Quit extends MoveResult
case class InvalidFormat(raw: String) extends MoveResult
case object NoPiece extends MoveResult
case object WrongColor extends MoveResult
case object IllegalMove extends MoveResult
case class PromotionRequired(
from: Square,
to: Square,
boardBefore: Board,
historyBefore: GameHistory,
captured: Option[Piece],
turn: Color
) extends MoveResult
case class Moved(newBoard: Board, newHistory: GameHistory, captured: Option[Piece], newTurn: Color) extends MoveResult
case class MovedInCheck(newBoard: Board, newHistory: GameHistory, captured: Option[Piece], newTurn: Color) extends MoveResult
case class Checkmate(winner: Color) extends MoveResult
case object Stalemate extends MoveResult
// ---------------------------------------------------------------------------
// Controller
// ---------------------------------------------------------------------------
object GameController:
/** Pure function: interprets one raw input line against the current game context.
* Has no I/O side effects all output must be handled by the caller.
*/
def processMove(board: Board, history: GameHistory, turn: Color, raw: String): MoveResult =
raw.trim match
case "quit" | "q" => MoveResult.Quit
case trimmed =>
Parser.parseMove(trimmed) match
case None => MoveResult.InvalidFormat(trimmed)
case Some((from, to)) => validateAndApply(board, history, turn, from, to)
/** Apply a previously detected promotion move with the chosen piece.
* Called after processMove returned PromotionRequired.
*/
def completePromotion(
board: Board,
history: GameHistory,
from: Square,
to: Square,
piece: PromotionPiece,
turn: Color
): MoveResult =
val (boardAfterMove, captured) = board.withMove(from, to)
val promotedPieceType = piece match
case PromotionPiece.Queen => PieceType.Queen
case PromotionPiece.Rook => PieceType.Rook
case PromotionPiece.Bishop => PieceType.Bishop
case PromotionPiece.Knight => PieceType.Knight
val newBoard = boardAfterMove.updated(to, Piece(turn, promotedPieceType))
// Promotion is always a pawn move → clock resets
val newHistory = history.addMove(from, to, None, Some(piece), wasPawnMove = true)
toMoveResult(newBoard, newHistory, captured, turn)
// ---------------------------------------------------------------------------
// Private helpers
// ---------------------------------------------------------------------------
private def validateAndApply(board: Board, history: GameHistory, turn: Color, from: Square, to: Square): MoveResult =
board.pieceAt(from) match
case None => MoveResult.NoPiece
case Some(piece) if piece.color != turn => MoveResult.WrongColor
case Some(_) =>
if !GameRules.legalMoves(board, history, turn).contains(from -> to) then MoveResult.IllegalMove
else if MoveValidator.isPromotionMove(board, from, to) then
MoveResult.PromotionRequired(from, to, board, history, board.pieceAt(to), turn)
else applyNormalMove(board, history, turn, from, to)
private def applyNormalMove(board: Board, history: GameHistory, turn: Color, from: Square, to: Square): MoveResult =
val castleOpt = Option.when(MoveValidator.isCastle(board, from, to))(MoveValidator.castleSide(from, to))
val isEP = EnPassantCalculator.isEnPassant(board, history, from, to)
val (newBoard, captured) = castleOpt match
case Some(side) => (board.withCastle(turn, side), None)
case None =>
val (b, cap) = board.withMove(from, to)
if isEP then
val capturedSq = EnPassantCalculator.capturedPawnSquare(to, turn)
(b.removed(capturedSq), board.pieceAt(capturedSq))
else (b, cap)
val pieceType = board.pieceAt(from).map(_.pieceType).getOrElse(PieceType.Pawn)
val wasPawnMove = pieceType == PieceType.Pawn
val wasCapture = captured.isDefined
val newHistory = history.addMove(from, to, castleOpt, wasPawnMove = wasPawnMove, wasCapture = wasCapture, pieceType = pieceType)
toMoveResult(newBoard, newHistory, captured, turn)
private def toMoveResult(newBoard: Board, newHistory: GameHistory, captured: Option[Piece], turn: Color): MoveResult =
GameRules.gameStatus(newBoard, newHistory, turn.opposite) match
case PositionStatus.Normal => MoveResult.Moved(newBoard, newHistory, captured, turn.opposite)
case PositionStatus.InCheck => MoveResult.MovedInCheck(newBoard, newHistory, captured, turn.opposite)
case PositionStatus.Mated => MoveResult.Checkmate(turn)
case PositionStatus.Drawn => MoveResult.Stalemate
@@ -1,47 +1,37 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.{Board, Color, Piece, Square}
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{GameHistory, GameRules, PositionStatus}
import de.nowchess.chess.controller.{GameController, Parser, MoveResult}
import de.nowchess.api.board.{Board, Color, Piece, PieceType, Square}
import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
import de.nowchess.api.game.GameContext
import de.nowchess.chess.controller.Parser
import de.nowchess.chess.observer.*
import de.nowchess.chess.command.{CommandInvoker, MoveCommand}
import de.nowchess.chess.notation.{PgnExporter, PgnParser}
import de.nowchess.chess.command.{CommandInvoker, MoveCommand, MoveResult}
import de.nowchess.io.{GameContextImport, GameContextExport}
import de.nowchess.rules.RuleSet
import de.nowchess.rules.sets.DefaultRules
/** Pure game engine that manages game state and notifies observers of state changes.
* This class is the single source of truth for the game state.
* All user interactions must go through this engine via Commands, and all state changes
* are communicated to observers via GameEvent notifications.
* All rule queries delegate to the injected RuleSet.
* All user interactions go through Commands; state changes are broadcast via GameEvents.
*/
class GameEngine(
initialBoard: Board = Board.initial,
initialHistory: GameHistory = GameHistory.empty,
initialTurn: Color = Color.White,
completePromotionFn: (Board, GameHistory, Square, Square, PromotionPiece, Color) => MoveResult =
GameController.completePromotion
val initialContext: GameContext = GameContext.initial,
val ruleSet: RuleSet = DefaultRules
) extends Observable:
private var currentBoard: Board = initialBoard
private var currentHistory: GameHistory = initialHistory
private var currentTurn: Color = initialTurn
private var currentContext: GameContext = initialContext
private val invoker = new CommandInvoker()
/** Inner class for tracking pending promotion state */
private case class PendingPromotion(
from: Square, to: Square,
boardBefore: Board, historyBefore: GameHistory,
turn: Color
)
/** Current pending promotion, if any */
/** Pending promotion: the Move that triggered it (from/to only, moveType filled in later). */
private case class PendingPromotion(from: Square, to: Square, contextBefore: GameContext)
private var pendingPromotion: Option[PendingPromotion] = None
/** True if a pawn promotion move is pending and needs a piece choice. */
def isPendingPromotion: Boolean = synchronized { pendingPromotion.isDefined }
// Synchronized accessors for current state
def board: Board = synchronized { currentBoard }
def history: GameHistory = synchronized { currentHistory }
def turn: Color = synchronized { currentTurn }
def board: Board = synchronized { currentContext.board }
def turn: Color = synchronized { currentContext.turn }
def context: GameContext = synchronized { currentContext }
/** Check if undo is available. */
def canUndo: Boolean = synchronized { invoker.canUndo }
@@ -59,7 +49,6 @@ class GameEngine(
val trimmed = rawInput.trim.toLowerCase
trimmed match
case "quit" | "q" =>
// Client should handle quit logic; we just return
()
case "undo" =>
@@ -69,96 +58,55 @@ class GameEngine(
performRedo()
case "draw" =>
if currentHistory.halfMoveClock >= 100 then
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
if currentContext.halfMoveClock >= 100 then
invoker.clear()
notifyObservers(DrawClaimedEvent(currentBoard, currentHistory, currentTurn))
notifyObservers(DrawClaimedEvent(currentContext))
else
notifyObservers(InvalidMoveEvent(
currentBoard, currentHistory, currentTurn,
currentContext,
"Draw cannot be claimed: the 50-move rule has not been triggered."
))
case "" =>
val event = InvalidMoveEvent(
currentBoard,
currentHistory,
currentTurn,
"Please enter a valid move or command."
)
notifyObservers(event)
notifyObservers(InvalidMoveEvent(currentContext, "Please enter a valid move or command."))
case moveInput =>
Parser.parseMove(moveInput) match
case None =>
notifyObservers(InvalidMoveEvent(
currentBoard, currentHistory, currentTurn,
currentContext,
s"Invalid move format '$moveInput'. Use coordinate notation, e.g. e2e4."
))
case Some((from, to)) =>
handleParsedMove(from, to, moveInput)
handleParsedMove(from, to)
}
private def handleParsedMove(from: Square, to: Square, moveInput: String): Unit =
val cmd = MoveCommand(
from = from,
to = to,
previousBoard = Some(currentBoard),
previousHistory = Some(currentHistory),
previousTurn = Some(currentTurn)
)
GameController.processMove(currentBoard, currentHistory, currentTurn, moveInput) match
case MoveResult.InvalidFormat(_) | MoveResult.NoPiece | MoveResult.WrongColor | MoveResult.IllegalMove | MoveResult.Quit =>
handleFailedMove(moveInput)
private def handleParsedMove(from: Square, to: Square): Unit =
currentContext.board.pieceAt(from) match
case None =>
notifyObservers(InvalidMoveEvent(currentContext, "No piece on that square."))
case Some(piece) if piece.color != currentContext.turn =>
notifyObservers(InvalidMoveEvent(currentContext, "That is not your piece."))
case Some(piece) =>
val legal = ruleSet.legalMoves(currentContext, from)
// Find all legal moves going to `to`
val candidates = legal.filter(_.to == to)
candidates match
case Nil =>
notifyObservers(InvalidMoveEvent(currentContext, "Illegal move."))
case moves if isPromotionMove(piece, to) =>
// Multiple moves (one per promotion piece) — ask user to choose
val contextBefore = currentContext
pendingPromotion = Some(PendingPromotion(from, to, contextBefore))
notifyObservers(PromotionRequiredEvent(currentContext, from, to))
case move :: _ =>
executeMove(move)
case MoveResult.Moved(newBoard, newHistory, captured, newTurn) =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(newBoard, newHistory, newTurn, captured)))
invoker.execute(updatedCmd)
updateGameState(newBoard, newHistory, newTurn)
emitMoveEvent(from.toString, to.toString, captured, newTurn)
if currentHistory.halfMoveClock >= 100 then
notifyObservers(FiftyMoveRuleAvailableEvent(currentBoard, currentHistory, currentTurn))
case MoveResult.MovedInCheck(newBoard, newHistory, captured, newTurn) =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(newBoard, newHistory, newTurn, captured)))
invoker.execute(updatedCmd)
updateGameState(newBoard, newHistory, newTurn)
emitMoveEvent(from.toString, to.toString, captured, newTurn)
notifyObservers(CheckDetectedEvent(currentBoard, currentHistory, currentTurn))
if currentHistory.halfMoveClock >= 100 then
notifyObservers(FiftyMoveRuleAvailableEvent(currentBoard, currentHistory, currentTurn))
case MoveResult.Checkmate(winner) =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)))
invoker.execute(updatedCmd)
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
notifyObservers(CheckmateEvent(currentBoard, currentHistory, currentTurn, winner))
case MoveResult.Stalemate =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)))
invoker.execute(updatedCmd)
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
notifyObservers(StalemateEvent(currentBoard, currentHistory, currentTurn))
case MoveResult.PromotionRequired(promFrom, promTo, boardBefore, histBefore, _, promotingTurn) =>
pendingPromotion = Some(PendingPromotion(promFrom, promTo, boardBefore, histBefore, promotingTurn))
notifyObservers(PromotionRequiredEvent(currentBoard, currentHistory, currentTurn, promFrom, promTo))
/** Undo the last move. */
def undo(): Unit = synchronized {
performUndo()
}
/** Redo the last undone move. */
def redo(): Unit = synchronized {
performRedo()
}
private def isPromotionMove(piece: Piece, to: Square): Boolean =
piece.pieceType == PieceType.Pawn && {
val promoRank = if piece.color == Color.White then 7 else 0
to.rank.ordinal == promoRank
}
/** Apply a player's promotion piece choice.
* Must only be called when isPendingPromotion is true.
@@ -166,187 +114,205 @@ class GameEngine(
def completePromotion(piece: PromotionPiece): Unit = synchronized {
pendingPromotion match
case None =>
notifyObservers(InvalidMoveEvent(currentBoard, currentHistory, currentTurn, "No promotion pending."))
notifyObservers(InvalidMoveEvent(currentContext, "No promotion pending."))
case Some(pending) =>
pendingPromotion = None
val cmd = MoveCommand(
from = pending.from,
to = pending.to,
previousBoard = Some(pending.boardBefore),
previousHistory = Some(pending.historyBefore),
previousTurn = Some(pending.turn)
)
completePromotionFn(
pending.boardBefore, pending.historyBefore,
pending.from, pending.to, piece, pending.turn
) match
case MoveResult.Moved(newBoard, newHistory, captured, newTurn) =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(newBoard, newHistory, newTurn, captured)))
invoker.execute(updatedCmd)
updateGameState(newBoard, newHistory, newTurn)
emitMoveEvent(pending.from.toString, pending.to.toString, captured, newTurn)
case MoveResult.MovedInCheck(newBoard, newHistory, captured, newTurn) =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(newBoard, newHistory, newTurn, captured)))
invoker.execute(updatedCmd)
updateGameState(newBoard, newHistory, newTurn)
emitMoveEvent(pending.from.toString, pending.to.toString, captured, newTurn)
notifyObservers(CheckDetectedEvent(currentBoard, currentHistory, currentTurn))
case MoveResult.Checkmate(winner) =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)))
invoker.execute(updatedCmd)
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
notifyObservers(CheckmateEvent(currentBoard, currentHistory, currentTurn, winner))
case MoveResult.Stalemate =>
val updatedCmd = cmd.copy(moveResult = Some(de.nowchess.chess.command.MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)))
invoker.execute(updatedCmd)
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
notifyObservers(StalemateEvent(currentBoard, currentHistory, currentTurn))
case _ =>
notifyObservers(InvalidMoveEvent(currentBoard, currentHistory, currentTurn, "Error completing promotion."))
val move = Move(pending.from, pending.to, MoveType.Promotion(piece))
// Verify it's actually legal
val legal = ruleSet.legalMoves(currentContext, pending.from)
if legal.contains(move) then
executeMove(move)
else
notifyObservers(InvalidMoveEvent(currentContext, "Error completing promotion."))
}
/** Validate and load a PGN string.
* Each move is replayed through the command system so undo/redo is available after loading.
* Returns Right(()) on success; Left(error) if any move is illegal or the position impossible. */
def loadPgn(pgn: String): Either[String, Unit] = synchronized {
PgnParser.validatePgn(pgn) match
case Left(err) =>
Left(err)
case Right(game) =>
val initialBoardBeforeLoad = currentBoard
val initialHistoryBeforeLoad = currentHistory
val initialTurnBeforeLoad = currentTurn
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
pendingPromotion = None
invoker.clear()
/** Undo the last move. */
def undo(): Unit = synchronized { performUndo() }
var error: Option[String] = None
import scala.util.control.Breaks._
breakable {
game.moves.foreach { move =>
handleParsedMove(move.from, move.to, s"${move.from}${move.to}")
move.promotionPiece.foreach(completePromotion)
// If the move failed to execute properly, stop and report
// (validatePgn should have caught this, but we're being safe)
if pendingPromotion.isDefined && move.promotionPiece.isEmpty then
error = Some(s"Promotion required for move ${move.from}${move.to}")
break()
}
/** Redo the last undone move. */
def redo(): Unit = synchronized { performRedo() }
/** Load a game using the provided importer.
* If the imported context has moves, they are replayed through the command system.
* Otherwise, the position is set directly.
* Notifies observers with PgnLoadedEvent on success.
*/
def loadGame(importer: GameContextImport, input: String): Either[String, Unit] = synchronized {
importer.importGameContext(input) match
case Left(err) => Left(err)
case Right(ctx) =>
replayGame(ctx).map { _ =>
notifyObservers(PgnLoadedEvent(currentContext))
}
error match
case Some(err) =>
currentBoard = initialBoardBeforeLoad
currentHistory = initialHistoryBeforeLoad
currentTurn = initialTurnBeforeLoad
Left(err)
case None =>
notifyObservers(PgnLoadedEvent(currentBoard, currentHistory, currentTurn))
Right(())
}
private def replayGame(ctx: GameContext): Either[String, Unit] =
val savedContext = currentContext
currentContext = GameContext.initial
pendingPromotion = None
invoker.clear()
if ctx.moves.isEmpty then
currentContext = ctx
Right(())
else
replayMoves(ctx.moves, savedContext)
private[engine] def replayMoves(moves: List[Move], savedContext: GameContext): Either[String, Unit] =
var error: Option[String] = None
moves.foreach: move =>
if error.isEmpty then
handleParsedMove(move.from, move.to)
move.moveType match {
case MoveType.Promotion(pp) =>
if pendingPromotion.isDefined then
completePromotion(pp)
else
error = Some(s"Promotion required for move ${move.from}${move.to}")
case _ => ()
}
error match
case Some(err) =>
currentContext = savedContext
Left(err)
case None =>
Right(())
/** Export the current game context using the provided exporter. */
def exportGame(exporter: GameContextExport): String = synchronized {
exporter.exportGameContext(currentContext)
}
/** Load an arbitrary board position, clearing all history and undo/redo state. */
def loadPosition(board: Board, history: GameHistory, turn: Color): Unit = synchronized {
currentBoard = board
currentHistory = history
currentTurn = turn
def loadPosition(newContext: GameContext): Unit = synchronized {
currentContext = newContext
pendingPromotion = None
invoker.clear()
notifyObservers(BoardResetEvent(currentBoard, currentHistory, currentTurn))
notifyObservers(BoardResetEvent(currentContext))
}
/** Reset the board to initial position. */
def reset(): Unit = synchronized {
currentBoard = Board.initial
currentHistory = GameHistory.empty
currentTurn = Color.White
currentContext = GameContext.initial
invoker.clear()
notifyObservers(BoardResetEvent(
currentBoard,
currentHistory,
currentTurn
))
notifyObservers(BoardResetEvent(currentContext))
}
// ──── Private Helpers ────
// ──── Private helpers ────
private def executeMove(move: Move): Unit =
val contextBefore = currentContext
val nextContext = ruleSet.applyMove(currentContext, move)
val captured = computeCaptured(currentContext, move)
val cmd = MoveCommand(
from = move.from,
to = move.to,
moveResult = Some(MoveResult.Successful(nextContext, captured)),
previousContext = Some(contextBefore),
notation = translateMoveToNotation(move, contextBefore.board)
)
invoker.execute(cmd)
currentContext = nextContext
notifyObservers(MoveExecutedEvent(
currentContext,
move.from.toString,
move.to.toString,
captured.map(c => s"${c.color.label} ${c.pieceType.label}")
))
if ruleSet.isCheckmate(currentContext) then
val winner = currentContext.turn.opposite
notifyObservers(CheckmateEvent(currentContext, winner))
invoker.clear()
currentContext = GameContext.initial
else if ruleSet.isStalemate(currentContext) then
notifyObservers(StalemateEvent(currentContext))
invoker.clear()
currentContext = GameContext.initial
else if ruleSet.isCheck(currentContext) then
notifyObservers(CheckDetectedEvent(currentContext))
if currentContext.halfMoveClock >= 100 then
notifyObservers(FiftyMoveRuleAvailableEvent(currentContext))
private def translateMoveToNotation(move: Move, boardBefore: Board): String =
move.moveType match
case MoveType.CastleKingside => "O-O"
case MoveType.CastleQueenside => "O-O-O"
case MoveType.EnPassant => enPassantNotation(move)
case MoveType.Promotion(pp) => promotionNotation(move, pp)
case MoveType.Normal(isCapture) => normalMoveNotation(move, boardBefore, isCapture)
private def enPassantNotation(move: Move): String =
s"${move.from.file.toString.toLowerCase}x${move.to}"
private def promotionNotation(move: Move, piece: PromotionPiece): String =
val ppChar = piece match
case PromotionPiece.Queen => "Q"
case PromotionPiece.Rook => "R"
case PromotionPiece.Bishop => "B"
case PromotionPiece.Knight => "N"
s"${move.to}=$ppChar"
private[engine] def normalMoveNotation(move: Move, boardBefore: Board, isCapture: Boolean): String =
boardBefore.pieceAt(move.from).map(_.pieceType) match
case Some(PieceType.Pawn) =>
if isCapture then s"${move.from.file.toString.toLowerCase}x${move.to}"
else move.to.toString
case Some(pt) =>
val letter = pieceNotation(pt)
if isCapture then s"${letter}x${move.to}" else s"$letter${move.to}"
case None => move.to.toString
private[engine] def pieceNotation(pieceType: PieceType): String =
pieceType match
case PieceType.Knight => "N"
case PieceType.Bishop => "B"
case PieceType.Rook => "R"
case PieceType.Queen => "Q"
case PieceType.King => "K"
case _ => ""
private def computeCaptured(context: GameContext, move: Move): Option[Piece] =
move.moveType match
case MoveType.EnPassant =>
// Captured pawn is on the same rank as the moving pawn, same file as destination
val capturedSquare = Square(move.to.file, move.from.rank)
context.board.pieceAt(capturedSquare)
case MoveType.CastleKingside | MoveType.CastleQueenside =>
None
case _ =>
context.board.pieceAt(move.to)
private def performUndo(): Unit =
if invoker.canUndo then
val cmd = invoker.history(invoker.getCurrentIndex)
(cmd: @unchecked) match
case moveCmd: MoveCommand =>
val notation = currentHistory.moves.lastOption.map(PgnExporter.moveToAlgebraic).getOrElse("")
moveCmd.previousBoard.foreach(currentBoard = _)
moveCmd.previousHistory.foreach(currentHistory = _)
moveCmd.previousTurn.foreach(currentTurn = _)
moveCmd.previousContext.foreach(currentContext = _)
invoker.undo()
notifyObservers(MoveUndoneEvent(currentBoard, currentHistory, currentTurn, notation))
notifyObservers(MoveUndoneEvent(currentContext, moveCmd.notation))
else
notifyObservers(InvalidMoveEvent(currentBoard, currentHistory, currentTurn, "Nothing to undo."))
notifyObservers(InvalidMoveEvent(currentContext, "Nothing to undo."))
private def performRedo(): Unit =
if invoker.canRedo then
val cmd = invoker.history(invoker.getCurrentIndex + 1)
(cmd: @unchecked) match
case moveCmd: MoveCommand =>
for case de.nowchess.chess.command.MoveResult.Successful(nb, nh, nt, cap) <- moveCmd.moveResult do
updateGameState(nb, nh, nt)
for case MoveResult.Successful(nextCtx, cap) <- moveCmd.moveResult do
currentContext = nextCtx
invoker.redo()
val notation = nh.moves.lastOption.map(PgnExporter.moveToAlgebraic).getOrElse("")
val capturedDesc = cap.map(c => s"${c.color.label} ${c.pieceType.label}")
notifyObservers(MoveRedoneEvent(currentBoard, currentHistory, currentTurn, notation, moveCmd.from.toString, moveCmd.to.toString, capturedDesc))
notifyObservers(MoveRedoneEvent(
currentContext,
moveCmd.notation,
moveCmd.from.toString,
moveCmd.to.toString,
capturedDesc
))
else
notifyObservers(InvalidMoveEvent(currentBoard, currentHistory, currentTurn, "Nothing to redo."))
private def updateGameState(newBoard: Board, newHistory: GameHistory, newTurn: Color): Unit =
currentBoard = newBoard
currentHistory = newHistory
currentTurn = newTurn
private def emitMoveEvent(fromSq: String, toSq: String, captured: Option[Piece], newTurn: Color): Unit =
val capturedDesc = captured.map(c => s"${c.color.label} ${c.pieceType.label}")
notifyObservers(MoveExecutedEvent(
currentBoard,
currentHistory,
newTurn,
fromSq,
toSq,
capturedDesc
))
private def handleFailedMove(moveInput: String): Unit =
(GameController.processMove(currentBoard, currentHistory, currentTurn, moveInput): @unchecked) match
case MoveResult.NoPiece =>
notifyObservers(InvalidMoveEvent(
currentBoard,
currentHistory,
currentTurn,
"No piece on that square."
))
case MoveResult.WrongColor =>
notifyObservers(InvalidMoveEvent(
currentBoard,
currentHistory,
currentTurn,
"That is not your piece."
))
case MoveResult.IllegalMove =>
notifyObservers(InvalidMoveEvent(
currentBoard,
currentHistory,
currentTurn,
"Illegal move."
))
notifyObservers(InvalidMoveEvent(currentContext, "Nothing to redo."))
@@ -1,23 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
enum CastleSide:
case Kingside, Queenside
extension (b: Board)
def withCastle(color: Color, side: CastleSide): Board =
val rank = if color == Color.White then Rank.R1 else Rank.R8
val kingFrom = Square(File.E, rank)
val (kingTo, rookFrom, rookTo) = side match
case CastleSide.Kingside =>
(Square(File.G, rank), Square(File.H, rank), Square(File.F, rank))
case CastleSide.Queenside =>
(Square(File.C, rank), Square(File.A, rank), Square(File.D, rank))
val king = b.pieceAt(kingFrom).get
val rook = b.pieceAt(rookFrom).get
b.removed(kingFrom).removed(rookFrom)
.updated(kingTo, king)
.updated(rookTo, rook)
@@ -1,31 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.{Color, File, Rank, Square}
import de.nowchess.api.game.CastlingRights
/** Derives castling rights from move history. */
object CastlingRightsCalculator:
def deriveCastlingRights(history: GameHistory, color: Color): CastlingRights =
val (kingRow, kingsideRookFile, queensideRookFile) = color match
case Color.White => (Rank.R1, File.H, File.A)
case Color.Black => (Rank.R8, File.H, File.A)
// Check if king has moved
val kingHasMoved = history.moves.exists: move =>
move.from == Square(File.E, kingRow) || move.castleSide.isDefined
if kingHasMoved then
CastlingRights.None
else
// Check if kingside rook has moved or was captured
val kingsideLost = history.moves.exists: move =>
move.from == Square(kingsideRookFile, kingRow) ||
move.to == Square(kingsideRookFile, kingRow)
// Check if queenside rook has moved or was captured
val queensideLost = history.moves.exists: move =>
move.from == Square(queensideRookFile, kingRow) ||
move.to == Square(queensideRookFile, kingRow)
CastlingRights(kingSide = !kingsideLost, queenSide = !queensideLost)
@@ -1,32 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
object EnPassantCalculator:
/** Returns the en passant target square if the last move was a double pawn push.
* The target is the square the pawn passed through (e.g. e2e4 yields e3).
*/
def enPassantTarget(board: Board, history: GameHistory): Option[Square] =
history.moves.lastOption.flatMap: move =>
val rankDiff = move.to.rank.ordinal - move.from.rank.ordinal
val isDoublePush = math.abs(rankDiff) == 2
val isPawn = board.pieceAt(move.to).exists(_.pieceType == PieceType.Pawn)
if isDoublePush && isPawn then
val midRankIdx = move.from.rank.ordinal + rankDiff / 2
Some(Square(move.to.file, Rank.values(midRankIdx)))
else None
/** True if moving from→to is an en passant capture. */
def isEnPassant(board: Board, history: GameHistory, from: Square, to: Square): Boolean =
board.pieceAt(from).exists(_.pieceType == PieceType.Pawn) &&
enPassantTarget(board, history).contains(to) &&
math.abs(to.file.ordinal - from.file.ordinal) == 1
/** Returns the square of the pawn to remove when an en passant capture lands on `to`.
* White captures upward → captured pawn is one rank below `to`.
* Black captures downward → captured pawn is one rank above `to`.
*/
def capturedPawnSquare(to: Square, color: Color): Square =
val capturedRankIdx = to.rank.ordinal + (if color == Color.White then -1 else 1)
Square(to.file, Rank.values(capturedRankIdx))
@@ -1,49 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.{PieceType, Square}
import de.nowchess.api.move.PromotionPiece
/** A single move recorded in the game history. Distinct from api.move.Move which represents user intent. */
case class HistoryMove(
from: Square,
to: Square,
castleSide: Option[CastleSide],
promotionPiece: Option[PromotionPiece] = None,
pieceType: PieceType = PieceType.Pawn,
isCapture: Boolean = false
)
/** Complete game history: ordered list of moves plus the half-move clock for the 50-move rule.
*
* @param moves moves played so far, oldest first
* @param halfMoveClock plies since the last pawn move or capture (FIDE 50-move rule counter)
*/
case class GameHistory(moves: List[HistoryMove] = List.empty, halfMoveClock: Int = 0):
/** Add a raw HistoryMove record. Clock increments by 1.
* Use the coordinate overload when you know whether the move is a pawn move or capture.
*/
def addMove(move: HistoryMove): GameHistory =
GameHistory(moves :+ move, halfMoveClock + 1)
/** Add a move by coordinates.
*
* @param wasPawnMove true when the moving piece is a pawn — resets the clock to 0
* @param wasCapture true when a piece was captured (including en passant) — resets the clock to 0
*
* If neither flag is set the clock increments by 1.
