add tests for adding Vectors

src/fancymath/vector.py

@@ -30,6 +30,12 @@ class Vector(object):
         s = "Vector(x=%s, y=%s, z=%s)" % (self.x, self.y, self.z)
         return s
 
+    def __add__(self, other):
+        x = self.x + other.x
+        y = self.y + other.y
+        z = self.z + other.z
+        return self.__class__(x, y, z)
+
 
 if __name__ == "__main__":
     v1 = Vector(3, 4, 0)

test/test_vector.py

@@ -0,0 +1,12 @@
+import unittest
+
+from fancymath.vector import Vector
+
+
+class TestVector(unittest.TestCase):
+    def test_add_vector(self):
+        v1 = Vector(1, 2, 3)
+        v2 = Vector(-3, -2, -1)
+        v3 = v1 + v2
+        self.assertIsInstance(v3, Vector)
+        self.assertEqual(v3.x, v1.x + v2.x)