Ensuring the game can display itself

albeit in very simple string form.

conway/go/conway_test.go

@@ -1,6 +1,7 @@
 package conway_test
 
 import (
+	"fmt"
 	"testing"
 )
 
@@ -113,6 +114,24 @@ func TestDeadCellWithExactlyThreeLiveNeighborsBecomesAlive(t *testing.T) {
 	}
 }
 
+func TestGameOfLifeCanDisplayItself(t *testing.T) {
+	game := NewGameOfLife(16, 16)
+
+	err := game.ImportState(TEST_SIMPLE_INITIAL_STATE)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	grid := fmt.Sprintf("%s\n", game)
+
+	gridLen := len(grid)
+	if gridLen < 256 {
+		t.Errorf("%v < 256", gridLen)
+		t.Fail()
+	}
+}
+
 func TestNewGameOfLifeHasCorrectDimensions(t *testing.T) {
 	game := NewGameOfLife(16, 16)
 	if game.State.Height() != 16 || game.State.Width() != 16 {

conway/go/game_of_life.go

@@ -3,6 +3,7 @@ package conway
 import (
 	"errors"
 	"fmt"
+	"strings"
 )
 
 type GameOfLife struct {
@@ -171,6 +172,32 @@ func (game *GameOfLife) ImportState(state *GameState) error {
 	return game.State.Import(state)
 }
 
+func (game *GameOfLife) String() string {
+	var rows []string
+
+	height := game.State.Height()
+	width := game.State.Width()
+
+	for y := 0; y < height; y++ {
+		var cells []string
+		for x := 0; x < width; x++ {
+			stringVal := "X"
+
+			value, err := game.State.Get(x, y)
+			if err != nil {
+				return ""
+			}
+
+			if value == 0 {
+				stringVal = "_"
+			}
+			cells = append(cells, stringVal)
+		}
+		rows = append(rows, strings.Join(cells, ""))
+	}
+	return strings.Join(rows, "\n")
+}
+
 func NewGenerationScoreCard(height, width int) *GenerationScoreCard {
 	genScore := &GenerationScoreCard{}
 	for i := 0; i < height; i++ {