*/
def addMove(
from: Square,
to: Square,
castleSide: Option[CastleSide] = None,
promotionPiece: Option[PromotionPiece] = None,
wasPawnMove: Boolean = false,
wasCapture: Boolean = false,
pieceType: PieceType = PieceType.Pawn
): GameHistory =
val newClock = if wasPawnMove || wasCapture then 0 else halfMoveClock + 1
GameHistory(moves :+ HistoryMove(from, to, castleSide, promotionPiece, pieceType, wasCapture), newClock)
object GameHistory:
val empty: GameHistory = GameHistory()
@@ -1,47 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
import de.nowchess.chess.logic.GameHistory
enum PositionStatus:
case Normal, InCheck, Mated, Drawn
object GameRules:
/** True if `color`'s king is under attack on this board. */
def isInCheck(board: Board, color: Color): Boolean =
board.pieces
.collectFirst { case (sq, p) if p.color == color && p.pieceType == PieceType.King => sq }
.exists { kingSq =>
board.pieces.exists { case (sq, piece) =>
piece.color != color &&
MoveValidator.legalTargets(board, sq).contains(kingSq)
}
}
/** All (from, to) moves for `color` that do not leave their own king in check. */
def legalMoves(board: Board, history: GameHistory, color: Color): Set[(Square, Square)] =
board.pieces
.collect { case (from, piece) if piece.color == color => from }
.flatMap { from =>
MoveValidator.legalTargets(board, history, from) // context-aware: includes castling
.filter { to =>
val newBoard =
if MoveValidator.isCastle(board, from, to) then
board.withCastle(color, MoveValidator.castleSide(from, to))
else
board.withMove(from, to)._1
!isInCheck(newBoard, color)
}
.map(to => from -> to)
}
.toSet
/** Position status for the side whose turn it is (`color`). */
def gameStatus(board: Board, history: GameHistory, color: Color): PositionStatus =
val moves = legalMoves(board, history, color)
val inCheck = isInCheck(board, color)
if moves.isEmpty && inCheck then PositionStatus.Mated
else if moves.isEmpty then PositionStatus.Drawn
else if inCheck then PositionStatus.InCheck
else PositionStatus.Normal
@@ -1,183 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
import de.nowchess.chess.logic.{CastleSide, GameHistory}
object MoveValidator:
/** Returns true if the move is geometrically legal for the piece on `from`,
* ignoring check/pin but respecting:
* - correct movement pattern for the piece type
* - cannot capture own pieces
* - sliding pieces (bishop, rook, queen) are blocked by intervening pieces
*/
def isLegal(board: Board, from: Square, to: Square): Boolean =
legalTargets(board, from).contains(to)
/** All squares a piece on `from` can legally move to (same rules as isLegal). */
def legalTargets(board: Board, from: Square): Set[Square] =
board.pieceAt(from) match
case None => Set.empty
case Some(piece) =>
piece.pieceType match
case PieceType.Pawn => pawnTargets(board, from, piece.color)
case PieceType.Knight => knightTargets(board, from, piece.color)
case PieceType.Bishop => slide(board, from, piece.color, diagonalDeltas)
case PieceType.Rook => slide(board, from, piece.color, orthogonalDeltas)
case PieceType.Queen => slide(board, from, piece.color, diagonalDeltas ++ orthogonalDeltas)
case PieceType.King => kingTargets(board, from, piece.color)
// ── helpers ────────────────────────────────────────────────────────────────
private val diagonalDeltas: List[(Int, Int)] = List((1, 1), (1, -1), (-1, 1), (-1, -1))
private val orthogonalDeltas: List[(Int, Int)] = List((1, 0), (-1, 0), (0, 1), (0, -1))
private val knightDeltas: List[(Int, Int)] =
List((1, 2), (1, -2), (-1, 2), (-1, -2), (2, 1), (2, -1), (-2, 1), (-2, -1))
/** Try to construct a Square from integer file/rank indices (0-based). */
private def squareAt(fileIdx: Int, rankIdx: Int): Option[Square] =
Option.when(fileIdx >= 0 && fileIdx <= 7 && rankIdx >= 0 && rankIdx <= 7)(
Square(File.values(fileIdx), Rank.values(rankIdx))
)
/** True when `sq` is occupied by a piece of `color`. */
private def isOwnPiece(board: Board, sq: Square, color: Color): Boolean =
board.pieceAt(sq).exists(_.color == color)
/** True when `sq` is occupied by a piece of the opposite color. */
private def isEnemyPiece(board: Board, sq: Square, color: Color): Boolean =
board.pieceAt(sq).exists(_.color != color)
/** Sliding move generation along a list of direction deltas.
* Each direction continues until the board edge, an own piece, or the first
* enemy piece (which is included as a capture target).
*/
private def slide(board: Board, from: Square, color: Color, deltas: List[(Int, Int)]): Set[Square] =
val fi = from.file.ordinal
val ri = from.rank.ordinal
deltas.flatMap: (df, dr) =>
Iterator
.iterate((fi + df, ri + dr)) { case (f, r) => (f + df, r + dr) }
.takeWhile { case (f, r) => f >= 0 && f <= 7 && r >= 0 && r <= 7 }
.map { case (f, r) => Square(File.values(f), Rank.values(r)) }
.foldLeft((List.empty[Square], false)):
case ((acc, stopped), sq) =>
if stopped then (acc, true)
else if isOwnPiece(board, sq, color) then (acc, true) // blocked — stop, no capture
else if isEnemyPiece(board, sq, color) then (acc :+ sq, true) // capture — stop after
else (acc :+ sq, false) // empty — continue
._1
.toSet
private def pawnTargets(board: Board, from: Square, color: Color): Set[Square] =
val fi = from.file.ordinal
val ri = from.rank.ordinal
val dir = if color == Color.White then 1 else -1
val startRank = if color == Color.White then Rank.R2.ordinal else Rank.R7.ordinal
val oneStep = squareAt(fi, ri + dir)
// Forward one square (only if empty)
val forward1: Set[Square] = oneStep match
case Some(sq) if board.pieceAt(sq).isEmpty => Set(sq)
case _ => Set.empty
// Forward two squares from starting rank (only if both intermediate squares are empty)
val forward2: Set[Square] =
if ri == startRank && forward1.nonEmpty then
squareAt(fi, ri + 2 * dir) match
case Some(sq) if board.pieceAt(sq).isEmpty => Set(sq)
case _ => Set.empty
else Set.empty
// Diagonal captures (only if enemy piece present)
val captures: Set[Square] =
List(-1, 1).flatMap: df =>
squareAt(fi + df, ri + dir).filter(sq => isEnemyPiece(board, sq, color))
.toSet
forward1 ++ forward2 ++ captures
private def knightTargets(board: Board, from: Square, color: Color): Set[Square] =
val fi = from.file.ordinal
val ri = from.rank.ordinal
knightDeltas.flatMap: (df, dr) =>
squareAt(fi + df, ri + dr).filterNot(sq => isOwnPiece(board, sq, color))
.toSet
private def kingTargets(board: Board, from: Square, color: Color): Set[Square] =
val fi = from.file.ordinal
val ri = from.rank.ordinal
(diagonalDeltas ++ orthogonalDeltas).flatMap: (df, dr) =>
squareAt(fi + df, ri + dr).filterNot(sq => isOwnPiece(board, sq, color))
.toSet
// ── Castling helpers ────────────────────────────────────────────────────────
private def isAttackedBy(board: Board, sq: Square, attackerColor: Color): Boolean =
board.pieces.exists { case (from, piece) =>
piece.color == attackerColor && legalTargets(board, from).contains(sq)
}
def isCastle(board: Board, from: Square, to: Square): Boolean =
board.pieceAt(from).exists(_.pieceType == PieceType.King) &&
math.abs(to.file.ordinal - from.file.ordinal) == 2
def castleSide(from: Square, to: Square): CastleSide =
if to.file.ordinal > from.file.ordinal then CastleSide.Kingside else CastleSide.Queenside
def castlingTargets(board: Board, history: GameHistory, color: Color): Set[Square] =
val rights = CastlingRightsCalculator.deriveCastlingRights(history, color)
val rank = if color == Color.White then Rank.R1 else Rank.R8
val kingSq = Square(File.E, rank)
val enemy = color.opposite
if !board.pieceAt(kingSq).contains(Piece(color, PieceType.King)) ||
GameRules.isInCheck(board, color) then Set.empty
else
val kingsideSq = Option.when(
rights.kingSide &&
board.pieceAt(Square(File.H, rank)).contains(Piece(color, PieceType.Rook)) &&
List(Square(File.F, rank), Square(File.G, rank)).forall(s => board.pieceAt(s).isEmpty) &&
!List(Square(File.F, rank), Square(File.G, rank)).exists(s => isAttackedBy(board, s, enemy))
)(Square(File.G, rank))
val queensideSq = Option.when(
rights.queenSide &&
board.pieceAt(Square(File.A, rank)).contains(Piece(color, PieceType.Rook)) &&
List(Square(File.B, rank), Square(File.C, rank), Square(File.D, rank)).forall(s => board.pieceAt(s).isEmpty) &&
!List(Square(File.D, rank), Square(File.C, rank)).exists(s => isAttackedBy(board, s, enemy))
)(Square(File.C, rank))
kingsideSq.toSet ++ queensideSq.toSet
def legalTargets(board: Board, history: GameHistory, from: Square): Set[Square] =
board.pieceAt(from) match
case Some(piece) if piece.pieceType == PieceType.King =>
legalTargets(board, from) ++ castlingTargets(board, history, piece.color)
case Some(piece) if piece.pieceType == PieceType.Pawn =>
pawnTargets(board, history, from, piece.color)
case _ =>
legalTargets(board, from)
private def pawnTargets(board: Board, history: GameHistory, from: Square, color: Color): Set[Square] =
val existing = pawnTargets(board, from, color)
val fi = from.file.ordinal
val ri = from.rank.ordinal
val dir = if color == Color.White then 1 else -1
val epCapture: Set[Square] =
EnPassantCalculator.enPassantTarget(board, history).filter: target =>
squareAt(fi - 1, ri + dir).contains(target) || squareAt(fi + 1, ri + dir).contains(target)
.toSet
existing ++ epCapture
def isLegal(board: Board, history: GameHistory, from: Square, to: Square): Boolean =
legalTargets(board, history, from).contains(to)
/** Returns true if the piece on `from` is a pawn moving to its back rank (promotion). */
def isPromotionMove(board: Board, from: Square, to: Square): Boolean =
board.pieceAt(from) match
case Some(Piece(_, PieceType.Pawn)) =>
(from.rank == Rank.R7 && to.rank == Rank.R8) ||
(from.rank == Rank.R2 && to.rank == Rank.R1)
case _ => false
@@ -1,60 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.game.{CastlingRights, GameState}
import de.nowchess.api.board.Color
object FenExporter:
/** Convert a Board to FEN piece-placement string (rank 8 to rank 1, separated by '/'). */
def boardToFen(board: Board): String =
Rank.values.reverse
.map(rank => buildRankString(board, rank))
.mkString("/")
/** Build the FEN representation for a single rank. */
private def buildRankString(board: Board, rank: Rank): String =
val rankSquares = File.values.map(file => Square(file, rank))
val rankChars = scala.collection.mutable.ListBuffer[Char]()
var emptyCount = 0
for square <- rankSquares do
board.pieceAt(square) match
case Some(piece) =>
if emptyCount > 0 then
rankChars += emptyCount.toString.charAt(0)
emptyCount = 0
rankChars += pieceToPgnChar(piece)
case None =>
emptyCount += 1
if emptyCount > 0 then rankChars += emptyCount.toString.charAt(0)
rankChars.mkString
/** Convert a GameState to a complete FEN string. */
def gameStateToFen(state: GameState): String =
val piecePlacement = state.piecePlacement
val activeColor = if state.activeColor == Color.White then "w" else "b"
val castling = castlingString(state.castlingWhite, state.castlingBlack)
val enPassant = state.enPassantTarget.map(_.toString).getOrElse("-")
s"$piecePlacement $activeColor $castling $enPassant ${state.halfMoveClock} ${state.fullMoveNumber}"
/** Convert castling rights to FEN notation. */
private def castlingString(white: CastlingRights, black: CastlingRights): String =
val wk = if white.kingSide then "K" else ""
val wq = if white.queenSide then "Q" else ""
val bk = if black.kingSide then "k" else ""
val bq = if black.queenSide then "q" else ""
val result = s"$wk$wq$bk$bq"
if result.isEmpty then "-" else result
/** Convert a Piece to its FEN character (uppercase = White, lowercase = Black). */
private def pieceToPgnChar(piece: Piece): Char =
val base = piece.pieceType match
case PieceType.Pawn => 'p'
case PieceType.Knight => 'n'
case PieceType.Bishop => 'b'
case PieceType.Rook => 'r'
case PieceType.Queen => 'q'
case PieceType.King => 'k'
if piece.color == Color.White then base.toUpper else base
@@ -1,103 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.game.{CastlingRights, GameState, GameStatus}
object FenParser:
/** Parse a complete FEN string into a GameState.
* Returns None if the format is invalid. */
def parseFen(fen: String): Option[GameState] =
val parts = fen.trim.split("\\s+")
Option.when(parts.length == 6)(parts).flatMap: parts =>
for
_ <- parseBoard(parts(0))
activeColor <- parseColor(parts(1))
castlingRights <- parseCastling(parts(2))
enPassant <- parseEnPassant(parts(3))
halfMoveClock <- parts(4).toIntOption
fullMoveNumber <- parts(5).toIntOption
if halfMoveClock >= 0 && fullMoveNumber >= 1
yield GameState(
piecePlacement = parts(0),
activeColor = activeColor,
castlingWhite = castlingRights._1,
castlingBlack = castlingRights._2,
enPassantTarget = enPassant,
halfMoveClock = halfMoveClock,
fullMoveNumber = fullMoveNumber,
status = GameStatus.InProgress
)
/** Parse active color ("w" or "b"). */
private def parseColor(s: String): Option[Color] =
if s == "w" then Some(Color.White)
else if s == "b" then Some(Color.Black)
else None
/** Parse castling rights string (e.g. "KQkq", "K", "-") into rights for White and Black. */
private def parseCastling(s: String): Option[(CastlingRights, CastlingRights)] =
if s == "-" then
Some((CastlingRights.None, CastlingRights.None))
else if s.length <= 4 && s.forall(c => "KQkq".contains(c)) then
val white = CastlingRights(kingSide = s.contains('K'), queenSide = s.contains('Q'))
val black = CastlingRights(kingSide = s.contains('k'), queenSide = s.contains('q'))
Some((white, black))
else
None
/** Parse en passant target square ("-" for none, or algebraic like "e3"). */
private def parseEnPassant(s: String): Option[Option[Square]] =
if s == "-" then Some(None)
else Square.fromAlgebraic(s).map(Some(_))
/** Parses a FEN piece-placement string (rank 8 to rank 1, separated by '/') into a Board.
* Returns None if the format is invalid. */
def parseBoard(fen: String): Option[Board] =
val rankStrings = fen.split("/", -1)
if rankStrings.length != 8 then None
else
// Parse each rank, collecting all (Square, Piece) pairs or failing on the first error
val parsedRanks: Option[List[List[(Square, Piece)]]] =
rankStrings.zipWithIndex.foldLeft(Option(List.empty[List[(Square, Piece)]])):
case (None, _) => None
case (Some(acc), (rankStr, rankIdx)) =>
val rank = Rank.values(7 - rankIdx) // ranks go 8→1, so reverse
parsePieceRank(rankStr, rank).map(squares => acc :+ squares)
parsedRanks.map(ranks => Board(ranks.flatten.toMap))
/** Parse a single rank string (e.g. "rnbqkbnr" or "p3p3") into a list of (Square, Piece) pairs.
* Returns None if the rank string contains invalid characters or the wrong number of files. */
private def parsePieceRank(rankStr: String, rank: Rank): Option[List[(Square, Piece)]] =
var fileIdx = 0
val squares = scala.collection.mutable.ListBuffer[(Square, Piece)]()
var failed = false
for c <- rankStr if !failed do
if fileIdx > 7 then
failed = true
else if c.isDigit then
fileIdx += c.asDigit
else
charToPiece(c) match
case None => failed = true
case Some(piece) =>
val file = File.values(fileIdx)
squares += (Square(file, rank) -> piece)
fileIdx += 1
if failed || fileIdx != 8 then None
else Some(squares.toList)
/** Convert a FEN piece character to a Piece. Uppercase = White, lowercase = Black. */
private def charToPiece(c: Char): Option[Piece] =
val color = if Character.isUpperCase(c) then Color.White else Color.Black
val pieceTypeOpt = c.toLower match
case 'p' => Some(PieceType.Pawn)
case 'n' => Some(PieceType.Knight)
case 'b' => Some(PieceType.Bishop)
case 'r' => Some(PieceType.Rook)
case 'q' => Some(PieceType.Queen)
case 'k' => Some(PieceType.King)
case _ => None
pieceTypeOpt.map(pt => Piece(color, pt))
@@ -1,54 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.{PieceType, *}
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{CastleSide, GameHistory, HistoryMove}
object PgnExporter:
/** Export a game with headers and history to PGN format. */
def exportGame(headers: Map[String, String], history: GameHistory): String =
val headerLines = headers.map { case (key, value) =>
s"""[$key "$value"]"""
}.mkString("\n")
val moveText = if history.moves.isEmpty then ""
else
val groupedMoves = history.moves.zipWithIndex.groupBy(_._2 / 2)
val moveLines = for (moveNumber, movePairs) <- groupedMoves.toList.sortBy(_._1) yield
val moveNum = moveNumber + 1
val whiteMoveStr = movePairs.find(_._2 % 2 == 0).map(p => moveToAlgebraic(p._1)).getOrElse("")
val blackMoveStr = movePairs.find(_._2 % 2 == 1).map(p => moveToAlgebraic(p._1)).getOrElse("")
if blackMoveStr.isEmpty then s"$moveNum. $whiteMoveStr"
else s"$moveNum. $whiteMoveStr $blackMoveStr"
val termination = headers.getOrElse("Result", "*")
moveLines.mkString(" ") + s" $termination"
if headerLines.isEmpty then moveText
else if moveText.isEmpty then headerLines
else s"$headerLines\n\n$moveText"
/** Convert a HistoryMove to Standard Algebraic Notation. */
def moveToAlgebraic(move: HistoryMove): String =
move.castleSide match
case Some(CastleSide.Kingside) => "O-O"
case Some(CastleSide.Queenside) => "O-O-O"
case None =>
val dest = move.to.toString
val capStr = if move.isCapture then "x" else ""
val promSuffix = move.promotionPiece match
case Some(PromotionPiece.Queen) => "=Q"
case Some(PromotionPiece.Rook) => "=R"
case Some(PromotionPiece.Bishop) => "=B"
case Some(PromotionPiece.Knight) => "=N"
case None => ""
move.pieceType match
case PieceType.Pawn =>
if move.isCapture then s"${move.from.file.toString.toLowerCase}x$dest$promSuffix"
else s"$dest$promSuffix"
case PieceType.Knight => s"N$capStr$dest$promSuffix"
case PieceType.Bishop => s"B$capStr$dest$promSuffix"
case PieceType.Rook => s"R$capStr$dest$promSuffix"
case PieceType.Queen => s"Q$capStr$dest$promSuffix"
case PieceType.King => s"K$capStr$dest$promSuffix"
@@ -1,267 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{CastleSide, GameHistory, HistoryMove, GameRules, MoveValidator, withCastle}
/** A parsed PGN game containing headers and the resolved move list. */
case class PgnGame(
headers: Map[String, String],
moves: List[HistoryMove]
)
object PgnParser:
/** Strictly validate a PGN text.
* Returns Right(PgnGame) if every move token is a legal move in the evolving position.
* Returns Left(error message) on the first illegal or impossible move, or any unrecognised token. */
def validatePgn(pgn: String): Either[String, PgnGame] =
val lines = pgn.split("\n").map(_.trim)
val (headerLines, rest) = lines.span(_.startsWith("["))
val headers = parseHeaders(headerLines)
val moveText = rest.mkString(" ")
validateMovesText(moveText).map(moves => PgnGame(headers, moves))
/** Parse a complete PGN text into a PgnGame with headers and moves.
* Always succeeds (returns Some); malformed tokens are silently skipped. */
def parsePgn(pgn: String): Option[PgnGame] =
val lines = pgn.split("\n").map(_.trim)
val (headerLines, rest) = lines.span(_.startsWith("["))
val headers = parseHeaders(headerLines)
val moveText = rest.mkString(" ")
val moves = parseMovesText(moveText)
Some(PgnGame(headers, moves))
/** Parse PGN header lines of the form [Key "Value"]. */
private def parseHeaders(lines: Array[String]): Map[String, String] =
val pattern = """^\[(\w+)\s+"([^"]*)"\s*\]$""".r
lines.flatMap(line => pattern.findFirstMatchIn(line).map(m => m.group(1) -> m.group(2))).toMap
/** Parse the move-text section (e.g. "1. e4 e5 2. Nf3") into resolved HistoryMoves. */
private def parseMovesText(moveText: String): List[HistoryMove] =
val tokens = moveText.split("\\s+").filter(_.nonEmpty)
// Fold over tokens, threading (board, history, currentColor, accumulator)
val (_, _, _, moves) = tokens.foldLeft(
(Board.initial, GameHistory.empty, Color.White, List.empty[HistoryMove])
):
case (state @ (board, history, color, acc), token) =>
// Skip move-number markers (e.g. "1.", "2.") and result tokens
if isMoveNumberOrResult(token) then state
else
parseAlgebraicMove(token, board, history, color) match
case None => state // unrecognised token — skip silently
case Some(move) =>
val newBoard = applyMoveToBoard(board, move, color)
val newHistory = history.addMove(move)
(newBoard, newHistory, color.opposite, acc :+ move)
moves
/** Apply a single HistoryMove to a Board, handling castling and promotion. */
private def applyMoveToBoard(board: Board, move: HistoryMove, color: Color): Board =
move.castleSide match
case Some(side) => board.withCastle(color, side)
case None =>
val (boardAfterMove, _) = board.withMove(move.from, move.to)
move.promotionPiece match
case Some(pp) =>
val pieceType = pp match
case PromotionPiece.Queen => PieceType.Queen
case PromotionPiece.Rook => PieceType.Rook
case PromotionPiece.Bishop => PieceType.Bishop
case PromotionPiece.Knight => PieceType.Knight
boardAfterMove.updated(move.to, Piece(color, pieceType))
case None => boardAfterMove
/** True for move-number tokens ("1.", "12.") and PGN result tokens. */
private def isMoveNumberOrResult(token: String): Boolean =
token.matches("""\d+\.""") ||
token == "*" ||
token == "1-0" ||
token == "0-1" ||
token == "1/2-1/2"
/** Parse a single algebraic notation token into a HistoryMove, given the current board state. */
def parseAlgebraicMove(notation: String, board: Board, history: GameHistory, color: Color): Option[HistoryMove] =
notation match
case "O-O" | "O-O+" | "O-O#" =>
val rank = if color == Color.White then Rank.R1 else Rank.R8
Some(HistoryMove(Square(File.E, rank), Square(File.G, rank), Some(CastleSide.Kingside), pieceType = PieceType.King))
case "O-O-O" | "O-O-O+" | "O-O-O#" =>
val rank = if color == Color.White then Rank.R1 else Rank.R8
Some(HistoryMove(Square(File.E, rank), Square(File.C, rank), Some(CastleSide.Queenside), pieceType = PieceType.King))
case _ =>
parseRegularMove(notation, board, history, color)
/** Parse regular algebraic notation (pawn moves, piece moves, captures, disambiguation). */
private def parseRegularMove(notation: String, board: Board, history: GameHistory, color: Color): Option[HistoryMove] =
// Strip check/mate/capture indicators and promotion suffix (e.g. =Q)
val clean = notation
.replace("+", "")
.replace("#", "")
.replace("x", "")
.replaceAll("=[NBRQ]$", "")
// The destination square is always the last two characters
if clean.length < 2 then None
else
val destStr = clean.takeRight(2)
Square.fromAlgebraic(destStr).flatMap: toSquare =>
val disambig = clean.dropRight(2) // "" | "N"|"B"|"R"|"Q"|"K" | file | rank | file+rank
// Determine required piece type: upper-case first char = piece letter; else pawn
val requiredPieceType: Option[PieceType] =
if disambig.nonEmpty && disambig.head.isUpper then charToPieceType(disambig.head)
else if clean.head.isUpper then charToPieceType(clean.head)
else Some(PieceType.Pawn)
// Collect the disambiguation hint that remains after stripping the piece letter
val hint =
if disambig.nonEmpty && disambig.head.isUpper then disambig.tail
else disambig // hint is file/rank info or empty
// Candidate source squares: pieces of `color` that can geometrically reach `toSquare`.
// We prefer pieces that can actually reach the target; if none can (positionally illegal
// PGN input), fall back to any piece of the matching type belonging to `color`.
val reachable: Set[Square] =
board.pieces.collect {
case (from, piece) if piece.color == color &&
MoveValidator.legalTargets(board, from).contains(toSquare) => from
}.toSet
val candidates: Set[Square] =
if reachable.nonEmpty then reachable
else
// Fallback for positionally-illegal but syntactically valid PGN notation:
// find any piece of `color` with the correct piece type on the board.
board.pieces.collect {
case (from, piece) if piece.color == color => from
}.toSet
// Filter by required piece type
val byPiece = candidates.filter(from =>
requiredPieceType.forall(pt => board.pieceAt(from).exists(_.pieceType == pt))
)
// Apply disambiguation hint (file letter or rank digit)
val disambiguated =
if hint.isEmpty then byPiece
else byPiece.filter(from => matchesHint(from, hint))
val promotion = extractPromotion(notation)
val movePieceType = requiredPieceType.getOrElse(PieceType.Pawn)
val moveIsCapture = notation.contains('x')
disambiguated.headOption.map(from => HistoryMove(from, toSquare, None, promotion, movePieceType, moveIsCapture))
/** True if `sq` matches a disambiguation hint (file letter, rank digit, or both). */
private def matchesHint(sq: Square, hint: String): Boolean =
hint.forall(c => if c >= 'a' && c <= 'h' then sq.file.toString.equalsIgnoreCase(c.toString)
else if c >= '1' && c <= '8' then sq.rank.ordinal == (c - '1')
else true)
/** Extract a promotion piece from a notation string containing =Q/=R/=B/=N. */
private[notation] def extractPromotion(notation: String): Option[PromotionPiece] =
val promotionPattern = """=([A-Z])""".r
promotionPattern.findFirstMatchIn(notation).flatMap { m =>
m.group(1) match
case "Q" => Some(PromotionPiece.Queen)
case "R" => Some(PromotionPiece.Rook)
case "B" => Some(PromotionPiece.Bishop)
case "N" => Some(PromotionPiece.Knight)
case _ => None
}
/** Convert a piece-letter character to a PieceType. */
private def charToPieceType(c: Char): Option[PieceType] =
c match
case 'N' => Some(PieceType.Knight)
case 'B' => Some(PieceType.Bishop)
case 'R' => Some(PieceType.Rook)
case 'Q' => Some(PieceType.Queen)
case 'K' => Some(PieceType.King)
case _ => None
// ── Strict validation helpers ─────────────────────────────────────────────
/** Walk all move tokens, failing immediately on any unresolvable or illegal move. */
private def validateMovesText(moveText: String): Either[String, List[HistoryMove]] =
val tokens = moveText.split("\\s+").filter(_.nonEmpty)
tokens.foldLeft(Right((Board.initial, GameHistory.empty, Color.White, List.empty[HistoryMove])): Either[String, (Board, GameHistory, Color, List[HistoryMove])]) {
case (acc, token) =>
acc.flatMap { case (board, history, color, moves) =>
if isMoveNumberOrResult(token) then Right((board, history, color, moves))
else
strictParseAlgebraicMove(token, board, history, color) match
case None => Left(s"Illegal or impossible move: '$token'")
case Some(move) =>
val newBoard = applyMoveToBoard(board, move, color)
val newHistory = history.addMove(move)
Right((newBoard, newHistory, color.opposite, moves :+ move))
}
}.map(_._4)
/** Strict algebraic move parse — no fallback to positionally-illegal moves. */
private def strictParseAlgebraicMove(notation: String, board: Board, history: GameHistory, color: Color): Option[HistoryMove] =
val rank = if color == Color.White then Rank.R1 else Rank.R8
notation match
case "O-O" | "O-O+" | "O-O#" =>
val dest = Square(File.G, rank)
Option.when(MoveValidator.castlingTargets(board, history, color).contains(dest))(
HistoryMove(Square(File.E, rank), dest, Some(CastleSide.Kingside), pieceType = PieceType.King)
)
case "O-O-O" | "O-O-O+" | "O-O-O#" =>
val dest = Square(File.C, rank)
Option.when(MoveValidator.castlingTargets(board, history, color).contains(dest))(
HistoryMove(Square(File.E, rank), dest, Some(CastleSide.Queenside), pieceType = PieceType.King)
)
case _ =>
strictParseRegularMove(notation, board, history, color)
/** Strict regular move parse — uses only legally reachable squares, no fallback. */
private def strictParseRegularMove(notation: String, board: Board, history: GameHistory, color: Color): Option[HistoryMove] =
val clean = notation
.replace("+", "")
.replace("#", "")
.replace("x", "")
.replaceAll("=[NBRQ]$", "")
if clean.length < 2 then None
else
val destStr = clean.takeRight(2)
Square.fromAlgebraic(destStr).flatMap { toSquare =>
val disambig = clean.dropRight(2)
val requiredPieceType: Option[PieceType] =
if disambig.nonEmpty && disambig.head.isUpper then charToPieceType(disambig.head)
else if clean.head.isUpper then charToPieceType(clean.head)
else Some(PieceType.Pawn)
val hint =
if disambig.nonEmpty && disambig.head.isUpper then disambig.tail
else disambig
// Strict: only squares from which a legal move (including en passant/castling awareness) exists.
val reachable: Set[Square] =
board.pieces.collect {
case (from, piece) if piece.color == color &&
MoveValidator.legalTargets(board, history, from).contains(toSquare) => from
}.toSet
val byPiece = reachable.filter(from =>
requiredPieceType.forall(pt => board.pieceAt(from).exists(_.pieceType == pt))
)
val disambiguated =
if hint.isEmpty then byPiece
else byPiece.filter(from => matchesHint(from, hint))
val promotion = extractPromotion(notation)
val movePieceType = requiredPieceType.getOrElse(PieceType.Pawn)
val moveIsCapture = notation.contains('x')
disambiguated.headOption.map(from => HistoryMove(from, toSquare, None, promotion, movePieceType, moveIsCapture))
}
@@ -1,21 +1,17 @@
package de.nowchess.chess.observer
import de.nowchess.api.board.{Board, Color, Square}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.api.board.{Color, Square}
import de.nowchess.api.game.GameContext
/** Base trait for all game state events.
