Add RulesetError test case.

Remove old comments.

ruleset.go

@@ -1,10 +1,36 @@
 package rules
 
+type RulesetError string
+
+func (err RulesetError) Error() string { return string(err) }
+
 const (
 	MoveUp    = "up"
 	MoveDown  = "down"
 	MoveRight = "right"
 	MoveLeft  = "left"
+
+	BoardSizeSmall  = 7
+	BoardSizeMedium = 11
+	BoardSizeLarge  = 19
+
+	SnakeMaxHealth = 100
+	SnakeStartSize = 3
+
+	// bvanvugt - TODO: Just return formatted strings instead of codes?
+	NotEliminated                   = ""
+	EliminatedByCollision           = "snake-collision"
+	EliminatedBySelfCollision       = "snake-self-collision"
+	EliminatedByOutOfHealth         = "out-of-health"
+	EliminatedByHeadToHeadCollision = "head-collision"
+	EliminatedByOutOfBounds         = "wall-collision"
+
+	// TODO - Error consts
+	ErrorTooManySnakes   = RulesetError("too many snakes for fixed start positions")
+	ErrorNoRoomForSnake  = RulesetError("not enough space to place snake")
+	ErrorNoRoomForFood   = RulesetError("not enough space to place food")
+	ErrorNoMoveFound     = RulesetError("move not provided for snake")
+	ErrorZeroLengthSnake = RulesetError("snake is length zero")
 )
 
 type Point struct {
@@ -37,7 +63,3 @@ type Ruleset interface {
 	CreateNextBoardState(prevState *BoardState, moves []SnakeMove) (*BoardState, error)
 	IsGameOver(state *BoardState) (bool, error)
 }
-
-type RulesetError string
-
-func (err RulesetError) Error() string { return string(err) }

ruleset_test.go

@@ -0,0 +1,12 @@
+package rules
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestRulesetError(t *testing.T) {
+	err := (error)(RulesetError("test error string"))
+	require.Equal(t, "test error string", err.Error())
+}

standard.go

@@ -1,7 +1,6 @@
 package rules
 
 import (
-	//"errors"
 	"math/rand"
 	"sort"
 )
@@ -11,33 +10,6 @@ type StandardRuleset struct {
 	MinimumFood     int32
 }
 
-const (
-	BoardSizeSmall  = 7
-	BoardSizeMedium = 11
-	BoardSizeLarge  = 19
-
-	SnakeMaxHealth = 100
-	SnakeStartSize = 3
-
-	// bvanvugt - TODO: Just return formatted strings instead of codes?
-	NotEliminated                   = ""
-	EliminatedByCollision           = "snake-collision"
-	EliminatedBySelfCollision       = "snake-self-collision"
-	EliminatedByOutOfHealth         = "out-of-health"
-	EliminatedByHeadToHeadCollision = "head-collision"
-	EliminatedByOutOfBounds         = "wall-collision"
-
-	// TODO - Error consts
-	ErrorTooManySnakes  = RulesetError("too many snakes for fixed start positions")
-	ErrorNoRoomForSnake = RulesetError("not enough space to place snake")
-	ErrorNoRoomForFood  = RulesetError("not enough space to place food")
-	ErrorNoMoveFound    = RulesetError("move not provided for snake")
-
-	// TODO: These two error codes seem equivalent, Do we only need one ?
-	ErrorSizeZeroBody    = RulesetError("found snake with zero size body")
-	ErrorZeroLengthSnake = RulesetError("snake is length zero")
-)
-
 func (r *StandardRuleset) CreateInitialBoardState(width int32, height int32, snakeIDs []string) (*BoardState, error) {
 	initialBoardState := &BoardState{
 		Height: height,
@@ -263,7 +235,7 @@ func (r *StandardRuleset) moveSnakes(b *BoardState, moves []SnakeMove) error {
 		}
 
 		if len(snake.Body) == 0 {
-			return ErrorSizeZeroBody
+			return ErrorZeroLengthSnake
 		}
 		moveFound := false
 		for _, move := range moves {

standard_test.go

@@ -1,7 +1,6 @@
 package rules
 
 import (
-	//"errors"
 	"math"
 	"math/rand"
 	"testing"
@@ -513,7 +512,7 @@ func TestCreateNextBoardState(t *testing.T) {
 				{ID: "one", Move: MoveUp},
 				{ID: "two", Move: MoveDown},
 			},
-			ErrorSizeZeroBody,
+			ErrorZeroLengthSnake,
 			nil,
 		},
 		{
@@ -940,7 +939,7 @@ func TestMoveSnakesWrongID(t *testing.T) {
 
 	r := StandardRuleset{}
 	err := r.moveSnakes(b, moves)
-	require.Equal(t, ErrorNoMoveFound, err) // TODO: @bvanvugt is this a place where an "==" comparision should be used ?
+	require.Equal(t, ErrorNoMoveFound, err)
 }
 
 func TestMoveSnakesNotEnoughMoves(t *testing.T) {