src/Tests/Unit/GeometryTest.py

   1 import unittest
   2
   3 import Tests.Fixtures
   4 from Geometry import *
   5
   6
   7 class TwoVectorTest(unittest.TestCase):
   8
   9     def testAdd(self):
  10         """
  11         Add a couple of test vectors and check that they sum
  12         correctly.
  13         """
  14         v1 = TwoVector(0,0)
  15         v2 = TwoVector(100, -19)
  16         self.assertTrue(v2 == (v1+v2))
  17
  18         v1 = TwoVector(23, -10)
  19         v2 = TwoVector(-23, 10)
  20         zero = TwoVector(0, 0)
  21         self.assertTrue((v1+v2) == zero)
  22
  23
  24     def testDotProduct(self):
  25         """
  26         The dot product of a vector v with a vector to which it's
  27         perpendicular, v_perp, should always be zero.
  28
  29         The dot product of any vector with the zero vector should be
  30         zero.
  31         """
  32         v1 = TwoVector(235, -2352)
  33         v2 = TwoVector(9382335.024, -235235.1242)
  34         self.assertEqual(0, v1.dot_product(v1.perpendicular()))
  35         self.assertEqual(0, v2.dot_product(v2.perpendicular()))
  36
  37         zero = TwoVector(0, 0)
  38         self.assertEqual(0, v1.dot_product(zero))
  39
  40
  41
  42 class PolygonTest(unittest.TestCase):
  43
  44     def testEquals(self):
  45         """
  46         We defined our own __eq__ method; make sure it works.
  47         """
  48         unit_square1 = Polygon([ (0,0), (1,0), (1,1), (0,1) ])
  49         unit_square2 = Polygon([ (0,0), (1,0), (1,1), (0,1) ])
  50         self.assertTrue(unit_square1 == unit_square2)
  51
  52         hexagon = Polygon([ (1,0),
  53                             (0.5, sqrt(3)/2.0),
  54                             (-0.5, sqrt(3)/2.0),
  55                             (-1, 0),
  56                             (-0.5, -sqrt(3)/2.0),
  57                             (0.5, -sqrt(3)/2.0) ])
  58
  59         self.assertFalse(unit_square1 == hexagon)
  60
  61
  62     def testDrag(self):
  63         """
  64         Drag the unit square 5 units to the right.
  65         """
  66         unit_square = Polygon([ (0,0), (1,0), (1,1), (0,1) ])
  67         v = TwoVector(5,0)
  68         result = unit_square.drag(v)
  69         expected_result = Polygon([ (0,0), (6,0), (6,1), (0,1) ])
  70         self.assertTrue(result == expected_result)
  71
  72
  73
  74     def testDragVertices(self):
  75         """
  76         A diamond shape has nice drag vertices which we can calculate
  77         by hand.
  78         """
  79         diamond = Polygon([ (0,1), (-1,0), (0,-1), (1,0) ])
  80
  81         # First, we drag it to the right along the x-axis.
  82         drag_vector = TwoVector(5,0)
  83         dvs = set(diamond.drag_vertices(drag_vector))
  84         expected_dvs = set([(0,1), (0,-1)])
  85         self.assertTrue(dvs == expected_dvs)
  86
  87         # Now, drag it up.
  88         drag_vector = TwoVector(0,5)
  89         dvs = set(diamond.drag_vertices(drag_vector))
  90         expected_dvs = set([(1,0), (-1,0)])
  91         self.assertTrue(dvs == expected_dvs)
  92
  93
  94 def suite():
  95     suite = unittest.TestSuite()
  96     suite.addTest(unittest.makeSuite(TwoVectorTest))
  97     suite.addTest(unittest.makeSuite(PolygonTest))
  98     return suite