* Events are immutable snapshots of game state changes.
*/
sealed trait GameEvent:
def board: Board
def history: GameHistory
def turn: Color
def context: GameContext
/** Fired when a move is successfully executed. */
case class MoveExecutedEvent(
board: Board,
history: GameHistory,
turn: Color,
context: GameContext,
fromSquare: String,
toSquare: String,
capturedPiece: Option[String]
@@ -23,77 +19,57 @@ case class MoveExecutedEvent(
/** Fired when the current player is in check. */
case class CheckDetectedEvent(
board: Board,
history: GameHistory,
turn: Color
context: GameContext
) extends GameEvent
/** Fired when the game reaches checkmate. */
case class CheckmateEvent(
board: Board,
history: GameHistory,
turn: Color,
context: GameContext,
winner: Color
) extends GameEvent
/** Fired when the game reaches stalemate. */
case class StalemateEvent(
board: Board,
history: GameHistory,
turn: Color
context: GameContext
) extends GameEvent
/** Fired when a move is invalid. */
case class InvalidMoveEvent(
board: Board,
history: GameHistory,
turn: Color,
context: GameContext,
reason: String
) extends GameEvent
/** Fired when a pawn reaches the back rank and the player must choose a promotion piece. */
case class PromotionRequiredEvent(
board: Board,
history: GameHistory,
turn: Color,
context: GameContext,
from: Square,
to: Square
) extends GameEvent
/** Fired when the board is reset. */
case class BoardResetEvent(
board: Board,
history: GameHistory,
turn: Color
context: GameContext
) extends GameEvent
/** Fired after any move where the half-move clock reaches 100 — the 50-move rule is now claimable. */
case class FiftyMoveRuleAvailableEvent(
board: Board,
history: GameHistory,
turn: Color
context: GameContext
) extends GameEvent
/** Fired when a player successfully claims a draw under the 50-move rule. */
case class DrawClaimedEvent(
board: Board,
history: GameHistory,
turn: Color
context: GameContext
) extends GameEvent
/** Fired when a move is undone, carrying PGN notation of the reversed move. */
case class MoveUndoneEvent(
board: Board,
history: GameHistory,
turn: Color,
context: GameContext,
pgnNotation: String
) extends GameEvent
/** Fired when a previously undone move is redone, carrying PGN notation of the replayed move. */
case class MoveRedoneEvent(
board: Board,
history: GameHistory,
turn: Color,
context: GameContext,
pgnNotation: String,
fromSquare: String,
toSquare: String,
@@ -102,9 +78,7 @@ case class MoveRedoneEvent(
/** Fired after a PGN string is successfully loaded and all moves are replayed into history. */
case class PgnLoadedEvent(
board: Board,
history: GameHistory,
turn: Color
context: GameContext
) extends GameEvent
/** Observer trait: implement to receive game state updates. */
@@ -1,18 +0,0 @@
package de.nowchess.chess.view
import de.nowchess.api.board.{Color, Piece, PieceType}
extension (p: Piece)
def unicode: String = (p.color, p.pieceType) match
case (Color.White, PieceType.King) => "\u2654"
case (Color.White, PieceType.Queen) => "\u2655"
case (Color.White, PieceType.Rook) => "\u2656"
case (Color.White, PieceType.Bishop) => "\u2657"
case (Color.White, PieceType.Knight) => "\u2658"
case (Color.White, PieceType.Pawn) => "\u2659"
case (Color.Black, PieceType.King) => "\u265A"
case (Color.Black, PieceType.Queen) => "\u265B"
case (Color.Black, PieceType.Rook) => "\u265C"
case (Color.Black, PieceType.Bishop) => "\u265D"
case (Color.Black, PieceType.Knight) => "\u265E"
case (Color.Black, PieceType.Pawn) => "\u265F"
@@ -1,28 +0,0 @@
package de.nowchess.chess.view
import de.nowchess.api.board.{Board, Color, File, Rank, Square}
object Renderer:
private val AnsiReset = "\u001b[0m"
private val AnsiLightSquare = "\u001b[48;5;223m" // warm beige
private val AnsiDarkSquare = "\u001b[48;5;130m" // brown
private val AnsiWhitePiece = "\u001b[97m" // bright white text
private val AnsiBlackPiece = "\u001b[30m" // black text
def render(board: Board): String =
val rows = (0 until 8).reverse.map { rank =>
val cells = (0 until 8).map { file =>
val sq = Square(File.values(file), Rank.values(rank))
val isLightSq = (file + rank) % 2 != 0
val bgColor = if isLightSq then AnsiLightSquare else AnsiDarkSquare
board.pieceAt(sq) match
case Some(piece) =>
val fgColor = if piece.color == Color.White then AnsiWhitePiece else AnsiBlackPiece
s"$bgColor$fgColor ${piece.unicode} $AnsiReset"
case None =>
s"$bgColor $AnsiReset"
}.mkString
s"${rank + 1} $cells ${rank + 1}"
}.mkString("\n")
s" a b c d e f g h\n$rows\n a b c d e f g h\n"
@@ -1,216 +1,148 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, File, Rank, Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.api.board.{Square, File, Rank}
import de.nowchess.api.game.GameContext
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class CommandInvokerBranchTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
// ──── Helper: Command that always fails ────
private case class FailingCommand() extends Command:
override def execute(): Boolean = false
override def undo(): Boolean = false
override def description: String = "Failing command"
// ──── Helper: Command that conditionally fails on undo or execute ────
private case class ConditionalFailCommand(var shouldFailOnUndo: Boolean = false, var shouldFailOnExecute: Boolean = false) extends Command:
override def execute(): Boolean = !shouldFailOnExecute
override def undo(): Boolean = !shouldFailOnUndo
override def description: String = "Conditional fail"
private def createMoveCommand(from: Square, to: Square, executeSucceeds: Boolean = true): MoveCommand =
val cmd = MoveCommand(
MoveCommand(
from = from,
to = to,
moveResult = if executeSucceeds then Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)) else None,
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
moveResult = if executeSucceeds then Some(MoveResult.Successful(GameContext.initial, None)) else None,
previousContext = Some(GameContext.initial)
)
cmd
// ──── BRANCH: execute() returns false ────
test("CommandInvoker.execute() with failing command returns false"):
test("execute rejects failing commands and keeps history unchanged"):
val invoker = new CommandInvoker()
val cmd = FailingCommand()
invoker.execute(cmd) shouldBe false
invoker.history.size shouldBe 0
invoker.getCurrentIndex shouldBe -1
test("CommandInvoker.execute() does not add failed command to history"):
val invoker = new CommandInvoker()
val failingCmd = FailingCommand()
val successCmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(failingCmd) shouldBe false
invoker.history.size shouldBe 0
invoker.execute(successCmd) shouldBe true
invoker.history.size shouldBe 1
invoker.history(0) shouldBe successCmd
invoker.history.head shouldBe successCmd
// ──── BRANCH: undo() with invalid index (currentIndex < 0) ────
test("CommandInvoker.undo() returns false when currentIndex < 0"):
val invoker = new CommandInvoker()
// currentIndex starts at -1
invoker.undo() shouldBe false
test("undo redo and history trimming cover all command state transitions"):
{
val invoker = new CommandInvoker()
invoker.undo() shouldBe false
invoker.canUndo shouldBe false
invoker.undo() shouldBe false
}
test("CommandInvoker.undo() returns false when empty history"):
val invoker = new CommandInvoker()
invoker.canUndo shouldBe false
invoker.undo() shouldBe false
{
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
invoker.execute(cmd1)
invoker.execute(cmd2)
invoker.undo()
invoker.undo()
invoker.undo() shouldBe false
}
// ──── BRANCH: undo() with invalid index (currentIndex >= size) ────
test("CommandInvoker.undo() returns false when currentIndex >= history size"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
invoker.execute(cmd1)
invoker.execute(cmd2)
// currentIndex now = 1, history.size = 2
invoker.undo() // currentIndex becomes 0
invoker.undo() // currentIndex becomes -1
invoker.undo() // currentIndex still -1, should fail
{
val invoker = new CommandInvoker()
val failingUndoCmd = ConditionalFailCommand(shouldFailOnUndo = true)
invoker.execute(failingUndoCmd) shouldBe true
invoker.canUndo shouldBe true
invoker.undo() shouldBe false
invoker.getCurrentIndex shouldBe 0
}
// ──── BRANCH: undo() command returns false ────
test("CommandInvoker.undo() returns false when command.undo() fails"):
val invoker = new CommandInvoker()
val failingCmd = ConditionalFailCommand(shouldFailOnUndo = true)
invoker.execute(failingCmd) shouldBe true
invoker.canUndo shouldBe true
invoker.undo() shouldBe false
// Index should not change when undo fails
invoker.getCurrentIndex shouldBe 0
{
val invoker = new CommandInvoker()
val successUndoCmd = ConditionalFailCommand()
invoker.execute(successUndoCmd) shouldBe true
invoker.undo() shouldBe true
invoker.getCurrentIndex shouldBe -1
}
test("CommandInvoker.undo() returns true when command.undo() succeeds"):
val invoker = new CommandInvoker()
val successCmd = ConditionalFailCommand(shouldFailOnUndo = false)
invoker.execute(successCmd) shouldBe true
invoker.undo() shouldBe true
invoker.getCurrentIndex shouldBe -1
{
val invoker = new CommandInvoker()
invoker.redo() shouldBe false
}
// ──── BRANCH: redo() with invalid index (currentIndex + 1 >= size) ────
test("CommandInvoker.redo() returns false when nothing to redo"):
val invoker = new CommandInvoker()
invoker.redo() shouldBe false
{
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
invoker.canRedo shouldBe false
invoker.redo() shouldBe false
}
test("CommandInvoker.redo() returns false when at end of history"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
// currentIndex = 0, history.size = 1
invoker.canRedo shouldBe false
invoker.redo() shouldBe false
{
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val redoFailCmd = ConditionalFailCommand()
invoker.execute(cmd1)
invoker.execute(redoFailCmd)
invoker.undo()
invoker.canRedo shouldBe true
redoFailCmd.shouldFailOnExecute = true
invoker.redo() shouldBe false
invoker.getCurrentIndex shouldBe 0
}
test("CommandInvoker.redo() returns false when currentIndex + 1 >= size"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
invoker.execute(cmd1)
invoker.execute(cmd2)
// currentIndex = 1, size = 2, currentIndex + 1 = 2, so 2 < 2 is false
invoker.canRedo shouldBe false
invoker.redo() shouldBe false
{
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd) shouldBe true
invoker.undo() shouldBe true
invoker.redo() shouldBe true
invoker.getCurrentIndex shouldBe 0
}
// ──── BRANCH: redo() command returns false ────
test("CommandInvoker.redo() returns false when command.execute() fails"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val redoFailCmd = ConditionalFailCommand(shouldFailOnExecute = false) // Succeeds on first execute
invoker.execute(cmd1)
invoker.execute(redoFailCmd) // Succeeds and added to history
invoker.undo()
// currentIndex = 0, redoFailCmd is at index 1
invoker.canRedo shouldBe true
// Now modify to fail on next execute (redo)
redoFailCmd.shouldFailOnExecute = true
invoker.redo() shouldBe false
// currentIndex should not change
invoker.getCurrentIndex shouldBe 0
test("CommandInvoker.redo() returns true when command.execute() succeeds"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd) shouldBe true
invoker.undo() shouldBe true
invoker.redo() shouldBe true
invoker.getCurrentIndex shouldBe 0
// ──── BRANCH: execute() with redo history discarding (while loop) ────
test("CommandInvoker.execute() discards redo history via while loop"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
val cmd3 = createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
invoker.execute(cmd1)
invoker.execute(cmd2)
// currentIndex = 1, size = 2
invoker.undo()
// currentIndex = 0, size = 2
// Redo history exists: cmd2 is at index 1
invoker.canRedo shouldBe true
invoker.execute(cmd3)
// while loop should discard cmd2
invoker.canRedo shouldBe false
invoker.history.size shouldBe 2
invoker.history(1) shouldBe cmd3
test("CommandInvoker.execute() discards multiple redo commands"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
val cmd3 = createMoveCommand(sq(File.G, Rank.R1), sq(File.F, Rank.R3))
val cmd4 = createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
invoker.execute(cmd1)
invoker.execute(cmd2)
invoker.execute(cmd3)
invoker.execute(cmd4)
// currentIndex = 3, size = 4
invoker.undo()
invoker.undo()
// currentIndex = 1, size = 4
// Redo history: cmd3 (idx 2), cmd4 (idx 3)
invoker.canRedo shouldBe true
val newCmd = createMoveCommand(sq(File.B, Rank.R2), sq(File.B, Rank.R4))
invoker.execute(newCmd)
// While loop should discard indices 2 and 3 (cmd3 and cmd4)
invoker.history.size shouldBe 3
invoker.canRedo shouldBe false
// ──── BRANCH: execute() with no redo history to discard ────
test("CommandInvoker.execute() with no redo history (while condition false)"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
invoker.execute(cmd1)
invoker.execute(cmd2)
// currentIndex = 1, size = 2
// currentIndex < size - 1 is 1 < 1 which is false, so while loop doesn't run
invoker.canRedo shouldBe false
val cmd3 = createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
invoker.execute(cmd3) // While loop condition should be false, no iterations
invoker.history.size shouldBe 3
{
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
val cmd3 = createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
invoker.execute(cmd1)
invoker.execute(cmd2)
invoker.undo()
invoker.canRedo shouldBe true
invoker.execute(cmd3)
invoker.canRedo shouldBe false
invoker.history.size shouldBe 2
invoker.history(1) shouldBe cmd3
}
{
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
val cmd3 = createMoveCommand(sq(File.G, Rank.R1), sq(File.F, Rank.R3))
val cmd4 = createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
invoker.execute(cmd1)
invoker.execute(cmd2)
invoker.execute(cmd3)
invoker.execute(cmd4)
invoker.undo()
invoker.undo()
invoker.canRedo shouldBe true
val newCmd = createMoveCommand(sq(File.B, Rank.R2), sq(File.B, Rank.R4))
invoker.execute(newCmd)
invoker.history.size shouldBe 3
invoker.canRedo shouldBe false
}
@@ -1,81 +1,47 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, File, Rank, Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.api.board.{Square, File, Rank}
import de.nowchess.api.game.GameContext
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class CommandInvokerTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
private def createMoveCommand(from: Square, to: Square): MoveCommand =
MoveCommand(
from = from,
to = to,
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)),
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
moveResult = Some(MoveResult.Successful(GameContext.initial, None)),
previousContext = Some(GameContext.initial)
)
test("CommandInvoker executes a command and adds it to history"):
test("execute appends commands and updates index"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd) shouldBe true
invoker.history.size shouldBe 1
invoker.getCurrentIndex shouldBe 0
test("CommandInvoker executes multiple commands in sequence"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
invoker.execute(cmd1) shouldBe true
invoker.execute(cmd2) shouldBe true
invoker.history.size shouldBe 2
invoker.getCurrentIndex shouldBe 1
test("CommandInvoker.canUndo returns false when empty"):
val invoker = new CommandInvoker()
invoker.canUndo shouldBe false
test("CommandInvoker.canUndo returns true after execution"):
test("undo and redo update index and availability flags"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.canUndo shouldBe false
invoker.execute(cmd)
invoker.canUndo shouldBe true
test("CommandInvoker.undo decrements current index"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
invoker.getCurrentIndex shouldBe 0
invoker.undo() shouldBe true
invoker.getCurrentIndex shouldBe -1
test("CommandInvoker.canRedo returns true after undo"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
invoker.undo()
invoker.canRedo shouldBe true
test("CommandInvoker.redo re-executes a command"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
invoker.undo() shouldBe true
invoker.redo() shouldBe true
invoker.getCurrentIndex shouldBe 0
test("CommandInvoker.canUndo returns false when at beginning"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
invoker.undo()
invoker.canUndo shouldBe false
test("CommandInvoker clear removes all history"):
test("clear removes full history and resets index"):
val invoker = new CommandInvoker()
val cmd = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
invoker.execute(cmd)
@@ -83,7 +49,7 @@ class CommandInvokerTest extends AnyFunSuite with Matchers:
invoker.history.size shouldBe 0
invoker.getCurrentIndex shouldBe -1
test("CommandInvoker discards all history when executing after undoing all"):
test("execute after undo discards redo history"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
@@ -91,33 +57,11 @@ class CommandInvokerTest extends AnyFunSuite with Matchers:
invoker.execute(cmd1)
invoker.execute(cmd2)
invoker.undo()
invoker.undo()
// After undoing twice, we're at the beginning (before any commands)
invoker.getCurrentIndex shouldBe -1
invoker.canRedo shouldBe true
// Executing a new command from the beginning discards all redo history
invoker.execute(cmd3)
invoker.canRedo shouldBe false
invoker.history.size shouldBe 1
invoker.history(0) shouldBe cmd3
invoker.getCurrentIndex shouldBe 0
test("CommandInvoker discards redo history when executing mid-history"):
val invoker = new CommandInvoker()
val cmd1 = createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val cmd2 = createMoveCommand(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
val cmd3 = createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
invoker.execute(cmd1)
invoker.execute(cmd2)
invoker.undo()
// After one undo, we're at the end of cmd1
invoker.getCurrentIndex shouldBe 0
invoker.canRedo shouldBe true
// Executing a new command discards cmd2 (the redo history)
invoker.execute(cmd3)
invoker.canRedo shouldBe false
invoker.history.size shouldBe 2
invoker.history(0) shouldBe cmd1
invoker.history.head shouldBe cmd1
invoker.history(1) shouldBe cmd3
invoker.getCurrentIndex shouldBe 1
@@ -1,131 +0,0 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, File, Rank, Board, Color}
import de.nowchess.chess.logic.GameHistory
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
import scala.collection.mutable
class CommandInvokerThreadSafetyTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
private def createMoveCommand(from: Square, to: Square): MoveCommand =
MoveCommand(
from = from,
to = to,
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)),
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
)
test("CommandInvoker is thread-safe for concurrent execute and history reads"):
val invoker = new CommandInvoker()
@volatile var raceDetected = false
val exceptions = mutable.ListBuffer[Exception]()
// Thread 1: executes commands
val executorThread = new Thread(new Runnable {
def run(): Unit = {
try {
for i <- 1 to 1000 do
val cmd = createMoveCommand(
sq(File.E, Rank.R2),
sq(File.E, Rank.R4)
)
invoker.execute(cmd)
} catch {
case e: Exception =>
exceptions += e
raceDetected = true
}
}
})
// Thread 2: reads history during execution
val readerThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 1000 do
val _ = invoker.history
val _ = invoker.getCurrentIndex
Thread.sleep(0) // Yield to increase contention
} catch {
case e: Exception =>
exceptions += e
raceDetected = true
}
}
})
executorThread.start()
readerThread.start()
executorThread.join()
readerThread.join()
exceptions.isEmpty shouldBe true
raceDetected shouldBe false
test("CommandInvoker is thread-safe for concurrent execute, undo, and redo"):
val invoker = new CommandInvoker()
@volatile var raceDetected = false
val exceptions = mutable.ListBuffer[Exception]()
// Pre-populate with some commands
for _ <- 1 to 5 do
invoker.execute(createMoveCommand(sq(File.E, Rank.R2), sq(File.E, Rank.R4)))
// Thread 1: executes new commands
val executorThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500 do
invoker.execute(createMoveCommand(sq(File.D, Rank.R2), sq(File.D, Rank.R4)))
} catch {
case e: Exception =>
exceptions += e
raceDetected = true
}
}
})
// Thread 2: undoes commands
val undoThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500 do
if invoker.canUndo then
invoker.undo()
} catch {
case e: Exception =>
exceptions += e
raceDetected = true
}
}
})
// Thread 3: redoes commands
val redoThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500 do
if invoker.canRedo then
invoker.redo()
} catch {
case e: Exception =>
exceptions += e
raceDetected = true
}
}
})
executorThread.start()
undoThread.start()
redoThread.start()
executorThread.join()
undoThread.join()
redoThread.join()
exceptions.isEmpty shouldBe true
raceDetected shouldBe false
@@ -1,52 +1,24 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.api.game.GameContext
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class CommandTest extends AnyFunSuite with Matchers:
test("QuitCommand can be created"):
test("QuitCommand properties and behavior"):
val cmd = QuitCommand()
cmd shouldNot be(null)
test("QuitCommand execute returns true"):
val cmd = QuitCommand()
cmd.execute() shouldBe true
test("QuitCommand undo returns false (cannot undo quit)"):
val cmd = QuitCommand()
cmd.undo() shouldBe false
test("QuitCommand description"):
val cmd = QuitCommand()
cmd.description shouldBe "Quit game"
test("ResetCommand with no prior state"):
val cmd = ResetCommand()
cmd.execute() shouldBe true
cmd.undo() shouldBe false
test("ResetCommand with prior state can undo"):
val cmd = ResetCommand(
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
)
cmd.execute() shouldBe true
cmd.undo() shouldBe true
test("ResetCommand with partial state cannot undo"):
val cmd = ResetCommand(
previousBoard = Some(Board.initial),
previousHistory = None, // missing
previousTurn = Some(Color.White)
)
cmd.execute() shouldBe true
cmd.undo() shouldBe false
test("ResetCommand description"):
val cmd = ResetCommand()
cmd.description shouldBe "Reset board"
test("ResetCommand behavior depends on previousContext"):
val noState = ResetCommand()
noState.execute() shouldBe true
noState.undo() shouldBe false
noState.description shouldBe "Reset board"
val withState = ResetCommand(previousContext = Some(GameContext.initial))
withState.execute() shouldBe true
withState.undo() shouldBe true
@@ -1,65 +0,0 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, File, Rank, Board, Color}
import de.nowchess.chess.logic.GameHistory
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class MoveCommandImmutabilityTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
test("MoveCommand should be immutable - fields cannot be mutated after creation"):
val cmd1 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4)
)
// Create second command with filled state
val result = MoveResult.Successful(Board.initial, GameHistory.empty, Color.Black, None)
val cmd2 = cmd1.copy(
moveResult = Some(result),
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
)
// Original should be unchanged
cmd1.moveResult shouldBe None
cmd1.previousBoard shouldBe None
cmd1.previousHistory shouldBe None
cmd1.previousTurn shouldBe None
// New should have values
cmd2.moveResult shouldBe Some(result)
cmd2.previousBoard shouldBe Some(Board.initial)
cmd2.previousHistory shouldBe Some(GameHistory.empty)
cmd2.previousTurn shouldBe Some(Color.White)
test("MoveCommand equals and hashCode respect immutability"):
val cmd1 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = None,
previousBoard = None,
previousHistory = None,
previousTurn = None
)
val cmd2 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = None,
previousBoard = None,
previousHistory = None,
previousTurn = None
)
// Same values should be equal
cmd1 shouldBe cmd2
cmd1.hashCode shouldBe cmd2.hashCode
// Hash should be consistent (required for use as map keys)
val hash1 = cmd1.hashCode
val hash2 = cmd1.hashCode
hash1 shouldBe hash2
@@ -0,0 +1,70 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, File, Rank}
import de.nowchess.api.game.GameContext
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class MoveCommandTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
test("MoveCommand defaults to empty optional state and false execute/undo"):
val cmd = MoveCommand(from = sq(File.E, Rank.R2), to = sq(File.E, Rank.R4))
cmd.moveResult shouldBe None
cmd.previousContext shouldBe None
cmd.execute() shouldBe false
cmd.undo() shouldBe false
cmd.description shouldBe "Move from e2 to e4"
test("MoveCommand execute/undo succeed when state is present"):
val executable = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(GameContext.initial, None))
)
executable.execute() shouldBe true
val undoable = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(GameContext.initial, None)),
previousContext = Some(GameContext.initial)
)
undoable.undo() shouldBe true
test("MoveCommand is immutable and preserves equality/hash semantics"):
val cmd1 = MoveCommand(from = sq(File.E, Rank.R2), to = sq(File.E, Rank.R4))
val result = MoveResult.Successful(GameContext.initial, None)
val cmd2 = cmd1.copy(
moveResult = Some(result),
previousContext = Some(GameContext.initial)
)
cmd1.moveResult shouldBe None
cmd1.previousContext shouldBe None
cmd2.moveResult shouldBe Some(result)
cmd2.previousContext shouldBe Some(GameContext.initial)
val eq1 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = None,
previousContext = None
)
val eq2 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = None,
previousContext = None
)
eq1 shouldBe eq2
eq1.hashCode shouldBe eq2.hashCode
val hash1 = eq1.hashCode
val hash2 = eq1.hashCode
hash1 shouldBe hash2
@@ -1,526 +0,0 @@
package de.nowchess.chess.controller
import de.nowchess.api.board.*
import de.nowchess.api.game.CastlingRights
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{CastleSide, GameHistory}
import de.nowchess.chess.notation.FenParser
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameControllerTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
private def processMove(board: Board, history: GameHistory, turn: Color, raw: String): MoveResult =
GameController.processMove(board, history, turn, raw)
private def castlingRights(history: GameHistory, color: Color): CastlingRights =
de.nowchess.chess.logic.CastlingRightsCalculator.deriveCastlingRights(history, color)
// ──── processMove ────────────────────────────────────────────────────
test("processMove: 'quit' input returns Quit"):
processMove(Board.initial, GameHistory.empty, Color.White, "quit") shouldBe MoveResult.Quit
test("processMove: 'q' input returns Quit"):
processMove(Board.initial, GameHistory.empty, Color.White, "q") shouldBe MoveResult.Quit
test("processMove: quit with surrounding whitespace returns Quit"):
processMove(Board.initial, GameHistory.empty, Color.White, " quit ") shouldBe MoveResult.Quit
test("processMove: unparseable input returns InvalidFormat"):
processMove(Board.initial, GameHistory.empty, Color.White, "xyz") shouldBe MoveResult.InvalidFormat("xyz")
test("processMove: valid format but empty square returns NoPiece"):
// E3 is empty in the initial position
processMove(Board.initial, GameHistory.empty, Color.White, "e3e4") shouldBe MoveResult.NoPiece
test("processMove: piece of wrong color returns WrongColor"):
// E7 has a Black pawn; it is White's turn
processMove(Board.initial, GameHistory.empty, Color.White, "e7e6") shouldBe MoveResult.WrongColor
test("processMove: geometrically illegal move returns IllegalMove"):
// White pawn at E2 cannot jump three squares to E5
processMove(Board.initial, GameHistory.empty, Color.White, "e2e5") shouldBe MoveResult.IllegalMove
test("processMove: move that leaves own king in check returns IllegalMove"):
// White King E1 is in check from Black Rook E8. Moving the D2 pawn is
// geometrically legal but does not resolve the check — must be rejected.
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.D, Rank.R2) -> Piece.WhitePawn,
sq(File.E, Rank.R8) -> Piece.BlackRook,
sq(File.A, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "d2d4") shouldBe MoveResult.IllegalMove
test("processMove: move that resolves check is allowed"):
// White King E1 is in check from Black Rook E8 along the E-file.
// White Rook A5 interposes at E5 — resolves the check, no new check on Black King A8.
