Bowling: starts a new frame when the current frame is over

spec/BowlingSpec.js

@@ -25,5 +25,19 @@
       game.throwBall(1);
       expect(game.getCurrentFrame().getFirstScore()).toBe(1);
     });
+    it('scores a frame when two balls are thrown', function() {
+      game.newFrame();
+      game.throwBall(1);
+      game.throwBall(2);
+      expect(game.getCurrentFrame().getSecondScore()).toBe(2);
+    });
+    it('starts a new frame when the current frame is over', function() {
+      game.newFrame();
+      game.throwBall(1);
+      game.throwBall(2);
+      game.throwBall(3);
+      expect(game.getFrames().length).toBe(2);
+      expect(game.getCurrentFrame().getFirstScore()).toBe(3);
+    });
   });
 }());

spec/FrameSpec.js

@@ -14,5 +14,10 @@
       expect(frame.getFirstScore()).toBe(5);
       expect(frame.getSecondScore()).toBe(4);
     });
+    it('is over after scoring two throws', function() {
+      frame.score(5);
+      frame.score(4);
+      expect(frame.isOver()).toBe(true);
+    });
   });
 }());

src/Bowling.js

@@ -5,8 +5,15 @@ var Bowling = function() {
 };
 Bowling.prototype.pinsLeft = function() { return this._pinsLeft; };
 Bowling.prototype.throwBall = function(pinsHit) {
-  this._pinsLeft -= pinsHit;
-  this.getCurrentFrame().score(pinsHit);
+  if (this.getCurrentFrame().isOver()) {
+    this.newFrame();
+    this._currentFrame += 1;
+    this._pinsLeft -= pinsHit;
+    this.getCurrentFrame().score(pinsHit);
+  } else {
+    this._pinsLeft -= pinsHit;
+    this.getCurrentFrame().score(pinsHit);
+  }
  };
 Bowling.prototype.newFrame = function() { this._frames.push(new Frame()); };
 Bowling.prototype.getFrames = function() { return this._frames; };

src/Frame.js

@@ -4,3 +4,4 @@ var Frame = function() {
 Frame.prototype.score = function(pinsHit) { this._score.push(pinsHit); };
 Frame.prototype.getFirstScore = function() { return this._score[0]; };
 Frame.prototype.getSecondScore = function() { return this._score[1]; };
+Frame.prototype.isOver = function() { return this._score.length === 2; };