anchor.diff:          }], true);
       });
       test("Testing diagonal directions", () {
  -      testAddToMainDirections(directionSystem, Direction.DIAGONAL_DIRECTIONS, [{
  +      testAddToMainDirection(directionSystem, Direction.DIAGONAL_DIRECTIONS, [{
             "x": -expectedDiagonalValue,
             "y": -expectedDiagonalValue
           }, {
  
positive.code:   }
  }
  
  num _makeRadians(num angles) => angles * (PI / 180);
  
negative.code:       directionSystem = null;
      });
      test("Testing main directions", () {
        testAddToMainDirection(directionSystem, Direction.MAIN_DIRECTIONS, [{
            "x": 0,
            "y": -1
          }, {
  