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R5) -> Piece.WhiteRook,
sq(File.E, Rank.R8) -> Piece.BlackRook,
sq(File.A, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "a5e5") match
case _: MoveResult.Moved => succeed
case other => fail(s"Expected Moved, got $other")
test("processMove: legal pawn move returns Moved with updated board and flipped turn"):
processMove(Board.initial, GameHistory.empty, Color.White, "e2e4") match
case MoveResult.Moved(newBoard, newHistory, captured, newTurn) =>
newBoard.pieceAt(sq(File.E, Rank.R4)) shouldBe Some(Piece.WhitePawn)
newBoard.pieceAt(sq(File.E, Rank.R2)) shouldBe None
captured shouldBe None
newTurn shouldBe Color.Black
case other => fail(s"Expected Moved, got $other")
test("processMove: legal capture returns Moved with the captured piece"):
val board = Board(Map(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R6) -> Piece.BlackPawn,
sq(File.H, Rank.R1) -> Piece.BlackKing,
sq(File.H, Rank.R8) -> Piece.WhiteKing
))
processMove(board, GameHistory.empty, Color.White, "e5d6") match
case MoveResult.Moved(newBoard, newHistory, captured, newTurn) =>
captured shouldBe Some(Piece.BlackPawn)
newBoard.pieceAt(sq(File.D, Rank.R6)) shouldBe Some(Piece.WhitePawn)
newTurn shouldBe Color.Black
case other => fail(s"Expected Moved, got $other")
// ──── processMove: check / checkmate / stalemate ─────────────────────
test("processMove: legal move that delivers check returns MovedInCheck"):
// White Ra1, Ka3; Black Kh8 — White plays Ra1-Ra8, Ra8 attacks rank 8 putting Kh8 in check
// Kh8 can escape to g7/g8/h7 so this is InCheck, not Mated
val b = Board(Map(
sq(File.A, Rank.R1) -> Piece.WhiteRook,
sq(File.C, Rank.R3) -> Piece.WhiteKing,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "a1a8") match
case MoveResult.MovedInCheck(_, _, _, newTurn) => newTurn shouldBe Color.Black
case other => fail(s"Expected MovedInCheck, got $other")
test("processMove: legal move that results in checkmate returns Checkmate"):
// White Qa1, Ka6; Black Ka8 — White plays Qa1-Qh8 (diagonal a1→h8)
// After Qh8: White Qh8 + Ka6 vs Black Ka8 = checkmate (spec-verified position)
// Qa1 does NOT currently attack Ka8 — path along file A is blocked by Ka6
val b = Board(Map(
sq(File.A, Rank.R1) -> Piece.WhiteQueen,
sq(File.A, Rank.R6) -> Piece.WhiteKing,
sq(File.A, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "a1h8") match
case MoveResult.Checkmate(winner) => winner shouldBe Color.White
case other => fail(s"Expected Checkmate(White), got $other")
test("processMove: legal move that results in stalemate returns Stalemate"):
// White Qb1, Kc6; Black Ka8 — White plays Qb1-Qb6
// After Qb6: White Qb6 + Kc6 vs Black Ka8 = stalemate (spec-verified position)
val b = Board(Map(
sq(File.B, Rank.R1) -> Piece.WhiteQueen,
sq(File.C, Rank.R6) -> Piece.WhiteKing,
sq(File.A, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "b1b6") match
case MoveResult.Stalemate => succeed
case other => fail(s"Expected Stalemate, got $other")
// ──── castling execution ─────────────────────────────────────────────
test("processMove: e1g1 returns Moved with king on g1 and rook on f1"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "e1g1") match
case MoveResult.Moved(newBoard, newHistory, captured, newTurn) =>
newBoard.pieceAt(sq(File.G, Rank.R1)) shouldBe Some(Piece.WhiteKing)
newBoard.pieceAt(sq(File.F, Rank.R1)) shouldBe Some(Piece.WhiteRook)
newBoard.pieceAt(sq(File.E, Rank.R1)) shouldBe None
newBoard.pieceAt(sq(File.H, Rank.R1)) shouldBe None
captured shouldBe None
newTurn shouldBe Color.Black
case other => fail(s"Expected Moved, got $other")
test("processMove: e1c1 returns Moved with king on c1 and rook on d1"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "e1c1") match
case MoveResult.Moved(newBoard, _, _, _) =>
newBoard.pieceAt(sq(File.C, Rank.R1)) shouldBe Some(Piece.WhiteKing)
newBoard.pieceAt(sq(File.D, Rank.R1)) shouldBe Some(Piece.WhiteRook)
case other => fail(s"Expected Moved, got $other")
// ──── rights revocation ──────────────────────────────────────────────
test("processMove: e1g1 revokes both white castling rights"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "e1g1") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White) shouldBe CastlingRights.None
case other => fail(s"Expected Moved, got $other")
test("processMove: moving rook from h1 revokes white kingside right"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "h1h4") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White).kingSide shouldBe false
castlingRights(newHistory, Color.White).queenSide shouldBe true
case MoveResult.MovedInCheck(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White).kingSide shouldBe false
castlingRights(newHistory, Color.White).queenSide shouldBe true
case other => fail(s"Expected Moved or MovedInCheck, got $other")
test("processMove: moving king from e1 revokes both white rights"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "e1e2") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White) shouldBe CastlingRights.None
case other => fail(s"Expected Moved, got $other")
test("processMove: enemy capture on h1 revokes white kingside right"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R2) -> Piece.BlackRook,
sq(File.A, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.Black, "h2h1") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White).kingSide shouldBe false
case MoveResult.MovedInCheck(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White).kingSide shouldBe false
case other => fail(s"Expected Moved or MovedInCheck, got $other")
test("processMove: castle attempt when rights revoked returns IllegalMove"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
val history = GameHistory.empty.addMove(sq(File.E, Rank.R1), sq(File.E, Rank.R2)).addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R1))
processMove(b, history, Color.White, "e1g1") shouldBe MoveResult.IllegalMove
test("processMove: castle attempt when rook not on home square returns IllegalMove"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.G, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.White, "e1g1") shouldBe MoveResult.IllegalMove
test("processMove: moving king from e8 revokes both black rights"):
val b = Board(Map(
sq(File.E, Rank.R8) -> Piece.BlackKing,
sq(File.H, Rank.R1) -> Piece.WhiteKing
))
processMove(b, GameHistory.empty, Color.Black, "e8e7") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.Black) shouldBe CastlingRights.None
case MoveResult.MovedInCheck(_, newHistory, _, _) =>
castlingRights(newHistory, Color.Black) shouldBe CastlingRights.None
case other => fail(s"Expected Moved or MovedInCheck, got $other")
test("processMove: moving rook from a8 revokes black queenside right"):
val b = Board(Map(
sq(File.E, Rank.R8) -> Piece.BlackKing,
sq(File.A, Rank.R8) -> Piece.BlackRook,
sq(File.H, Rank.R1) -> Piece.WhiteKing
))
processMove(b, GameHistory.empty, Color.Black, "a8a1") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.Black).queenSide shouldBe false
castlingRights(newHistory, Color.Black).kingSide shouldBe true
case MoveResult.MovedInCheck(_, newHistory, _, _) =>
castlingRights(newHistory, Color.Black).queenSide shouldBe false
castlingRights(newHistory, Color.Black).kingSide shouldBe true
case other => fail(s"Expected Moved or MovedInCheck, got $other")
test("processMove: moving rook from h8 revokes black kingside right"):
val b = Board(Map(
sq(File.E, Rank.R8) -> Piece.BlackKing,
sq(File.H, Rank.R8) -> Piece.BlackRook,
sq(File.A, Rank.R1) -> Piece.WhiteKing
))
processMove(b, GameHistory.empty, Color.Black, "h8h4") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.Black).kingSide shouldBe false
castlingRights(newHistory, Color.Black).queenSide shouldBe true
case MoveResult.MovedInCheck(_, newHistory, _, _) =>
castlingRights(newHistory, Color.Black).kingSide shouldBe false
castlingRights(newHistory, Color.Black).queenSide shouldBe true
case other => fail(s"Expected Moved or MovedInCheck, got $other")
test("processMove: enemy capture on a1 revokes white queenside right"):
val b = Board(Map(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R1) -> Piece.WhiteRook,
sq(File.A, Rank.R2) -> Piece.BlackRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
))
processMove(b, GameHistory.empty, Color.Black, "a2a1") match
case MoveResult.Moved(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White).queenSide shouldBe false
case MoveResult.MovedInCheck(_, newHistory, _, _) =>
castlingRights(newHistory, Color.White).queenSide shouldBe false
case other => fail(s"Expected Moved or MovedInCheck, got $other")
// ──── en passant ────────────────────────────────────────────────────────
test("en passant capture removes the captured pawn from the board"):
// Setup: white pawn e5, black pawn just double-pushed to d5 (ep target = d6)
val b = Board(Map(
Square(File.E, Rank.R5) -> Piece.WhitePawn,
Square(File.D, Rank.R5) -> Piece.BlackPawn,
Square(File.E, Rank.R1) -> Piece.WhiteKing,
Square(File.E, Rank.R8) -> Piece.BlackKing
))
val h = GameHistory.empty.addMove(Square(File.D, Rank.R7), Square(File.D, Rank.R5))
val result = GameController.processMove(b, h, Color.White, "e5d6")
result match
case MoveResult.Moved(newBoard, _, captured, _) =>
newBoard.pieceAt(Square(File.D, Rank.R5)) shouldBe None // captured pawn removed
newBoard.pieceAt(Square(File.D, Rank.R6)) shouldBe Some(Piece.WhitePawn) // capturing pawn placed
captured shouldBe Some(Piece.BlackPawn)
case other => fail(s"Expected Moved but got $other")
test("en passant capture by black removes the captured white pawn"):
// Setup: black pawn d4, white pawn just double-pushed to e4 (ep target = e3)
val b = Board(Map(
Square(File.D, Rank.R4) -> Piece.BlackPawn,
Square(File.E, Rank.R4) -> Piece.WhitePawn,
Square(File.E, Rank.R8) -> Piece.BlackKing,
Square(File.E, Rank.R1) -> Piece.WhiteKing
))
val h = GameHistory.empty.addMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4))
val result = GameController.processMove(b, h, Color.Black, "d4e3")
result match
case MoveResult.Moved(newBoard, _, captured, _) =>
newBoard.pieceAt(Square(File.E, Rank.R4)) shouldBe None // captured pawn removed
newBoard.pieceAt(Square(File.E, Rank.R3)) shouldBe Some(Piece.BlackPawn) // capturing pawn placed
captured shouldBe Some(Piece.WhitePawn)
case other => fail(s"Expected Moved but got $other")
// ──── pawn promotion detection ───────────────────────────────────────────
test("processMove detects white pawn reaching R8 and returns PromotionRequired"):
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = GameController.processMove(board, GameHistory.empty, Color.White, "e7e8")
result should matchPattern { case _: MoveResult.PromotionRequired => }
result match
case MoveResult.PromotionRequired(from, to, _, _, _, turn) =>
from should be (sq(File.E, Rank.R7))
to should be (sq(File.E, Rank.R8))
turn should be (Color.White)
case _ => fail("Expected PromotionRequired")
test("processMove detects black pawn reaching R1 and returns PromotionRequired"):
val board = FenParser.parseBoard("8/8/8/8/4K3/8/4p3/8").get
val result = GameController.processMove(board, GameHistory.empty, Color.Black, "e2e1")
result should matchPattern { case _: MoveResult.PromotionRequired => }
result match
case MoveResult.PromotionRequired(from, to, _, _, _, turn) =>
from should be (sq(File.E, Rank.R2))
to should be (sq(File.E, Rank.R1))
turn should be (Color.Black)
case _ => fail("Expected PromotionRequired")
test("processMove detects pawn capturing to back rank as PromotionRequired with captured piece"):
val board = FenParser.parseBoard("3q4/4P3/8/8/8/8/8/8").get
val result = GameController.processMove(board, GameHistory.empty, Color.White, "e7d8")
result should matchPattern { case _: MoveResult.PromotionRequired => }
result match
case MoveResult.PromotionRequired(_, _, _, _, captured, _) =>
captured should be (Some(Piece(Color.Black, PieceType.Queen)))
case _ => fail("Expected PromotionRequired")
// ──── completePromotion ──────────────────────────────────────────────────
test("completePromotion applies move and places queen"):
// Black king on h1: not attacked by queen on e8 (different file, rank, and diagonals)
val board = FenParser.parseBoard("8/4P3/8/8/8/8/8/7k").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R7), sq(File.E, Rank.R8),
PromotionPiece.Queen, Color.White
)
result should matchPattern { case _: MoveResult.Moved => }
result match
case MoveResult.Moved(newBoard, newHistory, _, _) =>
newBoard.pieceAt(sq(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Queen)))
newBoard.pieceAt(sq(File.E, Rank.R7)) should be (None)
newHistory.moves should have length 1
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Queen))
case _ => fail("Expected Moved")
test("completePromotion with rook underpromotion"):
// Black king on h1: not attacked by rook on e8 (different file and rank)
val board = FenParser.parseBoard("8/4P3/8/8/8/8/8/7k").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R7), sq(File.E, Rank.R8),
PromotionPiece.Rook, Color.White
)
result match
case MoveResult.Moved(newBoard, newHistory, _, _) =>
newBoard.pieceAt(sq(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Rook)))
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Rook))
case _ => fail("Expected Moved with Rook")
test("completePromotion with bishop underpromotion"):
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R7), sq(File.E, Rank.R8),
PromotionPiece.Bishop, Color.White
)
result match
case MoveResult.Moved(newBoard, newHistory, _, _) =>
newBoard.pieceAt(sq(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Bishop)))
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Bishop))
case _ => fail("Expected Moved with Bishop")
test("completePromotion with knight underpromotion"):
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R7), sq(File.E, Rank.R8),
PromotionPiece.Knight, Color.White
)
result match
case MoveResult.Moved(newBoard, newHistory, _, _) =>
newBoard.pieceAt(sq(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Knight)))
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Knight))
case _ => fail("Expected Moved with Knight")
test("completePromotion captures opponent piece"):
// Black king on h1: after white queen captures d8 queen, h1 king is safe (queen on d8 does not attack h1)
val board = FenParser.parseBoard("3q4/4P3/8/8/8/8/8/7k").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R7), sq(File.D, Rank.R8),
PromotionPiece.Queen, Color.White
)
result match
case MoveResult.Moved(newBoard, _, captured, _) =>
newBoard.pieceAt(sq(File.D, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Queen)))
captured should be (Some(Piece(Color.Black, PieceType.Queen)))
case _ => fail("Expected Moved with captured piece")
test("completePromotion for black pawn to R1"):
val board = FenParser.parseBoard("8/8/8/8/4K3/8/4p3/8").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R2), sq(File.E, Rank.R1),
PromotionPiece.Knight, Color.Black
)
result match
case MoveResult.Moved(newBoard, newHistory, _, _) =>
newBoard.pieceAt(sq(File.E, Rank.R1)) should be (Some(Piece(Color.Black, PieceType.Knight)))
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Knight))
case _ => fail("Expected Moved")
test("completePromotion evaluates check after promotion"):
val board = FenParser.parseBoard("3k4/4P3/8/8/8/8/8/8").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.E, Rank.R7), sq(File.E, Rank.R8),
PromotionPiece.Queen, Color.White
)
result should matchPattern { case _: MoveResult.MovedInCheck => }
test("completePromotion full round-trip via processMove then completePromotion"):
// Black king on h1: not attacked by queen on e8
val board = FenParser.parseBoard("8/4P3/8/8/8/8/8/7k").get
GameController.processMove(board, GameHistory.empty, Color.White, "e7e8") match
case MoveResult.PromotionRequired(from, to, boardBefore, histBefore, _, turn) =>
val result = GameController.completePromotion(boardBefore, histBefore, from, to, PromotionPiece.Queen, turn)
result should matchPattern { case _: MoveResult.Moved => }
result match
case MoveResult.Moved(finalBoard, finalHistory, _, _) =>
finalBoard.pieceAt(sq(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Queen)))
finalHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Queen))
case _ => fail("Expected Moved")
case _ => fail("Expected PromotionRequired")
test("completePromotion results in checkmate when promotion delivers checkmate"):
// Black king a8, white pawn h7, white king b6.
// After h7→h8=Q: Qh8 attacks rank 8 putting Ka8 in check;
// a7 covered by Kb6, b7 covered by Kb6, b8 covered by Qh8 — no escape.
val board = FenParser.parseBoard("k7/7P/1K6/8/8/8/8/8").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.H, Rank.R7), sq(File.H, Rank.R8),
PromotionPiece.Queen, Color.White
)
result should matchPattern { case MoveResult.Checkmate(_) => }
result match
case MoveResult.Checkmate(winner) => winner should be (Color.White)
case _ => fail("Expected Checkmate")
test("completePromotion results in stalemate when promotion stalemates opponent"):
// Black king a8, white pawn b7, white bishop c7, white king b6.
// After b7→b8=N: knight on b8 (doesn't check a8); a7 and b7 covered by Kb6;
// b8 defended by Bc7 so Ka8xb8 would walk into bishop — no legal moves.
val board = FenParser.parseBoard("k7/1PB5/1K6/8/8/8/8/8").get
val result = GameController.completePromotion(
board, GameHistory.empty,
sq(File.B, Rank.R7), sq(File.B, Rank.R8),
PromotionPiece.Knight, Color.White
)
result should be (MoveResult.Stalemate)
// ──── half-move clock propagation ────────────────────────────────────
test("processMove: non-pawn non-capture increments halfMoveClock"):
// g1f3 is a knight move — not a pawn, not a capture
processMove(Board.initial, GameHistory.empty, Color.White, "g1f3") match
case MoveResult.Moved(_, newHistory, _, _) =>
newHistory.halfMoveClock shouldBe 1
case other => fail(s"Expected Moved, got $other")
test("processMove: pawn move resets halfMoveClock to 0"):
processMove(Board.initial, GameHistory.empty, Color.White, "e2e4") match
case MoveResult.Moved(_, newHistory, _, _) =>
newHistory.halfMoveClock shouldBe 0
case other => fail(s"Expected Moved, got $other")
test("processMove: capture resets halfMoveClock to 0"):
// White pawn on e5, Black pawn on d6 — exd6 is a capture
val board = Board(Map(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R6) -> Piece.BlackPawn,
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.E, Rank.R8) -> Piece.BlackKing
))
val history = GameHistory(halfMoveClock = 10)
processMove(board, history, Color.White, "e5d6") match
case MoveResult.Moved(_, newHistory, _, _) =>
newHistory.halfMoveClock shouldBe 0
case other => fail(s"Expected Moved, got $other")
test("processMove: clock carries from previous history on non-pawn non-capture"):
val history = GameHistory(halfMoveClock = 5)
processMove(Board.initial, history, Color.White, "g1f3") match
case MoveResult.Moved(_, newHistory, _, _) =>
newHistory.halfMoveClock shouldBe 6
case other => fail(s"Expected Moved, got $other")
@@ -0,0 +1,40 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.{Board, Color}
import de.nowchess.api.game.GameContext
import de.nowchess.chess.observer.*
import de.nowchess.io.fen.FenParser
import de.nowchess.rules.sets.DefaultRules
import scala.collection.mutable
object EngineTestHelpers:
def makeEngine(): GameEngine =
new GameEngine(ruleSet = DefaultRules)
def makeEngineWithBoard(board: Board, turn: Color = Color.White): GameEngine =
GameEngine(initialContext = GameContext.initial.withBoard(board).withTurn(turn))
def loadFen(engine: GameEngine, fen: String): Unit =
engine.loadGame(FenParser, fen)
def captureEvents(engine: GameEngine): mutable.ListBuffer[GameEvent] =
val events = mutable.ListBuffer[GameEvent]()
engine.subscribe(new Observer { def onGameEvent(e: GameEvent): Unit = events += e })
events
class MockObserver extends Observer:
private val _events = mutable.ListBuffer[GameEvent]()
def events: mutable.ListBuffer[GameEvent] = _events
def eventCount: Int = _events.length
def hasEvent[T <: GameEvent](implicit ct: scala.reflect.ClassTag[T]): Boolean =
_events.exists(ct.runtimeClass.isInstance(_))
def getEvent[T <: GameEvent](implicit ct: scala.reflect.ClassTag[T]): Option[T] =
_events.collectFirst { case e if ct.runtimeClass.isInstance(e) => e.asInstanceOf[T] }
override def onGameEvent(event: GameEvent): Unit =
_events += event
def clear(): Unit =
_events.clear()
@@ -1,214 +0,0 @@
package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.observer.{Observer, GameEvent, MoveExecutedEvent, CheckDetectedEvent, BoardResetEvent, InvalidMoveEvent}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
/** Tests for GameEngine edge cases and uncovered paths */
class GameEngineEdgeCasesTest extends AnyFunSuite with Matchers:
test("GameEngine handles empty input"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("Please enter a valid move or command")
test("GameEngine processes quit command"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("quit")
// Quit just returns, no events
observer.events.isEmpty shouldBe true
test("GameEngine processes q command (short form)"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("q")
observer.events.isEmpty shouldBe true
test("GameEngine handles uppercase quit"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("QUIT")
observer.events.isEmpty shouldBe true
test("GameEngine handles undo on empty history"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.canUndo shouldBe false
engine.processUserInput("undo")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("Nothing to undo")
test("GameEngine handles redo on empty redo history"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.canRedo shouldBe false
engine.processUserInput("redo")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("Nothing to redo")
test("GameEngine parses invalid move format"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("invalid_move_format")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("Invalid move format")
test("GameEngine handles lowercase input normalization"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput(" UNDO ") // With spaces and uppercase
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent] // No moves to undo yet
test("GameEngine preserves board state on invalid move"):
val engine = new GameEngine()
val initialBoard = engine.board
engine.processUserInput("invalid")
engine.board shouldBe initialBoard
test("GameEngine preserves turn on invalid move"):
val engine = new GameEngine()
val initialTurn = engine.turn
engine.processUserInput("invalid")
engine.turn shouldBe initialTurn
test("GameEngine undo with no commands available"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// Make a valid move
engine.processUserInput("e2e4")
observer.events.clear()
// Undo it
engine.processUserInput("undo")
// Board should be reset
engine.board shouldBe Board.initial
engine.turn shouldBe Color.White
test("GameEngine redo after undo"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4")
val boardAfterMove = engine.board
val turnAfterMove = engine.turn
observer.events.clear()
engine.processUserInput("undo")
engine.processUserInput("redo")
engine.board shouldBe boardAfterMove
engine.turn shouldBe turnAfterMove
test("GameEngine canUndo flag tracks state correctly"):
val engine = new GameEngine()
engine.canUndo shouldBe false
engine.processUserInput("e2e4")
engine.canUndo shouldBe true
engine.processUserInput("undo")
engine.canUndo shouldBe false
test("GameEngine canRedo flag tracks state correctly"):
val engine = new GameEngine()
engine.canRedo shouldBe false
engine.processUserInput("e2e4")
engine.canRedo shouldBe false
engine.processUserInput("undo")
engine.canRedo shouldBe true
test("GameEngine command history is accessible"):
val engine = new GameEngine()
engine.commandHistory.isEmpty shouldBe true
engine.processUserInput("e2e4")
engine.commandHistory.size shouldBe 1
test("GameEngine processes multiple moves in sequence"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
observer.events.clear()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
observer.events.size shouldBe 2
engine.commandHistory.size shouldBe 2
test("GameEngine can undo multiple moves"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.processUserInput("undo")
engine.turn shouldBe Color.Black
engine.processUserInput("undo")
engine.turn shouldBe Color.White
test("GameEngine thread-safe operations"):
val engine = new GameEngine()
// Access from synchronized methods
val board = engine.board
val history = engine.history
val turn = engine.turn
val canUndo = engine.canUndo
val canRedo = engine.canRedo
board shouldBe Board.initial
canUndo shouldBe false
canRedo shouldBe false
private class MockObserver extends Observer:
val events = mutable.ListBuffer[GameEvent]()
override def onGameEvent(event: GameEvent): Unit =
events += event
@@ -2,7 +2,6 @@ package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.observer.{Observer, GameEvent, CheckDetectedEvent, CheckmateEvent, StalemateEvent}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
@@ -22,12 +21,11 @@ class GameEngineGameEndingTest extends AnyFunSuite with Matchers:
observer.events.clear()
engine.processUserInput("d8h4")
// Verify CheckmateEvent (engine also fires MoveExecutedEvent before CheckmateEvent)
observer.events.last shouldBe a[CheckmateEvent]
// Verify CheckmateEvent
observer.events.size shouldBe 1
observer.events.head shouldBe a[CheckmateEvent]
val event = observer.events.head.asInstanceOf[CheckmateEvent]
val event = observer.events.last.asInstanceOf[CheckmateEvent]
event.winner shouldBe Color.Black
// Board should be reset after checkmate
@@ -50,7 +48,7 @@ class GameEngineGameEndingTest extends AnyFunSuite with Matchers:
val checkEvents = observer.events.collect { case e: CheckDetectedEvent => e }
checkEvents.size shouldBe 1
checkEvents.head.turn shouldBe Color.Black // Black is now in check
checkEvents.head.context.turn shouldBe Color.Black // Black is now in check
// Shortest known stalemate is 19 moves. Here is a faster one:
// e3 a5 Qh5 Ra6 Qxa5 h5 h4 Rah6 Qxc7 f6 Qxd7+ Kf7 Qxb7 Qd3 Qxb8 Qh7 Qxc8 Kg6 Qe6
@@ -1,110 +0,0 @@
package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.observer.{Observer, GameEvent, InvalidMoveEvent}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
/** Tests to maximize handleFailedMove coverage */
class GameEngineHandleFailedMoveTest extends AnyFunSuite with Matchers:
test("GameEngine handles InvalidFormat error type"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("not_a_valid_move_format")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val msg1 = observer.events.head.asInstanceOf[InvalidMoveEvent].reason
msg1 should include("Invalid move format")
test("GameEngine handles NoPiece error type"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("h3h4")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val msg2 = observer.events.head.asInstanceOf[InvalidMoveEvent].reason
msg2 should include("No piece on that square")
test("GameEngine handles WrongColor error type"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4") // White move
observer.events.clear()
engine.processUserInput("a1b2") // Try to move black's rook position with white's move (wrong color)
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val msg3 = observer.events.head.asInstanceOf[InvalidMoveEvent].reason
msg3 should include("That is not your piece")
test("GameEngine handles IllegalMove error type"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e1") // Try pawn backward
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val msg4 = observer.events.head.asInstanceOf[InvalidMoveEvent].reason
msg4 should include("Illegal move")
test("GameEngine invalid move message for InvalidFormat"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("xyz123")
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("coordinate notation")
test("GameEngine invalid move message for NoPiece"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("a3a4") // a3 is empty
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("No piece")
test("GameEngine invalid move message for WrongColor"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4")
observer.events.clear()
engine.processUserInput("e4e5") // e4 has white pawn, it's black's turn
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("not your piece")
test("GameEngine invalid move message for IllegalMove"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e1") // Pawn can't move backward
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("Illegal move")
test("GameEngine board unchanged after each type of invalid move"):
val engine = new GameEngine()
val initial = engine.board
engine.processUserInput("invalid")
engine.board shouldBe initial
engine.processUserInput("h3h4")
engine.board shouldBe initial
engine.processUserInput("e2e1")
engine.board shouldBe initial
@@ -0,0 +1,178 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.{Board, Color, File, PieceType, Rank, Square}
import de.nowchess.api.game.GameContext
import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
import de.nowchess.chess.observer.{GameEvent, InvalidMoveEvent, MoveRedoneEvent, Observer}
import de.nowchess.io.GameContextImport
import de.nowchess.rules.RuleSet
import de.nowchess.rules.sets.DefaultRules
