anchor.diff:      });
     });
   
  -  group("GetDirection", () {});
  +  group("GetDirection", () {
  +    DirectionSystem directionSystem;
  +    setUp(() {
  +      directionSystem = new DirectionSystem();
  +    });
  +    tearDown(() {
  +      directionSystem = null;
  +    });
  +    test("Get main directions", () {
  +      testGetDirections(directionSystem, Direction.MAIN_DIRECTIONS, [{
  +          "x": 0,
  +          "y": -1
  +        }, {
  +          "x": 0,
  +          "y": 1
  +        }, {
  +          "x": -1,
  +          "y": 0
  +        }, {
  +          "x": 1,
  +          "y": 0
  +        }]);
  +    });
  +    test("Get diagonal directions", () {
  +      testGetDirections(directionSystem, Direction.DIAGONAL_DIRECTIONS, [{
  +          "x": -expectedDiagonalValue,
  +          "y": -expectedDiagonalValue
  +        }, {
  +          "x": expectedDiagonalValue,
  +          "y": -expectedDiagonalValue
  +        }, {
  +          "x": -expectedDiagonalValue,
  +          "y": expectedDiagonalValue
  +        }, {
  +          "x": expectedDiagonalValue,
  +          "y": expectedDiagonalValue
  +        }]);
  +    });
  +  });
   
     group("NullMainDirection", () {
       DirectionSystem directionSystem;
  
positive.code:   }
  }
  
  num _makeRadians(num angles) => angles * (PI / 180);
  
negative.code:     tearDown(() {
        directionSystem = null;
      });
      test("Rotate 45 angles diagonal directions", () {
        directionSystem.rotateDirectionsAngles(45);
        testDirection(directionSystem.upLeftDirection, -1, 0);
        testDirection(directionSystem.upRightDirection, 1, 0);
        testDirection(directionSystem.downLeftDirection, 0, -1);
        testDirection(directionSystem.downRightDirection, 0, 1);
      });
      test("Rotate 90 angles main directions", () {
        directionSystem.rotateDirectionsAngles(90);
        testDirection(directionSystem.upDirection, 1, 0);
        testDirection(directionSystem.downDirection, -1, 0);
        testDirection(directionSystem.leftDirection, 0, -1);
        testDirection(directionSystem.rightDirection, 0, 1);
      });
    });
  
  