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameEngineIntegrationTest extends AnyFunSuite with Matchers:
private def sq(alg: String): Square =
Square.fromAlgebraic(alg).getOrElse(fail(s"Invalid square in test: $alg"))
private def captureEvents(engine: GameEngine): collection.mutable.ListBuffer[GameEvent] =
val events = collection.mutable.ListBuffer[GameEvent]()
engine.subscribe((event: GameEvent) => events += event)
events
test("accessors expose redo availability and command history"):
val engine = new GameEngine()
engine.canRedo shouldBe false
engine.commandHistory shouldBe empty
engine.processUserInput("e2e4")
engine.commandHistory.nonEmpty shouldBe true
test("processUserInput handles undo redo empty and malformed commands"):
val engine = new GameEngine()
val events = captureEvents(engine)
engine.processUserInput("")
engine.processUserInput("oops")
engine.processUserInput("undo")
engine.processUserInput("redo")
events.count(_.isInstanceOf[InvalidMoveEvent]) should be >= 3
test("processUserInput emits Illegal move for syntactically valid but illegal target"):
val engine = new GameEngine()
val events = captureEvents(engine)
engine.processUserInput("e2e5")
events.exists {
case InvalidMoveEvent(_, reason) => reason.contains("Illegal move")
case _ => false
} shouldBe true
test("loadGame returns Left when importer fails"):
val engine = new GameEngine()
val failingImporter = new GameContextImport:
def importGameContext(input: String): Either[String, GameContext] = Left("boom")
engine.loadGame(failingImporter, "ignored") shouldBe Left("boom")
test("loadPosition replaces context clears history and notifies reset"):
val engine = new GameEngine()
val events = captureEvents(engine)
engine.processUserInput("e2e4")
val target = GameContext.initial.withTurn(Color.Black)
engine.loadPosition(target)
engine.context shouldBe target
engine.commandHistory shouldBe empty
events.lastOption.exists(_.isInstanceOf[de.nowchess.chess.observer.BoardResetEvent]) shouldBe true
test("redo event includes captured piece description when replaying a capture"):
val engine = new GameEngine()
val events = captureEvents(engine)
EngineTestHelpers.loadFen(engine, "4k3/8/8/8/8/8/4K3/R6r w - - 0 1")
events.clear()
engine.processUserInput("a1h1")
engine.processUserInput("undo")
engine.processUserInput("redo")
val redo = events.collectFirst { case e: MoveRedoneEvent => e }
redo.flatMap(_.capturedPiece) shouldBe Some("Black Rook")
test("loadGame replay handles promotion moves when pending promotion exists"):
val promotionMove = Move(sq("e2"), sq("e8"), MoveType.Promotion(PromotionPiece.Queen))
val permissiveRules = new RuleSet:
def candidateMoves(context: GameContext, square: Square): List[Move] = legalMoves(context, square)
def legalMoves(context: GameContext, square: Square): List[Move] =
if square == sq("e2") then List(promotionMove) else List.empty
def allLegalMoves(context: GameContext): List[Move] = List(promotionMove)
def isCheck(context: GameContext): Boolean = false
def isCheckmate(context: GameContext): Boolean = false
def isStalemate(context: GameContext): Boolean = false
def isInsufficientMaterial(context: GameContext): Boolean = false
def isFiftyMoveRule(context: GameContext): Boolean = false
def applyMove(context: GameContext, move: Move): GameContext = DefaultRules.applyMove(context, move)
val engine = new GameEngine(ruleSet = permissiveRules)
val importer = new GameContextImport:
def importGameContext(input: String): Either[String, GameContext] =
Right(GameContext.initial.copy(moves = List(promotionMove)))
engine.loadGame(importer, "ignored") shouldBe Right(())
engine.context.moves.lastOption shouldBe Some(promotionMove)
test("loadGame replay restores previous context when promotion cannot be completed"):
val promotionMove = Move(sq("e2"), sq("e8"), MoveType.Promotion(PromotionPiece.Queen))
val noLegalMoves = new RuleSet:
def candidateMoves(context: GameContext, square: Square): List[Move] = List.empty
def legalMoves(context: GameContext, square: Square): List[Move] = List.empty
def allLegalMoves(context: GameContext): List[Move] = List.empty
def isCheck(context: GameContext): Boolean = false
def isCheckmate(context: GameContext): Boolean = false
def isStalemate(context: GameContext): Boolean = false
def isInsufficientMaterial(context: GameContext): Boolean = false
def isFiftyMoveRule(context: GameContext): Boolean = false
def applyMove(context: GameContext, move: Move): GameContext = context
val engine = new GameEngine(ruleSet = noLegalMoves)
engine.processUserInput("e2e4")
val saved = engine.context
val importer = new GameContextImport:
def importGameContext(input: String): Either[String, GameContext] =
Right(GameContext.initial.copy(moves = List(promotionMove)))
val result = engine.loadGame(importer, "ignored")
result.isLeft shouldBe true
result.left.toOption.get should include("Promotion required")
engine.context shouldBe saved
test("loadGame replay executes non-promotion moves through default replay branch"):
val normalMove = Move(sq("e2"), sq("e4"), MoveType.Normal())
val engine = new GameEngine()
engine.replayMoves(List(normalMove), engine.context) shouldBe Right(())
engine.context.moves.lastOption shouldBe Some(normalMove)
test("replayMoves skips later moves after the first move triggers an error"):
val engine = new GameEngine()
val saved = engine.context
val illegalPromotion = Move(sq("e2"), sq("e1"), MoveType.Promotion(PromotionPiece.Queen))
val trailingMove = Move(sq("e2"), sq("e4"))
engine.replayMoves(List(illegalPromotion, trailingMove), saved) shouldBe Left("Promotion required for move e2e1")
engine.context shouldBe saved
test("normalMoveNotation handles missing source piece"):
val engine = new GameEngine()
val result = engine.normalMoveNotation(Move(sq("e3"), sq("e4")), Board.initial, isCapture = false)
result shouldBe "e4"
test("pieceNotation default branch returns empty string"):
val engine = new GameEngine()
val result = engine.pieceNotation(PieceType.Pawn)
result shouldBe ""
test("observerCount reflects subscribe and unsubscribe operations"):
val engine = new GameEngine()
val observer = new Observer:
def onGameEvent(event: GameEvent): Unit = ()
engine.observerCount shouldBe 0
engine.subscribe(observer)
engine.observerCount shouldBe 1
engine.unsubscribe(observer)
engine.observerCount shouldBe 0
@@ -1,114 +0,0 @@
package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.observer.{Observer, GameEvent, InvalidMoveEvent, MoveExecutedEvent}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
/** Tests for GameEngine invalid move handling via handleFailedMove */
class GameEngineInvalidMovesTest extends AnyFunSuite with Matchers:
test("GameEngine handles no piece at source square"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// Try to move from h1 which may be empty or not have our piece
// We'll try from a clearly empty square
engine.processUserInput("h1h2")
// Should get an InvalidMoveEvent about NoPiece
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
test("GameEngine handles moving wrong color piece"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// White moves first
engine.processUserInput("e2e4")
observer.events.clear()
// White tries to move again (should fail - it's black's turn)
// But we need to try a move that looks legal but has wrong color
// This is hard to test because we'd need to be black and move white's piece
// Let's skip this for now and focus on testable cases
// Actually, let's try moving a square that definitely has the wrong piece
// Move a white pawn as black by reaching that position
engine.processUserInput("e7e5")
observer.events.clear()
// Now try to move white's e4 pawn as black (it's black's turn but e4 is white)
engine.processUserInput("e4e5")
observer.events.size shouldBe 1
val event = observer.events.head
event shouldBe an[InvalidMoveEvent]
test("GameEngine handles illegal move"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// A pawn can't move backward
engine.processUserInput("e2e1")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("Illegal move")
test("GameEngine handles pawn trying to move 3 squares"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// Pawn can only move 1 or 2 squares on first move, not 3
engine.processUserInput("e2e5")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
test("GameEngine handles moving from empty square"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// h3 is empty in starting position
engine.processUserInput("h3h4")
observer.events.size shouldBe 1
observer.events.head shouldBe an[InvalidMoveEvent]
val event = observer.events.head.asInstanceOf[InvalidMoveEvent]
event.reason should include("No piece on that square")
test("GameEngine processes valid move after invalid attempt"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
// Try invalid move
engine.processUserInput("h3h4")
observer.events.clear()
// Make valid move
engine.processUserInput("e2e4")
observer.events.size shouldBe 1
observer.events.head shouldBe an[MoveExecutedEvent]
test("GameEngine maintains state after failed move attempt"):
val engine = new GameEngine()
val initialTurn = engine.turn
val initialBoard = engine.board
// Try invalid move
engine.processUserInput("h3h4")
// State should not change
engine.turn shouldBe initialTurn
engine.board shouldBe initialBoard
@@ -0,0 +1,43 @@
package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.api.game.GameContext
import de.nowchess.chess.observer.{Observer, GameEvent, PgnLoadedEvent}
import de.nowchess.io.pgn.PgnParser
import de.nowchess.io.fen.FenParser
import de.nowchess.io.pgn.PgnExporter
import de.nowchess.io.fen.FenExporter
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameEngineLoadGameTest extends AnyFunSuite with Matchers:
test("loadGame with PgnParser: loads valid PGN and enables undo/redo"):
val engine = new GameEngine()
val pgn = "[Event \"Test\"]\n\n1. e4 e5\n"
val result = engine.loadGame(PgnParser, pgn)
result shouldBe Right(())
engine.context.moves.size shouldBe 2
engine.canUndo shouldBe true
test("loadGame with FenParser: loads position without replaying moves"):
val engine = new GameEngine()
val fen = "8/4P3/4k3/8/8/8/8/8 w - - 0 1"
val result = engine.loadGame(FenParser, fen)
result shouldBe Right(())
engine.context.moves.isEmpty shouldBe true
engine.canUndo shouldBe false
test("exportGame with PgnExporter: exports current game as PGN"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
val pgn = engine.exportGame(PgnExporter)
pgn.contains("e4") shouldBe true
pgn.contains("e5") shouldBe true
private class MockObserver extends Observer:
val events = mutable.ListBuffer[GameEvent]()
override def onGameEvent(event: GameEvent): Unit =
events += event
@@ -1,165 +0,0 @@
package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.observer.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameEngineLoadPgnTest extends AnyFunSuite with Matchers:
private class EventCapture extends Observer:
val events: mutable.Buffer[GameEvent] = mutable.Buffer.empty
def onGameEvent(event: GameEvent): Unit = events += event
def lastEvent: GameEvent = events.last
// ── loadPgn happy path ────────────────────────────────────────────────────
test("loadPgn: valid PGN returns Right and updates board/history"):
val engine = new GameEngine()
val pgn =
"""[Event "Test"]
1. e4 e5
"""
val result = engine.loadPgn(pgn)
result shouldBe Right(())
engine.history.moves.length shouldBe 2
engine.turn shouldBe Color.White
test("loadPgn: emits PgnLoadedEvent on success"):
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
val pgn = "[Event \"T\"]\n\n1. e4 e5\n"
engine.loadPgn(pgn)
cap.events.last shouldBe a[PgnLoadedEvent]
test("loadPgn: after load canUndo is true and canRedo is false"):
val engine = new GameEngine()
val pgn = "[Event \"T\"]\n\n1. e4 e5\n"
engine.loadPgn(pgn) shouldBe Right(())
engine.canUndo shouldBe true
engine.canRedo shouldBe false
test("loadPgn: undo works after loading PGN"):
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
val pgn = "[Event \"T\"]\n\n1. e4 e5\n"
engine.loadPgn(pgn)
cap.events.clear()
engine.undo()
cap.events.last shouldBe a[MoveUndoneEvent]
engine.history.moves.length shouldBe 1
test("loadPgn: undo then redo restores position after PGN load"):
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
val pgn = "[Event \"T\"]\n\n1. e4 e5\n"
engine.loadPgn(pgn)
val boardAfterLoad = engine.board
engine.undo()
engine.redo()
cap.events.last shouldBe a[MoveRedoneEvent]
engine.board shouldBe boardAfterLoad
engine.history.moves.length shouldBe 2
test("loadPgn: longer game loads all moves into command history"):
val engine = new GameEngine()
val pgn =
"""[Event "Ruy Lopez"]
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6
"""
engine.loadPgn(pgn) shouldBe Right(())
engine.history.moves.length shouldBe 6
engine.commandHistory.length shouldBe 6
test("loadPgn: invalid PGN returns Left and does not change state"):
val engine = new GameEngine()
val initial = engine.board
val result = engine.loadPgn("[Event \"T\"]\n\n1. Qd4\n")
result.isLeft shouldBe true
// state is reset to initial (reset happens before replay, which fails)
engine.history.moves shouldBe empty
// ── undo/redo notation events ─────────────────────────────────────────────
test("undo emits MoveUndoneEvent with pgnNotation"):
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
engine.processUserInput("e2e4")
cap.events.clear()
engine.undo()
cap.events.last shouldBe a[MoveUndoneEvent]
val evt = cap.events.last.asInstanceOf[MoveUndoneEvent]
evt.pgnNotation should not be empty
evt.pgnNotation shouldBe "e4" // pawn to e4
test("redo emits MoveRedoneEvent with pgnNotation"):
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
engine.processUserInput("e2e4")
engine.undo()
cap.events.clear()
engine.redo()
cap.events.last shouldBe a[MoveRedoneEvent]
val evt = cap.events.last.asInstanceOf[MoveRedoneEvent]
evt.pgnNotation should not be empty
evt.pgnNotation shouldBe "e4"
test("undo emits MoveUndoneEvent with empty notation when history is empty (after checkmate reset)"):
// Simulate state where canUndo=true but currentHistory is empty (board reset on checkmate).
// We achieve this by examining the branch: provide a MoveCommand with empty history saved.
// The simplest proxy: undo a move that reset history (stalemate/checkmate). We'll
// use a contrived engine state by direct command manipulation — instead, just verify
// that after a normal move-and-undo the notation is present; the empty-history branch
// is exercised internally when gameEnd resets state. We cover it via a castling undo.
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
// Play moves that let white castle kingside: e4 e5 Nf3 Nc6 Bc4 Bc5 O-O
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.processUserInput("g1f3")
engine.processUserInput("b8c6")
engine.processUserInput("f1c4")
engine.processUserInput("f8c5")
engine.processUserInput("e1g1") // white castles kingside
cap.events.clear()
engine.undo()
val evt = cap.events.last.asInstanceOf[MoveUndoneEvent]
evt.pgnNotation shouldBe "O-O"
test("redo emits MoveRedoneEvent with from/to squares and capturedPiece"):
val engine = new GameEngine()
val cap = new EventCapture()
engine.subscribe(cap)
// White builds a capture on the a-file: b4, ... a6, b5, ... h6, bxa6
engine.processUserInput("b2b4")
engine.processUserInput("a7a6")
engine.processUserInput("b4b5")
engine.processUserInput("h7h6")
engine.processUserInput("b5a6") // white pawn captures black pawn
engine.undo()
cap.events.clear()
engine.redo()
val evt = cap.events.last.asInstanceOf[MoveRedoneEvent]
evt.fromSquare shouldBe "b5"
evt.toSquare shouldBe "a6"
evt.capturedPiece.isDefined shouldBe true
test("loadPgn: clears previous game state before loading"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val pgn = "[Event \"T\"]\n\n1. d4 d5\n"
engine.loadPgn(pgn) shouldBe Right(())
// First move should be d4, not e4
engine.history.moves.head.to shouldBe de.nowchess.api.board.Square(
de.nowchess.api.board.File.D, de.nowchess.api.board.Rank.R4
)
@@ -0,0 +1,127 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.{Board, Color, File, Rank, Square}
import de.nowchess.api.game.GameContext
import de.nowchess.api.move.PromotionPiece
import de.nowchess.io.fen.FenParser
import de.nowchess.chess.observer.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
/** Tests that exercise moveToPgn branches not covered by other test files:
* - CastleQueenside (line 223)
* - EnPassant notation (lines 224-225) and computeCaptured EnPassant (lines 254-255)
* - Promotion(Bishop) notation (line 230)
* - King normal move notation (line 246)
*/
class GameEngineNotationTest extends AnyFunSuite with Matchers:
private def captureEvents(engine: GameEngine): collection.mutable.ListBuffer[GameEvent] =
val buf = collection.mutable.ListBuffer[GameEvent]()
engine.subscribe(new Observer { def onGameEvent(e: GameEvent): Unit = buf += e })
buf
// ── Queenside castling (line 223) ──────────────────────────────────
test("undo after queenside castling emits MoveUndoneEvent with O-O-O notation"):
// FEN: White king on e1, queenside rook on a1, b1/c1/d1 clear, black king away
val board = FenParser.parseBoard("k7/8/8/8/8/8/8/R3K3").get
// Castling rights: white queen-side only (no king-side rook present)
val castlingRights = de.nowchess.api.board.CastlingRights(
whiteKingSide = false,
whiteQueenSide = true,
blackKingSide = false,
blackQueenSide = false
)
val ctx = GameContext.initial
.withBoard(board)
.withTurn(Color.White)
.withCastlingRights(castlingRights)
val engine = new GameEngine(ctx)
val events = captureEvents(engine)
// White castles queenside: e1c1
engine.processUserInput("e1c1")
events.exists(_.isInstanceOf[MoveExecutedEvent]) should be (true)
events.clear()
engine.undo()
val evt = events.collect { case e: MoveUndoneEvent => e }.head
evt.pgnNotation shouldBe "O-O-O"
// ── En passant notation + computeCaptured (lines 224-225, 254-255) ─
test("undo after en passant emits MoveUndoneEvent with file-x-destination notation"):
// White pawn on e5, black pawn on d5 (just double-pushed), en passant square d6
val board = FenParser.parseBoard("k7/8/8/3pP3/8/8/8/7K").get
val epSquare = Square.fromAlgebraic("d6")
val ctx = GameContext.initial
.withBoard(board)
.withTurn(Color.White)
.withEnPassantSquare(epSquare)
.withCastlingRights(de.nowchess.api.board.CastlingRights(false, false, false, false))
val engine = new GameEngine(ctx)
val events = captureEvents(engine)
// White pawn on e5 captures en passant to d6
engine.processUserInput("e5d6")
events.exists(_.isInstanceOf[MoveExecutedEvent]) should be (true)
// Verify the captured pawn was found (computeCaptured EnPassant branch)
val moveEvt = events.collect { case e: MoveExecutedEvent => e }.head
moveEvt.capturedPiece shouldBe defined
moveEvt.capturedPiece.get should include ("Black")
events.clear()
engine.undo()
val undoEvt = events.collect { case e: MoveUndoneEvent => e }.head
undoEvt.pgnNotation shouldBe "exd6"
// ── Bishop underpromotion notation (line 230) ──────────────────────
test("undo after bishop underpromotion emits MoveUndoneEvent with =B notation"):
val board = FenParser.parseBoard("8/4P3/8/8/8/8/k7/7K").get
val ctx = GameContext.initial
.withBoard(board)
.withTurn(Color.White)
.withCastlingRights(de.nowchess.api.board.CastlingRights(false, false, false, false))
val engine = new GameEngine(ctx)
val events = captureEvents(engine)
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Bishop)
events.clear()
engine.undo()
val evt = events.collect { case e: MoveUndoneEvent => e }.head
evt.pgnNotation shouldBe "e8=B"
// ── King normal move notation (line 246) ───────────────────────────
test("undo after king move emits MoveUndoneEvent with K notation"):
// White king on e1, no castling rights, black king far away
val board = FenParser.parseBoard("k7/8/8/8/8/8/8/4K3").get
val ctx = GameContext.initial
.withBoard(board)
.withTurn(Color.White)
.withCastlingRights(de.nowchess.api.board.CastlingRights(false, false, false, false))
val engine = new GameEngine(ctx)
val events = captureEvents(engine)
// King moves e1 -> f1
engine.processUserInput("e1f1")
events.exists(_.isInstanceOf[MoveExecutedEvent]) should be (true)
events.clear()
engine.undo()
val evt = events.collect { case e: MoveUndoneEvent => e }.head
evt.pgnNotation should startWith ("K")
evt.pgnNotation should include ("f1")
@@ -0,0 +1,176 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.Color
import de.nowchess.chess.observer.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameEngineOutcomesTest extends AnyFunSuite with Matchers:
// ── Checkmate ───────────────────────────────────────────────────
test("checkmate ends game with CheckmateEvent"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.processUserInput("f2f3")
engine.processUserInput("e7e5")
engine.processUserInput("g2g4")
observer.clear()
engine.processUserInput("d8h4")
observer.hasEvent[CheckmateEvent] shouldBe true
test("checkmate with white winner"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.processUserInput("f1c4")
engine.processUserInput("b8c6")
engine.processUserInput("d1h5")
engine.processUserInput("g8f6")
observer.clear()
engine.processUserInput("h5f7")
val evt = observer.getEvent[CheckmateEvent]
evt.isDefined shouldBe true
evt.get.winner shouldBe Color.White
// ── Stalemate ───────────────────────────────────────────────────
test("stalemate ends game with StalemateEvent"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
val moves = List(
"e2e3", "a7a5",
"d1h5", "a8a6",
"h5a5", "h7h5",
"h2h4", "a6h6",
"a5c7", "f7f6",
"c7d7", "e8f7",
"d7b7", "d8d3",
"b7b8", "d3h7",
"b8c8", "f7g6"
)
moves.foreach(engine.processUserInput)
observer.clear()
engine.processUserInput("c8e6")
observer.hasEvent[StalemateEvent] shouldBe true
test("stalemate when king has no moves and no pieces"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
val moves = List(
"e2e3", "a7a5",
"d1h5", "a8a6",
"h5a5", "h7h5",
"h2h4", "a6h6",
"a5c7", "f7f6",
"c7d7", "e8f7",
"d7b7", "d8d3",
"b7b8", "d3h7",
"b8c8", "f7g6",
"c8e6"
)
moves.foreach(engine.processUserInput)
observer.hasEvent[StalemateEvent] shouldBe true
engine.turn shouldBe Color.White
// ── Check detection ────────────────────────────────────────────
test("check detected after move puts king in check"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.processUserInput("f1c4")
engine.processUserInput("g8f6")
observer.clear()
engine.processUserInput("c4f7")
observer.hasEvent[CheckDetectedEvent] shouldBe true
test("check by knight"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "8/4k3/8/8/3N4/8/8/4K3 w - - 0 1")
observer.clear()
engine.processUserInput("d4f5")
observer.hasEvent[CheckDetectedEvent] shouldBe true
// ── Fifty-move rule ────────────────────────────────────────────
test("fifty-move rule triggers when half-move clock reaches 100"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 99 1")
observer.clear()
engine.processUserInput("g1f3")
observer.hasEvent[FiftyMoveRuleAvailableEvent] shouldBe true
test("fifty-move rule clock resets on pawn move"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 50 1")
engine.processUserInput("a2a3")
// Clock should reset to 0 after pawn move
engine.context.halfMoveClock shouldBe 0
test("fifty-move rule clock resets on capture"):
val engine = EngineTestHelpers.makeEngine()
// FEN: white pawn on e5, black pawn on d6, clock at 50
EngineTestHelpers.loadFen(engine, "4k3/8/3p4/4P3/8/8/8/4K3 w - - 50 1")
engine.processUserInput("e5d6")
// Clock should reset to 0 after capture
engine.context.halfMoveClock shouldBe 0
// ── Draw claim ────────────────────────────────────────────────
test("draw can be claimed when fifty-move rule is available"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 100 1")
observer.clear()
engine.processUserInput("draw")
observer.hasEvent[DrawClaimedEvent] shouldBe true
test("draw cannot be claimed when not available"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.processUserInput("draw")
observer.hasEvent[InvalidMoveEvent] shouldBe true
@@ -1,10 +1,12 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.{Board, Color, File, Piece, PieceType, Rank, Square}
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.notation.FenParser
import de.nowchess.api.game.GameContext
import de.nowchess.api.move.{Move, MoveType, PromotionPiece}
import de.nowchess.io.fen.FenParser
import de.nowchess.chess.observer.*
import de.nowchess.rules.RuleSet
import de.nowchess.rules.sets.DefaultRules
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
@@ -17,9 +19,12 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
engine.subscribe(new Observer { def onGameEvent(e: GameEvent): Unit = events += e })
events
private def engineWith(board: Board, turn: Color = Color.White): GameEngine =
new GameEngine(initialContext = GameContext.initial.withBoard(board).withTurn(turn))
test("processUserInput fires PromotionRequiredEvent when pawn reaches back rank") {
val promotionBoard = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = promotionBoard)
val engine = engineWith(promotionBoard)
val events = captureEvents(engine)
engine.processUserInput("e7e8")
@@ -30,7 +35,7 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
test("isPendingPromotion is true after PromotionRequired input") {
val promotionBoard = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = promotionBoard)
val engine = engineWith(promotionBoard)
captureEvents(engine)
engine.processUserInput("e7e8")
@@ -45,7 +50,7 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
test("completePromotion fires MoveExecutedEvent with promoted piece") {
val promotionBoard = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = promotionBoard)
val engine = engineWith(promotionBoard)
val events = captureEvents(engine)
engine.processUserInput("e7e8")
@@ -54,13 +59,13 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
engine.isPendingPromotion should be (false)
engine.board.pieceAt(sq(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Queen)))
engine.board.pieceAt(sq(File.E, Rank.R7)) should be (None)
engine.history.moves.head.promotionPiece should be (Some(PromotionPiece.Queen))
engine.context.moves.last.moveType shouldBe MoveType.Promotion(PromotionPiece.Queen)
events.exists(_.isInstanceOf[MoveExecutedEvent]) should be (true)
}
test("completePromotion with rook underpromotion") {
val promotionBoard = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = promotionBoard)
val engine = engineWith(promotionBoard)
captureEvents(engine)
engine.processUserInput("e7e8")
@@ -81,7 +86,7 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
test("completePromotion fires CheckDetectedEvent when promotion gives check") {
val promotionBoard = FenParser.parseBoard("3k4/4P3/8/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = promotionBoard)
val engine = engineWith(promotionBoard)
val events = captureEvents(engine)
engine.processUserInput("e7e8")
@@ -91,9 +96,8 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
}
test("completePromotion results in Moved when promotion doesn't give check") {
// White pawn on e7, black king on a2 (far away, not in check after promotion)
val board = FenParser.parseBoard("8/4P3/8/8/8/8/k7/8").get
val engine = new GameEngine(initialBoard = board)
val engine = engineWith(board)
val events = captureEvents(engine)
engine.processUserInput("e7e8")
@@ -106,10 +110,8 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
}
test("completePromotion results in Checkmate when promotion delivers checkmate") {
// Black king on a8, white king on b6, white pawn on h7
// h7->h8=Q delivers checkmate
val board = FenParser.parseBoard("k7/7P/1K6/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = board)
val engine = engineWith(board)
val events = captureEvents(engine)
engine.processUserInput("h7h8")
@@ -120,10 +122,8 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
}
test("completePromotion results in Stalemate when promotion creates stalemate") {
// Black king on a8, white pawn on b7, white bishop on c7, white king on b6
// b7->b8=N: no check; Ka8 has no legal moves -> stalemate
val board = FenParser.parseBoard("k7/1PB5/1K6/8/8/8/8/8").get
val engine = new GameEngine(initialBoard = board)
val engine = engineWith(board)
val events = captureEvents(engine)
engine.processUserInput("b7b8")
@@ -134,10 +134,8 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
}
test("completePromotion with black pawn promotion results in Moved") {
// Black pawn e2, white king h3 (not on rank 1 or file e), black king a8
// e2->e1=Q: queen on e1 does not attack h3 -> normal Moved
val board = FenParser.parseBoard("k7/8/8/8/8/7K/4p3/8").get
val engine = new GameEngine(initialBoard = board, initialTurn = Color.Black)
val engine = engineWith(board, Color.Black)
val events = captureEvents(engine)
engine.processUserInput("e2e1")
@@ -149,19 +147,51 @@ class GameEnginePromotionTest extends AnyFunSuite with Matchers:
events.exists(_.isInstanceOf[CheckDetectedEvent]) should be (false)
}
test("completePromotion catch-all fires InvalidMoveEvent for unexpected MoveResult") {
// Inject a function that returns an unexpected MoveResult to hit the catch-all case
test("completePromotion fires InvalidMoveEvent when legalMoves returns only Normal moves to back rank") {
// Custom RuleSet: delegates all methods to StandardRules except legalMoves,
// which strips Promotion move types and returns Normal moves instead.
// This makes completePromotion unable to find Move(from, to, Promotion(Queen)),
// triggering the "Error completing promotion." branch.
val delegatingRuleSet: RuleSet = new RuleSet:
def candidateMoves(context: GameContext, square: Square): List[Move] =
DefaultRules.candidateMoves(context, square)
def legalMoves(context: GameContext, square: Square): List[Move] =
DefaultRules.legalMoves(context, square).map { m =>
m.moveType match
case MoveType.Promotion(_) => Move(m.from, m.to, MoveType.Normal())
case _ => m
}
def allLegalMoves(context: GameContext): List[Move] =
DefaultRules.allLegalMoves(context)
def isCheck(context: GameContext): Boolean =
DefaultRules.isCheck(context)
def isCheckmate(context: GameContext): Boolean =
DefaultRules.isCheckmate(context)
def isStalemate(context: GameContext): Boolean =
DefaultRules.isStalemate(context)
def isInsufficientMaterial(context: GameContext): Boolean =
DefaultRules.isInsufficientMaterial(context)
def isFiftyMoveRule(context: GameContext): Boolean =
DefaultRules.isFiftyMoveRule(context)
def applyMove(context: GameContext, move: Move): GameContext =
DefaultRules.applyMove(context, move)
val promotionBoard = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val stubFn: (de.nowchess.api.board.Board, de.nowchess.chess.logic.GameHistory, Square, Square, PromotionPiece, Color) => de.nowchess.chess.controller.MoveResult =
(_, _, _, _, _, _) => de.nowchess.chess.controller.MoveResult.NoPiece
val engine = new GameEngine(initialBoard = promotionBoard, completePromotionFn = stubFn)
val initialCtx = GameContext.initial.withBoard(promotionBoard).withTurn(Color.White)
val engine = new GameEngine(initialCtx, delegatingRuleSet)
val events = captureEvents(engine)
// isPromotionMove will fire because pawn is on rank 7 heading to rank 8,
// and legalMoves returns Normal candidates (still non-empty) — sets pendingPromotion
engine.processUserInput("e7e8")
engine.isPendingPromotion should be (true)
// completePromotion looks for Move(e7, e8, Promotion(Queen)) in legalMoves,
// but only Normal moves exist → fires InvalidMoveEvent
engine.completePromotion(PromotionPiece.Queen)
engine.isPendingPromotion should be (false)
events.exists(_.isInstanceOf[InvalidMoveEvent]) should be (true)
val invalidEvt = events.collect { case e: InvalidMoveEvent => e }.last
invalidEvt.reason should include ("Error completing promotion")
}
@@ -0,0 +1,132 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.{Color, File, Rank, Square, Piece}
import de.nowchess.api.game.GameContext
import de.nowchess.chess.observer.*
import de.nowchess.io.fen.FenParser
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
import scala.collection.mutable
class GameEngineScenarioTest extends AnyFunSuite with Matchers:
// ── Observer wiring ────────────────────────────────────────────
test("observer subscribe and unsubscribe behavior"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4")
observer.hasEvent[MoveExecutedEvent] shouldBe true
val countBeforeUnsubscribe = observer.eventCount
engine.subscribe(observer)
engine.unsubscribe(observer)
engine.processUserInput("e2e4")
observer.eventCount shouldBe countBeforeUnsubscribe
// ── Initial state ──────────────────────────────────────────────
test("initial engine state is standard"):
val engine = EngineTestHelpers.makeEngine()
engine.board.pieceAt(Square(File.E, Rank.R1)) shouldBe Some(Piece.WhiteKing)
engine.turn shouldBe Color.White
// ── Quit command ──────────────────────────────────────────────
test("quit aliases and reset keep engine responsive"):
val engine = EngineTestHelpers.makeEngine()
engine.processUserInput("quit")
engine.processUserInput("q")
engine.processUserInput("e2e4")
engine.reset()
engine.board.pieceAt(Square(File.E, Rank.R2)) shouldBe Some(Piece.WhitePawn)
engine.turn shouldBe Color.White
// ── Turn toggling ──────────────────────────────────────────────
test("turn toggles across valid move sequence"):
val engine = EngineTestHelpers.makeEngine()
engine.processUserInput("e2e4")
engine.turn shouldBe Color.Black
engine.processUserInput("e7e5")
engine.turn shouldBe Color.White
// ── Invalid moves (minimal) ────────────────────────────────────
test("invalid move forms trigger InvalidMoveEvent and keep turn where relevant"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.processUserInput("h3h4")
observer.hasEvent[InvalidMoveEvent] shouldBe true
engine.turn shouldBe Color.White // turn unchanged
engine.processUserInput("e7e5") // try to move black pawn on white's turn
observer.hasEvent[InvalidMoveEvent] shouldBe true
engine.processUserInput("e2e4")
engine.processUserInput("e5e4") // pawn backward
observer.hasEvent[InvalidMoveEvent] shouldBe true
// ── Undo/Redo ────────────────────────────────────────────────
test("undo redo success and empty-history failures"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
engine.undo()
observer.hasEvent[InvalidMoveEvent] shouldBe true
observer.clear()
engine.processUserInput("e2e4")
engine.undo()
engine.board.pieceAt(Square(File.E, Rank.R2)) shouldBe Some(Piece.WhitePawn)
engine.turn shouldBe Color.White
engine.redo()
engine.board.pieceAt(Square(File.E, Rank.R4)) shouldBe Some(Piece.WhitePawn)
engine.turn shouldBe Color.Black
observer.clear()
engine.redo()
observer.hasEvent[InvalidMoveEvent] shouldBe true
// ── Fifty-move rule ────────────────────────────────────────────
test("fifty-move event and draw claim success/failure"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
// Load FEN with half-move clock at 99
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 99 1")
observer.clear()
// Use a legal non-pawn non-capture move so the clock increments to 100.
engine.processUserInput("g1f3")
observer.hasEvent[FiftyMoveRuleAvailableEvent] shouldBe true
// Load position with sufficient move history for draw claim
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 100 1")
observer.clear()
engine.processUserInput("draw")
observer.hasEvent[DrawClaimedEvent] shouldBe true
// Initial position has no draw available
observer.clear()
engine.reset()
engine.processUserInput("draw")
observer.hasEvent[InvalidMoveEvent] shouldBe true
@@ -0,0 +1,209 @@
package de.nowchess.chess.engine
import de.nowchess.api.board.Color
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.observer.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameEngineSpecialMovesTest extends AnyFunSuite with Matchers:
// ── Castling ────────────────────────────────────────────────────
test("kingside castling executes successfully"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
// FEN: white king on e1, rook on h1, f1/g1 clear
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQK2R w KQkq - 0 1")
observer.clear()
engine.processUserInput("e1g1")
observer.hasEvent[MoveExecutedEvent] shouldBe true
engine.turn shouldBe Color.Black
test("queenside castling executes successfully"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
// FEN: white king on e1, rook on a1, b1/c1/d1 clear
EngineTestHelpers.loadFen(engine, "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/R3K2R w KQkq - 0 1")
observer.clear()
engine.processUserInput("e1c1")
observer.hasEvent[MoveExecutedEvent] shouldBe true
engine.turn shouldBe Color.Black
test("undo castling emits PGN notation"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "k7/8/8/8/8/8/8/R3K3 w Q - 0 1")
observer.clear()
engine.processUserInput("e1c1")
observer.clear()
engine.undo()
val evt = observer.getEvent[MoveUndoneEvent]
evt.isDefined shouldBe true
evt.get.pgnNotation shouldBe "O-O-O"
// ── En passant ──────────────────────────────────────────────────
test("en passant capture executes successfully"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
// FEN: white pawn e5, black pawn d5 (just pushed), en passant square d6
EngineTestHelpers.loadFen(engine, "k7/8/8/3pP3/8/8/8/7K w - d6 0 1")
observer.clear()
engine.processUserInput("e5d6")
observer.hasEvent[MoveExecutedEvent] shouldBe true
val moveEvt = observer.getEvent[MoveExecutedEvent]
moveEvt.get.capturedPiece shouldBe defined // pawn was captured
test("undo en passant emits file-x-destination notation"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "k7/8/8/3pP3/8/8/8/7K w - d6 0 1")
observer.clear()
engine.processUserInput("e5d6")
observer.clear()
engine.undo()
val evt = observer.getEvent[MoveUndoneEvent]
evt.isDefined shouldBe true
evt.get.pgnNotation shouldBe "exd6"
// ── Pawn promotion ─────────────────────────────────────────────
test("pawn reaching back rank requires promotion"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "8/4P3/4k3/8/8/8/8/8 w - - 0 1")
observer.clear()
engine.processUserInput("e7e8")
observer.hasEvent[PromotionRequiredEvent] shouldBe true
engine.isPendingPromotion shouldBe true
test("completePromotion to Queen executes move"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "8/4P3/8/8/8/8/k7/8 w - - 0 1")
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Queen)
engine.isPendingPromotion shouldBe false
engine.turn shouldBe Color.Black
test("completePromotion to Rook executes move"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "8/4P3/8/8/8/8/k7/8 w - - 0 1")
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Rook)
engine.isPendingPromotion shouldBe false
engine.turn shouldBe Color.Black
test("completePromotion to Bishop executes move"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "8/4P3/8/8/8/8/k7/8 w - - 0 1")
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Bishop)
engine.isPendingPromotion shouldBe false
engine.turn shouldBe Color.Black
test("completePromotion to Knight executes move"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "8/4P3/8/8/8/8/k7/8 w - - 0 1")
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Knight)
engine.isPendingPromotion shouldBe false
engine.turn shouldBe Color.Black
test("promotion to Queen with discovered check emits CheckDetectedEvent"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
// FEN: white pawn e7, black king e6, white king e1
EngineTestHelpers.loadFen(engine, "8/4P3/4k3/8/8/8/8/4K3 w - - 0 1")
observer.clear()
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Queen)
observer.hasEvent[CheckDetectedEvent] shouldBe true
test("promotion to Queen with checkmate emits CheckmateEvent"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
// FEN: known promotion-mate pattern
EngineTestHelpers.loadFen(engine, "k7/7P/1K6/8/8/8/8/8 w - - 0 1")
observer.clear()
engine.processUserInput("h7h8")
engine.completePromotion(PromotionPiece.Queen)
observer.hasEvent[CheckmateEvent] shouldBe true
test("undo promotion emits notation with piece suffix"):
val engine = EngineTestHelpers.makeEngine()
val observer = new EngineTestHelpers.MockObserver()
engine.subscribe(observer)
EngineTestHelpers.loadFen(engine, "8/4P3/4k3/8/8/8/8/8 w - - 0 1")
engine.processUserInput("e7e8")
engine.completePromotion(PromotionPiece.Bishop)
observer.clear()
engine.undo()
val evt = observer.getEvent[MoveUndoneEvent]
evt.isDefined shouldBe true
evt.get.pgnNotation shouldBe "e8=B"
test("black pawn promotion executes"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "8/8/8/8/8/4k3/4p3/8 b - - 0 1")
engine.processUserInput("e2e1")
engine.isPendingPromotion shouldBe true
engine.completePromotion(PromotionPiece.Queen)
engine.isPendingPromotion shouldBe false
engine.turn shouldBe Color.White
// ── Promotion capturing ────────────────────────────────────────
test("pawn promotion with capture executes"):
val engine = EngineTestHelpers.makeEngine()
EngineTestHelpers.loadFen(engine, "3n4/4P3/4k3/8/8/8/8/4K3 w - - 0 1")
engine.processUserInput("e7d8")
engine.isPendingPromotion shouldBe true
@@ -1,351 +0,0 @@
package de.nowchess.chess.engine
import scala.collection.mutable
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.observer.{Observer, GameEvent, MoveExecutedEvent, CheckDetectedEvent, BoardResetEvent, InvalidMoveEvent, FiftyMoveRuleAvailableEvent, DrawClaimedEvent, MoveUndoneEvent, MoveRedoneEvent}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameEngineTest extends AnyFunSuite with Matchers:
test("GameEngine starts with initial board state"):
val engine = new GameEngine()
engine.board shouldBe Board.initial
engine.history shouldBe GameHistory.empty
engine.turn shouldBe Color.White
test("GameEngine accepts Observer subscription"):
val engine = new GameEngine()
val mockObserver = new MockObserver()
engine.subscribe(mockObserver)
engine.observerCount shouldBe 1
test("GameEngine notifies observers on valid move"):
val engine = new GameEngine()
val mockObserver = new MockObserver()
engine.subscribe(mockObserver)
engine.processUserInput("e2e4")
mockObserver.events.size shouldBe 1
mockObserver.events.head shouldBe a[MoveExecutedEvent]
test("GameEngine updates state after valid move"):
val engine = new GameEngine()
val initialTurn = engine.turn
engine.processUserInput("e2e4")
engine.turn shouldNot be(initialTurn)
engine.turn shouldBe Color.Black
test("GameEngine notifies observers on invalid move"):
val engine = new GameEngine()
val mockObserver = new MockObserver()
engine.subscribe(mockObserver)
engine.processUserInput("invalid_move")
mockObserver.events.size shouldBe 1
test("GameEngine notifies multiple observers"):
val engine = new GameEngine()
val observer1 = new MockObserver()
val observer2 = new MockObserver()
engine.subscribe(observer1)
engine.subscribe(observer2)
engine.processUserInput("e2e4")
observer1.events.size shouldBe 1
observer2.events.size shouldBe 1
test("GameEngine allows observer unsubscription"):
val engine = new GameEngine()
val mockObserver = new MockObserver()
engine.subscribe(mockObserver)
engine.unsubscribe(mockObserver)
engine.observerCount shouldBe 0
test("GameEngine unsubscribed observer receives no events"):
val engine = new GameEngine()
val mockObserver = new MockObserver()
engine.subscribe(mockObserver)
engine.unsubscribe(mockObserver)
engine.processUserInput("e2e4")
mockObserver.events.size shouldBe 0
test("GameEngine reset notifies observers and resets state"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val observer = new MockObserver()
engine.subscribe(observer)
engine.reset()
engine.board shouldBe Board.initial
engine.turn shouldBe Color.White
observer.events.size shouldBe 1
test("GameEngine processes sequence of moves"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
observer.events.size shouldBe 2
engine.turn shouldBe Color.White
test("GameEngine is thread-safe for synchronized operations"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
val t = new Thread(() => engine.processUserInput("e2e4"))
t.start()
t.join()
observer.events.size shouldBe 1
test("GameEngine canUndo returns false initially"):
val engine = new GameEngine()
engine.canUndo shouldBe false
test("GameEngine canUndo returns true after move"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.canUndo shouldBe true
test("GameEngine canRedo returns false initially"):
val engine = new GameEngine()
engine.canRedo shouldBe false
test("GameEngine undo restores previous state"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val boardAfterMove = engine.board
engine.undo()
engine.board shouldBe Board.initial
engine.turn shouldBe Color.White
test("GameEngine undo notifies observers"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val observer = new MockObserver()
engine.subscribe(observer)
observer.events.clear()
engine.undo()
observer.events.size shouldBe 1
observer.events.head shouldBe a[MoveUndoneEvent]
test("GameEngine redo replays undone move"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val boardAfterMove = engine.board
engine.undo()
engine.redo()
engine.board shouldBe boardAfterMove
engine.turn shouldBe Color.Black
test("GameEngine canUndo false when nothing to undo"):
val engine = new GameEngine()
engine.canUndo shouldBe false
engine.processUserInput("e2e4")
engine.undo()
engine.canUndo shouldBe false
test("GameEngine canRedo true after undo"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.undo()
engine.canRedo shouldBe true
test("GameEngine canRedo false after redo"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.undo()
engine.redo()
engine.canRedo shouldBe false
test("GameEngine undo on empty history sends invalid event"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.undo()
observer.events.size shouldBe 1
observer.events.head shouldBe a[InvalidMoveEvent]
test("GameEngine redo on empty redo sends invalid event"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.redo()
observer.events.size shouldBe 1
observer.events.head shouldBe a[InvalidMoveEvent]
test("GameEngine undo via processUserInput"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val boardAfterMove = engine.board
engine.processUserInput("undo")
engine.board shouldBe Board.initial
test("GameEngine redo via processUserInput"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
val boardAfterMove = engine.board
engine.processUserInput("undo")
engine.processUserInput("redo")
engine.board shouldBe boardAfterMove
test("GameEngine handles empty input"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("")
observer.events.size shouldBe 1
observer.events.head shouldBe a[InvalidMoveEvent]
test("GameEngine multiple undo/redo sequence"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.processUserInput("g1f3")
engine.turn shouldBe Color.Black
engine.undo()
engine.turn shouldBe Color.White
engine.undo()
engine.turn shouldBe Color.Black
engine.undo()
engine.turn shouldBe Color.White
engine.board shouldBe Board.initial
test("GameEngine redo after multiple undos"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.processUserInput("g1f3")
engine.undo()
engine.undo()
engine.undo()
engine.redo()
engine.turn shouldBe Color.Black
engine.redo()
engine.turn shouldBe Color.White
engine.redo()
engine.turn shouldBe Color.Black
test("GameEngine new move after undo clears redo history"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
engine.undo()
engine.canRedo shouldBe true
engine.processUserInput("e7e6") // Different move
engine.canRedo shouldBe false
test("GameEngine command history tracking"):
val engine = new GameEngine()
engine.commandHistory.size shouldBe 0
engine.processUserInput("e2e4")
engine.commandHistory.size shouldBe 1
engine.processUserInput("e7e5")
engine.commandHistory.size shouldBe 2
test("GameEngine quit input"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
val initialEvents = observer.events.size
engine.processUserInput("quit")
// quit should not produce an event
observer.events.size shouldBe initialEvents
test("GameEngine quit via q"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
val initialEvents = observer.events.size
engine.processUserInput("q")
observer.events.size shouldBe initialEvents
test("GameEngine undo notifies with MoveUndoneEvent after successful undo"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
val observer = new MockObserver()
engine.subscribe(observer)
observer.events.clear()
engine.undo()
// Should have received a MoveUndoneEvent on undo
observer.events.size should be > 0
observer.events.exists(_.isInstanceOf[MoveUndoneEvent]) shouldBe true
test("GameEngine redo notifies with MoveRedoneEvent after successful redo"):
val engine = new GameEngine()
engine.processUserInput("e2e4")
engine.processUserInput("e7e5")
val boardAfterSecondMove = engine.board
engine.undo()
val observer = new MockObserver()
engine.subscribe(observer)
observer.events.clear()
engine.redo()
// Should have received a MoveRedoneEvent for the redo
observer.events.size shouldBe 1
observer.events.head shouldBe a[MoveRedoneEvent]
engine.board shouldBe boardAfterSecondMove
engine.turn shouldBe Color.White
// ──── 50-move rule ───────────────────────────────────────────────────
test("GameEngine: 'draw' rejected when halfMoveClock < 100"):
val engine = new GameEngine()
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("draw")
observer.events.size shouldBe 1
observer.events.head shouldBe a[InvalidMoveEvent]
test("GameEngine: 'draw' accepted and fires DrawClaimedEvent when halfMoveClock >= 100"):
val engine = new GameEngine(initialHistory = GameHistory(halfMoveClock = 100))
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("draw")
observer.events.size shouldBe 1
observer.events.head shouldBe a[DrawClaimedEvent]
test("GameEngine: state resets to initial after draw claimed"):
val engine = new GameEngine(initialHistory = GameHistory(halfMoveClock = 100))
engine.processUserInput("draw")
engine.board shouldBe Board.initial
engine.history shouldBe GameHistory.empty
engine.turn shouldBe Color.White
test("GameEngine: FiftyMoveRuleAvailableEvent fired when move brings clock to 100"):
// Start at clock 99; a knight move (non-pawn, non-capture) increments to 100
val engine = new GameEngine(initialHistory = GameHistory(halfMoveClock = 99))
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("g1f3") // knight move on initial board
// Should receive MoveExecutedEvent AND FiftyMoveRuleAvailableEvent
observer.events.exists(_.isInstanceOf[FiftyMoveRuleAvailableEvent]) shouldBe true
test("GameEngine: FiftyMoveRuleAvailableEvent not fired when clock is below 100 after move"):
val engine = new GameEngine(initialHistory = GameHistory(halfMoveClock = 5))
val observer = new MockObserver()
engine.subscribe(observer)
engine.processUserInput("g1f3")
observer.events.exists(_.isInstanceOf[FiftyMoveRuleAvailableEvent]) shouldBe false
// Mock Observer for testing
private class MockObserver extends Observer:
val events = mutable.ListBuffer[GameEvent]()
override def onGameEvent(event: GameEvent): Unit =
events += event
@@ -1,110 +0,0 @@
package de.nowchess.chess.command
import de.nowchess.api.board.{Square, File, Rank, Board, Color}
import de.nowchess.chess.logic.GameHistory
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class MoveCommandDefaultsTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
// Tests for MoveCommand with default parameter values
test("MoveCommand with no moveResult defaults to None"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4)
)
cmd.moveResult shouldBe None
cmd.execute() shouldBe false
test("MoveCommand with no previousBoard defaults to None"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4)
)
cmd.previousBoard shouldBe None
cmd.undo() shouldBe false
test("MoveCommand with no previousHistory defaults to None"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4)
)
cmd.previousHistory shouldBe None
cmd.undo() shouldBe false
test("MoveCommand with no previousTurn defaults to None"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4)
)
cmd.previousTurn shouldBe None
cmd.undo() shouldBe false
test("MoveCommand description is always returned"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4)
)
cmd.description shouldBe "Move from e2 to e4"
test("MoveCommand execute returns false when moveResult is None"):
val cmd = MoveCommand(
from = sq(File.A, Rank.R1),
to = sq(File.B, Rank.R3)
)
cmd.execute() shouldBe false
test("MoveCommand undo returns false when any previous state is None"):
// Missing previousBoard
val cmd1 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)),
previousBoard = None,
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
)
cmd1.undo() shouldBe false
// Missing previousHistory
val cmd2 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)),
previousBoard = Some(Board.initial),
previousHistory = None,
previousTurn = Some(Color.White)
)
cmd2.undo() shouldBe false
// Missing previousTurn
val cmd3 = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)),
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = None
)
cmd3.undo() shouldBe false
test("MoveCommand execute returns true when moveResult is defined"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None))
)
cmd.execute() shouldBe true
test("MoveCommand undo returns true when all previous states are defined"):
val cmd = MoveCommand(
from = sq(File.E, Rank.R2),
to = sq(File.E, Rank.R4),
moveResult = Some(MoveResult.Successful(Board.initial, GameHistory.empty, Color.White, None)),
previousBoard = Some(Board.initial),
previousHistory = Some(GameHistory.empty),
previousTurn = Some(Color.White)
)
cmd.undo() shouldBe true
@@ -1,70 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
import de.nowchess.api.game.CastlingRights
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class CastlingRightsCalculatorTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
test("Empty history gives full castling rights"):
val rights = CastlingRightsCalculator.deriveCastlingRights(GameHistory.empty, Color.White)
rights shouldBe CastlingRights.Both
test("White loses kingside rights after h1 rook moves"):
val history = GameHistory.empty.addMove(sq(File.H, Rank.R1), sq(File.H, Rank.R2))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.White)
rights.kingSide shouldBe false
rights.queenSide shouldBe true
test("White loses queenside rights after a1 rook moves"):
val history = GameHistory.empty.addMove(sq(File.A, Rank.R1), sq(File.A, Rank.R2))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.White)
rights.queenSide shouldBe false
rights.kingSide shouldBe true
test("White loses all rights after king moves"):
val history = GameHistory.empty.addMove(sq(File.E, Rank.R1), sq(File.E, Rank.R2))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.White)
rights shouldBe CastlingRights.None
test("Black loses kingside rights after h8 rook moves"):
val history = GameHistory.empty.addMove(sq(File.H, Rank.R8), sq(File.H, Rank.R7))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.Black)
rights.kingSide shouldBe false
rights.queenSide shouldBe true
test("Black loses queenside rights after a8 rook moves"):
val history = GameHistory.empty.addMove(sq(File.A, Rank.R8), sq(File.A, Rank.R7))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.Black)
rights.queenSide shouldBe false
rights.kingSide shouldBe true
test("Black loses all rights after king moves"):
val history = GameHistory.empty.addMove(sq(File.E, Rank.R8), sq(File.E, Rank.R7))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.Black)
rights shouldBe CastlingRights.None
test("Castle move revokes all castling rights"):
val history = GameHistory.empty.addMove(
sq(File.E, Rank.R1),
sq(File.G, Rank.R1),
Some(CastleSide.Kingside)
)
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.White)
rights shouldBe CastlingRights.None
test("Other pieces moving does not revoke castling rights"):
val history = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.White)
rights shouldBe CastlingRights.Both
test("Multiple moves preserve white kingside but lose queenside"):
val history = GameHistory.empty
.addMove(sq(File.A, Rank.R1), sq(File.A, Rank.R2)) // White queenside rook moves
.addMove(sq(File.E, Rank.R7), sq(File.E, Rank.R5)) // Black pawn moves
val rights = CastlingRightsCalculator.deriveCastlingRights(history, Color.White)
rights.kingSide shouldBe true
rights.queenSide shouldBe false
@@ -1,101 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class EnPassantCalculatorTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
private def board(entries: (Square, Piece)*): Board = Board(entries.toMap)
// ──── enPassantTarget ────────────────────────────────────────────────
test("enPassantTarget returns None for empty history"):
val b = board(sq(File.E, Rank.R4) -> Piece.WhitePawn)
EnPassantCalculator.enPassantTarget(b, GameHistory.empty) shouldBe None
test("enPassantTarget returns None when last move was a single pawn push"):
val b = board(sq(File.E, Rank.R3) -> Piece.WhitePawn)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R3))
EnPassantCalculator.enPassantTarget(b, h) shouldBe None
test("enPassantTarget returns None when last move was not a pawn"):
val b = board(sq(File.E, Rank.R4) -> Piece.WhiteRook)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
EnPassantCalculator.enPassantTarget(b, h) shouldBe None
test("enPassantTarget returns e3 after white pawn double push e2-e4"):
val b = board(sq(File.E, Rank.R4) -> Piece.WhitePawn)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
EnPassantCalculator.enPassantTarget(b, h) shouldBe Some(sq(File.E, Rank.R3))
test("enPassantTarget returns e6 after black pawn double push e7-e5"):
val b = board(sq(File.E, Rank.R5) -> Piece.BlackPawn)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R7), sq(File.E, Rank.R5))
EnPassantCalculator.enPassantTarget(b, h) shouldBe Some(sq(File.E, Rank.R6))
test("enPassantTarget returns d3 after white pawn double push d2-d4"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhitePawn)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R2), sq(File.D, Rank.R4))
EnPassantCalculator.enPassantTarget(b, h) shouldBe Some(sq(File.D, Rank.R3))
// ──── capturedPawnSquare ─────────────────────────────────────────────
test("capturedPawnSquare for white capturing on e6 returns e5"):
EnPassantCalculator.capturedPawnSquare(sq(File.E, Rank.R6), Color.White) shouldBe sq(File.E, Rank.R5)
test("capturedPawnSquare for black capturing on e3 returns e4"):
EnPassantCalculator.capturedPawnSquare(sq(File.E, Rank.R3), Color.Black) shouldBe sq(File.E, Rank.R4)
test("capturedPawnSquare for white capturing on d6 returns d5"):
EnPassantCalculator.capturedPawnSquare(sq(File.D, Rank.R6), Color.White) shouldBe sq(File.D, Rank.R5)
// ──── isEnPassant ────────────────────────────────────────────────────
test("isEnPassant returns true for valid white en passant capture"):
// White pawn on e5, black pawn just double-pushed to d5 (ep target = d6)
val b = board(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R7), sq(File.D, Rank.R5))
EnPassantCalculator.isEnPassant(b, h, sq(File.E, Rank.R5), sq(File.D, Rank.R6)) shouldBe true
test("isEnPassant returns true for valid black en passant capture"):
// Black pawn on d4, white pawn just double-pushed to e4 (ep target = e3)
val b = board(
sq(File.D, Rank.R4) -> Piece.BlackPawn,
sq(File.E, Rank.R4) -> Piece.WhitePawn
)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
EnPassantCalculator.isEnPassant(b, h, sq(File.D, Rank.R4), sq(File.E, Rank.R3)) shouldBe true
test("isEnPassant returns false when no en passant target in history"):
val b = board(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R6), sq(File.D, Rank.R5)) // single push
EnPassantCalculator.isEnPassant(b, h, sq(File.E, Rank.R5), sq(File.D, Rank.R6)) shouldBe false
test("isEnPassant returns false when piece at from is not a pawn"):
val b = board(
sq(File.E, Rank.R5) -> Piece.WhiteRook,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R7), sq(File.D, Rank.R5))
EnPassantCalculator.isEnPassant(b, h, sq(File.E, Rank.R5), sq(File.D, Rank.R6)) shouldBe false
test("isEnPassant returns false when to does not match ep target"):
val b = board(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R7), sq(File.D, Rank.R5))
EnPassantCalculator.isEnPassant(b, h, sq(File.E, Rank.R5), sq(File.E, Rank.R6)) shouldBe false
test("isEnPassant returns false when from square is empty"):
val b = board(sq(File.D, Rank.R5) -> Piece.BlackPawn)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R7), sq(File.D, Rank.R5))
EnPassantCalculator.isEnPassant(b, h, sq(File.E, Rank.R5), sq(File.D, Rank.R6)) shouldBe false
@@ -1,104 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
import de.nowchess.api.move.PromotionPiece
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameHistoryTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
test("GameHistory starts empty"):
val history = GameHistory.empty
history.moves shouldBe empty
test("GameHistory can add a move"):
val history = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
history.moves should have length 1
history.moves.head.from shouldBe sq(File.E, Rank.R2)
history.moves.head.to shouldBe sq(File.E, Rank.R4)
history.moves.head.castleSide shouldBe None
test("GameHistory can add multiple moves in order"):
val h1 = GameHistory.empty
val h2 = h1.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
val h3 = h2.addMove(sq(File.C, Rank.R7), sq(File.C, Rank.R5))
h3.moves should have length 2
h3.moves(0).from shouldBe sq(File.E, Rank.R2)
h3.moves(1).from shouldBe sq(File.C, Rank.R7)
test("GameHistory can add a castle move"):
val history = GameHistory.empty.addMove(
sq(File.E, Rank.R1),
sq(File.G, Rank.R1),
Some(CastleSide.Kingside)
)
history.moves.head.castleSide shouldBe Some(CastleSide.Kingside)
test("GameHistory.addMove with two arguments uses None for castleSide default"):
val history = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
history.moves should have length 1
history.moves.head.castleSide shouldBe None
test("Move with promotion records the promotion piece"):
val move = HistoryMove(sq(File.E, Rank.R7), sq(File.E, Rank.R8), None, Some(PromotionPiece.Queen))
move.promotionPiece should be (Some(PromotionPiece.Queen))
test("Normal move has no promotion piece"):
val move = HistoryMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4), None, None)
move.promotionPiece should be (None)
test("addMove with promotion stores promotionPiece"):
val history = GameHistory.empty
val newHistory = history.addMove(sq(File.E, Rank.R7), sq(File.E, Rank.R8), None, Some(PromotionPiece.Rook))
newHistory.moves should have length 1
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Rook))
test("addMove with castleSide only uses promotionPiece default (None)"):
val history = GameHistory.empty
// With overload 3 removed, this uses the 4-param version and triggers addMove$default$4
val newHistory = history.addMove(sq(File.E, Rank.R1), sq(File.G, Rank.R1), Some(CastleSide.Kingside))
newHistory.moves should have length 1
newHistory.moves.head.castleSide should be (Some(CastleSide.Kingside))
newHistory.moves.head.promotionPiece should be (None)
test("addMove using named parameters with only promotion, using castleSide default"):
val history = GameHistory.empty
val newHistory = history.addMove(from = sq(File.E, Rank.R7), to = sq(File.E, Rank.R8), promotionPiece = Some(PromotionPiece.Queen))
newHistory.moves should have length 1
newHistory.moves.head.castleSide should be (None)
newHistory.moves.head.promotionPiece should be (Some(PromotionPiece.Queen))
// ──── half-move clock ────────────────────────────────────────────────
test("halfMoveClock starts at 0"):
GameHistory.empty.halfMoveClock shouldBe 0
test("halfMoveClock increments on a non-pawn non-capture move"):
val h = GameHistory.empty.addMove(sq(File.G, Rank.R1), sq(File.F, Rank.R3))
h.halfMoveClock shouldBe 1
test("halfMoveClock resets to 0 on a pawn move"):
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4), wasPawnMove = true)
h.halfMoveClock shouldBe 0
test("halfMoveClock resets to 0 on a capture"):
val h = GameHistory.empty.addMove(sq(File.E, Rank.R5), sq(File.D, Rank.R6), wasCapture = true)
h.halfMoveClock shouldBe 0
test("halfMoveClock resets to 0 when both wasPawnMove and wasCapture are true"):
val h = GameHistory.empty.addMove(sq(File.E, Rank.R5), sq(File.D, Rank.R6), wasPawnMove = true, wasCapture = true)
h.halfMoveClock shouldBe 0
test("halfMoveClock carries across multiple moves"):
val h = GameHistory.empty
.addMove(sq(File.G, Rank.R1), sq(File.F, Rank.R3)) // +1 → 1
.addMove(sq(File.G, Rank.R8), sq(File.F, Rank.R6)) // +1 → 2
.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4), wasPawnMove = true) // reset → 0
.addMove(sq(File.B, Rank.R1), sq(File.C, Rank.R3)) // +1 → 1
h.halfMoveClock shouldBe 1
test("GameHistory can be initialised with a non-zero halfMoveClock"):
val h = GameHistory(halfMoveClock = 42)
h.halfMoveClock shouldBe 42
@@ -1,161 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.*
import de.nowchess.api.game.CastlingRights
import de.nowchess.chess.logic.GameHistory
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class GameRulesTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
private def board(entries: (Square, Piece)*): Board = Board(entries.toMap)
/** Wrap a board in a GameContext with no castling rights — for non-castling tests. */
private def testLegalMoves(entries: (Square, Piece)*)(color: Color): Set[(Square, Square)] =
GameRules.legalMoves(Board(entries.toMap), GameHistory.empty, color)
private def testGameStatus(entries: (Square, Piece)*)(color: Color): PositionStatus =
GameRules.gameStatus(Board(entries.toMap), GameHistory.empty, color)
// ──── isInCheck ──────────────────────────────────────────────────────
test("isInCheck: king attacked by enemy rook on same rank"):
// White King E1, Black Rook A1 — rook slides along rank 1 to E1
val b = board(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R1) -> Piece.BlackRook
)
GameRules.isInCheck(b, Color.White) shouldBe true
test("isInCheck: king not attacked"):
// Black Rook A3 does not cover E1
val b = board(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R3) -> Piece.BlackRook
)
GameRules.isInCheck(b, Color.White) shouldBe false
test("isInCheck: no king on board returns false"):
val b = board(sq(File.A, Rank.R1) -> Piece.BlackRook)
GameRules.isInCheck(b, Color.White) shouldBe false
// ──── legalMoves ─────────────────────────────────────────────────────
test("legalMoves: move that exposes own king to rook is excluded"):
// White King E1, White Rook E4 (pinned on E-file), Black Rook E8
// Moving the White Rook off the E-file would expose the king
val moves = testLegalMoves(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.E, Rank.R4) -> Piece.WhiteRook,
sq(File.E, Rank.R8) -> Piece.BlackRook
)(Color.White)
moves should not contain (sq(File.E, Rank.R4) -> sq(File.D, Rank.R4))
test("legalMoves: move that blocks check is included"):
// White King E1 in check from Black Rook E8; White Rook A5 can interpose on E5
val moves = testLegalMoves(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R5) -> Piece.WhiteRook,
sq(File.E, Rank.R8) -> Piece.BlackRook
)(Color.White)
moves should contain(sq(File.A, Rank.R5) -> sq(File.E, Rank.R5))
// ──── gameStatus ──────────────────────────────────────────────────────
test("gameStatus: checkmate returns Mated"):
// White Qh8, Ka6; Black Ka8
// Qh8 attacks Ka8 along rank 8; all escape squares covered (spec-verified position)
testGameStatus(
sq(File.H, Rank.R8) -> Piece.WhiteQueen,
sq(File.A, Rank.R6) -> Piece.WhiteKing,
sq(File.A, Rank.R8) -> Piece.BlackKing
)(Color.Black) shouldBe PositionStatus.Mated
test("gameStatus: stalemate returns Drawn"):
// White Qb6, Kc6; Black Ka8
// Black king has no legal moves and is not in check (spec-verified position)
testGameStatus(
sq(File.B, Rank.R6) -> Piece.WhiteQueen,
sq(File.C, Rank.R6) -> Piece.WhiteKing,
sq(File.A, Rank.R8) -> Piece.BlackKing
)(Color.Black) shouldBe PositionStatus.Drawn
test("gameStatus: king in check with legal escape returns InCheck"):
// White Ra8 attacks Black Ke8 along rank 8; king can escape to d7, e7, f7
testGameStatus(
sq(File.A, Rank.R8) -> Piece.WhiteRook,
sq(File.E, Rank.R8) -> Piece.BlackKing
)(Color.Black) shouldBe PositionStatus.InCheck
test("gameStatus: normal starting position returns Normal"):
GameRules.gameStatus(Board.initial, GameHistory.empty, Color.White) shouldBe PositionStatus.Normal
test("legalMoves: includes castling destination when available"):
val b = board(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
)
GameRules.legalMoves(b, GameHistory.empty, Color.White) should contain(sq(File.E, Rank.R1) -> sq(File.G, Rank.R1))
test("legalMoves: excludes castling when king is in check"):
val b = board(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.E, Rank.R8) -> Piece.BlackRook,
sq(File.A, Rank.R8) -> Piece.BlackKing
)
GameRules.legalMoves(b, GameHistory.empty, Color.White) should not contain (sq(File.E, Rank.R1) -> sq(File.G, Rank.R1))
test("gameStatus: returns Normal (not Drawn) when castling is the only legal move"):
// White King e1, Rook h1 (kingside castling available).
// Black Rooks d2 and f2 box the king: d1 attacked by d2, e2 attacked by both,
// f1 attacked by f2. King cannot move to any adjacent square without entering
// an attacked square or an enemy piece. Only legal move: castle to g1.
val b = board(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.H, Rank.R1) -> Piece.WhiteRook,
sq(File.D, Rank.R2) -> Piece.BlackRook,
sq(File.F, Rank.R2) -> Piece.BlackRook,
sq(File.A, Rank.R8) -> Piece.BlackKing
)
// No history means castling rights are intact
GameRules.gameStatus(b, GameHistory.empty, Color.White) shouldBe PositionStatus.Normal
test("CastleSide.withCastle correctly positions pieces for Queenside castling"):
// Directly test the withCastle extension for Queenside (coverage gap on line 10)
val b = board(
sq(File.E, Rank.R1) -> Piece.WhiteKing,
sq(File.A, Rank.R1) -> Piece.WhiteRook,
sq(File.H, Rank.R8) -> Piece.BlackKing
)
val result = b.withCastle(Color.White, CastleSide.Queenside)
result.pieceAt(sq(File.C, Rank.R1)) shouldBe Some(Piece.WhiteKing)
result.pieceAt(sq(File.D, Rank.R1)) shouldBe Some(Piece.WhiteRook)
result.pieceAt(sq(File.E, Rank.R1)) shouldBe None
result.pieceAt(sq(File.A, Rank.R1)) shouldBe None
test("CastleSide.withCastle correctly positions pieces for Black Kingside castling"):
val b = board(
sq(File.E, Rank.R8) -> Piece.BlackKing,
sq(File.H, Rank.R8) -> Piece.BlackRook,
sq(File.A, Rank.R1) -> Piece.WhiteKing
)
val result = b.withCastle(Color.Black, CastleSide.Kingside)
result.pieceAt(sq(File.G, Rank.R8)) shouldBe Some(Piece.BlackKing)
result.pieceAt(sq(File.F, Rank.R8)) shouldBe Some(Piece.BlackRook)
result.pieceAt(sq(File.E, Rank.R8)) shouldBe None
result.pieceAt(sq(File.H, Rank.R8)) shouldBe None
test("CastleSide.withCastle correctly positions pieces for Black Queenside castling"):
val b = board(
sq(File.E, Rank.R8) -> Piece.BlackKing,
sq(File.A, Rank.R8) -> Piece.BlackRook,
sq(File.A, Rank.R1) -> Piece.WhiteKing
)
val result = b.withCastle(Color.Black, CastleSide.Queenside)
result.pieceAt(sq(File.C, Rank.R8)) shouldBe Some(Piece.BlackKing)
result.pieceAt(sq(File.D, Rank.R8)) shouldBe Some(Piece.BlackRook)
result.pieceAt(sq(File.E, Rank.R8)) shouldBe None
result.pieceAt(sq(File.A, Rank.R8)) shouldBe None
@@ -1,280 +0,0 @@
package de.nowchess.chess.logic
import de.nowchess.api.board.{Board, Color, File, Piece, Rank, Square}
import de.nowchess.api.game.CastlingRights
import de.nowchess.chess.logic.{CastleSide, GameHistory}
import de.nowchess.chess.notation.FenParser
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class MoveValidatorTest extends AnyFunSuite with Matchers:
private def sq(f: File, r: Rank): Square = Square(f, r)
private def board(entries: (Square, Piece)*): Board = Board(entries.toMap)
// ──── Empty square ───────────────────────────────────────────────────
test("legalTargets returns empty set when no piece at from square"):
MoveValidator.legalTargets(Board.initial, sq(File.E, Rank.R4)) shouldBe empty
// ──── isLegal delegates to legalTargets ──────────────────────────────
test("isLegal returns true for a valid pawn move"):
MoveValidator.isLegal(Board.initial, sq(File.E, Rank.R2), sq(File.E, Rank.R4)) shouldBe true
test("isLegal returns false for an invalid move"):
MoveValidator.isLegal(Board.initial, sq(File.E, Rank.R2), sq(File.E, Rank.R5)) shouldBe false
// ──── Pawn – White ───────────────────────────────────────────────────
test("white pawn on starting rank can move forward one square"):
val b = board(sq(File.E, Rank.R2) -> Piece.WhitePawn)
MoveValidator.legalTargets(b, sq(File.E, Rank.R2)) should contain(sq(File.E, Rank.R3))
test("white pawn on starting rank can move forward two squares"):
val b = board(sq(File.E, Rank.R2) -> Piece.WhitePawn)
MoveValidator.legalTargets(b, sq(File.E, Rank.R2)) should contain(sq(File.E, Rank.R4))
test("white pawn not on starting rank cannot move two squares"):
val b = board(sq(File.E, Rank.R3) -> Piece.WhitePawn)
MoveValidator.legalTargets(b, sq(File.E, Rank.R3)) should not contain sq(File.E, Rank.R5)
test("white pawn is blocked by piece directly in front, and cannot jump over it"):
val b = board(
sq(File.E, Rank.R2) -> Piece.WhitePawn,
sq(File.E, Rank.R3) -> Piece.BlackPawn
)
val targets = MoveValidator.legalTargets(b, sq(File.E, Rank.R2))
targets should not contain sq(File.E, Rank.R3)
targets should not contain sq(File.E, Rank.R4)
test("white pawn on starting rank cannot move two squares if destination square is occupied"):
val b = board(
sq(File.E, Rank.R2) -> Piece.WhitePawn,
sq(File.E, Rank.R4) -> Piece.BlackPawn
)
val targets = MoveValidator.legalTargets(b, sq(File.E, Rank.R2))
targets should contain(sq(File.E, Rank.R3))
targets should not contain sq(File.E, Rank.R4)
test("white pawn can capture diagonally when enemy piece is present"):
val b = board(
sq(File.E, Rank.R2) -> Piece.WhitePawn,
sq(File.D, Rank.R3) -> Piece.BlackPawn
)
MoveValidator.legalTargets(b, sq(File.E, Rank.R2)) should contain(sq(File.D, Rank.R3))
test("white pawn cannot capture diagonally when no enemy piece is present"):
val b = board(sq(File.E, Rank.R2) -> Piece.WhitePawn)
MoveValidator.legalTargets(b, sq(File.E, Rank.R2)) should not contain sq(File.D, Rank.R3)
test("white pawn at A-file does not generate diagonal to the left off the board"):
val b = board(sq(File.A, Rank.R2) -> Piece.WhitePawn)
val targets = MoveValidator.legalTargets(b, sq(File.A, Rank.R2))
targets should contain(sq(File.A, Rank.R3))
targets should contain(sq(File.A, Rank.R4))
targets.size shouldBe 2
// ──── Pawn – Black ───────────────────────────────────────────────────
test("black pawn on starting rank can move forward one and two squares"):
val b = board(sq(File.E, Rank.R7) -> Piece.BlackPawn)
val targets = MoveValidator.legalTargets(b, sq(File.E, Rank.R7))
targets should contain(sq(File.E, Rank.R6))
targets should contain(sq(File.E, Rank.R5))
test("black pawn not on starting rank cannot move two squares"):
val b = board(sq(File.E, Rank.R6) -> Piece.BlackPawn)
MoveValidator.legalTargets(b, sq(File.E, Rank.R6)) should not contain sq(File.E, Rank.R4)
test("black pawn can capture diagonally when enemy piece is present"):
val b = board(
sq(File.E, Rank.R7) -> Piece.BlackPawn,
sq(File.F, Rank.R6) -> Piece.WhitePawn
)
MoveValidator.legalTargets(b, sq(File.E, Rank.R7)) should contain(sq(File.F, Rank.R6))
// ──── Knight ─────────────────────────────────────────────────────────
test("knight in center has 8 possible moves"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhiteKnight)
MoveValidator.legalTargets(b, sq(File.D, Rank.R4)).size shouldBe 8
test("knight in corner has only 2 possible moves"):
val b = board(sq(File.A, Rank.R1) -> Piece.WhiteKnight)
MoveValidator.legalTargets(b, sq(File.A, Rank.R1)).size shouldBe 2
test("knight cannot land on own piece"):
val b = board(
sq(File.D, Rank.R4) -> Piece.WhiteKnight,
sq(File.F, Rank.R5) -> Piece.WhiteRook
)
MoveValidator.legalTargets(b, sq(File.D, Rank.R4)) should not contain sq(File.F, Rank.R5)
test("knight can capture enemy piece"):
val b = board(
sq(File.D, Rank.R4) -> Piece.WhiteKnight,
sq(File.F, Rank.R5) -> Piece.BlackRook
)
MoveValidator.legalTargets(b, sq(File.D, Rank.R4)) should contain(sq(File.F, Rank.R5))
// ──── Bishop ─────────────────────────────────────────────────────────
test("bishop slides diagonally across an empty board"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhiteBishop)
val targets = MoveValidator.legalTargets(b, sq(File.D, Rank.R4))
targets should contain(sq(File.E, Rank.R5))
targets should contain(sq(File.H, Rank.R8))
targets should contain(sq(File.C, Rank.R3))
targets should contain(sq(File.A, Rank.R1))
test("bishop is blocked by own piece and squares beyond are unreachable"):
val b = board(
sq(File.D, Rank.R4) -> Piece.WhiteBishop,
sq(File.F, Rank.R6) -> Piece.WhiteRook
)
val targets = MoveValidator.legalTargets(b, sq(File.D, Rank.R4))
targets should contain(sq(File.E, Rank.R5))
targets should not contain sq(File.F, Rank.R6)
targets should not contain sq(File.G, Rank.R7)
test("bishop captures enemy piece and cannot slide further"):
val b = board(
sq(File.D, Rank.R4) -> Piece.WhiteBishop,
sq(File.F, Rank.R6) -> Piece.BlackRook
)
val targets = MoveValidator.legalTargets(b, sq(File.D, Rank.R4))
targets should contain(sq(File.E, Rank.R5))
targets should contain(sq(File.F, Rank.R6))
targets should not contain sq(File.G, Rank.R7)
// ──── Rook ───────────────────────────────────────────────────────────
test("rook slides orthogonally across an empty board"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhiteRook)
val targets = MoveValidator.legalTargets(b, sq(File.D, Rank.R4))
targets should contain(sq(File.D, Rank.R8))
targets should contain(sq(File.D, Rank.R1))
targets should contain(sq(File.A, Rank.R4))
targets should contain(sq(File.H, Rank.R4))
test("rook is blocked by own piece and squares beyond are unreachable"):
val b = board(
sq(File.A, Rank.R1) -> Piece.WhiteRook,
sq(File.C, Rank.R1) -> Piece.WhitePawn
)
val targets = MoveValidator.legalTargets(b, sq(File.A, Rank.R1))
targets should contain(sq(File.B, Rank.R1))
targets should not contain sq(File.C, Rank.R1)
targets should not contain sq(File.D, Rank.R1)
test("rook captures enemy piece and cannot slide further"):
val b = board(
sq(File.A, Rank.R1) -> Piece.WhiteRook,
sq(File.C, Rank.R1) -> Piece.BlackPawn
)
val targets = MoveValidator.legalTargets(b, sq(File.A, Rank.R1))
targets should contain(sq(File.B, Rank.R1))
targets should contain(sq(File.C, Rank.R1))
targets should not contain sq(File.D, Rank.R1)
// ──── Queen ──────────────────────────────────────────────────────────
test("queen combines rook and bishop movement for 27 squares from d4"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhiteQueen)
val targets = MoveValidator.legalTargets(b, sq(File.D, Rank.R4))
targets should contain(sq(File.D, Rank.R8))
targets should contain(sq(File.H, Rank.R4))
targets should contain(sq(File.H, Rank.R8))
targets should contain(sq(File.A, Rank.R1))
targets.size shouldBe 27
// ──── King ───────────────────────────────────────────────────────────
test("king moves one step in all 8 directions from center"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhiteKing)
MoveValidator.legalTargets(b, sq(File.D, Rank.R4)).size shouldBe 8
test("king at corner has only 3 reachable squares"):
val b = board(sq(File.A, Rank.R1) -> Piece.WhiteKing)
MoveValidator.legalTargets(b, sq(File.A, Rank.R1)).size shouldBe 3
test("king cannot capture own piece"):
val b = board(
sq(File.D, Rank.R4) -> Piece.WhiteKing,
sq(File.E, Rank.R4) -> Piece.WhiteRook
)
MoveValidator.legalTargets(b, sq(File.D, Rank.R4)) should not contain sq(File.E, Rank.R4)
test("king can capture enemy piece"):
val b = board(
sq(File.D, Rank.R4) -> Piece.WhiteKing,
sq(File.E, Rank.R4) -> Piece.BlackRook
)
MoveValidator.legalTargets(b, sq(File.D, Rank.R4)) should contain(sq(File.E, Rank.R4))
// ──── Pawn en passant targets ──────────────────────────────────────
test("white pawn includes ep target in legal moves after black double push"):
// Black pawn just double-pushed to d5 (ep target = d6); white pawn on e5
val b = board(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R7), sq(File.D, Rank.R5))
MoveValidator.legalTargets(b, h, sq(File.E, Rank.R5)) should contain(sq(File.D, Rank.R6))
test("white pawn does not include ep target without a preceding double push"):
val b = board(
sq(File.E, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R6), sq(File.D, Rank.R5)) // single push
MoveValidator.legalTargets(b, h, sq(File.E, Rank.R5)) should not contain sq(File.D, Rank.R6)
test("black pawn includes ep target in legal moves after white double push"):
// White pawn just double-pushed to e4 (ep target = e3); black pawn on d4
val b = board(
sq(File.D, Rank.R4) -> Piece.BlackPawn,
sq(File.E, Rank.R4) -> Piece.WhitePawn
)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
MoveValidator.legalTargets(b, h, sq(File.D, Rank.R4)) should contain(sq(File.E, Rank.R3))
test("pawn on wrong file does not get ep target from adjacent double push"):
// White pawn on a5, black pawn double-pushed to d5 — a5 is not adjacent to d5
val b = board(
sq(File.A, Rank.R5) -> Piece.WhitePawn,
sq(File.D, Rank.R5) -> Piece.BlackPawn
)
val h = GameHistory.empty.addMove(sq(File.D, Rank.R7), sq(File.D, Rank.R5))
MoveValidator.legalTargets(b, h, sq(File.A, Rank.R5)) should not contain sq(File.D, Rank.R6)
// ──── History-aware legalTargets fallback for non-pawn non-king pieces ─────
test("legalTargets with history delegates to geometry-only for non-pawn non-king pieces"):
val b = board(sq(File.D, Rank.R4) -> Piece.WhiteRook)
val h = GameHistory.empty.addMove(sq(File.E, Rank.R2), sq(File.E, Rank.R4))
MoveValidator.legalTargets(b, h, sq(File.D, Rank.R4)) shouldBe MoveValidator.legalTargets(b, sq(File.D, Rank.R4))
// ──── isPromotionMove ────────────────────────────────────────────────
test("White pawn reaching R8 is a promotion move"):
val b = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
MoveValidator.isPromotionMove(b, Square(File.E, Rank.R7), Square(File.E, Rank.R8)) should be (true)
test("Black pawn reaching R1 is a promotion move"):
val b = FenParser.parseBoard("8/8/8/8/4K3/8/4p3/8").get
MoveValidator.isPromotionMove(b, Square(File.E, Rank.R2), Square(File.E, Rank.R1)) should be (true)
test("Pawn capturing to back rank is a promotion move"):
val b = FenParser.parseBoard("3q4/4P3/8/8/8/8/8/8").get
MoveValidator.isPromotionMove(b, Square(File.E, Rank.R7), Square(File.D, Rank.R8)) should be (true)
test("Pawn not reaching back rank is not a promotion move"):
val b = FenParser.parseBoard("8/8/8/4P3/8/8/8/8").get
MoveValidator.isPromotionMove(b, Square(File.E, Rank.R5), Square(File.E, Rank.R6)) should be (false)
test("Non-pawn piece is never a promotion move"):
val b = FenParser.parseBoard("8/8/8/4Q3/8/8/8/8").get
MoveValidator.isPromotionMove(b, Square(File.E, Rank.R5), Square(File.E, Rank.R8)) should be (false)
@@ -1,88 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.game.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class FenExporterTest extends AnyFunSuite with Matchers:
test("export initial position to FEN"):
val gameState = GameState.initial
val fen = FenExporter.gameStateToFen(gameState)
fen shouldBe "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"
test("export position after e4"):
val gameState = GameState(
piecePlacement = "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR",
activeColor = Color.Black,
castlingWhite = CastlingRights.Both,
castlingBlack = CastlingRights.Both,
enPassantTarget = Some(Square(File.E, Rank.R3)),
halfMoveClock = 0,
fullMoveNumber = 1,
status = GameStatus.InProgress
)
val fen = FenExporter.gameStateToFen(gameState)
fen shouldBe "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1"
test("export position with no castling"):
val gameState = GameState(
piecePlacement = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR",
activeColor = Color.White,
castlingWhite = CastlingRights.None,
castlingBlack = CastlingRights.None,
enPassantTarget = None,
halfMoveClock = 0,
fullMoveNumber = 1,
status = GameStatus.InProgress
)
val fen = FenExporter.gameStateToFen(gameState)
fen shouldBe "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w - - 0 1"
test("export position with partial castling"):
val gameState = GameState(
piecePlacement = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR",
activeColor = Color.White,
castlingWhite = CastlingRights(kingSide = true, queenSide = false),
castlingBlack = CastlingRights(kingSide = false, queenSide = true),
enPassantTarget = None,
halfMoveClock = 5,
fullMoveNumber = 3,
status = GameStatus.InProgress
)
val fen = FenExporter.gameStateToFen(gameState)
fen shouldBe "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w Kq - 5 3"
test("export position with en passant and move counts"):
val gameState = GameState(
piecePlacement = "rnbqkbnr/pp1ppppp/8/2pP4/8/8/PPPP1PPP/RNBQKBNR",
activeColor = Color.White,
castlingWhite = CastlingRights.Both,
castlingBlack = CastlingRights.Both,
enPassantTarget = Some(Square(File.C, Rank.R6)),
halfMoveClock = 2,
fullMoveNumber = 3,
status = GameStatus.InProgress
)
val fen = FenExporter.gameStateToFen(gameState)
fen shouldBe "rnbqkbnr/pp1ppppp/8/2pP4/8/8/PPPP1PPP/RNBQKBNR w KQkq c6 2 3"
test("halfMoveClock round-trips through FEN export and import"):
import de.nowchess.chess.logic.GameHistory
import de.nowchess.chess.notation.FenParser
val history = GameHistory(halfMoveClock = 42)
val gameState = GameState(
piecePlacement = FenExporter.boardToFen(de.nowchess.api.board.Board.initial),
activeColor = Color.White,
castlingWhite = CastlingRights.Both,
castlingBlack = CastlingRights.Both,
enPassantTarget = None,
halfMoveClock = history.halfMoveClock,
fullMoveNumber = 1,
status = GameStatus.InProgress
)
val fen = FenExporter.gameStateToFen(gameState)
FenParser.parseFen(fen) match
case Some(gs) => gs.halfMoveClock shouldBe 42
case None => fail("FEN parsing failed")
@@ -1,134 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.game.*
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class FenParserTest extends AnyFunSuite with Matchers:
test("parseBoard: initial position places pieces on correct squares"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR"
val board = FenParser.parseBoard(fen)
board.map(_.pieceAt(Square(File.E, Rank.R2))) shouldBe Some(Some(Piece.WhitePawn))
board.map(_.pieceAt(Square(File.E, Rank.R7))) shouldBe Some(Some(Piece.BlackPawn))
board.map(_.pieceAt(Square(File.E, Rank.R1))) shouldBe Some(Some(Piece.WhiteKing))
board.map(_.pieceAt(Square(File.E, Rank.R8))) shouldBe Some(Some(Piece.BlackKing))
test("parseBoard: empty board has no pieces"):
val fen = "8/8/8/8/8/8/8/8"
val board = FenParser.parseBoard(fen)
board shouldBe defined
board.get.pieces.size shouldBe 0
test("parseBoard: returns None for missing rank (only 7 ranks)"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP"
val board = FenParser.parseBoard(fen)
board shouldBe empty
test("parseBoard: returns None for invalid piece character"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNX"
val board = FenParser.parseBoard(fen)
board shouldBe empty
test("parseBoard: partial position with two kings placed correctly"):
val fen = "8/8/4k3/8/4K3/8/8/8"
val board = FenParser.parseBoard(fen)
board.map(_.pieceAt(Square(File.E, Rank.R6))) shouldBe Some(Some(Piece.BlackKing))
board.map(_.pieceAt(Square(File.E, Rank.R4))) shouldBe Some(Some(Piece.WhiteKing))
test("testRoundTripInitialPosition"):
val originalFen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR"
val board = FenParser.parseBoard(originalFen)
val exportedFen = board.map(FenExporter.boardToFen)
exportedFen shouldBe Some(originalFen)
test("testRoundTripEmptyBoard"):
val originalFen = "8/8/8/8/8/8/8/8"
val board = FenParser.parseBoard(originalFen)
val exportedFen = board.map(FenExporter.boardToFen)
exportedFen shouldBe Some(originalFen)
test("testRoundTripPartialPosition"):
val originalFen = "8/8/4k3/8/4K3/8/8/8"
val board = FenParser.parseBoard(originalFen)
val exportedFen = board.map(FenExporter.boardToFen)
exportedFen shouldBe Some(originalFen)
test("parse full FEN - initial position"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"
val gameState = FenParser.parseFen(fen)
gameState.isDefined shouldBe true
gameState.get.activeColor shouldBe Color.White
gameState.get.castlingWhite.kingSide shouldBe true
gameState.get.castlingWhite.queenSide shouldBe true
gameState.get.castlingBlack.kingSide shouldBe true
gameState.get.castlingBlack.queenSide shouldBe true
gameState.get.enPassantTarget shouldBe None
gameState.get.halfMoveClock shouldBe 0
gameState.get.fullMoveNumber shouldBe 1
test("parse full FEN - after e4"):
val fen = "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1"
val gameState = FenParser.parseFen(fen)
gameState.get.activeColor shouldBe Color.Black
gameState.get.enPassantTarget shouldBe Some(Square(File.E, Rank.R3))
test("parse full FEN - invalid parts count"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq"
val gameState = FenParser.parseFen(fen)
gameState.isDefined shouldBe false
test("parse full FEN - invalid color"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR x KQkq - 0 1"
val gameState = FenParser.parseFen(fen)
gameState.isDefined shouldBe false
test("parse full FEN - invalid castling"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w XYZ - 0 1"
val gameState = FenParser.parseFen(fen)
gameState.isDefined shouldBe false
test("parseFen: castling '-' produces CastlingRights.None for both sides"):
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w - - 0 1"
val gameState = FenParser.parseFen(fen)
gameState.isDefined shouldBe true
gameState.get.castlingWhite.kingSide shouldBe false
gameState.get.castlingWhite.queenSide shouldBe false
gameState.get.castlingBlack.kingSide shouldBe false
gameState.get.castlingBlack.queenSide shouldBe false
test("parseBoard: returns None when a rank has too many files (overflow beyond 8)"):
// "9" alone would advance fileIdx to 9, exceeding 8 → None
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBN9"
val board = FenParser.parseBoard(fen)
board shouldBe empty
test("parseBoard: returns None when a rank fails to parse (invalid middle rank)"):
// Invalid character 'X' in rank 4 should cause failure
val fen = "rnbqkbnr/pppppppp/8/8/XXXXXXXX/8/PPPPPPPP/RNBQKBNR"
val board = FenParser.parseBoard(fen)
board shouldBe empty
test("parseBoard: returns None when a rank has 9 piece characters (fileIdx > 7)"):
// 9 pawns in one rank triggers fileIdx > 7 guard (line 78)
val fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/PPPPPPPPP"
val board = FenParser.parseBoard(fen)
board shouldBe empty
@@ -1,114 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.{PieceType, *}
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{GameHistory, HistoryMove, CastleSide}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class PgnExporterTest extends AnyFunSuite with Matchers:
test("export empty game") {
val headers = Map("Event" -> "Test", "White" -> "A", "Black" -> "B")
val history = GameHistory.empty
val pgn = PgnExporter.exportGame(headers, history)
pgn.contains("[Event \"Test\"]") shouldBe true
pgn.contains("[White \"A\"]") shouldBe true
pgn.contains("[Black \"B\"]") shouldBe true
}
test("export single move") {
val headers = Map("Event" -> "Test", "White" -> "A", "Black" -> "B")
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4), None))
val pgn = PgnExporter.exportGame(headers, history)
pgn.contains("1. e4") shouldBe true
}
test("export castling") {
val headers = Map("Event" -> "Test")
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R1), Square(File.G, Rank.R1), Some(CastleSide.Kingside)))
val pgn = PgnExporter.exportGame(headers, history)
pgn.contains("O-O") shouldBe true
}
test("export game sequence") {
val headers = Map("Event" -> "Test", "White" -> "A", "Black" -> "B", "Result" -> "1-0")
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4), None))
.addMove(HistoryMove(Square(File.C, Rank.R7), Square(File.C, Rank.R5), None))
.addMove(HistoryMove(Square(File.G, Rank.R1), Square(File.F, Rank.R3), None, pieceType = PieceType.Knight))
val pgn = PgnExporter.exportGame(headers, history)
pgn.contains("1. e4 c5") shouldBe true
pgn.contains("2. Nf3") shouldBe true
}
test("export game with no headers returns only move text") {
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4), None))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn shouldBe "1. e4 *"
}
test("export queenside castling") {
val headers = Map("Event" -> "Test")
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R1), Square(File.C, Rank.R1), Some(CastleSide.Queenside)))
val pgn = PgnExporter.exportGame(headers, history)
pgn.contains("O-O-O") shouldBe true
}
test("exportGame encodes promotion to Queen as =Q suffix") {
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R7), Square(File.E, Rank.R8), None, Some(PromotionPiece.Queen)))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn should include ("e8=Q")
}
test("exportGame encodes promotion to Rook as =R suffix") {
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R7), Square(File.E, Rank.R8), None, Some(PromotionPiece.Rook)))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn should include ("e8=R")
}
test("exportGame encodes promotion to Bishop as =B suffix") {
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R7), Square(File.E, Rank.R8), None, Some(PromotionPiece.Bishop)))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn should include ("e8=B")
}
test("exportGame encodes promotion to Knight as =N suffix") {
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R7), Square(File.E, Rank.R8), None, Some(PromotionPiece.Knight)))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn should include ("e8=N")
}
test("exportGame does not add suffix for normal moves") {
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4), None, None))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn should include ("e4")
pgn should not include ("=")
}
test("exportGame uses Result header as termination marker"):
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4), None))
val pgn = PgnExporter.exportGame(Map("Result" -> "1/2-1/2"), history)
pgn should endWith("1/2-1/2")
test("exportGame with no Result header still uses * as default"):
val history = GameHistory()
.addMove(HistoryMove(Square(File.E, Rank.R2), Square(File.E, Rank.R4), None))
val pgn = PgnExporter.exportGame(Map.empty, history)
pgn shouldBe "1. e4 *"
@@ -1,451 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{GameHistory, HistoryMove, CastleSide}
import de.nowchess.chess.notation.FenParser
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class PgnParserTest extends AnyFunSuite with Matchers:
test("parse PGN headers only") {
val pgn = """[Event "Test Game"]
[Site "Earth"]
[Date "2026.03.28"]
[White "Alice"]
[Black "Bob"]
[Result "1-0"]"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
game.get.headers("Event") shouldBe "Test Game"
game.get.headers("White") shouldBe "Alice"
game.get.headers("Result") shouldBe "1-0"
game.get.moves shouldBe List()
}
test("parse PGN simple game") {
val pgn = """[Event "Test"]
[Site "?"]
[Date "2026.03.28"]
[White "A"]
[Black "B"]
[Result "*"]
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
game.get.moves.length shouldBe 6
// e4: e2-e4
game.get.moves(0).from shouldBe Square(File.E, Rank.R2)
game.get.moves(0).to shouldBe Square(File.E, Rank.R4)
}
test("parse PGN move with capture") {
val pgn = """[Event "Test"]
[White "A"]
[Black "B"]
1. e4 e5 2. Nxe5
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
game.get.moves.length shouldBe 3
// Nxe5: knight captures on e5
game.get.moves(2).to shouldBe Square(File.E, Rank.R5)
}
test("parse PGN castling") {
val pgn = """[Event "Test"]
[White "A"]
[Black "B"]
1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. O-O
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
// O-O is kingside castling: king e1-g1
val lastMove = game.get.moves.last
lastMove.from shouldBe Square(File.E, Rank.R1)
lastMove.to shouldBe Square(File.G, Rank.R1)
lastMove.castleSide.isDefined shouldBe true
}
test("parse PGN empty moves") {
val pgn = """[Event "Test"]
[White "A"]
[Black "B"]
[Result "1-0"]
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
game.get.moves.length shouldBe 0
}
test("parse PGN black kingside castling O-O") {
// After e4 e5 Nf3 Nc6 Bc4 Bc5, black can castle kingside
val pgn = """[Event "Test"]
1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. O-O O-O
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
val blackCastle = game.get.moves.last
blackCastle.castleSide shouldBe Some(CastleSide.Kingside)
blackCastle.from shouldBe Square(File.E, Rank.R8)
blackCastle.to shouldBe Square(File.G, Rank.R8)
}
test("parse PGN result tokens are skipped") {
// Result tokens like 1-0, 0-1, 1/2-1/2, * should be silently skipped
val pgn = """[Event "Test"]
1. e4 e5 1-0
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
game.get.moves.length shouldBe 2
}
test("parseAlgebraicMove: unrecognised token returns None and is skipped") {
val board = Board.initial
val history = GameHistory.empty
// "zzz" is not valid algebraic notation
val result = PgnParser.parseAlgebraicMove("zzz", board, history, Color.White)
result shouldBe None
}
test("parseAlgebraicMove: piece moves use charToPieceType for N B R Q K") {
// Test that piece type characters are recognised
val board = Board.initial
val history = GameHistory.empty
// Nf3 - knight move
val nMove = PgnParser.parseAlgebraicMove("Nf3", board, history, Color.White)
nMove.isDefined shouldBe true
nMove.get.to shouldBe Square(File.F, Rank.R3)
}
test("parseAlgebraicMove: single char that is too short returns None") {
val board = Board.initial
val history = GameHistory.empty
// Single char that is not castling and cleaned length < 2
val result = PgnParser.parseAlgebraicMove("e", board, history, Color.White)
result shouldBe None
}
test("parse PGN with file disambiguation hint") {
// Use a position where two rooks can reach the same square to test file hint
// Rooks on a1 and h1, destination d1 - "Rad1" uses file 'a' to disambiguate
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val pieces: Map[Square, Piece] = Map(
Square(File.A, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.H, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val board = Board(pieces)
val history = GameHistory.empty
val result = PgnParser.parseAlgebraicMove("Rad1", board, history, Color.White)
result.isDefined shouldBe true
result.get.from shouldBe Square(File.A, Rank.R1)
result.get.to shouldBe Square(File.D, Rank.R1)
}
test("parse PGN with rank disambiguation hint") {
// Two rooks on a1 and a4 can reach a3 - "R1a3" uses rank '1' to disambiguate
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val pieces: Map[Square, Piece] = Map(
Square(File.A, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.A, Rank.R4) -> Piece(Color.White, PieceType.Rook),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val board = Board(pieces)
val history = GameHistory.empty
val result = PgnParser.parseAlgebraicMove("R1a3", board, history, Color.White)
result.isDefined shouldBe true
result.get.from shouldBe Square(File.A, Rank.R1)
result.get.to shouldBe Square(File.A, Rank.R3)
}
test("parseAlgebraicMove: charToPieceType covers all piece letters including B R Q K") {
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
// Bishop move
val piecesForBishop: Map[Square, Piece] = Map(
Square(File.C, Rank.R1) -> Piece(Color.White, PieceType.Bishop),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val boardBishop = Board(piecesForBishop)
val bResult = PgnParser.parseAlgebraicMove("Bd2", boardBishop, GameHistory.empty, Color.White)
bResult.isDefined shouldBe true
// Rook move
val piecesForRook: Map[Square, Piece] = Map(
Square(File.A, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val boardRook = Board(piecesForRook)
val rResult = PgnParser.parseAlgebraicMove("Ra4", boardRook, GameHistory.empty, Color.White)
rResult.isDefined shouldBe true
// Queen move
val piecesForQueen: Map[Square, Piece] = Map(
Square(File.D, Rank.R1) -> Piece(Color.White, PieceType.Queen),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val boardQueen = Board(piecesForQueen)
val qResult = PgnParser.parseAlgebraicMove("Qd4", boardQueen, GameHistory.empty, Color.White)
qResult.isDefined shouldBe true
// King move
val piecesForKing: Map[Square, Piece] = Map(
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val boardKing = Board(piecesForKing)
val kResult = PgnParser.parseAlgebraicMove("Ke2", boardKing, GameHistory.empty, Color.White)
kResult.isDefined shouldBe true
}
test("parse PGN queenside castling O-O-O") {
val pgn = """[Event "Test"]
1. d4 d5 2. Nc3 Nc6 3. Bf4 Bf5 4. Qd2 Qd7 5. O-O-O
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
val lastMove = game.get.moves.last
lastMove.castleSide shouldBe Some(CastleSide.Queenside)
lastMove.from shouldBe Square(File.E, Rank.R1)
lastMove.to shouldBe Square(File.C, Rank.R1)
}
test("parse PGN black queenside castling O-O-O") {
// After sufficient moves, black castles queenside
val pgn = """[Event "Test"]
1. d4 d5 2. Nc3 Nc6 3. Bf4 Bf5 4. Qd2 Qd7 5. O-O-O O-O-O
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
val lastMove = game.get.moves.last
lastMove.castleSide shouldBe Some(CastleSide.Queenside)
lastMove.from shouldBe Square(File.E, Rank.R8)
lastMove.to shouldBe Square(File.C, Rank.R8)
}
test("parse PGN with unrecognised token in move text is silently skipped") {
// "INVALID" is not valid PGN; it should be skipped and remaining moves parsed
val pgn = """[Event "Test"]
1. e4 INVALID e5
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
// e4 parsed, INVALID skipped, e5 parsed
game.get.moves.length shouldBe 2
}
test("parseAlgebraicMove: file+rank disambiguation with piece letter") {
// "Rae1" notation: piece R, disambig "a" -> hint is "a", piece letter is uppercase first char of disambig
// But since disambig="a" which is not uppercase, the piece letter comes from clean.head
// Test "Rae1" style: R is clean.head uppercase, disambig "a" is the hint
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val pieces: Map[Square, Piece] = Map(
Square(File.A, Rank.R4) -> Piece(Color.White, PieceType.Rook),
Square(File.H, Rank.R4) -> Piece(Color.White, PieceType.Rook),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val board = Board(pieces)
val history = GameHistory.empty
// "Rae4" - Rook from a-file to e4; disambig = "a", clean.head = 'R' uppercase
val result = PgnParser.parseAlgebraicMove("Rae4", board, history, Color.White)
result.isDefined shouldBe true
result.get.from shouldBe Square(File.A, Rank.R4)
result.get.to shouldBe Square(File.E, Rank.R4)
}
test("parseAlgebraicMove: charToPieceType returns None for unknown character") {
// 'Z' is not a valid piece letter - the regex clean should return None
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val board = Board.initial
val history = GameHistory.empty
// "Ze4" - Z is not a valid piece, charToPieceType('Z') returns None
// The result will be None because requiredPieceType is None and filtering by None.forall = true
// so it finds any piece that can reach e4, but since clean="Ze4" -> destStr="e4", disambig="Z"
// disambig.head.isUpper so charToPieceType('Z') is called
val result = PgnParser.parseAlgebraicMove("Ze4", board, history, Color.White)
// With None piece type, forall(pt => ...) is vacuously true so any piece reaching e4 is candidate
// But there's no piece named Z so requiredPieceType=None, meaning any piece can match
// This tests that charToPieceType('Z') returns None without crashing
result shouldBe defined // will find a pawn or whatever reaches e4
}
test("parseAlgebraicMove: uppercase dest-only notation hits clean.head.isUpper and charToPieceType unknown char") {
// "E4" - clean = "E4", disambig = "", clean.head = 'E' is upper, charToPieceType('E') returns None
// This exercises line 97 (else if clean.head.isUpper) and line 152 (case _ => None)
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val board = Board.initial
val history = GameHistory.empty
// 'E' is not a valid piece type but we still get a result since requiredPieceType is None
val result = PgnParser.parseAlgebraicMove("E4", board, history, Color.White)
// Result may be defined (pawn that can reach e4) or None; main goal is no crash and line coverage
result should not be null // just verifies code path executes without exception
}
test("parseAlgebraicMove: rank disambiguation with digit outside 1-8 hits matchesHint else-true branch") {
// Build a board with a Rook that can be targeted with a disambiguation hint containing '9'
// hint = "9" → c = '9', not in a-h, not in 1-8, triggers else true
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val pieces: Map[Square, Piece] = Map(
Square(File.A, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.H, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
val board = Board(pieces)
val history = GameHistory.empty
// "R9d1" - clean = "R9d1", destStr = "d1", disambig = "R9"
// disambig.head = 'R' is upper -> charToPieceType('R') = Rook, hint = "9"
// matchesHint called with hint "9" -> '9' not in a-h, not in 1-8 -> else true
val result = PgnParser.parseAlgebraicMove("R9d1", board, history, Color.White)
// Should find a rook (hint "9" matches everything)
result.isDefined shouldBe true
result.get.to shouldBe Square(File.D, Rank.R1)
}
test("parseAlgebraicMove preserves promotion to Queen in HistoryMove") {
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = PgnParser.parseAlgebraicMove("e7e8=Q", board, GameHistory.empty, Color.White)
result.isDefined should be (true)
result.get.promotionPiece should be (Some(PromotionPiece.Queen))
result.get.to should be (Square(File.E, Rank.R8))
}
test("parseAlgebraicMove preserves promotion to Rook") {
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = PgnParser.parseAlgebraicMove("e7e8=R", board, GameHistory.empty, Color.White)
result.get.promotionPiece should be (Some(PromotionPiece.Rook))
}
test("parseAlgebraicMove preserves promotion to Bishop") {
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = PgnParser.parseAlgebraicMove("e7e8=B", board, GameHistory.empty, Color.White)
result.get.promotionPiece should be (Some(PromotionPiece.Bishop))
}
test("parseAlgebraicMove preserves promotion to Knight") {
val board = FenParser.parseBoard("8/4P3/4k3/8/8/8/8/8").get
val result = PgnParser.parseAlgebraicMove("e7e8=N", board, GameHistory.empty, Color.White)
result.get.promotionPiece should be (Some(PromotionPiece.Knight))
}
test("parsePgn applies promoted piece to board for subsequent moves") {
// Build a board with a white pawn on e7 plus the two kings
import de.nowchess.api.board.{Board, Square, File, Rank, Piece, Color, PieceType}
val pieces: Map[Square, Piece] = Map(
Square(File.E, Rank.R7) -> Piece(Color.White, PieceType.Pawn),
Square(File.E, Rank.R1) -> Piece(Color.White, PieceType.King),
Square(File.H, Rank.R1) -> Piece(Color.Black, PieceType.King)
)
val board = Board(pieces)
val move = PgnParser.parseAlgebraicMove("e7e8=Q", board, GameHistory.empty, Color.White)
move.isDefined should be (true)
move.get.promotionPiece should be (Some(PromotionPiece.Queen))
// After applying the promotion the square e8 should hold a White Queen
val (boardAfterPawnMove, _) = board.withMove(move.get.from, move.get.to)
val promotedBoard = boardAfterPawnMove.updated(move.get.to, Piece(Color.White, PieceType.Queen))
promotedBoard.pieceAt(Square(File.E, Rank.R8)) should be (Some(Piece(Color.White, PieceType.Queen)))
}
test("parsePgn with all four promotion piece types (Queen, Rook, Bishop, Knight) in sequence") {
// This test exercises lines 53-58 in PgnParser.parseMovesText which contain
// the pattern match over PromotionPiece for Queen, Rook, Bishop, Knight
val pgn = """[Event "Promotion Test"]
[White "A"]
[Black "B"]
1. a2a3 h7h5 2. a3a4 h5h4 3. a4a5 h4h3 4. a5a6 h3h2 5. a6a7 h2h1=Q 6. a7a8=R 1-0
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
// Move 10 is h2h1=Q (black pawn promotes to queen)
val blackPromotionToQ = game.get.moves(9) // 0-indexed
blackPromotionToQ.promotionPiece shouldBe Some(PromotionPiece.Queen)
// Move 11 is a7a8=R (white pawn promotes to rook)
val whitePromotionToR = game.get.moves(10)
whitePromotionToR.promotionPiece shouldBe Some(PromotionPiece.Rook)
}
test("parseAlgebraicMove promotion with Rook through full PGN parse") {
val pgn = """[Event "Test"]
[White "A"]
[Black "B"]
1. a2a3 h7h6 2. a3a4 h6h5 3. a4a5 h5h4 4. a5a6 h4h3 5. a6a7 h3h2 6. a7a8=R
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
val lastMove = game.get.moves.last
lastMove.promotionPiece shouldBe Some(PromotionPiece.Rook)
}
test("parseAlgebraicMove promotion with Bishop through full PGN parse") {
val pgn = """[Event "Test"]
[White "A"]
[Black "B"]
1. b2b3 h7h6 2. b3b4 h6h5 3. b4b5 h5h4 4. b5b6 h4h3 5. b6b7 h3h2 6. b7b8=B
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
val lastMove = game.get.moves.last
lastMove.promotionPiece shouldBe Some(PromotionPiece.Bishop)
}
test("parseAlgebraicMove promotion with Knight through full PGN parse") {
val pgn = """[Event "Test"]
[White "A"]
[Black "B"]
1. c2c3 h7h6 2. c3c4 h6h5 3. c4c5 h5h4 4. c5c6 h4h3 5. c6c7 h3h2 6. c7c8=N
"""
val game = PgnParser.parsePgn(pgn)
game.isDefined shouldBe true
val lastMove = game.get.moves.last
lastMove.promotionPiece shouldBe Some(PromotionPiece.Knight)
}
test("extractPromotion returns None for invalid promotion letter") {
// Regex =([A-Z]) now captures any uppercase letter, so =X is matched but case _ => None fires
val result = PgnParser.extractPromotion("e7e8=X")
result shouldBe None
}
test("extractPromotion returns None when no promotion in notation") {
val result = PgnParser.extractPromotion("e7e8")
result shouldBe None
}
@@ -1,119 +0,0 @@
package de.nowchess.chess.notation
import de.nowchess.api.board.*
import de.nowchess.api.move.PromotionPiece
import de.nowchess.chess.logic.{GameHistory, HistoryMove, CastleSide}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class PgnValidatorTest extends AnyFunSuite with Matchers:
test("validatePgn: valid simple game returns Right with correct moves"):
val pgn =
"""[Event "Test"]
[White "A"]
[Black "B"]
1. e4 e5 2. Nf3 Nc6
"""
PgnParser.validatePgn(pgn) match
case Right(game) =>
game.moves.length shouldBe 4
game.headers("Event") shouldBe "Test"
game.moves(0).from shouldBe Square(File.E, Rank.R2)
game.moves(0).to shouldBe Square(File.E, Rank.R4)
case Left(err) => fail(s"Expected Right but got Left($err)")
test("validatePgn: empty move text returns Right with no moves"):
val pgn = "[Event \"Test\"]\n[White \"A\"]\n[Black \"B\"]\n"
PgnParser.validatePgn(pgn) match
case Right(game) => game.moves shouldBe empty
case Left(err) => fail(s"Expected Right but got Left($err)")
test("validatePgn: impossible position returns Left"):
// "Nf6" without any preceding moves — there is no knight that can reach f6 from f3 yet
// but e4 e5 Nf3 is OK; then Nd4 — knight on f3 can go to d4
// Let's use a clearly impossible move: "Qd4" from the initial position (queen can't move)
val pgn =
"""[Event "Test"]
1. Qd4
"""
PgnParser.validatePgn(pgn) match
case Left(_) => succeed
case Right(g) => fail(s"Expected Left but got Right with ${g.moves.length} moves")
test("validatePgn: unrecognised token returns Left"):
val pgn =
"""[Event "Test"]
1. e4 GARBAGE e5
"""
PgnParser.validatePgn(pgn) match
case Left(_) => succeed
case Right(g) => fail(s"Expected Left but got Right with ${g.moves.length} moves")
test("validatePgn: result tokens are skipped (not treated as errors)"):
val pgn =
"""[Event "Test"]
1. e4 e5 1-0
"""
PgnParser.validatePgn(pgn) match
case Right(game) => game.moves.length shouldBe 2
case Left(err) => fail(s"Expected Right but got Left($err)")
test("validatePgn: valid kingside castling is accepted"):
val pgn =
"""[Event "Test"]
1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. O-O
"""
PgnParser.validatePgn(pgn) match
case Right(game) =>
game.moves.last.castleSide shouldBe Some(CastleSide.Kingside)
case Left(err) => fail(s"Expected Right but got Left($err)")
test("validatePgn: castling when not legal returns Left"):
// Try to castle on move 1 — impossible from initial position (pieces in the way)
val pgn =
"""[Event "Test"]
1. O-O
"""
PgnParser.validatePgn(pgn) match
case Left(_) => succeed
case Right(g) => fail(s"Expected Left but got Right with ${g.moves.length} moves")
test("validatePgn: valid queenside castling is accepted"):
val pgn =
"""[Event "Test"]
1. d4 d5 2. Nc3 Nc6 3. Bf4 Bf5 4. Qd2 Qd7 5. O-O-O
"""
PgnParser.validatePgn(pgn) match
case Right(game) =>
game.moves.last.castleSide shouldBe Some(CastleSide.Queenside)
case Left(err) => fail(s"Expected Right but got Left($err)")
test("validatePgn: disambiguation with two rooks is accepted"):
val pieces: Map[Square, Piece] = Map(
Square(File.A, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.H, Rank.R1) -> Piece(Color.White, PieceType.Rook),
Square(File.E, Rank.R4) -> Piece(Color.White, PieceType.King),
Square(File.E, Rank.R8) -> Piece(Color.Black, PieceType.King)
)
// Build PGN from this custom board is hard, so test strictParseAlgebraicMove directly
val board = Board(pieces)
// Both rooks can reach d1 — "Rad1" should pick the a-file rook
val result = PgnParser.validatePgn("[Event \"T\"]\n\n1. e4")
// This tests the main flow; below we test disambiguation in isolation
result.isRight shouldBe true
test("validatePgn: ambiguous move without disambiguation returns Left"):
// Set up a position where two identical pieces can reach the same square
// We can test this via the strict path: two rooks, target square, no disambiguation hint
// Build it through a sequence that leads to two rooks on same file targeting same square
// This is hard to construct via PGN alone; verify via a known impossible disambiguation
val pgn = "[Event \"T\"]\n\n1. e4"
PgnParser.validatePgn(pgn).isRight shouldBe true
@@ -1,168 +0,0 @@
package de.nowchess.chess.observer
import de.nowchess.api.board.{Board, Color}
import de.nowchess.chess.logic.GameHistory
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
import scala.collection.mutable
class ObservableThreadSafetyTest extends AnyFunSuite with Matchers:
private class TestObservable extends Observable:
def testNotifyObservers(event: GameEvent): Unit =
notifyObservers(event)
private class CountingObserver extends Observer:
@volatile private var eventCount = 0
@volatile private var lastEvent: Option[GameEvent] = None
def onGameEvent(event: GameEvent): Unit =
eventCount += 1
lastEvent = Some(event)
private def createTestEvent(): GameEvent =
BoardResetEvent(
board = Board.initial,
history = GameHistory.empty,
turn = Color.White
)
test("Observable is thread-safe for concurrent subscribe and notify"):
val observable = new TestObservable()
val testEvent = createTestEvent()
@volatile var raceConditionCaught = false
// Thread 1: repeatedly notifies observers with long iteration
val notifierThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500000 do
observable.testNotifyObservers(testEvent)
} catch {
case _: java.util.ConcurrentModificationException =>
raceConditionCaught = true
}
}
})
// Thread 2: rapidly subscribes/unsubscribes observers during notify
val subscriberThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500000 do
val obs = new CountingObserver()
observable.subscribe(obs)
observable.unsubscribe(obs)
} catch {
case _: java.util.ConcurrentModificationException =>
raceConditionCaught = true
}
}
})
notifierThread.start()
subscriberThread.start()
notifierThread.join()
subscriberThread.join()
raceConditionCaught shouldBe false
test("Observable is thread-safe for concurrent subscribe, unsubscribe, and notify"):
val observable = new TestObservable()
val testEvent = createTestEvent()
val exceptions = mutable.ListBuffer[Exception]()
val observers = mutable.ListBuffer[CountingObserver]()
// Pre-subscribe some observers
for _ <- 1 to 10 do
val obs = new CountingObserver()
observers += obs
observable.subscribe(obs)
// Thread 1: notifies observers
val notifierThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 5000 do
observable.testNotifyObservers(testEvent)
} catch {
case e: Exception => exceptions += e
}
}
})
// Thread 2: subscribes new observers
val subscriberThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 5000 do
val obs = new CountingObserver()
observable.subscribe(obs)
} catch {
case e: Exception => exceptions += e
}
}
})
// Thread 3: unsubscribes observers
val unsubscriberThread = new Thread(new Runnable {
def run(): Unit = {
try {
for i <- 1 to 5000 do
if observers.nonEmpty then
val obs = observers(i % observers.size)
observable.unsubscribe(obs)
} catch {
case e: Exception => exceptions += e
}
}
})
notifierThread.start()
subscriberThread.start()
unsubscriberThread.start()
notifierThread.join()
subscriberThread.join()
unsubscriberThread.join()
exceptions.isEmpty shouldBe true
test("Observable.observerCount is thread-safe during concurrent modifications"):
val observable = new TestObservable()
val exceptions = mutable.ListBuffer[Exception]()
val countResults = mutable.ListBuffer[Int]()
// Thread 1: subscribes observers
val subscriberThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500 do
observable.subscribe(new CountingObserver())
} catch {
case e: Exception => exceptions += e
}
}
})
// Thread 2: reads observer count
val readerThread = new Thread(new Runnable {
def run(): Unit = {
try {
for _ <- 1 to 500 do
val count = observable.observerCount
countResults += count
} catch {
case e: Exception => exceptions += e
}
}
})
subscriberThread.start()
readerThread.start()
subscriberThread.join()
readerThread.join()
exceptions.isEmpty shouldBe true
// Count should never go backwards
for i <- 1 until countResults.size do
countResults(i) >= countResults(i - 1) shouldBe true
@@ -1,43 +0,0 @@
package de.nowchess.chess.view
import de.nowchess.api.board.Piece
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class PieceUnicodeTest extends AnyFunSuite with Matchers:
test("White King maps to "):
Piece.WhiteKing.unicode shouldBe "\u2654"
test("White Queen maps to ♕"):
Piece.WhiteQueen.unicode shouldBe "\u2655"
test("White Rook maps to "):
Piece.WhiteRook.unicode shouldBe "\u2656"
test("White Bishop maps to ♗"):
Piece.WhiteBishop.unicode shouldBe "\u2657"
test("White Knight maps to "):
Piece.WhiteKnight.unicode shouldBe "\u2658"
test("White Pawn maps to ♙"):
Piece.WhitePawn.unicode shouldBe "\u2659"
test("Black King maps to "):
Piece.BlackKing.unicode shouldBe "\u265A"
test("Black Queen maps to ♛"):
Piece.BlackQueen.unicode shouldBe "\u265B"
test("Black Rook maps to "):
Piece.BlackRook.unicode shouldBe "\u265C"
test("Black Bishop maps to ♝"):
Piece.BlackBishop.unicode shouldBe "\u265D"
test("Black Knight maps to "):
Piece.BlackKnight.unicode shouldBe "\u265E"
test("Black Pawn maps to ♟"):
Piece.BlackPawn.unicode shouldBe "\u265F"
@@ -1,41 +0,0 @@
package de.nowchess.chess.view
import de.nowchess.api.board.{Board, File, Piece, Rank, Square}
import org.scalatest.funsuite.AnyFunSuite
import org.scalatest.matchers.should.Matchers
class RendererTest extends AnyFunSuite with Matchers:
test("render contains column header with all file labels"):
Renderer.render(Board.initial) should include("a b c d e f g h")
test("render output begins with the column header"):
Renderer.render(Board.initial) should startWith(" a b c d e f g h")
test("render contains rank labels 1 through 8"):
val output = Renderer.render(Board.initial)
for rank <- 1 to 8 do output should include(s"$rank ")
test("render shows white king unicode symbol for initial board"):
Renderer.render(Board.initial) should include("\u2654")
test("render shows black king unicode symbol for initial board"):
Renderer.render(Board.initial) should include("\u265A")
test("render contains ANSI light-square background code"):
Renderer.render(Board.initial) should include("\u001b[48;5;223m")
test("render contains ANSI dark-square background code"):
Renderer.render(Board.initial) should include("\u001b[48;5;130m")
test("render uses white-piece foreground color for white pieces"):
Renderer.render(Board.initial) should include("\u001b[97m")
test("render uses black-piece foreground color for black pieces"):
Renderer.render(Board.initial) should include("\u001b[30m")
test("render of empty board contains no piece unicode"):
val output = Renderer.render(Board(Map.empty))
output should include("a b c d e f g h")
output should not include "\u2654"
output should not include "\u265A"